Enhanced approach using trust based decision making for secured wireless streaming video sensor networks

The advances in the expanse of image sensors have made it conceivable to make high-resolution picture sensors easily accessible. The amelioration of wireless interactive media sensor networks are found to be greatly increased due to the day to day usage of cameras, microphones and smart devices. A secured multi-hop routing mechanism is addressed in surveillance areas which could be incorporated to the multimedia sensors that are capable of peruse the detected data comprises of recorded images and videos. Also, malevolent sensor hubs could be interjected into the vigilance area in an untrusted environment. In this contemplated venture, a novel lightweight trust decision-making framework is accomplished for QoS clustering to give secure routing in both intercluster and intracluster communication. A quantifiable aberrant trust value is the variable determined by the Cluster Head (CH) for its Cluster Member (CM) inside the cluster. The LEACH (Low Energy Adaptive Clustering Hierarchy) protocol is adopted for group formation and also for the exchange of the trust values among the master nodes, member nodes and Base station. In this way, the correspondence overhead, likelihood of dynamic assaults for example sinkhole and black hole assaults mount by eavesdroppers can be reduced by maintenance of trust values by cluster heads rather than cluster members. Besides, in wireless streaming video sensor networks this approach authorizes us to predict and counteract malicious untrusted and flawed nodes. Simulation results using NS-2 is examined and the suggested trust decision-making model escalates the dependability, elasticity and low memory aloft in comparison with the current trust models adopted for wireless video sensor network security.


Introduction
In the digital world, wireless multimedia sensor networks (WMSNs) are mainly facilitated by the modest, cheaper and novel technologies in radio communication, media transfer and digital standards. In smart agriculture and industrial applications sensor motes are meant for measuring temperature, humidity and other physical properties, Likewise, for capturing and processing video and audio sensory information WMSN interconnects self-governing devices from various extremities [1] to the surveillance station. WSNs are flattering cost effective, power consuming, versatile, and feasible [2] expected because of the elevation in usage of microelectro-mechanical systems (MEMS). Most of the researchers in video sensor networks focusing on minimizing power consumption and maximizing the transmission power [3] but the real value is data reliability. Typically the primary origin of vitality in a sensor mote is a battery; so the life time for any hub relies upon the life of the battery itself. Therefore numerous Media Access Control (MAC) conventions have been proposed to expedite data transfer by enabling an disabling occasionally instead of keeping the channel in ON status for the entire duration e.g. SMAC [4]. Information transmission in ecological, security, and wellbeing observing requires Quality of Service (QoS) combining with Quality of Equipment (QoE) apprehensive system in addition to a specific end goal to guarantee productive use of the assets and viable access. Envisioning precise real time image data can be carried out by deploying larger scale, video enabled wireless surveillance networks in the aforethought regions. In this kind of context, a few complex mission programs frequently require cryptographic mechanisms with the intention to gain protection in addition with QoS and QoE. For example, Wireless Video Sensor Networks (WVSNs) adopted in maximum of the defense applications require an excessive stage of security. Hence, it is crucial to build with ease conversation mechanisms between nodes of the community [5]. Authentication, Confidentiality and Integrity can be accomplished by Cryptographic primitives. Conversely, to combat attacks such as tampering of messages, packet dropping and Denial of Service (DOS) attacks, a secured mechanism that provides a completely trusted system is greatly addressed [6].
Customary trust administration blueprints that have been produced for wired and radio transmission systems could not be applied for interactive media sensor systems on account of higher utilization of assets, for example, memory and power assets [7]. In maintaining the QoS and QoE the power consumption is highly focused in clustering by adopting various clustering protocols. Trust Based LEACH is proposed in this paper aims at to assign power consumption at every node in the video sensor networks uniformly. Data gathering and restricted harmonization between nodes is supported by LEACH so as to minimize the resource consumption among the nodes [8]. The trust values are manipulated between the nodes using simple mathematical calculations which requires minimum computation time and less memory overhead [9]. However the trust decision making system requires the nodes to calculate the trust values during the network creation itself so that the possibility of the intrusion of untrusted nodes are considerably reduced. If the nodes performs the necessary actions of the specific networking rules the trust values are increased. Presumption of a trusted domain which may not be reasonable for each applications [10] as suggested by conventional research work in video sensor systems.
The suggested work depends on the trust values to ensure the security of the video sensor networks. The absolute aspiration of the venture is to provide the secure correspondence over a radio enabled video sensor networks by outlining a lightweight and reliable trust framework for WSNs against various attacks injected Eavesdroppers from various locations. Furthermore the proposed framework builds up a trust-based structure for clustered WVSNs, as well as the component that decreases the probability of malevolent motes being chosen (or chose) as synergetic and authorized nodes. The light weight trust management system is implemented in NS-2 simulation tool for clustering and secure routing in the network with eavesdropper nodes. Performance evaluation results shows that the proposed system shows the elevation in Packet Successful Delivery Ratio and contraction in Loss of Aggregated data, energy consumption, resilience, end to end delay when compared with existing Group-Based Trust Management Scheme for wireless sensor networks (GTMS) [11].

