A content can be replicated in more than one node, in Information Centric Networks (ICNs). Thus, more than one path can be followed to reach the same content, and it is necessary to decide the interface(s) to be selected in every network node to forward content requests towards such multiple content containers. A multipath forwarding strategy defines how to perform this choice. In this paper we propose a general analytical model to evaluate the effect of multipath forwarding strategies on the performance of an ICN content delivery, whose congestion control follows a receiver driven, loss-based AIMD scheme. We use the model to understand the behavior of ICN multipath forwarding strategies proposed in the literature so far, and to devise and evaluate a novel strategy. The considered multipath forwarding strategies are also evaluated in a realistic network setting, by using the PlanetLab testbed.
Congestion control is an open ICN issue and there is not yet a standard'' protocol. Out of delivery may frequently happen in ICN, due to in-network caching and per-packet multipath forwarding strategies. Thus, recent works suggest to use receiver-driven congestion control schemes that do not consider out of order delivery as a symptom of congestion, but rather infer congestion from other parameters such as increasing delay (delay-based congestion control) @cite_4 @cite_1 , and packet loss (loss-based congestion control) @cite_19 @cite_0 . However, it is not clear, yet, which is the best indicator for congestion. In @cite_18 the authors raise concerns about delay-based approaches due to the small correlation between increased delays (or RTTs) and congestion-related losses in wired Internet measurements. Conversely, it is well-known that loss-based congestion control dramatically suffers from the random packet loss of wireless environments @cite_10 . In any case, the receiver-driven and connectionless nature of ICN congestion control enables receivers to select the best approach, depending on actual conditions.
@cite_18 @cite_4 @cite_1 @cite_0 @cite_19 @cite_10
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The fast-growing Internet traffic is increasingly becoming content-based and driven by mobile users, with users more interested in data rather than its source. This has precipitated the need for an information-centric Internet architecture. Research in information-centric networks (ICNs) have resulted in novel architectures, e.g., CCN NDN, DONA, and PSIRP PURSUIT; all agree on named data based addressing and pervasive caching as integral design components. With network-wide content caching, enforcement of content access control policies become non-trivial. Each caching node in the network needs to enforce access control policies with the help of the content provider. This becomes inefficient and prone to unbounded latencies especially during provider outages. In this paper, we propose an efficient access control framework for ICN, which allows legitimate users to access and use the cached content directly, and does not require verification authentication by an online provider authentication server or the content serving router. This framework would help reduce the impact of system down-time from server outages and reduce delivery latency by leveraging caching while guaranteeing access only to legitimate users. Experimental simulation results demonstrate the suitability of this scheme for all users, but particularly for mobile users, especially in terms of the security and latency overheads. In this paper we investigate the potential benefits of coordinated congestion control for multipath data transfers, and contrast with uncoordinated control. For static random path selections, we show the worst-case throughput performance of uncoordinated control behaves as if each user had but a single path (scaling like log(log(N)) log(N) where N is the system size, measured in number of resources). Whereas coordinated control gives a throughput allocation bounded away from zero, improving on both uncoordinated control and on the greedy-least loaded path selection of e.g. Mitzenmacher. We then allow users to change their set of routes and introduce the notion of a Nash equilibrium. We show that with RTT bias (as in TCP Reno), uncoordinated control can lead to inefficient equilibria. With no RTT bias, both uncoordinated or coordinated Nash equilibria correspond to desirable welfare maximising states. Moreover, simple path reselection polices that shift to paths with higher net benefit can find these states. High-speed networks with large delays present a unique environment where TCP may have a problem utilizing the full bandwidth. Several congestion control proposals have been suggested to remedy this problem. The existing protocols consider mainly two properties: TCP friendliness and bandwidth scalability. That is, a protocol should not take away too much bandwidth from standard TCP flows while utilizing the full bandwidth of high-speed networks. This work presents another important constraint, namely, RTT (round trip time) unfairness where competing flows with different RTTs may consume vastly unfair bandwidth shares. Existing schemes have a severe RTT unfairness problem because the congestion window increase rate gets larger as the window grows ironically the very reason that makes them more scalable. RTT unfairness for high-speed networks occurs distinctly with drop tail routers for flows with large congestion windows where packet loss can be highly synchronized. After identifying the RTT unfairness problem of existing protocols, This work presents a new congestion control scheme that alleviates RTT unfairness while supporting TCP friendliness and bandwidth scalability. The proposed congestion control algorithm uses two window size control policies called additive increase and binary search increase. When the congestion window is large, additive increase with a large increment ensures square RTT unfairness as well as good scalability. Under small congestion windows, binary search increase supports TCP friendliness. The simulation results confirm these properties of the protocol. ICN CCN advocates ubiquitous in-network caching to enhance content distribution. Non-safety application in vehicular communication is emerging beyond the initial safety application. However, it suffers from a typical issue of low delivery ratio in urban environments, where high buildings block and attenuate the radio propagation from RSU infrastructures as well as other technical issues. In this paper, LCE in-network caching strategy with LRU algorithm in vehicular networks is proposed according to traffic characteristics in metropolitan areas. We compare this scheme with the legacy TCP IP based scheme by simulation tools of OMNeT++ & Veins and SUMO. The simulation results validate that the proposed scheme could achieve stronger robustness against obstacles, higher file capture rate and less dependency on RSU infrastructure.