Improving wireless multicast communications with NC: Performance assessment over a COTS platform

Abstract

Multicast services are believed to play a relevant role in next wireless networking scenarios. In this paper we exploit Tunable Sparse Network Coding techniques to increase reliability of multicast communications. We show that the proposed network coding scheme yields a better performance than state-of-the-art solutions, which are traditionally based on retransmissions. We first use a model to analytically compare the two approaches. Then, we validate and broaden this analysis by means of an experimental campaign over a testbed deployed with Commercial Of-The-Shelf devices. This platform, comprising low cost devices (Raspberry-PI), allows us to assess the feasibility of the proposed solution, which offers a relevant gain in terms of performance.

Multirate Packet Delivery in Heterogeneous Broadcast Networks

“…4. To calculate delivery rate, (4) is used for the leader probability and (10)- (12) have been used for the probability of leader transmissions, then the differential knowledge probabilities are given by (13), (14) and the delivery rate is given by (3). In all settings, it is observed that the users in group H have reached the delivery rate of λ, and for the users in L, there is a reasonable match between the simulation and analytical results.…”

“…Note that the summation in (13) represents the probability that U i has not seen the requested packet by U h while U h has been the leader. Similarly, in (14) when H = Ø, the summation is the same probability while U l has been the leader.…”

“…Assuming that these packets are uniformly distributed, we have: Table III. In calculation of the delivery rate, β h is given by (4), differential knowledges are given by (13) and (14) and the delivery rate is given by (3).…”

“…An efficient method to accommodate multiple users' demands, achieving high throughput and decreasing delay is network coding [6]- [9]. This method has been studied in different types of networks such as multicast and unicast networks [9]- [13], multiple access and relay networks [14]- [17] as it is used to exploit the broadcast property of wireless channels and also to combat the packet erasure problem in networks [18]- [23].…”