Literature retrospect
In order to enhance the secure and dependable trust system for the WVSNs, the review enforces to surf the related works and selected papers are discussed in this section to gain the related information for the implementation of trusted sensor network. Several suggested combat methods relies on the random key pre-distribution techniques [12][13][14]. To resolve this issue In [15], the researchers formulated the one way hash function to hash the keys for each periodic rounds According to this approach using the one-way hash function all the keys are hashed. Once the participating node in the WVSN accepts the key it will be hashed. Hence for each rounds the newly hashed keys will be chosen by the nodes for ensuring the security.
But the aforesaid mechanisms consumes energy and memory so that to preserve the predefined activities of wireless video sensor networks. In military surveillance areas the video and image files consumes more amount of memory and battery life which will affect the QoS and QoE in the intended networks. In addition with the QoS steering algorithms [16,17], QoS MAC procedures [18], and cross-layer QoS solutions [19] numerous mechanisms are proposed to address the QoS maintenance in contrasting layers of the network stack.
By examining above issues Rui Dai et.al [20,33] designed a load balancing mechanism using correlation aware differential coding scheme to minimize the network congestion often occurred in the media network. This work fully focuses on the even distribution of energy consumption throughout the network. As the visual information can examine the sight only inward the field, the FoV (Field of View) depends on the four factors the location (P), the sensing radius (R), the sensing direction (V), and the offset angle (α).focal length is depends on the projection (2D or 3D). By calculating the focal length of the distributed camera networks the interrelationship between two cameras are calculated by rend these flows into various paths inured to reduce the network traffic. The proposed QoS routing algorithm attains efficient conveyance of ocular data. However the calculation of the focal length remains time consuming in the large scale networks with high priority traffic where the visual data needs to be reached soon.
Focusing on low latency to real-time traffic, An Adaptive MAC Protocol with QoS support (AMPQ) for heterogeneous wireless sensor networks is suggested by Marion Souil [21]. In his work high channel usability is achieved by hybrid nature of the video sensor networks by enabling and disabling the assertion in the MAC layer. In radio based video sensor networks the couple of traffics are mostly involved such as backdrop traffic and multimedia abundance. These are often occurred by the external factors such as climate and gleaming. According to his study the main intention is to prioritized ocular and streaming data with high priority and data with less preference. According to the probability values the latency and throughput is distributed. Thus this protocol facilitates the QoS standards and furnish the adaptability and robustness of the multimedia networks. Besides keeping the flexibility of the network, several other factors are not meet in the system such as transfer rate, flawless allotment of resources and bandwidth restrictions.
To overcome the issues in AMPQ, Arar et al. [22] proposed a method of targeting information sharing amidst all layers in the cluster based WVSN so as to make the network more adaptive. Cross layer framework is investigated to optimize the resources in addition to the ocular & streaming distortion and packet mislaying during the allotment of resources among multiple interactive media sensors. A proximal minimization algorithm is proposed in the study f1or achieving the optimal distribution of energy, bandwidth and correspondence rate for achieving QoS. This framework is extended for motes combining multiple sources for battery power by harvesting energy to a maximum extent by targeting the balance between sustainable and grid sources. This method greatly helps in distributing the energy in the clustered sensor networks by adopting accurate cluster head election schemes. The (AMO) Animal Migration Optimization algorithm is proposed by X. Li et.al [23] as an advancement of cross layer clustered networks. This framework mainly targets on the clustering formation and successor mote recognition.
In cross-layer designs, the protection based surveillance networks get facilitated by appropriate security mechanisms by providing high encoding power as the proposed system provides optimal energy and processing capability. Nonetheless the interruption of the malevolent nodes is highly vulnerable and makes the network to be fatal. In addition with the optimal resource allocation and maintenance of QoS requirements, protecting the sensitive data from the trusted sources is more important. To address the security issues many QoS enabled security mechanisms are proposed by researchers. In reputation-based framework [24], for sensor networks a Bayesian formulation using beta reputation system is preferred to evaluate their trustworthiness in which each node preserve the status for other nodes. Since the network employs cryptographic primitives but it alone cannot prevent malicious attachment of data from internal rivals or predatory nodes. By considering the above flaws, In QoS clustered networks, distributed trust assessment strategy is designed with the progressive structure for proficient data exchange [25,38] by comparing the trust values. This strategy provides consistent updating of objective trust and subjective trust in addition with maintenance of application layer security. More difficult issue is that the sensor motes might be tampered and perform pernicious assaults, for example, data dropping or information alterations to disturb ordinary activities of a WSN wherein SNs probably perform unattended tasks. Researchers have actualized a trust enabled steering scheme for dynamic WVSNs [26] to secure the WVSNs against attackers misleading the multi-hop data transfer. According to this system the two parameters such as t-instrument and r-certificate is maintained for individual node trust and dependability. In addition to that, for ensuring the trust and trustworthiness of its hosting node all participating nodes in the surveillance networks should be locally hold a mobile agent. By this way, mobile agents provide both inter and intra trust values. In some circumstances the mobile agent can be an eavesdropper node and there might be a chance of injecting the devastating attacks. To combat the above issues, a group based trust management scheme is proposed in which the group trust value is calculated at regular time intervals for ensuring trustworthiness during authentication, authorization, or key management [11]. All the participating nodes in the networks can ensure whether it enters into the trusted zone or cluster. By this way a resilient video sensor networks is built with group trust calculation.

