An Analytical Approach for Throughput Evaluation of Wireless Network Coding

Abstract

In this paper, we propose a new analytical model for stable throughput evaluation of wireless network coding. In this new approach we consider the arrival and departure rates in and from the wireless nodes, respectively, in steady state. Our analytical model is founded on a multi-class open queueing network. In this model, we include two basic processes of network coding, i.e., packets combination and packets multicasting, in a suitable manner considering the constraints of the queueing networks. In this respect, we consider the coded packets as new classes of customers. By solving the related traffic equations and applying the stability condition, we compute the maximum stable throughput, i.e., the maximum packet generation rate at which the packets reach their destinations with finite delays. We apply our approach to a symmetric WLAN with unicast flows and a slotted random access MAC scheme, and compute the maximum stable throughputs for the cases of simple routing and network coding, distinctly. Finally, we confirm our analytical results by simulation.

Performance Analysis of Network Coding with IEEE 802.11 DCF in Multi-Hop Wireless Networks

“…7 shows that the end-to-end delay is also an increasing function of the packet generation rate. As explained earlier, this is due to the fact that generating new packets faster increases the number of packets queued to be transmitted, which means longer waiting time in the queues, as confirmed by (13).…”

“…Prior theoretical studies on network coding usually consider a simple topology. Most of them study the performance for a two-way relay [6], [7], [8], [14], or derive some analytical bounds for a single relay in a two-hop region, where multiple sources initiate unicast sessions to multiple destinations [9], [10], [11], [12], [13], [15]. In particular, Amerimehr and Ashtiani [7] study the throughput and delay of a two-way relay by adopting frequency division duplexing (FDD).…”

“…Some previous theoretical studies are designed for saturated queues, where each node always has a packet to transmit that would cause an infinite delay. In many cases, researchers consider a simple topology, where source is one [2], [3], [4], [5] or two [6], [7], [8], [9], [10], [11], [12], [13], [14], [15] hops away from the destination. Furthermore, the theoretical research on multi-hop networks [16], [17], [18], [19], [20], [21] usually models network coding with simplifying assumptions, such as conflict-free scheduled access, no interference, no collision, or no exponential back-off.…”

“…It applies random medium access CSMA/CA as in IEEE 802.11 Distributed Coordination Function (DCF) with binary exponential back-off considering clock freezing and virtual carrier sensing as explained in Sections 3.2 and 4.1.2. We consider retransmission, collision probability, link qualities and coding probabilities in calculating the throughput and an upper-bound of average end- [2], [3] √ 1 √ -√ √ multicast -- [4], [5] [9], [12], [13]…”

“…2) We develop our analytical framework for both noncoding and coding schemes in multi-hop wireless networks, and formulate not only the throughput but also the end-to-end delay in a stable network. [2], [3] √ [12], [13] √…”