Pervasive intelligent routing in content centric delay tolerant networks

This paper introduces a Swarm-Intelligence based Routing protocol (SIR) that aims to efficiently route information in content centric Delay Tolerant Networks (CCDTN) also dubbed pocket switched networks. First, this paper formalizes the notion of optimal path in CCDTN and introduces an original and efficient algorithm to process these paths in dynamic graphs. The properties and some invariant features of these optimal paths are analyzed and derived from several real traces. Then, this paper shows how optimal path in CCDTN can be found and used from a fully distributed swarm-intelligence based approach of which the global intelligent behavior (i.e. shortest path discovery and use) emerges from simple peer to peer interactions applied during opportunistic contacts. This leads to the definition of the SIR routing protocol of which the consistency, efficiency and performances are demonstrated from intensive representative simulations

Data Bit-Rate Instability in Wireless Multi-Rate Ad Hoc Networks

Wireless Ad-hoc single-rate environments typically use a Distance Vector routing with a metric based on the minimization of the hop-count. In practice, the technique of minimizing the distance does not reward in the case of multi-rate, therefore it may be prefereable touse protocols privileging the link's transmission speed instead of the minimum distance. Our study aims toward the stability of the link in a wireless high mobility environment; we explore and hypothesize how to privilege, in the choice of routes, the stablest link.Ad Hoc Networks; Routing; Stability.

Link Stability inWireless Multi-Rate Ad Hoc Networks

Wireless ad hoc single-rate environments typically use a Distance Vector routing with a metric based on hop-count minimization. In practice, the technique of minimizing the distance does not reward in the case of multirate, therefore it may be prefereable to use protocols privileging link stability instead of speed and minimum distance. We study link stability in a wireless high mobility environment and propose a Route Discovery mechanism privileging the stablest link.VPN; Network; Protocol.

Cryptographic Energy Costs are Assumable in Ad Hoc Networks

Performance of symmetric and asymmetric cryptography algorithms in small devices is presented. Both temporal and energy costs are measured and compared with the basic functional costs of a device. We demonstrate that cryptographic power costs are not a limiting factor of the autonomy of a device and explain how processing delays can be conveniently managed to minimize their impact

Maximizing the Probability of Delivery of Multipoint Relay Broadcast Protocol in Wireless Ad Hoc Networks with a Realistic Physical Layer

It is now commonly accepted that the unit disk graph used to model the physical layer in wireless networks does not reflect real radio transmissions, and that the lognormal shadowing model better suits to experimental simulations. Previous work on realistic scenarios focused on unicast, while broadcast requirements are fundamentally different and cannot be derived from unicast case. Therefore, broadcast protocols must be adapted in order to still be efficient under realistic assumptions. In this paper, we study the well-known multipoint relay protocol (MPR). In the latter, each node has to choose a set of neighbors to act as relays in order to cover the whole 2-hop neighborhood. We give experimental results showing that the original method provided to select the set of relays does not give good results with the realistic model. We also provide three new heuristics in replacement and their performances which demonstrate that they better suit to the considered model. The first one maximizes the probability of correct reception between the node and the considered relays multiplied by their coverage in the 2-hop neighborhood. The second one replaces the coverage by the average of the probabilities of correct reception between the considered neighbor and the 2-hop neighbors it covers. Finally, the third heuristic keeps the same concept as the second one, but tries to maximize the coverage level of the 2-hop neighborhood: 2-hop neighbors are still being considered as uncovered while their coverage level is not higher than a given coverage threshold, many neighbors may thus be selected to cover the same 2-hop neighbors