For each of the 39 nodes in the traces, we simulated the capture at the beginning of each of these intervals.

the .rst capture is simulated at 100,000 seconds from the network deployment, and the last capture is simulated at 359,200 seconds from the network deployment (12·6 hours later).


Let p be a protocol that realizes the value Iµ := ICµ(f,.).


Also, our scheme works at the granularity of the memory object level.

the access permission level is always set for the whole memory object.


Informally,itisatechnique to lure the victim into clicking on a certain element of a page, while her intention is to interact with the content of a di.erent site.

even though the victim is under the impression of clicking on a seemingly harmless page, she is actually clicking on an element of the attacker s choice.


Though the rate of illegitimate attestations is bounded by that of human activity, smart attackers can deterministically bypass any spam .lter based on human attestation.

bots could generate sophisticated spam messages for targeted users or act like humans when they access Internet banking or E-commerce sites if they adopt existing methods as human identi.cation.


In our research, the emphasis is on activities where security is not or should not be the primary activity of using computing.

privacy and security have become issues in almost all computing applications but we have followed a general approach of how people might focus on their primary objectives and not secondary issues.


Although this can be computationally ine.cient, it assures that if she does not possess the right credentials, she learns almost nothing about the policy controlling access to the message.

she doesn t learn what credentials she would need to obtain in order to decrypt the message.


However, in order to handle negative authorizations (which is an extension of RBAC) each role has two correspoding classes, eachpermissionorprohibitiononaresourcehas corresponding classes for roles and users.

for each permission, we have a class of roles that have that permission, and thena classof userswhohave thatpermission.


More precisely, if u requires the read privilege Read, the system has to query the instances of object property Read and PRead.

both the queries look for instance  (i.e.,:Read and :PRead).


When it is composite, the polynomial ring over the message space is not a unique factorization domain, and hence they cannot e.ciently obtain the exact corresponding set from the polynomial.

the message space of Paillier encryption is ZN for a hard-to-factor integer N. In this case, .nding roots of the polynomial in ZN is equivalent to factoring N [44].


We develop three types of one-gate HT benchmarks based on switching power, leakage power, and delay measurements that are commonly used in HT detection.

we employ an iterative searching algorithm to .nd rarely switching locations, an aging-based approach to create ultralow power HT, and a backtracking-based reconvergence identi.cation method to determine the non-observable delay paths.


Speci.cally, the group manager picks one from every d consecutive sessions in a particular window of sessions and includes key shares for those selected sessions in the key distribution message.

the recovery information for a particular session key is evenly distributed among a large number of sessions.


Each expr can refer to variables bound in the current certificate or any previous certificate.

once a variable is bound, it remains bound for the rest of the certificate chain.


Since the role infrastructure of user permissions A is constructed from B and C, edges represented in B and C must be minimal satisfying Equation 2.

let the notation |M| represent the number of edges represented by a matrix M. the number of elements in the matrix set to 1, mij =1whereeach mij =1 represents an edge or a relationship between i and j.Using the notation, we have: Problem 2.


Given this, the probability that Requirement (2) is satis.ed, PS(2), is computed as follows: 1 PS(2) =Prob(tgA <tgV )+ Prob(tgA = tgV ).

(3) 2PS(2) is composed of two components; one corresponds to the event that the block containing TRA is .rst generated and the second to the event where the blocks containing TRA and TRV are generated at the same time, i.e., tgA = tgV .


Because data from untrusted storage is always fetched and stored in the form of a tree paths, we can achieve integrity by simply treating the Path ORAM tree as a Merkle tree where data is stored in all nodes of the tree (not just the leaf nodes).

each node (bucket) of the Path ORAM tree is tagged with a hash of the following form H(b1 b2 .


4.4 Malicious Users and Sybil Attacks While Buddies can measure, and optionally enforce a lower bound on, the number of users comprising a Nym s possinymity or indinymity set, Buddies cannot guarantee that all those users are providing useful anonymity.

if the owner of a Nym N has speci.ed a policy mandating a minimum buddy-set size of K, but up to F other clients may be colluding with the adversary, then N s owner may have to assume that its actual minimum anonymity set size may be as little as K - F , if all F bad clients happen to or somehow arrange to land in the same buddy set as N s owner.


CBC mode is better: it degrades more gracefully in the presence of repeated IVs.

if we encrypt two plaintexts P, P ' with the same IV under CBC mode, then the ciphertexts will leak the length (in blocks) of the longest shared pre.x of P and P ' , and nothing more.


CONCLUSION We have presented the design, implementation and evaluation of process out-grafting, an architectural approach to address isolation and compatibility challenges in out-of-VM approaches for .ne-grainedprocess-level execution monitoring.

by e.ectively relocating a suspect process from a production VM to the security VM for close inspection, process out-grafting e.ectively removes the semantic gap for native support of existing process monitoring tools.


In this paper, we describe how an eID architecture can be designed and implemented using TPM 2.0.

we make the following contributions: We provide the .rst accessible description of the TPM 2.0 authorization model.


However, the concept of trust and its implications are becoming more and more significant in today s information age where unfamiliar or untrustworthy systems communicate with each other in a distributed world.

trust has played an important role in the security world.


This is because the veri.cation checks that code follows the chunks speci.ed in the bitmap and each chunk is validated in a modular way.

if the attacker-provided code and bitmap pass the veri.cation, then the IRM s policy is guaranteed to hold.


The new pattern specifies that after matching a single white space, we start counting for [^n]{1024} no matter what the content is.

it is not hard to see that for every matching substring s that the original pattern reports, the new pattern produces a substring s that is either identical to s or is a prefix of s. the new pattern essentially implements non-overlapping left-most shortest match.


This results in correct decryption as long as d< log log q - (log log n + log N + O(1)).


Some works assume a .xed range for communication and interference, while others are based on concepts like capture threshold where the desired signal strength is compared with interference from a single node at a time, rather than cumulatively.

the latter model is used in ns2 which is the most common simulation tool.


However, for the purpose of labeling programs, the re-use limitation also requires changing the labeling of the variable inputs of f whenever f is executed on a di.erent set of inputs.

labels are useful to identify both concrete data items and variable inputs of programs.


3.5 Kernelization of WSP Formally, a parameterized problem P can be represented as a relation P .S * ×N over a .nite alphabet S. The second component is call the parameter of the problem.

wSP is a parameterized problem with parameter k, the number of steps.


One obvious choice of l can be derived from the security lattice L. In particular, note that L is .nite, hence the Hasse diagram7 of L contains a path of maximal length lmax .

one strategy would be to terminate the search for an approximate response if we do not .nd a path of length less than or equal to lmax between the nodes containing the relevant entities in the dominance graph.


To decode a barcode, Mobile applies the decoding and decryption functions in a reverse order and ignore the bit v1.

it .rst extracts the bit pairs from every Lblocks, and get the message m ' .


Intuitively, one read of 1000 consecutive bytes from a .le is equivalent to one thousand consecutive reads of 1 byte each.

consecutive .le operations of the same type (all reads or all writes) and network operations (all sends or all receives) are collapsed into one aggregate graph node.


An example of SysAuth catalog referring to the Position and Health streams is given in Table 1.

the .rst policy grants captains the read privilege on the position and id of soldiers belonging to their platoons, where this condition is modeled as a predicate (i.e., Position.


Some encryption schemes have additional properties.


In Figure 7, the non-aggregated attack graph in Figure 6 has been aggregated (automatically) to the level of machines and sets of exploits between them.

conditions for each machine have been aggregated to a single machine vertex (represented with a machine glyph in the figure), and individual exploits between each pair of attacker/victim machines have aggregated to single vertices.


In this work we present a new Attribute-Based Encryption scheme where private keys can represent any access formula over attributes, including non-monotone ones.

our construction can handle any access structure that can be represented by a boolean formula involving AND, OR, NOT, and threshold operations.


First, note that quadratic residues have at least four possible modular square roots.

given Xi 2 ,an attacker can guess Xi with at best a probability of 1/4.


We establish some basic properties of the interactive information complexity IC(f).

we show that IC(f) is equal to the amortized (randomized) communication complexity of f. Wealsoshowadirect sum theorem for IC(f)andgive the .rstgeneral connectionbetween information complexity and (non-amortized) communication complexity.


3.1 Formalization: Dynamic Graphs The dynamic graph is a simple generalization of the static graph {G(i) used in literature.

g = }for 1 = i = t is (V(i) a dynamic graph over t time periods.


Considered one at a time, these two aspects tend to cause a perceptual misunderstanding where the required computer skills are confused with the intentions of information operations and vice versa.

operations utilizing computers need to be based on knowledge and reasonable assumptions about what can actually be accomplished with computers.


In our construction we limit the vulnerability to such an attack by increasing the amount of time needed to compute the hash function.


Thus, (F, J, p¯i(0), p¯i) will be a valid forgery.

a can produce a valid forgery if it knows a.


While pi may be tempted to cache a ciphertext cj received from principal pj so that pi will never need to query pj more than once about any assertion within a single session, this is inadvisable because the same random value would be reused multiple times if cj was the encryption of a randomly chosen element of the message space.

reusing cj would not be indistinguishable from using a fresh element of the message space chosen uniformly at random.


Some vertices may not have any siblings; as they do not contribute to bandwidth overhead, we can conceptually remove them and connect their edges to turn the tree into a full binary tree.

it is well known that a balanced tree provides the lowest height among d-ary trees of a given degree d. the height of a balanced binary tree with n leaves is plog2 nl, which corresponds to the worst-case amount of unsigned hash values in the authentication information of a packet.


observed in their study of exploits destined for unused address space, emulating end-host behavior allows us to collect more session data from an attacking host [20].

completing the infection handshake will suf.ce to cause the attacker to transmit the shellcode.