Trust based decision making for secured wireless streaming video sensor networks
The proposed secure trust administration is to advance the defended data transfer in the remote sensor systems against mischievous hubs. In surveillance areas the images and videos captured by the sensors equipped with IP cameras can be altered by the adversaries [27]. They usually inject the passive attacks and active attacks in the network to make the whole process compromised. Some of the passive attacks such as tampering, radio jamming and message modification can be detected and prevented by various security mechanisms [28]. Image sensor nodes can be spoofed in by the enemy and can falsify the information during the communication occurred via data link. Sensor nodes yet to be sustainable to these assaults. In this way, one of the real difficulties in such systems is the manner by which to offer secure association amongst sensors and the base station and how to transfer the information while keeping up the security prerequisites without altering the restricted assets. But the recent studies do not focus on the preventive mechanism for active attacks [29]. The combat mechanisms focuses only on the encoding and novel key generation techniques. The suggested Trust Management System (TMS) will reduce the probability of compromised or malevolent nodes being function as participating nodes. The outline of the working model of the proposed framework is depicted in Fig. 1.
In this work, eavesdroppers inject the active attacks such as black hole and sink hole attacks in different clusters to make the network compromised. They usually perform their behavior [34] without any agreement or mutual cooperation among them. Here E1 will inject the blackhole attack and E2 will inject sinkhole attack during the cluster communication. The proposed trust-based mechanism will combat these attacks and moreover avoid these malicious nodes in the participation of data transfer permanently.

