Performance analysis of Packet Loss Concealment in mobile environments with a two-state loss model

Trans Emerging Tel Tech

2018

The Constrained Application Protocol (CoAP) has been instrumental to the deployment of wireless sensors and actuators in Internet of Things low‐power low‐rate networks. Typically, a large number of such devices interact with a single gateway that routes traffic to servers where complex processing is performed. CoAP provides a highly efficient end‐to‐end mechanism that relies on the User Datagram Protocol for transport, and it is characterized by both low throughput and low latency. Because Internet firewalls typically filter User Datagram Protocol traffic as it traverses from gateways to servers, the use of Transmission Control Protocol (TCP) encapsulation becomes a viable alternative. This solution, however, is negatively affected by network packet loss that, due to TCP inherent retransmissions, severely degrades latency, reducing system responsibility. In this paper, we analyze the effect of TCP‐encapsulated CoAP and propose a mechanism that overcomes these limitations without having to change network topologies or modifying protocol functionality.

P_{low} = \frac{1 - α}{1 - α + p}

and

P_{high} = \frac{p}{1 - α + p}

.…”

Section: Theoretical Frameworkmentioning

confidence: 99%

Section: Coap Encapsulationmentioning

confidence: 99%

Encapsulation of real‐time IoT CoAP traffic

Trans Emerging Tel Tech

2018

“…The analytical model presented in [11] is based on Figure 1. The two states represent the channel in either a low loss (L) state or a high loss (H) state.…”

Section: Theoretical Analysismentioning

confidence: 99%

“…They specifically focus (2) packet XORing applied to generic RTP traffic. In this paper we extend [11] by applying those FEC techniques to real speech traffic (involving multiple LBR and DTX) and comparing theoretical results to experimental RTP packet loss as well as the perceived speech quality by means of PESQ scores [12] [13].…”

Section: Introductionmentioning

confidence: 99%

“…The characteristics of fading channels are a well known phenomenon and their statistics have been modeled by a two-state Markov process [10]. In [11] the authors derive a mathematical model to compute the RTP packet loss as a function of the Markov process parameters when different FEC mechanisms are used. They specifically focus (2) packet XORing applied to generic RTP traffic.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of FEC mechanisms in the performance of low bit rate codecs in lossy mobile environments

Proceedings of the Conference on Principles, Systems and Applications of IP Telecommunications

Cadirola²

2014

In this paper we focus on Forward Error Correction (FEC) mechanisms based on media redundancy applied to various Low Bit Rate (LBR) speech codecs in the context of lossy mobile environments. Specifically, we deal with different state of the art linear prediction based codecs ranging from narrowband G.729AB and AMR-NB to wideband Opus and SILK, all of them enabled to support Discontinued Transmission (DTX) mode, and packetized over switched networks as RTP/UDP/IP traffic. We evaluate these speech codecs applied in conjunction with media redundancy techniques to a network scenario where packet loss bursts and latency are induced to mimic mobile environments that are normally mathematically modeled as a two-state Markov process. In addition to obtaining the application layer packet loss and comparing it to the mathematical model we also compute the Perceptual Evaluation of Speech Quality (PESQ) score in an attempt to correlate packet loss to real perceived speech quality.

6LoWPAN fragmentation in the context of IoT based media real time communication

Internet Technology Letters

2020

Many Internet of Things (IoT) applications, like presence detection, rely on wireless sensors transmitting Real Time Communication (RTC) media that is processed at remote servers. The use of IEEE 802.15.4 physical and data‐link layers is pretty widespread as they provide enough throughput to transmit compressed media. In this context, however, the most important issue is that IEEE 802.15.4 limits the Maximum Transmission Unit (MTU) size to 127 bytes. The Low power Wireless Personal Area Networks (6LoWPAN) IPv6 adaptation protocol provides a mechanism that adds fragmentation capabilities to traditional IPv6 and allows the transmission of typically large media frames. Because it is not always possible to configure codec based fragmentation, alternatively relying on 6LoWPAN fragmentation can severely affect Quality of Service (QoS) when the wireless channel exhibits high packet loss. In this paper we focus on analyzing this problem including its implications and proposing possible solutions.