The value of the function at this point is called maximum of that function.

each value in the graph is compared to its neighboring values, and if it is larger than both of its neighbors, it is a local peak.


Therefore, we can give a early warning of DoS attack, if the rise in CPU utilization continue for a period of time.

we can de.ne various states, based on CPU utilization and number of packets, through which a system undergoes to .nally reach in the state of DoS attack.


The fan-out wires in the circuit are given a single number.

if the outgoing wire of a gate feeds into the input of multiple gates, then all these wires are indexed the same.


Although the individual credentials needed to satisfy a policy can be hidden by using a HCsimpleE with credential indistinguishability, parts of the structure of the boolean expression of the policy may be learned by any recipient.

an unquali.ed recipient may be able to deduce that a message s policy is of the form ((X AND Y )OR Z)even though he can t decrypt any part of the message.


We de.ne Lx = {y .X : y< x}and vx = {y .X : x<y}.

lx is the set of immediate children of x and vx is the set of immediate parents of x.


In this way, at the same time the CA will no longer be a bottleneck and OBUs will not have to download the entire CRL.

the used perfect k-ary trees are based on the application of a duplex construction of the Secure Hash Algorithm SHA-3 that was recently chosen as standard [3], because the combination of both structures allows improving efficiency of updating and querying of revoked certificates.


The basic idea of such relationship-based access control mechanisms is to decide distinctly privileged user groups by tracking the existence of relationship of particular type and/or depth between the access requester and the target resource or its owner.

carminati et al [7] identi.ed aggregated trust value to denote the level of relationship between users, and utilized trust metric along with relationship type and depth on a path between users as decisive factors for access control.


A common technique for authenticating devices is to enter the same PIN code into the involved devices, like a Bluetooth passkey for pairing, but such scheme requires the devices to have a number input interface.

smaller and specialized devices (like GPS loggers, portable MP3 players, etc.)


For example, the heuristic patterns of click-points used in [10][11] or the first-order Markov model used in [8][9] can be applied to significantly boost our attack s success rate on PassPoints.

when these attacks are combined with ours, they will lead to a dramatically improved success rate on guessing PassPoints passwords.


(1) w .StprS* (Sw) d d Here, prS* (Swd)denotes the total weight on the coset Swd.

prS* (Swd)may be viewed as the probability that a passkey ensemble drawn from the distribution W belongs to L the coset Sw, i.e., prS* (Sw):= pr(wc).


A developer might avoid these drawbacks by choosing the second option, but this comes at the cost of trusting the provider of the code.

the provider has complete control over the content that is served to the user of the web application.


Even when a monitor observes network traf.c between application components, if that traf.c is encrypted, the monitor is unable to detect tagged data.

with HTTPS client connections, socket-level ingress monitors will not observe tags.


Our extension is based on one important requirement of interorganizational workflows: the autonomy of participating organizations should be honored not only during the design phase but also during the runtime (execution) phase.

different workflow designers may work on different portions of an inter-organizational workflow during the design phase.


There are also three assumptions as to how the EDI transmitted data arrives no loss of confidentiality, integrity, or availability [9].

the information is received just as it was sent, and has not been tampered with by an unauthorized source.


In particular, we require an e.cient and system-centric monitoring that controls communication channels in Android s middleware and in the Linux kernel, and tackles the known confused deputy attacks without false positives, but is also .exible enough to cover future privilege escalation attacks.

our contributions are the following: We present the design and implementation of a security framework which extends the Android s reference monitor concept at both middleware and kernel level, that monitors communication links between applications and veri.es them against rules de.ned in a security policy.


Table 2 reports the number of SK-DNSSEC (which is abbreviated to the shorter SK ) operations that can be computed per second on a Pentium III (800Mhz) machine.

creating a SK authoritative answer requires the name server to .rst open and verify the symmetric certi.cate sent by the resolver and then compute a MAC over the answer.


In this work, we consider the identity-based attack can be present at any time.

di.erent from the previous work, which only considers the presence of such an attack during the authentication phase, we take the view point that the identity-based attacks could be present at any time in real-world scenarios even when building pro.les for legitimate users.


We treated IdPs and RPs as black boxes, and relied on the analysis of the HTTP messages passing through the browser during an SSO login session.

we traced the information .ow of SSO credentials (i.e., data used by the RP serverside program logics to identify the current SSO user) to explore potential exploit opportunities.


We will also achieve a factor f computational speedup.

when the optimization is applied to both schemes, the ratio of the computational overheads will remain the same.


In this paper, we show that this belief might not be true in certain aspect.

we show how we use publicly available data from Facebook to infer users interests that are usually only on their personal pro.le pages.


Because the bits of the protected content reach and physically stay on the user s machine, the protection of these bits is only as strong as the extent to which the DRM client software can protect itself.

although the bits are usually in encrypted form and accessing the bits is enforced by the rights policies, the client software must be tamper-resistant so that it is difficult for an attacker to modify the rights enforcement code of the DRM client software.


The server can build a circuit that computes a function other than f, we denote the function computed by the circuit as f ' .

because f is the server s private input, it is essentially same as the server inputs f ' instead of f. such adversarial behavior in the real model can be simulated by the execution of computing f ' in the ideal model.


In addition, it operates under a second reference monitor that blocksallbuta small setof systems callsgoverningI/O ports, memory, and IPC.

the reference monitor only allows sending and receiving packets to and from a particular IPC channel connected to the web server process.


4) trusting oneself implicitly can be assumed only in the intention dimension of trust.


AType 1 constraint (., s, s1)is satis.ed by a plan a if (a(s),a(s 1)) .. and is not satis.ed ( violated ) otherwise.

(., s, s1) is violated by a if (a(s),a(s 1))... Equivalently, a constraint (., s, s1) is violated i.


For instance, the fact that an individual receiver does not pay anymore its subscription fees should not impact other receivers.

such an event should not imply any re-keying operation, for those operations are either impossible or very costly in terms of bandwidth in a pure broadcasting scenario.


We construct a Schnorr attacker F that uses A as a sub-routine.


E(I)where E(I)is the set of edges of the subgraph I of b G that is induced by the vertices in P .R1 .... .Rn.

g is similar to a subgraph of Gb, except with sessions in place of users, and the edges induced by the vertices that are relevant to the sessions.


While lazy enforcement can match .ngerprints once and for all, before commit, eager enforcement checks for a match on every security-relevant access.

the x11perf/create benchmark creates and maps several hundred subwindows; with eager enforcement, each of the create and map operations entails .ngerprint matching and policylookup, which resultsinavery signi.cantslowdownofWeirdX.


In addition, a client may invoke other methods, but only via methods to which he is authorized.

if a client is authorized to invoke m1, and in its execution, m1 invokes m2, then this is allowed even if the client is not authorized to m2 via annotations.


At a high level, this score is computed by comparing the parameter strings of each system call and the system call that immediately follows it; the more different they are, the lower this score.

the similarity between two sequential calls is computed as follows.


4.1.2 Detailed Design The design of SYSVMI is based on hardware virtualization.

it achieves coarse-grained execution context identi.cation and performs syscall-level reactive tampering.


the structural model of learning can be likened to a musical instrument and the process of learning to a musical score that depicts a succession and combination of notes played on the instrument over time Since each Information Assurance class contains students utilizing each learning style, Kolb s model indicates that moving the class through each quadrant should optimize learning.

optimizing the learning process requires an appropriate succession and combination of learning activities.


In fact, the SxC tasks executed on the mobile device, i.e., contract validation and model checking, are non trivial.

model checking requires heavy computation which may take long time and rapidly exhaust the device resources.


As the research .eld matures, we feel it is time to step back and take stock of some of the central questions in role mining.

what is role mining or what should it be?


Given that we are considering only threat models that require adversary persistence, system compromise is only possible i. there has been a succession of vulnerable platforms played by the defender.

compromise at time k is de.ned as a Boolean: k k-1 k-K+1 1 v(p ), v(p ), .


Our crawler allows us then to match the identi.er to login names of users that did not yet choose to change the default setting of their pro.les, so as to not display the login names.

even Number of profiles (Millions) 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 Profiles Numeric IDs Logins     5 10 15 20 25 30  Time (Hours) Figure 2: Cumulative number of gathered pro.les in function of crawling time.


Our experience indicates that this algorithm is generic and can be readily extended to handle information leaks that disclose information that directly concerns the user s identity, such as their recent calls or the list of accounts.

the general approach we take essentially employs backwards slicing to determine where the arguments to a network call originated from.


TZ-RKP adds overhead to a small portion of these operation.

operations related to memory allocation that involve translation table updates, which are intercepted by TZ-RKP.


RBAC by itself only speci.es the structures to store access control information, but not how to manipulate these structures, which are speci.ed by administrative models.

only the set Qof states is precisely de.ned, the set wof state-transition rules is not.


This paper proposes a statistical design of experiments approach that will enhance the quantitative aspects of the risk assessment exercise and will make risk assessments smarter, more precise and more efficient.

our paper demonstrates that a Plackett-Burman design can be used to: (a) identify the subset of security controls that are critical to the enterprise; (b) determine the configuration of these controls; and (c) quantitatively analyze the impact of security enhancements.


In this example, Bob owns and brokers all access to the shake table, and makes and directly signs his own authorization decisions.

alice will be able to access the shake table if Bob signs auth(shaketable, Alice) is true at Bob.


We con.rm these results in the online survey study (study 2).

we found that half of the survey participants (379, 52%) used a locking system.


