Network Coding Over SATCOM: Lessons Learned

Satellite networks provide unique challenges that can restrict users' quality of service. For example, high packet erasure rates and large latencies can cause significant disruptions to applications such as video streaming or voice-over-IP. Network coding is one promising technique that has been shown to help improve performance, especially in these environments. However, implementing any form of network code can be challenging. This paper will use an example of a generation-based network code and a sliding-window network code to help highlight the benefits and drawbacks of using one over the other. In-order packet delivery delay, as well as network efficiency, will be used as metrics to help differentiate between the two approaches. Furthermore, lessoned learned during the course of our research will be provided in an attempt to help the reader understand when and where network coding provides its benefits.Comment: Accepted to WiSATS 201

Analysis of an Adaptive Modulation and Coding scheme with HARQ for TCP traffic

In this paper, we analyze the aggregate TCP throughput performance of a wireless link utilizing Active Queue Management (AQM) and an Adaptive Modulation and Coding (AMC) scheme with Hybrid ARQ (HARQ) based on the probability of failure in the first transmission attempt. We assume packets arriving out-of-order at the wireless receiver due to random retransmissions are resequenced before being released to the network. For this reason, an approximate model for the delay experienced at the resequencing buffer is also presented. In the light of the results obtained from the presented analysis, we propose a threshold for the aforementioned probability of failure making the investigated AMC scheme work at an overall performance close to that of the optimum policy. © 2015 IEEE

Performance analysis of poll-based retransmission schemes

Caption title.Includes bibliographical references (p. 23).Supported by the NSF, DARPA and ATT Bell Laboratories.Jane M. Simmons

Some Results on the Statistics of Delay Terms in SR ARQ on Markov Channels

Abstract-In this paper we explore the packet delay statistics of a Selective Repeat ARQ scheme on a Discrete Time Markov Channel with non-instantaneous round trip delay. In particular, we are interested in obtaining considerations about the queueing delay of the process and also possible comparisons between different delay components. For this reason, we analyze in detail the impact of system parameters, such as the packet arrival rate and the packet error probability, on the terms which constitute the overall delay. Finally, we explore the connection of these numerical evaluations with the QoS requirements connected to delay for multimedia traffic

Analysis of ARQ protocols for bacterial quorum communications

Quorum sensing (QS) is used to describe the communication between bacterial cells, whereby a coordinated population response is controlled through the synthesis, accumulation and subsequent sensing of specific diffusible chemical signals called autoinducers, enabling a cluster of bacteria to regulate gene expression and behaviour collectively and synchronously, and assess their own population. As a promising method of molecular communication, bacterial populations can be programmed as bio-transceivers to establish information transmission using molecules. In this work, to investigate the key features for molecular communication, a bacterial QS system is introduced, which contains two clusters of bacteria, specifically Vibrio fischeri, as the transmitter node and receiver node, and the diffusive channel. The transmitted information is represented by the concentration of autoinducers with on–off keying (OOK) modulation. In addition, to achieve better reliability, transmission efficiency and channel throughput performance, different Automatic Repeat reQuest (ARQ) protocols are taken into consideration. This configuration is investigated via simulation and the consequent results discussed. The performance of the system is evaluated in terms of transmission time, efficiency, bit error rate (BER) and channel throughput. Results show that Selective-Repeat (SR-ARQ) performs better than Go-Back-N (GBN-ARQ), while the performance of Stop-N-Wait (SW-ARQ) varies for different channel conditions, which is quite different from the performance of ARQ schemes in traditional networking areas