Our contributions
Based on the insights, an efficient investigation of a trustworthy administration framework for the clustered WVSNs focusing both trustworthiness and asset efficiency for maintaining the QoS is designed. In addition with the resource allocation, the surveillance networks need the security level to the atmost degree for the efficient and reliable communication. Many video sensor applications are equipped with sensors such as agricultural assisting robot [30], industrial automation [31,36], and smart vehicles [32,35] where security is not prioritized as it is dealt with the sensor data [37,39]. But in the sensitive applications such as military surveillance areas, cyber agencies and banking sectors the ocular and streaming data is the primary source which need high protection. To address the above issues the trust based formwork is suggested for providing the security from the network creation itself. The following are the contributions of the proposed ideology:

Cluster creation
The scattered motes in the video sensor networks are organized into simple clusters using LEACH protocol. Here the sensor nodes equipped with cameras are partitioned into small clusters. Initially nodes with high battery power is chosen as Cluster Head (CH). The nodes other than cluster heads which can quickly respond to the request messages forward from master nodes can group into clusters. The rest of the other nodes can join into the adjacent clusters. The resource allocation is performed through change in the election of cluster heads with probability k. The proposed trust framework helps in the determination of trusted steering motes through which an individual CM can send the trust values to the CH. The accumulated information is then transmitted from the corresponding CHs to the focal BS through different CHs.

Launching active attacks
In the proposed system the trust reliability is tested with the eavesdropper attackers E1 and E2 which endeavors to expand the effect of making the trusted nodes into malicious in different clusters by trading off the motes in each objective area. Specifically, the assailant could acquire more access by trading off quite small number of image sensors in different groups, as opposed to making them malevolent that are conspiring with each other. These malicious sensors could see or tamper the image and video data on sensor communications, act like genuine motes, disrupt the operation of the sensors by forcing themselves as motes in-the-center, and upsetting administration in many ways. Both malicious nodes thoroughly monitoring the transmission of packets and the trust decision making interactions throughout the network, launches active attacks such as in the clustered sensor network.

Trust evaluation
The framework for trust administration remote systems is a procedure that can be utilized to keep the basic verdict building of the systems. It helps the video sensors from parent network (trustors) to manage susceptibility about the future activities of another participating nodes (trusters).
Initially all nodes in the participating network are allowed to exchange the HELLO packets during the network creation itself. During the data transmission mode the cluster head calculate the number of successful and unsuccessful interactions. The motes which reply within the predetermined time limit can be claim for successful transmissions. Those

Establishing trusted path
All the image sensors working on the basis of trust values maintained inside the cluster as well as inter-cluster. The malevolent nodes if tried to participating in the network it has to share its trust values which may be not possible as it possess LOW trust value when it made ambiguous and delayed transmissions. The malicious node turns it into an untrusted node due to the dropping of packets both in inter and intra cluster levels. The suggested trust decision making framework should avoid the data transmission in the LOW trust path (such as the path where the black hole node and sink hole resides). Consequently the trust based system won't enable the noxious nodes to take part in the correspondence over some undefined time frame. The malignant hubs are not able to betray different sensor motes as the trust choice depends on the two assessment delivered by CHs and Base Station. The trusted way is designed for the transfer of information in the WVSNs.