The ROC graph showed that two classes were cleanly separable using the distance measure.

when the threshold was lower than the lowest non-variant distance, then precision and recall were perfect, except in those cases where the threshold was also less than the maximum distance for the variants, in which case recall was less than perfect.


However, as we mentioned before, wireless sensor network inherently has resource constraint such as low computation, low memory, short communication range, and low batter life.

the recourses for the security issues are few available.


Specifically, Threat 1 can be solved by using access control mechanisms like [2,6,15] (both in the VMM and in the kernel) and end-to-end encryption mechanisms.

[6] protects a mobile device against this threat by running two isolated domains, called Secure Domain and Normal Domain, on top of the VMM.


We clarify that these are local references to the cosigners partici i pating in this protocol instance.

(each signer in this h Pr J = i : hi,...,hq .H ;(J,s) .A(x,h1,...,hq ; .)


2.1 Environment The MANET environment is generally considered as a peer network.

no node should be trusted more than others.


When an agent migrates or terminates, all of its allocated resources should be reclaimed as soon as possible.

all threads of the agent shall be stopped and memory allocated by the agent shall become eligible for garbage collection.


For copydependencies, the equality that must hold is: I( ;7) = I(y;7) Computation dependency: If a data object y is computed as a function of one or more other data objects, e.g., w and x, its mutual information with the taint source depends not only on the mutual information of the inputs with the taint sourcebut also on the mutual information between these inputs(J(wi x)).

if two inputs are based on different source data we should add their taint values, but if there is the minimum joint entropy between them we should take the maximumvalue(max{J(wi T),J(xi T )})instead of addition.


If not, however, we now choose rj ,tj , and skj uniformly at random (rather than computing these values as the output of Hk(C.,p)), and then continue as before.

if there is a subsequent Send3 query using the correct value of tj then the server instance .j accepts and outputs the U. session key skj := skj .


In order to measure the integrity of the hypervisor, the measurement agent needs to access the hypervisor s code, data and CPU state.

it needs the VMX data structures, which contain contextual information essential to integrity measurement (e.g., current VMX operation, the hypervisor s VM exit handler and its CR3 register value).


Authentication is how users prove their identity assertion.

it is a presentation of secret that only the owner must know and the system can then verify the identity with.


For code size, IBM software TPM 1.2 implementation3 takes 3.28MB code space, in which 225KB code is used for DAA.


The adversary in our model has full privileges in controlling the software system on H, except the secure kernel and TCG software.

the adversary is able to modify and manipulate all the programs and data .les on H for her own bene.ts.


Since the attacker s SE, despite its knowledge of PINSE+RootID , is not able to calculate the shared secret, it cannot establish the RootID-SE-Channel.

the RootID will not accept any connection attempt from the attacker s SE, e.ectively preventing the relay attack in Figure 5.


We do not expect the malicious app will request any sensitive permissions during installation, which means it will only rely on vulnerable apps to accomplish its goals: either steal money from the user, gather con.dential data, or maliciously destroy data.

we limit the attacker to only unprivileged third-party apps to launch their attacks.


INTRODUCTION Does it make sense for an application to self-encrypt an encryption key?

if Es represents an encryption function with key s, would it ever be the case that an application Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for pro.t or commercial advantage and that copies bear this notice and the full citation on the .rst page.


Our further investigation (omitted due to space limit) indicates such stability is not static, but dynamic.

the live bots are being strategically rotated with a short online duration to maintain such dynamic stability.


Di.erent from the non-cloud computing, resources impose very complex dependencies between each other in the cloud computing since they are multi-layered.

one resource may be built upon another, which can even be built upon another.


Our earlier analysis indicates that it is very dif.cult for the adversary to prevent two noncompromised sensors from establishing a pairwise key.

the grid-based scheme is intrusion tolerant in the sense that even if the current pairwise key between two sensors are compromised, as long as these sensors are not compromised, they can reestablish another pairwise key with a high probability.


Users can install and execute almost arbitrary applications on these devices.

smartphones are often used for different tasks with di.erent security requirements, e.g., for playing games, taking photos, running private online banking, or even accessing a corporate network.


Within the same framework, we put forth a coding theoretic necessary condition for a traitor tracing algorithm to exist.

we explicitly show that any ExEG scheme that fails this condition is susceptible to the construction of an untraceable pirate decoder.


Accuracy -Since the proposed protocol is probabilistic in nature, we include a checking step to securely verify whether the result is correct or not.

the steps involved in the proposed protocol can be run in an iterative fashion until the result is correct.


If the false positive rate is decreased, typically the anomaly error threshold is increased.

if the horizontal line is moved up, more attack points will be missed by the IDS.


To make sure dummy text messages are consistent with the previous topics in users communications, one could use text document analysis techniques, such as constructing and applying topic models [16].

we propose using the Latent Dirichlet Allocation (LDA), a generative model in which any speci.c document is viewed as a mixture of topics.


There is an additional restriction on where we can place the end of the data region, which is described below, but the idea is to leverage this ability to control where in a program s execution sYSMALLOc() is called a subsequent time.

the program makes a number of calls to malloc() and free() and one of the buffers allocated by malloc() is passed to read().


BLOCK GENERATION IN BITCOIN To generate a block, peers work on solving a PoW problem.

given the set of transactions that have been announced since the last block s generation, and the hash of the last block, Bitcoin peers need to .nd a nonce that would make the SHA-256 hash of the formed block smaller than a 256-bit number (target ): SHA-256{Bll || MR(TR1,..., TRn)|| No}=target , (4) where Bll denotes the last generated block, MR(x)denotes the root of the Merkle tree with elements x, TR1 || ... || TRn is a set of transactions which have been announced (and not yet con.rmed) since Bll s generation, and No is the 32-bit nonce.


PA]} GTRBAC Model [4] The GTRBAC model incorporates a set of language constructs for the specification of various temporal constraints on roles, including constraints on their activations as well as on their enabling times, user-to-role assignments, and permission-to-role assignments.

gTRBAC makes a clear distinction between role enabling and role activation.


V (x1, x2) = ej }, where ej = sup ß(x, x ' , t).

t.[tj-1,tj ],x .Bd(x) ej is an upper-bound on the value of V for two executions .x and .x starting from within Bd(x) over the time interval [tj-1, tj ].


By using the same role de.nitions, we can limit the access to a speci.c set of accounts, by turning the event into a personalized one.


This iterative process can be readily performed by machines through computing low-level features of the image.

a cognitive decision about whether both sides of a boundary are correlated or not can be approximated by detecting similarity of textures and continuity of traversing objects.


UMTS maintains the same challenge and response method as its 2G predecessor, GSM, to facilitate generation migration.

during registration, an HLR prepares and sends a list of authentication vectors (AV) to a VLR (see lines a2to a12 in Figure 1.)


First, the effectiveness of EV as an example of visual security depends on users who should be ruled out in security-critical operations [1].

some researchers try to exploit the visual indicator by picture-in-picture attacks [15].


We detect the beginning of the piezo beep in the signal using signal-processing tools.

to determine if a certain signal region is a potential piezo beep, we examine the signal using a window size of 67 samples and perform FFT to produce the spectrum of each signal region.


This paper presents the .rst systematic design of vulnerability signature based parsing and matching engine, NetShield, which achieves multi-gigabit throughput while offering much better accuracy.

we made the following contributions: (i) we proposed a candidate selection algorithm which ef.ciently matches thousands of vulnerability signatures simultaneously requiring a small amount of memory; (ii) we proposed an automatic lightweight parsing state machine achieving fast protocol parsing.


In the real world, however, the secure computation of init SMC returns secret shares of S T to the parties.

the secure computation implements the following (randomized) function after computing S T : choose random c1,...,cN-1 .


For each point-and-click action, we measure the amount of time between the end of the movement and the click event.

this metric measures the amount of time spent pausing between pointing to an object and actually clicking on it.


The reason for performing the veri.cation process more than once is to tolerate packet losses.

by performing the veri.cation process w times, up to a sequence of w packet losses can be tolerated, where the value of w depends on the average packet loss rate of the network.


These networks help to circumvent online censorship and protect freedom of speech, but represent a mixed blessing for the providers of online services.

anonymous access can expand the range of users that contribute to an online service, but it can also allow misbehaving users to abuse the service in a way that makes it di.cult to hold them accountable.


Furthermore, as we see in the bottom bars of Figure 1, security awareness also diminishes.

top popular sites seem to restrict their policies more carefully than not so popular sites only 16% are weak cases for the Top 100 vs. almost 50% for the Top 100K sites.


However, it could also be the other way around: case (ii).

method B is wrongly rejecting a pattern from the correct user, this leading to an increase of theFAR.


The identity tokens are needed since the authentication and veri.cation of identity are separated in A2.

the authentication is only performed at the time of creating a new process.


6.1 Initial Considerations The goal of our experiments is to evaluate the proposed IDS.

the amount of raised detections and false positives.


This way, our proposal also provides an implicit-indirect entity authenticity veri.cation because only a particular entity, with the appropriate pre-shared and updated key states can generate the required key for a given message exchange session.

by verifying the integrity of the key, we can authenticate the entity.


However, one of the most important challenges of information sharing is how to assure its security [6].

the parties sharing the information should be protected according to security policies which could be preset explicitly, though policies are sometimes hidden in application scenarios.


Physical security measures were also lacking.

the ES&S scanner lock was easily picked with a paper clip during our tests, while the unpickable lock on the Sequoia scanner was bypassed by removing a few screws and pulling out the lock cylinder from the scanner s chassis by hand.


If all costs for TIS-based as well as TIL-based implementations are properly calculated, we believe that the latter will turn out to be considerably higher.

we believe that costs of all multiple partial and separate TISes will significantly exceed the costs of a single comprehensive TIL-based solution.


