Active measurements are integral to the operation and management of networks, and invaluable to supporting empirical network research. Unfortunately, it is often cost-prohibitive and logistically difficult to widely deploy measurement nodes, especially in the core. In this work, we consider the feasibility of tightly integrating measurement within the infrastructure by using Software Defined Networks (SDNs). We introduce "SDN as Active Measurement Infrastructure" (SAAMI) to enable measurements to originate from any location where SDN is deployed, removing the need for dedicated measurement nodes and increasing vantage point diversity. We implement ping and traceroute using SAAMI, as well as a proof-of-concept custom measurement protocol to demonstrate the power and ease of SAAMI's open framework. Via a large-scale measurement campaign using SDN switches as vantage points, we show that SAAMI is accurate, scalable, and extensible.
The notion of using network devices to perform active measurements was first standardized in @cite_27 and @cite_2 , protocols for performing one and two-way active measurements of delay and loss. Our work is broader, generalizes these protocols, and provides a means for such schemes to be implemented in network switches without explicit vendor support. Most closely related to our own work is SDN traceroute @cite_10 , a technique to reveal the sequence of switches and ports that actual data-plane packets traverse in an SDN network. SDN traceroute relies on injecting measurement probes via messages, and installing rules to match and retrieve tagged probe traffic via messages. While SDN traceroute and rely on the same primitives, is designed to provide a platform for existing measurements, IP-level ping and traceroute, using SDNs.
@cite_27 @cite_10 @cite_2
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Software-defined networking provides flexibility in designing networks by allowing distributed network state to be managed by logically centralized control programs. However, this flexibility brings added complexity, which requires new debugging tools that can provide insights into network behavior. We propose a tool, SDN traceroute, that can query the current path taken by any packet through an SDN-enabled network. The path is traced by using the actual forwarding mechanisms at each SDN-enabled device without changing the forwarding rules being measured. This enables administrators to discover the forwarding behavior for arbitrary Ethernet packets, as well as debug problems in both switch and controller logic. Our prototype implementation requires only a few high-priority rules per device, runs on commodity hardware using only the required features of the OpenFlow 1.0 specification, and can generate traces in about one millisecond per hop. Most network management tasks in software-defined networks (SDN) involve two stages: measurement and control. While many efforts have been focused on network control APIs for SDN, little attention goes into measurement. The key challenge of designing a new measurement API is to strike a careful balance between generality (supporting a wide variety of measurement tasks) and efficiency (enabling high link speed and low cost). We propose a software defined traffic measurement architecture OpenSketch, which separates the measurement data plane from the control plane. In the data plane, OpenSketch provides a simple three-stage pipeline (hashing, filtering, and counting), which can be implemented with commodity switch components and support many measurement tasks. In the control plane, OpenSketch provides a measurement library that automatically configures the pipeline and allocates resources for different measurement tasks. Our evaluations of real-world packet traces, our prototype on NetFPGA, and the implementation of five measurement tasks on top of OpenSketch, demonstrate that OpenSketch is general, efficient and easily programmable. Because the Internet has been widely applied in various fields, more and more network security issues emerge and catch people's attention. However, adversaries often hide themselves by spoofing their own IP addresses and then launch attacks. For this reason, researchers have proposed a lot of traceback schemes to trace the source of these attacks. Some use only one packet in their packet logging schemes to achieve IP tracking. Others combine packet marking with packet logging and therefore create hybrid IP traceback schemes demanding less storage but requiring a longer search. In this paper, we propose a new hybrid IP traceback scheme with efficient packet logging aiming to have a fixed storage requirement for each router (under 320 KB, according to CAIDA's skitter data set) in packet logging without the need to refresh the logged tracking information and to achieve zero false positive and false negative rates in attack-path reconstruction. In addition, we use a packet's marking field to censor attack traffic on its upstream routers. Lastly, we simulate and analyze our scheme, in comparison with other related research, in the following aspects: storage requirement, computation, and accuracy. Accurate and frequent round trip time (RTT) measurements are important in testbeds and operational networks. Active measurement techniques inject probe packets that may modify the behaviour of the observed network and may produce misleading RTT estimates if the network handles probe packets differently to regular packets. Previous passive measurement techniques address these issues, but require precise time synchronisation or are limited to certain traffic types. We introduce Synthetic Packet-Pairs (SPP), a novel passive technique for RTT measurement. SPP provides frequently updated RTT measurements using any network traffic already present in the network without the need for time synchronisation. SPP accurately measures the RTT experienced by any application's traffic, even applications that do not exhibit symmetric client-server packet exchanges. We experimentally demonstrate the advantages of SPP.