Network model
The topology is created for WVSNs with specific number of nodes in the simulation field. All sensor nodes within the cluster and intercluster simultaneously send HELLO packets to the adjacent nodes at a specific time of 1 s and a speed of 1Mbps.The cluster members calculate the number of successful and unsuccessful transmissions during the node creation stage itself. NS-2 Version 2.35 simulator is used for showing the experimental results. We have tested with around 50 nodes scattered in the field size of 1000 m * 750 m.The delay in transmission is calculated parallel and saved in the patch file. Two hacker nodes are designed with normal transmitting rate at the time of creation. For configuring the communication UDP and NULL agents are widely preferred. The threshold limit is set and the nodes are allowed for exchanging the packets for the predefined time taken as 60 s. All the video sensor networks are fully depends on the sink node for the data gathering and aggregation. At the initial level itself the sink node is set in the simulation field itself. (Fig. 2).

Batch formation using LEACH protocol
For ensuring the QoS parameters in the WVSNs the resources such as battery life, storage capability and bandwidth are equally distributed among all nodes both inter cluster and intra cluster by adopting LEACH protocol. It normally uses TDMA fashion for organising the clusters. The nodes with strong transmission power is elected as Master nodes. The neighbouring node which can reply to the REQUEST message sent by master nodes within the threshold time forming one cluster. The remaining nodes can join with the adjacent clusters within its communication range. Normally LEACH protocol comprises of formation phase and transmission phase. The master nodes are chosen in the setup phase. In this stage the node with strongest received signal strength is elected as CH. All the member nodes can accept the Bjoin Packet^with their corresponding IDs to form one cluster.
In the data transmission phase, the master node is determined and the node IDs and count of failed and reached transmissions is sent to the adjacent CHs and also to the BS. When data is transmitted between nodes the election of CHs is simultaneously done with some probability k. Considering that the masters and members are sorted out into clustered QoS enabled WVSN with the assistance of a group formation scheme. Let us consider the master nodes and the sink nodes are trustworthy and won't be attacked and altered. Each master gives two way correspondences. One with the member node and another with base station. BS give multihop communication mode from members and also among the master nodes. The sink nodes also get the trust values as the CHs and CMs.
In the proposed scenario, One CM sensor node send message to base station node through CH and eavesdropper nodes will listen to the packet data as intermediate nodes as assumed.

Fig. 2 Network Creation
Upon monitoring the transmissions, the attacker could easily discover the recorded images and streaming data. Susceptibility of monitoring and eavesdropping are also encountered in the Network traffic. Using NS-2 tool clusters are organized in the network area (Fig. 3) and given various colors (red,black,blue,purple,brown,cyan) for differentiation. The attackers in node 2 and node 11 are not colluding with each other and they may be in different clusters injecting active attacks.

Compromised network with active attacks by eavesdropping nodes
After cluster formation the nodes are exchanging their cluster IDs to the corresponding master nodes. In this instance the adversary node makes itself as the sink hole attacker which has the capability of dropping or halting the communication over the sink node. The central part of the network i.e. sinknode sometimes experience the state in which all the packets will be dropped by the node targeting the sink node. Typically the member nodes expends the appropriate data from all sources and draw in towards the sink hub. Once receiving the RREQ the noxious hub dependably sends RREP without performing standard AODV (Adhoc On demand Distance Vector routing) tasks by advertising itself with the highest Destination Sequence number. Since AODV considers RREP with the goal arrangement number to be new, the RREP sent by the malignant hub is also dealt with fresh route. In this way, malignant hubs prevail with success of infusing Sink Hole assault in the system as in Fig. 4.
In the same way adversary 2 launches blackhole attack by attracting the node by advertising itself with the fresh route to have the high sequence number. Once the route is established all the media data will get dropped or may be altered. In our simulation, as shown in Fig. 5 Node 11 is the adversary 2 poses the packet dropping attack.
By running Perl Script cat out.tr | analyze. Perl in terminal, it is evident due to the presence of active attackers the functionality of the system is degraded. This results can be analyzed

Preventing active attacks by trust based mechanism in WVSNs
The general trust computational model used to calculate trust values in WSN is shown in Fig. 6. The trust decision making is solely depends on the number of flawless and failure transmissions in the network. The trust should be maintained both intercluster and intracluster for efficient and secured data transfer. The dispositional risk is the external factors which induce the change in trust values. These can be occur due to external factors network traffic, power constraints and memory outage.