A naïve way to implement a DFA-based regular expression matching engine is to treat multiple DFAs as a single NFA (with a constant active set size).

iNFAnt can be used to support multiple DFAs.


A strong integrity-preservation policy, such as the Biba s strict integrity policy and the low-watermark policy, will ensure that all executions are integrity preserving.

this means that low-integrity data and programs cannot in.uence the contents of integrity-critical (data or program) .les on the system.


2.1 Java for mobile phones The J2ME introduced by Sun Microsystems in 1999 was meant for devices with low computational power and memory.

this applies to PDAs and mobile phones, but also to other embedded systems such as VoIP phones or sensors.


The earlier form is actually a special case of the extended form, in which all the antecedent events and conditions are associated with the same time instant.

for any t, E1 att,.., Em att, C1 att,.., Ck att .


To address such an issue, we recently proposed a multiparty access control (MPAC) model [22] to capture the core features of multiparty authorization requirements, which have not been accommodated by other access control systems for OSNs (e.g., [10, 11, 16, 17]).

we introduced a systematic con.ict detection and resolution approach [21] to cope with privacy con.icts occurring in collaborative management of data sharing in OSNs, balancing the need for privacy protection and the users desire for information sharing by quantitative analysis of privacy risk and sharing loss.


It is important to point out that the number of bits required to represent the data depends on many factors and it can change with each training set.

the bitsize for the coe.cients can be chosen so that the computation precision is similar to that of a plain implementation.


We then discuss di.erent measurements that serve as the basis for detecting a jamming attack, and explore scenarios where each measurement by itself is not enough to reliably classify the presence of a jamming attack.

we observe that signal strength and carrier sensing time are unable to conclusively detect the presence of a jammer.


However, in comparison to OpenID, InfoCard is a heavy-weight protocol.

users need to install an identity selector and relying parties must have a valid SSL certi.cate con.gured to provide secure channels when communicating with identity selectors.


The de.nition of privacy in these models are as follows: retrieved data from a database should not reveal any extra information to the querier about the record owner compared to simply not letting him/her retrieve the data, even if the querier already knows some information about the owner from separate resources [42].

these models aim to decrease the probability of identifying individuals even though his/her speci.c attributes are included in the information retrieved form a database.


However, we can still alarm all these cases.

our contributions are as follows: We explore three styles of privilege-escalation malware transformation techniques based on their di.erent functionalities.


Chroma, also called pitch class profile (PCP), is a frame-based representation of music signals, where the full spectrum is projected to 12 semitone classes included in an octave to reflect the distribution of music notes [12].

a 12dimensional Chroma feature of a music signal is calculated as below, ... .


works o.ine), our prototype is implemented in online mode.

the detection is performed at the same time when the MSIE handles the page.


A policy for a web browser expresses what executions of the browser are allowed and which executions are not allowed as seen by an external observer.

a policy on a web browser is a restriction on the input/output behavior of the browser.


We then show an impossibility result indicating that a sim- ilar equivalence does hot hold for Multiparty Computation (MPC): we show that even if protocols are given black-box access for free to an idealized secret sharing scheme secure for the access structure in question, it is not possible to han- dle all relevant access structures efficiently, not even if the adversary is passive and static.

general MPC can only be black-box reduced efficiently to secret sharing if extra properties of the secret sharing scheme used (such as linearity) are assumed.


Although the bene.ts of cloud computing to enterprise consumers and service providers have been well explored, its effect on end users, applications, and application developers is still not clear.

research is needed to explore the new design models and unique requirements of cloud aware applications in order to leverage their full potential.


These points are being considered to be secured in the project, especially during the implementation of biometric algorithms.

the prototype had implemented a method to protect the biometric references, complemented by cryptographic mechanisms to secure the storage and to check the integrity of the prototype components.


Considerasimple system withtworequest types A and B (for clarity we index request types with letters), and consider a mitigator with these prediction functions p(N, r) for N =1: Assume the following input history: (2,A), (4,B), (6,A), and (30,B).

two inputs of type A arriveat times2and6,and two of type B arrive at times4and 30.


This enables to control what has been signed, but not how many times.

the proxy may have unlimited authorization to sign documents of a given kind.


The attacker can attempt to exploit known vulnerabilities in machines on the internal network.

the attacker can attempt to exploit the client machine itself.


However, this method would suffer by the other highlighted problems.

it is not transparent to the user and, most importantly, it cannot be leveraged by the technologies already available in smartphones.


=(u, u 1) .U ×U :(u, u 1)...   AType 2 constraint (., s, S1), S1 .S is violated if (., s, s1) is violated for all s 1 .S1.(., s, S1) is violated i. the constraint expression (., s, s1) si.Si is satis.ed.


The TCG-MPRA speci.es that Mandatory engines are required to be supported by a Mobile Remote owner Trusted Module (MRTM) which supports secure boot and does not permit a local Operator to remove the stakeholder from the engine .

the security of a mandatory engine cannot be compromised by any other local or remote stakeholder of the platform.


As detail in [21] and [22], RSEP contains the necessary functionality to remotely monitor assets, systems, and currently supplied protection mechanisms, whether active or passive, in a timely manner.

secure, timely, precise, and e.cient monitoring of critical information systems and infrastructures can be achieved with this concept.


CONCLUSION Existing smartphone operating systems, such as Google Android, provide no data and application isolation between domains of di.erent trust levels.

there exists no e.cient solution to isolate corporate and private applications and data on Android: the existing security extensions for Android only focus on one speci.c layer of the Android software stack, and hence, do not provide a general and system-wide solution for isolation.


In the scheme we propose, we take advantage of an important property of NH in order to improve its online performance.

if the universal hash function is proved to be additive-universal, then adding a random mask to the hash result will produce a provably secure MAC.


Informally, .i and qi describe the current instruction and the contents of memory for a single execution of a program, and capture the state of the system just before executing the encrypt or decrypt primitive.

if the execution of the program is suspended for a brief time, .i,qi would describe a snapshot of the stack, the value stored in the instruction pointer (IP) register, the values of all dynamically allocated variables (i.e., those on the heap), etc.


6.4 Description of the Scheme We use traditional multiplicative group notation, instead of the additive notation often used in elliptic curve settings.

if g is an element of G1, we write g x to denote exponentiation by x .


The Impromptu prototype, an application for ad-hoc peer-to-peer file sharing, was developed as a testbed to explore both the concept of integrating action and configuration and the concept of dynamic visualization of activity.

impromptu was not designed to be the best file sharing interface, but simply an application with which we could explore our design principles in a scenario that would be comprehensible to test subjects.


Because of the support of e in class Ck is supp2, we think the score contributed by a single EP is that the odds multiplied by supp2.

the score of a single EP is (GrowthRate/(GrowthRate+1)) ×supp2.


Robustness Even though the primary purpose of our tool so far has been to evaluate existing .ows (a scenario under which we don t need to worry about malicious code trying to subvert our system), our framework does in fact protect its internal data structures from being maliciously modi.ed.

our tool disallows a user JavaScript program from referencing any of the variables and .elds used for taint tracking such as TSET.


As Fi(v) is the probability that Pi s risk appetite, 1 - Ei = v, F can be expressed as (see Appendix A for proof): Fi(v)= v (3) Our second IDS accuracy function, F ,is representative of real IDS functions.

it is impossible to determine with complete certainty that a node is malicious (see Equation 4).


The library de.nes default sources and sensitive sinks for the Google App Engine framework.

it provides a middleware to intermediate between the web server and the application so that data obtained from the server gets automatically tainted as well as checks if the data being sent back is sanitized.


On the one hand, Web Services protocol engines partially act statelessly by only reacting upon incoming messages without considering the history of the current protocol run.

they might discard some or all of their knowledge about previously received messages.


All memory error exploits reported so far have been based on pointer corruption.

these exploits use a software vulnerability (such as out-of-bounds array access) to change a securitycritical pointer with an attacker-provided value.


In the context of ongoing international standardization e.orts like ISO TC 22/IEC TC 69, it is manifesting that in the future certain roles of actors in the backend system will be concerned with security and privacy-related processes.

for the charging management of EVs, the draft standard ISO/IEC 15118-1 [7]de.nes actors and protocols to perform load management, billing and clearing, as well as certi.cation.


Assume that the worm in question is a random scanning worm.

on each attempt to propagate, an instance of the worm will randomly select one host from the address space, and infect that host if it is both vulnerable and uninfected.


These indices have no certi.ed relationship with the public keys.


Finally, we provide a case-study with an autonomous vehicle, called the LandShark [1], to illustrate the e.ectiveness of the best of these methods.

we consider four speed sensors, two of them also measuring position, that provide the controller with twodimensional polyhedra.


Such a BN-based model allows propagating probabilities of an attacker reaching each condition.

we are interested in the goal state (the .nal conditions), which can be used as an indicator about the overall security of the network.


we prove that our new algorithm is secure against the Bellcore attack [4, p.311].

the paper claims security against Fault Models #2, #3, and #4.


We have discussed several issues related to validation of the user supplied credentials for ensuring secure and authorized information access.

we have discussed trust-based validation of credentials in a decentralized environment with no central certification authorities which everybody trusts.


By preventing the exposure of the key outside of the processor, an adversary is unable to read and store the key.

the key can only be used once and is immediately destroyed.


The second is to be able detect the presence of resource usage fraud within an inspected dataset.

the detection techniques characterize the level of consistency of request semantics relative to normal activity as opposed to factoring in volatile request volumes.


Brute force attacks are supposedly thwarted by constantly randomizing the address-space layout each time the program is restarted.

this technique seems to hold great promise in preventing the exponential propagation of worms that scan the Internet and compromise hosts using a hard-coded attack [11, 31].


Given the lack of perfect ground truth, to measure false positives we check whether the malware can establish successful communication with the detected remote servers and whether a server s response successfully triggers the malware s malicious logic.

for each detected server, we conduct another round of veri.cation by redirecting the malware s request to the detected servers and monitor the malware s execution afterwards.


= 1] Experiment 1 In this experiment we modify the way the challenger constructs the challenge ciphertext.

it constructs the challenge ciphertext as c = ((1 + N)mf ) · (r)Ns mod Ns+1 where r .


(Essentially, one of the browser-based protocols could be used.

certain messages in these protocols are similar to attribute certificates; only the proposed message formats are different and based directly on XML.)


IDENTITY BOXING An identity box is a secure execution space in which all processes and resources are associated with an external identity that need not have any relationship to the set of local accounts.

within an identity box, a program runs with a high-level name such as /O=UnivNowhere/CN=Fred rather than with a simple integer UID or account name.


We note that, as HMQV, the subgroup test of peer s DH-component can be waived (but still with the supergroup G ' membership check), if no DH exponent or component is pre-computed and thus leaked.

in this case, the black-box analysis of OAKE does not rely upon such a test.


However, we believe that the lack of these values is partly due to the absence of incentive for de.ning them.

collecting such values is pointless without tools to analyze and treat them.


While a driver s license, Social Security number or credit card number may be stolen secretly and used to impersonate someone, a biometric can be linked only to a specific individual (with only small levels of false identifications) so that fraud may be discounted.

if a biometric can be traced to one person, 77 it must be from that person.


4.3.1 Flexible Path Linking Rules These rules allow null cross links to exist and are used as a methodology for open interoperation.

if a null cross link exists between two domains, then such domains are willing to interoperate with one another through other domains as long as a secure path between them can be established.


Playground had automatically created accounts with these services.

we found emails from 34 di.erent services.


The contribution of this paper is overcoming the above limitation.

by exploiting the unusual feature of the pdf standard [19] which tolerates the presence of the header within the .rst 1024 bytes, we are able to enhance the attack in such way that the two .letypes, namely pdf and tiff, embedded into the polymorphic .le are both extremely safe allowing the attacker to produce a fake document that appears in a format widely accepted in the context of e-government activities both whenever it is signed and whenever it is fraudulently exploited.


Unfortunately, traditional key agreement models such as those following the schema set out by Bellare and Rogaway [4] have been shown to be less useful to analyze deployed protocols.

they demand for session keys to be indistinguishable from a random string.


We adopt a one-dimensional, linear, discrete view of time, with a beginning and no end point.

the model of time that we choose is a total ordering of time points that is isomorphic to the natural numbers.


First, TAHO E currently does not analyze all hooks in LSM-SELinux.

lSM-SELinux has several hooks to allocate and free data structures internal to the kernel module (which implements hooks).


Figure 1(b) shows the results of the .ve patterns of User 2.

the x-axis (of the graph) represents the time (starting from the moment the call is initiated), and the y-axis (of the .gure) represents the corresponding measured acceleration (on the x-axis of the phone).


Utilizing 2RPC, where only differential path of 1R and 2R is considered, will reduce the number of suf.cient conditions.

generating a 2RPC needs much less queries than generating a real collision.


Hyper-V uses a boot model for guest VMs that mirrors the way in which physical machines boot.

hyper-V provides a virtual BIOS that expects the OS to boot from a legacyvirtual IDE.


The ROK property o.ers no additional security against such an attack.

we are making no special claims of cryptographic prowess.


We see that the rate used by DLP converges to 1 when the delay constraint increases.

dLP does not introduce too many dummy packets when the system has a large .. value.


In Figure 7 we show a sanitizer speci.cation that maps functions to contexts.

two sanitizer functions, EcmaScriptStringEncode and HtmlAttribEncode, are applied for the JavaScript string context and the HTML attribute context, respectively.


nShield should provide the host devices unintermittent protection against passive eavesdropping.

the down time of protection caused by battery depletion should be minimized.


E.ectiveness against anti-forensics tools: Although forensics techniques can collect signi.cant amounts of information, investigators must be careful to ensure the veracity and .delity of the evidence collected because antiforensic techniques can hide or intentionally obfuscate information gathered.

rootkits can be used by hackers to hide the presence of malicious software such as bots running in the system.


4.3 Booking Protocol In this section, we address the .rst characterization of realistic mobility model.

there are some isolated nodes that meet all the other nodes with a very low frequency (compared to the meeting frequency the other nodes have).


A key-like decryption blackbox D in our setting is viewed as a probabilistic circuit that takes as input a ciphertext CT and outputs a message M or ., and such a decryption blackbox does not need to be perfect, namely, we only require it to be able to decrypt with non-negligible success probability.


Once a warden begins interacting with a station, it and any attached prover are isolated from the outside world.

the veri.er monitors to be sure that no external communication (wireless or otherwise) is occurring while the protocol is being executed.


Furthermore, we present the .rst evidence that the insider threat is a real problem impacting smartphone users.

12% of subjects reported a negative experience with unauthorized access.


It is desirable that this .nal conclusion is not precise, again up to some .xed parameter.

an adversary should not be capable of determining the destination of a user from his original position and his location updates on the route.


Interestingly, the SURF-based and WarningBird-based classi.ers detect redirection graphs as malicious that SpiderWeb misses, and vice versa.

spiderWeb fails in detecting .ve redirection graphs in Tr4 as malicious.


CONCLUSION The results of our study suggest that insiders are an important threat, and they impact smartphone users today.

we found that users are concerned with insiders, and more than 12% of them experienced unauthorized access of their data or functionality on their smartphone.


Following the approach of Steiner [27], we analyze the security of our protocol in the framework for asynchronous reactive systems proposed by P.tzmann and Waidner [23].

we .rst specify the target behavior of a GKE protocol in terms of an idealized service, and then show that our protocol has the same input-output behavior as this idealized service.


Over time that chunk will be moved to new blocks as the result of garbage collection with each subsequent block having a higher sequence number.

there may be a signi.cant difference between when a chunk was written to a given block and when the chunk was originally written.


Note that the bound on CL-resistance we establish holds for a certain range of parameters.

as long as the number of target VMs t is at most //e and the number of attack VMs q is less than / · log(t/2).


C is a commitment of a value x with opening r. Pedersen Commitment is perfect hiding and computationally binding.

even a computationally unbounded receiver cannot learn anything about the value committed from the commitment.


The solutions Jand Jm2in Example 2.2 are not y universal.

there is no homomorphism from Jto J and there is no homomorphism from J2to J.


Since VNET is driven by humans, we propose using social networks for setting up trust among vehicles.

the social network is very useful when the VNET application is running among people and in the scenarios when the roadside network infrastructure is not available or under attacks.


PRIVACY LEGISLATION To visualize private information flow in order to identify vulnerabilities that lead to non-compliance, one needs to understand which vulnerabilities pose risks of contravening privacy legislation.

it is necessary to know what privacy legislation requires for preserving personal privacy.


One property of UNF terms is that if a userset X satis.es a term f under con.guration (U, UP),then X also satis.es f under (U ' , UP ' ),where U .U ' and UP .UP ' .

because a UNF term does not have the negation operator, then if X satis.es the term under a con.guration, enlarging the con.guration will not make X fail to satisfy the term.


Section5discusses issues in enforcing inter-task properties.

we formally propose the task-allocation problem, and investigate its tractability.


To make this idea work, we need to address a few technical challenges.

searching across all 340 million tweets daily is impossible.


This requires further research both on the methodology side and the technical side.

the relation between cultural norms and access norms could be further explored, in terms of a precisely described method for translating one into the other in the context of security.


In P 64, the outcome is stored in memory pointed to by the qhasm variable rp.

the limb ri of R = r0 + 264 r1 + 2128 r2 + 2192 r3 corresponds to the qhasm expressions *(uint64 *)(rp + 8i) for every i .


According to simulation results, the proposed intrusion detection technique has substantiated diverse success rate at each layer of the protocol stack.

the proposed methods are successful at the application layer, quite good at the network and MAC layers and rather weak at the physical layer.


We have also explored the co-existence of resiliency policies with static separation of duty (SSoD) policies.

we have presented several computational complexity results on checking whether a set of resiliency policies and SSoD policies are consistent.


Our prototype provides all the features required for deployment.

we implemented the following parts: (a) the communication .ows and processing logic for the message exchanges presented in Section 4, (b) the ILS process with the fully implemented Integrity Tree, and the capability to publish the information required for its consistency checks, (c) the validator process, which monitors the ILSes and publishes misbehaviors, (d) the CA process that includes the validator s role with the additional ability to produce on-line con.rmations, (e) the client process, i.e., a browser extended with support for full ARCert validation, (f ) the protocol for accountable synchronization, and (g) the domain tool, which can register, update, revoke, recover, and con.rm ARCerts.


One of the common reasons mentioned by the participants for not opening or for deleting the phishing-noaccount emails is I don t have an account with this organization.

one of the participants mentioned, I don t have account with Barclays, how did they get my email address, and why are they sending emails asking me to update my information.


If all policies are found to be NotApplicable to the decision request, then the policy set shall evaluate to NotApplicable .

grant takes precedence, regardless of the result of evaluating any of the other rules in the policy.


5.1 Bitcoin protocol enhancement proposal In [3, Section 3.2], the authors propose to modify the Bitcoin protocol so that in order to create a transaction txnew that redeems an unspent output i of an earlier transaction txold, this output will be referenced in txnew via (SHA256d(txsimp), i) instead of old (SHA256d(txold), i).

the id of txold shall be desimp rived from the simpli.ed form txold , i.e., the form that excludes the input scripts which are required for txold to become valid.