Algorithm for Trust Decision Making
Initial condition: Node advertise with other node in the clustered sensor network.

Member-member trust
The calculation of the trust at member level is defined by the following eq. 1 Δt window of time S x, y positive interactions U x, y failure interactions

Master-member trust
The master node will normally exchanges the REQ packets inside the cluster. All the member shares their trust equivalent within the cluster as well as to the master nodes. In matrix 2 all the trust values are maintained by the master node as shown below Compute the Ma-Me by the following proven mathematical formula 3 Where, R ch,y is the Ma-Me on y by the CH as in eq. 4 r implies count of positive transmissions, and v denotes amount of negative transmissions w.r.t master node .

Ma-Ma trust calculation
The trust evaluation approach at CMs is defined by the following eq. 5 where. T i,j is the Ma-Ma trust value of the channel heads. Compute the Base station to the master trust value of a Cluster Head j by the Base Station by the following proven mathematical formula 7 Where, F bs,j is the Bs-Ma trust. If the malicious node having higher trust value need to participate in the data transmission then the data packets are transmitted through the black hole node and sink hole, the malicious nodes drops the data packets. Over a period of time the trust values of the adversary nodes becomes less and at that instance no communication allowed via that path as shown in simulation result Fig. 7. After the trust computation all the nodes with the high trust values are allowed to participate in the network. Node 2 and Node 11 are no longer participating in the data transmission as it holds the negative trust values.
When we analyzing the network performance by running the perl script in the simulator it shows a good elevation due to the secure communication.

Performance evaluation
To analyze the overall performance the metrics such as Dependability, Packet Loss, Energy consumption, Resilience and End to End Delay are taken for comparing the efficiency of the proposed system with the existing trust based systems. Summarization of the comparison results between our proposed Trust Management System (TMS) and GTMS framework [11] is shown in Table 1 as both the systems has similar networking functions. These below values are  Table 1.The comparative results reveals that the proposed system shows the increase in performance metrics when analyze with the present security mechanisms.
In Fig. 8a TMS provides comparatively high PDR thereby improves the network performance. In Fig. 8b it is noted that the obtained Loss Percentage of proposed TMS is comparatively less than the existing GTMS.
From the analysis of Fig. 8c, the energy consumption in TMS is much lower than that of GTMS with LEACH Protocol at the same round of simulation. From Fig. 8d, it is obvious that with increase in compromised nodes, the Fraction of Compromised Communication (FCC) in TMS is much lower than that of GTMS. The graph Fig. 8e is plotted by taking number of packets transmitted in X axis with respect to time in Y axis. The End to End delay produced by TMS is comparatively less when compared to GTMS. Furthermore X graph is plotted using the various metrics values obtained during the transmission of the data. The X graph is generated for energy consumption (Fig. 9), resilience ( Fig. 10) and End to End delay (Fig. 11) for showing the analysis of the proposed system with the existing LDTS [9] technique.

Conclusion
In this paper, trust management system with enhanced approach is proposed for the effective communication between the nodes. Due to the change in roles of the nodes resource efficiency is at most maintained for preserving QoS and QoE parameters. The resource allocation is performed accordingly when there is change in masters and members. In protected areas for maintaining the sensitive information in addition with QoS and QoE a secure data transfer is needed. Focusing on the secure data transfer, a novel trust based communication platform is suggested for transferring the multimedia content more efficiently by combating the active attacks. Though the attackers posing the attacks at any instance, by applying the trust calculations the adversary can be avoided in the participation of the network. This proposed system is also light weight as it requires only simple mathematical calculations and consumes less number resources. Moreover the proposed system is tested with the adversary intrusion to check its efficiency by analyzing whether it chooses the alternative paths. Simulation results shows that the proposed trust establishment strategy proves to be more efficient than the current mechanisms.
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