INTRODUCTION Computer Network Defense (CND) operations have attracted increasing attention in recent years.

there is growing interest in Response Actions (RAs), i.e., design of system mechanisms that can react to vulnerabilities and exposures and deploy countermeasures in real-time.


These three are the most important parameters determining the e.ciency of broadcast encryption schemes.

the main issue in this paper is to minimize the transmission overhead with practical computation cost and storage size.


Second, and more seriously, while taint propagation is a useful tracking technique, it raises problems in current operating systems because of implicit sharing.

all users and processes share a single common .le-system namespace.


We share with more recent work on access control models the insight that security policies need to be flexible and accommodating.

the domain and type enforcement model [1, 7] has been proposed as a practical mandatory access control system based on a partially ordered, non-hierarchical labelling system and an access mapping from correspondingly labelled execution domains.


In security-conscious applications, such as the ones we study, security audits are routine and use of lint tools can enforce simple discipline.

notice that running example code is careful to restrict the browser context in which data is allowed to be embedded.


That is, a view may potentially be a single number.

a view is the essence of a system state.


The proposed method offers transparency by identifying if the user that is answering (or placing) a call is the authorized one.

we investigate if a user can be authenticated just by using the movement she performs, from the moment she presses start (to initiate a call), until she takes the phone to the ear.


In particular, we assume here that the attacker can manipulate samples corresponding to the digit 3 in order to have them clustered together with the cluster corresponding to the digit 6 , while preserving the initial clusters.

the desired clustering output for the attacker consists of three clusters: one corresponding to the 0 digit, one corresponding to the 1 digit, and the latter corresponding to the digits 6 and 3 .


The reliable isolation of all the comprising OS is necessary to ful.ll the requirements of the automotive environment.

the technique to establish a proper computing environment for multiple independent operating systems comes into focus regarding security considerations.


Let the root vertex of the hash tree be r. Then, for each node i, assuming that node i itself has never divulged the value of MACKi(M||N) in the past, exhibiting the value r suf.ces as proof of the ability to independently compute MACKi(M||N) since r was computed via a sequence of collision-resistant hash functions evaluated with MACKi(M||N) as an input.

it is computationally infeasible for an adversary that does not know Ki or MACKi(M||N) to produce a new pair M. ,r ,N. in such a way that MACKi(M||N) is a leaf vertex in some hash tree with root r .


Complementing research results in Gov-IS, risk management is an important issue in software projects highly documented in literature.

most research results refer to the early identification and management of risks as essential tasks for the success of a project [3, 9, 22, 15] - e.g.


If cheating is the economically rational choice, traditional access control systems base their security in a belief (hope) of the users benevolence.

most access control systems base their security on a belief that the subjects are benevolently irrational, while we assume they are maliciously rational.


The key idea here is to build DL predicates over enriched security metadata and a knowledgebase that semantically encodes the state of the world as observed by the decision maker.

we have used security metadata developed in [23] and an extended version of KANI ontology (Knowledge Associates for Novel Intelligence [9]) for building the knowledgebase.


The authors argue that location inaccuracy (lack of correspondence between information and reality), imprecision (lack of speci.city of information), and vagueness (existence of boundary cases in information) provide an feasible way for implementing location privacy.

they argue that their model provides a generic mechanism for balancing quality of information with privacy.


In this paper, we propose a single-packet traceback solution that is extended from the hash-based traceback scheme [19] but not relying on these assumptions.

our solution is fully distributed and resilient in the face of arbitrary number of collaborative adversaries.


RELATED WORK Our work in this paper is closely related to the recent results in intrusion alert correlation.

our attack strategy model can be considered as an extension to [9] and [29].


PERFORMANCE EVALUATION 5.1 Towards ideal implementation: a sample setup In the ideal case, an escort box is comprised of .ve components materialized in an as compact as possible blackbox: (1) a lowcost processor for protocol enforcement; (2) a large-enough but bounded memory used by the processor; (3) a wireless interface to connect to the LAN; (4) a wireless/wired interface to connect to the guest; and (5) a tamper-resistant shell to protect any physical tampering of the above four components.

we recommend to select read-only memory that can only be modi.ed/written after opening the tamper-resistant shell, so that mobile guests or other unauthorized parties cannot easily mishandle the escort box, for example, they should not be able to make the escort box run mobile agents or codes not conforming to pre-installed network protocols.


Initialisation When GA starts, one solution is created in increasing order, and the rest 99 solutions are created at random.


Our stack-structured approach makes it easy to incorporate permissions for dynamically allocated memory.

a function may allocate memory (using, say, malloc)and set permissions on it before passing the pointer to untrusted code.


In animal world, information warfare may occur whenever one party has, or contend to have, access to information that their opponents are keen to know (Krebs and Dawkins 1984, Kilner and Hinde 2008).

the asymmetry in physical prowess may motivate the physically weak but knowledgeable rivals to exploit information and get the upper hand (Kilner and Hinde 2008).


One idea is to use the Levenshtein (string-edit) distance between pronunciations, which is de.ned as the minimum number of phoneme insertions, deletions, and substitutions required to turn one pronunciation into another [52].

the string-edit distance has been shown to in.uence perceived word similarity in psycholinguistic experiments [10, 41, 58] and in real-world confusions [50].


(6)), a task, and a positive (+) or negative (-) decision value depending on if user u is consultant of customer c and is allowed to execute task s for this customer.

iAuth is granted by a function depending whether a user possesses a role that is linked to the user.


In the Extract phase our system processes the TVD policies and parses the individual XML .elds.

it extracts the systems the user selected, and includes resources associated with the selected systems.


Here we relax this obfuscation notion and only require that the proxy learn nothing about the encrypted messages (but the proxy might learn other things not exposed by black-box access.)

our notion of security allows for a deterministic re-encryption procedure, whereas the obfuscation notion of [21] mandates that the re-encryption process be randomized.


Approximations of the true information .ow are good enough so long as they capture the most important aspects of the information .ow.

as long as the output tells the user of the DIFT system something meaningful about the true information .ow in the system, perfect accuracyfrom an information-theoretic perspective, which is impossible to achieve in practice, is not a requirement.


FreeBSD, unlike most modern operating systems, implements cache coloring [12], which attempts to allocate virtual memory so that virtual pages correspond to physical pages.

cache coloring allows processes to predict which pages will con.ict in the cache, and optimize their memory accesses accordingly.


The protection object like representation is recursively obtained starting from the end of the graph, i.e., the last box applied over the internal streams, till reaching the input streams.

each time the function encounters a box, say box, it veri.es whether it is applied over a single or over more than one streams (step 4).


3.4 Misf t Characters in Entity Representationbreaking CSS Strings Combining aforementioned exploit with enabling CSS-escape decoding behavior results in yet another interesting e.ect observable in several browsers.

when both CSS escape and the canonical representation for the double-quote character inside a CSS string are used, the render engine converts them into a single quote, regardless of those two characters seeming unrelated.


It is important for the encryption scheme to be veri.able to prevent the SM from corrupting the decrypted aggregate result.

given the publickey PK and a ciphertext E(a), when given a and some randomness r, the server can verify that E(a)was indeed an encryption of a using r, and there is no bsuch that E(a)could have been an encryption of bfor some randomness.


In this paper, we look at this issue of data con.dentiality in the context of programs that operate on sensitive data residing in memory.

we focus our efforts on programs that are written in C, a widely used systems programming language.


In this paper we consider a threshold criterion.

if a bad node s compliance degree denoted by Xb with aprobabilitydistribution obtainedbyEquation1 above is higher than a system minimum compliance threshold CT then there is a false negative.


However, large amount of personal information is also exposed to public, not always with the consent of the information owner.

we believe there are three primary channels for personal information disclosure: Personal information on the general web.


Because this example has dependent but homogeneous components, the two conditional time-to-compromise functions are not identical.

the time-to-compromise of one component does depend on when the other component was compromised and the compromise times are expected to be very close to each other.


Nevertheless, it is important to stress that the noise and interference power is only an estimate that is generated by the vendors hardware.

it only represents an approximation of the current noise and interference power as it is determined from the current receiver sensitivity (which can be adapted within a certain range) as well as from channel measurements during idle times.


(2) The second extension is to dynamically generate model-related events from the detected internal VM actions at the VMM level.

our current prototype continuously monitors those kernellevel memory-writing instructions and checks whether they are attempting to modify protected kernel objects.


For example, a subject who participates in a collaborative project cannot write the data of the project to any .le or container that is readable by a subject outside of the project.

once the subject joins a project, it cannot access the object of another project that con.icts with the one it joins.


This might be more restrictive than necessary.

we would like to ensure that whenever an application accesses a previouslyunseen folder in a container, this should be allowed.


Since virtual machines are oftenusedby researcherstostudymalwareina containedenvironment, we assume that these bots in reality correspond to researchers studying theTorpig malware.

we were able to determine the nid values generated on a standard con.guration of the VMware and QEMU virtual machines and we found 40 hosts using these values.


This includes not only memory, disk, and all application software, but even the CPU, the BIOS, and the OS kernel.

note that the software implementing the virtual monotonic counter mechanism itself is considered as open to being attacked and controlled by the adversary.


Lastly, we also write the shorthand ., u, v |= f to mean ., n, u, v |= f. (Recall that n = |.| - 1.)

we begin traversal at the most recent time point.


If the attacker succeeds, then the BeamAuth token is compromised, and the attacker might then succeed at obtaining Alice s password through normal phishing means.

if an attacker can compromise both Alice s web and email channels, he can successfully defeat BeamAuth.


Our protocols achieve weaker goals: Our protocols output a graph AG that is not strictly isomorphic to G, but rather is isomorphic to a perturbed version of G. The perturbations consist of the addition and/or deletion of a small number of edges and/or nodes.

our protocols allow the adversary to learn some information about the isomorphism that maps G to AG, but ensure that the adversary learns only minimal information about the isomorphism restricted to honest  nodes in G. our protocols leak much less information about honest nodes than the simple approach based on pseudonyms described in the introduction.


The average latency aggregating the different categories is 50.2ms for the baseline, compared to 64.9ms with A3 protection.

the default non-optimized A3 CZs introduce a 29% overhead under this specific load.


We use I R to denote all the possible inference rules, which not only includes rules explicitly de.ned but also those that can be derived from others.

i R is the closure of inference rules under logical inferences [1, 3].


Although SNR is a simple way to measure the noise introduced by the embedded mark and can give a general idea of imperceptibility, it does not take into account the speci.c characteristics of the HAS and, thus, better measures should be used in the future research.

the use of HAS models should be investigated [17] or auditive perceptual tests might be performed.


Figure 4 illustrates that the protection area for guest Ais the entire circle.

the entire forwarding path between guest Aand its servers needs to be protected, especially at the bootstrapping time when ID is authenticated and access is granted.


Running code at system management mode privilege opens a number of challenges that need to be properly addressed to achieve the goals mentioned at the beginning of this section.

we must (i) trigger system management interrupts to switch to SMM, (ii)beabletoaccess all the physical [md5 (pkt) | pkt] (3)  C = md5(mem) (1) (4) sign(C)  (2) [0x00... -0xff...]  Figure 1: Overview of the system memory of the target system, even when more than 4GB of physical memory is installed on 32-bit hosts, (iii) guarantee the integrity of the collected data on the host as well as while in transit to a generic but trusted device.


Moreover Game qR is completely independent of the challenger bit b.

all next-ror queries return a ran $ dom R .


The users that assigned to a delegatable role are exactly the same as that assigned to a regular role it based on.

a pair of (regular role, delegatable role) will be used as a single role in user-role assignment.


Thus, pk is the expected evaluation of probability assignments in each rate zone j when rj = rk.

we can achieve the maximal unlinkability between communication pairs when all nodes transmit at the rate r1, and the minimal unlinkability when all nodes transmit at the rate rs.


2C that describes how each basic block shared with the victim (i.e., in the shared executable) is stored in one or more chunks mapped into the adversary instance s virtual memory.

here, C is the set of all chunks mapped into the adversary s virtual memory and occupied by the shared executable, and 2C denotes the power set of C. each basic block in B is mapped to one or more chunks, by BBToChunks.


Unlike most convertible undeniable signatures, multisigna- tures are compatible with the underlying (single-signer) sig- nature scheme.

the algorithm for verifying the mul- tisignature is identical to the algorithm for verifying the un- derlying signature scheme.


However, for safety, the goal is to be as complete as possible better safe than sorry so it is acceptable to have a false positive (i.e., an image occurrence that does not correspond to a real occurrence) but not a false negative (i.e., a real occurrence which is not signaled).

we need to report an alert for every image occurrence of s in lo and these alerts should be interpreted as possibly corresponding to real attacks.


On the other hand, improving the robustness of the feature set against evasion is very useful when facing code injection.

features that involve all layers described in Section 5, namely, STO, SUO and CE, should be extracted.


correctly observed, Non-control-data attacks are realistic threats [38].

malicious attacks on plain variables can yield signi.cant security problems, including unauthorized access and privilege escalation.


First, we argue that the algorithm used by AutoBatch to produce a batch veri.cation equation unconditionally satis.es Security De.nition 2.2.

the batch veri.cation equation will hold if and only if each of the individual signatures would have passed the individual veri.cation test (up to a negligible error probability).7 1.


The parameter space of .ash worms is much larger than that one scenario.

the size of the worm constrains how quickly it can be distributed, and there are tradeoffs in the tree design.


Therefore, if one knows the location of one particular library in a process, the location of every other library is 100% predictable.

if the libraries are moved as one cohesive block with static o.sets from one another, they can be regarded as a single component when evaluating the unpredictability of a movement.


There exists a peer-to-peer relationship between the CA s (roots).

it is a combination of many hierarchies.


An important observation is that the entire client-side code base does not have to be included in the replica.

display code does not need to be executed on the server because the replica is essentially headless there is no user to see the GUI.To further reduce the amountof code the replica must run, we can use a slicing analysis [51] to only include a portion of the client-side code that contribute to values included into RPCs.


Thus, attackers would need to .nd completely new attack classes.

we note that JSAND is capable of detecting previously-unseen attacks, when these attacks manifest in anomalous features.


Further, since an attribute in VOMS only includes role and group information in a VO, some policies cannot be implemented, such as user-level and VO-level delegation, and context-based authorization.

a user only can gain permissions from a VO administrator.


Although this is a breach of strict con.dentiality, our design goal was to provide pseudonymity, rather than pure anonymity.

without the ability to pair a user with the User device, the attacker cannot discover the identity through the request alone.


This well-known rule of inference can nicely specify the interleaving of retrieval and authorization in certi.cate chain discovery.

if A describes the condition of credential retrieval, and B describes the condition of successful authorization, then A .


We consider the problem of devising a fully distributed, non-interactive, robust, and adaptively secure construction which is as e.cient as the centralized schemes obtained from [55, 19] and does not rely on erasures.

we want to retain private-key shares of O(1) size, no matter how many players are involved in the protocol.


In this scenario, John should be allowed to .lter what videos his daughter is able to see.

we have a prohibition ( John , Jane , Video, PAll).


It veri.es that all hashes in the certi.cate chain are on the remote server s list of authorized software.

the remote server trusts the BIOS, the bootloader, and the TVMM.


For example, if we .nd a Sadmind Ping followed by a bu.er over.ow attack against the corresponding Sadmind service, we can correlate them to be parts of the same series of attacks.

we model the knowledge (or state) of attackers in terms of individual attacks, and correlate alerts if they indicate the progress of attacks.


Using the four-sample method, an attacker who does not know the distributions can attain an accuracy of 95.7%.

the attacker can effectively test for the existence of a .le in a shared second-level cache.


It e.ectively prevents replay attacks at the .le level.

an attacker cannot restore a .le once it has been deleted from the virtual private .le system, because its master entry containing the hash sum (and also the unique .le number) does no longer exist.


Based on the assumptions 1 -3, using sophisticated wireless signal detection devices (multiple detection devices might be deployed), adversaries can detect the wireless signal transmission power and transmission directions at any given location within a communication system.

the adversaries can locate the signal source.


In this case Bob is not to blame, since Bob can decide to ful.ll his obligation at time 14 for example.

st may possibly transit into a future state where a subject cannot ful.ll its obligation, which however is not due to any sub ject s negligence.


For a client (or attacker) to solve the puzzle requires bruteforce testing of all of the seed values.

for a ' given candidate value a, the client tests whether gc,t = f'(a') g .


TWITTER GEOGRAPHIC PROFILER This tool builds a map of the ethno-cultural communities of a person's friends.

we want to determine the distribution over the set of possible ethno-cultural groups of the friends of a given individual.


Note that JSand provides a one-way isolation and hence makes no attempt to protect a sandboxed script from its environment.

code running in the global security context, such as browser plugins and unsandboxed scripts, have the power to modify a sandbox s security policy or to inject a DOM proxy that allows access to any DOM object.


Because wireless communication is not secure, we assume an adversary can eavesdrop on all tra.c, inject packets or replay older messages.We assume that if a node is compromised, all the information it holds will also be compromised.However, we assume the base station will not be compromised.

2.2 Design Goals ThemaingoalofLEAPistodesigne.cient security mechanisms for supporting various communication models in sensor networks.The security requirements not only include authentication and con.dentiality but also robustness and survivability.the sensor network should be robustagainst varioussecurityattacks, andifanattack succeeds, its impact should be minimized.For example, the compromise of a single node should not break the security of theentirenetwork.


should not be exposed in order to comply with the security in CK-framework (unless sB is not speci.ed to be part of the session-state).

if sB is speci.ed as part of the session-state, the provable security of HMQV will become much limited.


The rule for the I-hierarchy, (x=iy), implies that if (x=iy) holds, then the permissions that can be acquired through role x include all the permissions that can be acquired through role y.

permissions of the junior roles are inherited by the senior role.


A limitation of this method is that the attack strategies extracted from intrusion alerts heavily depend on the underlying IDSs and alert correlation system.

if the IDSs miss a critical attack, or the alert correlation system leaves a critical step out of the corresponding attack scenario, the attack strategy may be split into multiple ones.


However, if Eve is active (i.e., can modify the messages), the problem becomes considerably harder.

one needs to worry not only about achieving R that is 2-.-close to uniform, but also about ensuring that Alice and Bob output the same R with probability at least 1 - 2-. .


We show that it is feasible to implement a secure NFC-enabled and smartphone-based immobilizer system.

we discuss the conditions for the secure integration of enhanced features such as delegation under a strong but realistic adversary model, where the adversary has full control over the software on the smartphone platform.


Speci.c problems concerning the application of fuzzy inference to access control are investigated and solved.

the correctness of the solutions given in this paper are provable.


we later show that Mallory can be successful with very high probability even when k<< l.It turns out that Mallory has high probability of being successful even when she does not know the identity of any of the queries in Q.  Mallory has an m × m matrix M.Each (i, j)th cell  in matrix M contains the expected probability of both ith and jth keywords appearing in any random document d .D.Mi,j = Pr [(Ki .


Of course, we cannot expect to detect all possible types of malicious activity.

our detection approach will fail to identify malware programs that ignore other applications and the OS (e.g., the malware does not attempt to hide its presence or to gain control of the OS) and that carry out malicious operations only over the network.


We provide the .rst proof that SSH is ACCE-secure.

we show that the signedDi.e Hellman ciphersuites in SSH are ACCE-secure, under reasonable assumptions on the cryptographic primitives used.


In uPro, isolation between threads is provided by protection domains.

protection domains are realized through Software-based Fault Isolation (SFI), which allows isolation in the same address space.


A variable assignment de.nes the values of some entity variables.

each variable is bound to a single entity in the relational structure.


Therefore, we conclude that snapshot-based integrity monitors are simply not apt for detection of transient attacks.

an event-triggered solution is essential to cope with transient kernel attacks.


The only choice for the user to not provide such data is to not use the application.

tPA providers access the contact list of the TPA users and fetch information about the friends of the users, even though those friends did not install the application themselves or consent to this access.


Forbidden views and disclosure limitations are instead modeled as hard clauses, since they cannot be violated by any truth assignment.

we de.ne a clause for each forbidden view and a clause for each disclosure limitation, as follows.


Unfortunately, the peak of the initial curve occurs at about the same time that the passive monitor data became un- available, so the duration of the 2,000 host/minute infec- tion rate is unknown.

the large spike corre- sponds to 7,700 hosts; it is an anomaly caused by a small gap in the collected netflow data that resulted in detection of all hosts infected during the down time when collection resumed.


3. removeAllRoutes(VM_instance) removes all the .ow entries associated with that VM_instance.

removes all .ows installed for createTraf.cRoute API calls which is associated with VM_instance.


However, these techniques may not be exhaustive nor sucient to thwart all security attacks.

each of these devices and their interconnects must be trustworthy; otherwise, an attacker can simply tamper with the information they provide to the coordinator and pump.


In this paper, we investigate the feasibility of eavesdropping the PIN-Vibra vibrational channel.

we demonstrate how the acoustic emanations associated with a vibrating mobile phone can be eavesdropped upon from a short distance.


Since there are 4 di.erent acls (i.e., {A, B}, {A, B, C}, {B, C, D}, {A, B, C, D}), and 4 users we de.ne 8 di.erent keys, one for each acl and one for each user.

keys ka,..., kd are associated with users A, .


Quite similar to what happened in the .eld of program veri.cation, where speci.c properties (e.g., partial correctness and mutual exclusion) were investigated before the introduction of the unifying safety-liveness framework [12], the same kind of development was made in the .eld of cryptographic protocols.

speci.c cryptographic security properties were investigated before the introduction of the unifying notion called universal composability [2], or its equivalent (but perhaps more intuitive) version called concurrent general composition (arbitrarily many instances run possibly together with arbitrary other protocols) [13].


The computation is actually simple, since for each term the coefficient of si is determined when x=0.

we can pre-compute those coefficients as constants, so that polynomial interpolation only needs k multiplications and k-1 plus operations.


The maximal potion of time the system can afford to stay in con.guration C1 is * µN -d p1 = , (5) µN -µ1 while the system will stay in con.gurations C2,...,CN respectively with portions of time given by ** * d-µ1 p2 = ··· = pN-1 =0,pN = .

µN -µ1 MTD is (µ1,··· ,µN ,p1 * )-powerful.


As discussed, we group multiple targets to a single victim if they point to the same web server.

we group attack targets that point to equal IP addresses, resulting in 646 victims.


To prevent this, the IDS needs to create the testing packets such that they resemble packets which are part of the normal traf.c of the network.

the payload of the testing packets should have the same pattern as the normal traf.c of the network does.


We used the expert classi.cation for little datasets, but it was impossible to apply to huge volumes of payloads; so we resorted to both manual inspection and proof of concept tasks to evaluate the correctness of the classi.cation.

in Figure 2 we present the results of the training of a 10 × 10 Self Organizing Map that creates a division of the data in 100 clusters.


[o f1] 3)]) (get o f2)) We may .nd during analysis at this site that the abstract value of variable f1 is {foo, bar}.

we may be setting either the key foo or the key bar.


the simulator will know the randomness that produces them), but they are unlikely to be chosen by an honest run of the update algorithm.

they are valid updates, but are chosen from more restrictive distribution.


In addition, the degree of trust in a credential for verifying certain attributes of its possessor also depends on the trustworthiness of the party issuing the credential.

in a distributed environment with no central certification authorities, all credential issuers may not be trusted to the same extent [3, 5, 4, 6] and consequently, the assertions made in the issued credentials may fail to certify the claimed attributes of the user with the desired degree of trust.


For brevity, in this work we consider the SA, who can potentially realize a consistent number of threats with respect to the others insiders.

thanks to its privileges, he could install malicious software/code, create backdoors, disable system logs and anti-virus, create new users or change users privileges, install remote network tools, plant logic bombs [16], perform operation on data base in order to have Secure!


We also conducted a separate analysis targeted at the blue i mark which indicates that basic information is requested by the app (see Figure 7).

we were wondering whether there is a distinct effect on the publishing check box to the right of the blue mark (circled in red in Figure 7).


It is not clear today whether the knowledge of 200 bits scattered over 512-bit exponent is su.cient to break RSA.

we do not know any methods that can directly leverage this information to factorize the public modulus.


Unfortunately, we show that doing so is not su.cient.

since the SSH speci.cation does not require the padding to be random, the resulting SSH implementation may be vulnerable to a rather serious reaction-attack (a privacy attack that works by modifying a sender s ciphertexts and observing the receiver s response).


It gives the reputation system an opportunity to observe user activities for an extensive period of time, thus has a better chance of recognizing previously unclassi.ed accounts, either good or bad.

we use the reputation score of July 2011, which provides us with an updated user reputation   Figure 7: The cumulative fractions of the percentage of accounts that registered in the top 1 month.


Firstly, soundness has been challenged due to their inability of handling certain types of active attacks.

protocols suffering from attacks utilizing multiple parallel executions have been declared safe using these methods.


This means that, e.g., a 60-bit .ngerprint extracted during this time frame would have only 5.8 bits of total surprisal on the average.

the attacker would have a 2-5.8 1.8% chance of guessing the exactly correct context .ngerprint by utilizing pro.ling information.


Another potential approach to the problem of unintentional killing is to constrain the power delivered to a tag by modifying the reader protocol.

we suspect that an abrupt cutting of a reader s emission in the course of a KILL command might put a tag reliably in the low-power regime.


For each candidate 6-character substring, only the last 5 characters are used for hashing, to determine the storage location of the 6-character substring.

for a given 6-character substring, the hash of the first 5 characters points to the hash bin location of the previous candidate substring with the last 5 characters matched.


(The underlying for these calculations can be found in the Set Cover Tracing Algorithm [3].)

although there are a lot of players that score 5, the chance that four of them combine to explain all twenty movies is relatively small.


All participants are university students with diverse backgrounds and did not join our previous studies.

25 participants (10 females and 15 males) are from the computer science department (not security related major) and the other participants are from other departments and majors.


In our case, a textured image is CAPTCHA text, and a scene is a 3D object as shown below: Figure 1.

projective CAPTCHA Image Texture Mapping the projective texture mapping involves the following: 1.


Given this model, our main security goal is to implement a virtual monotonic counter mechanism that is at least tamper-evident from the owner s point-of-view.

at worst, all the client devices of the owner of a virtual monotonic counter must always be able to detect any failure or erroneous behavior of the counter caused by an attack by the host or another owner.


3.2 Registers In alphanumeric shellcode, not all instructions that take registers as operands can use any register for any operand.

none of the data-processing instructions can take registers r0 to r2 and r8 to r15 as the destination register Rd.


We create an N2 (= m 2 n 2)node graph G whose vertices correspond to all possible rectangles of the grid.

each vertex v in G is associated with a rectangle R(v)whose bottom-left corner is (a(v), c(v)) and whose top-right corner is (b(v), d(v)).


Problem 2 (Tag Transmission): How can primary users transmit authentication tags, so the tags can be retrieved by CR receivers from the signal at the physical layer, while the tags do not interfere with non-CR receivers functionalities.

authentication tags should be transparent to non-CR receivers.


We portedWeirdX to enforce authorization policies using TMI.

we used TMI in conjunction with the XACML framework to formulate and enforce several policies that have been discussed in priorwork[40], including preventinga rogueXclient from killing arbitraryXclients, and mediating copy/paste operations.Forexample, we enforced the Bell-LaPadula policyon howdata copied from anXclient can be pasted to otherXclients.1 Overall, our port of WeirdX required about 4,800 changes in 25 classes, and introduced 108 transactions to the code that dispatchesXprotocol requests to handlers; as with FreeCS, most of these changes were related to replacing reads/writes of transactional objects with DSTM2 accessor functions.Wealsohadtomakeafew changestoWeirdXcodethat handled outputtothe screen.we modi.edWeirdXto bu.er writes that happen within transactions, and .ush thebu.ers only upon a transaction commit.


The indirect trust that mesh router i has in a neighbor mesh router j is obtained as a function of the direct trust that everymesh router k has in j.

we represent the indirect trust provided by node k to node i as an(n-2) -.


For any frontiers F and G, de.ne Pr[F = G | x, y, Ch] = Pr[u | x, y, Ch] {u.F |u is a pre.x of some u1.G} the weighted probability of all the transcripts in F that are pre.xes of transcripts in G. In the same manner de.ne Pr[F < G | x, y, Ch] for transcripts which are strict pre.xes.

3no string in F is a proper pre.x of another string in F .