Selective Repeat ARQ Protocol Research Articles

A Novel Covert Channel for IEEE 802.11 Networks Utilizing MAC Address Randomization

Vendors implement the MAC address randomization technique to prevent IEEE 802.11 client station devices from being tracked. Although it conceals device identity, it cannot hide its occurring data transmission. This paper presents a novel covert channel that leverages the MAC address randomization technique to create a covert channel to hide data transmission inside IEEE 802.11 networks. The secret data are a disposable random MAC address generated by the IEEE 802.11 station as part of the probe request frame while scanning the network. The paper presents the concept of the covert channel, its implementation, and performance metrics. The study covers diverse scenarios, including the adaptation of the modified Selective Repeat ARQ protocol to alleviate the impact of the number of client stations and their offered loads on the covert channel. The results show that with the appropriate parameter selections, we can adapt the covert channel to produce excellent throughput, efficiency, delay, and jitter according to the environment in which it is installed.

Teletraffic analysis and simulation on FSO systems: the traffic generators approach

Free Space Optical Communications (FSO) has become an interesting topic to researchers in recent years since the amount of data generated by devices is growing, and it is necessary to use data links that support high bandwidth to transmit them from one device to another. This technology is used to establish not only terrestrial links but also space links.A CubeSat satellite is generally deployed in the Low Earth Orbit (LEO) region. To maintain the altitude, the satellite must have a high orbital speed. For that reason, the time to transmit data between a particular ground station and the CubeSat satellite is limited. On the other hand, the volume, mass, and energy storage capacity are restricted in a CubeSat. The greater the bandwidth capacity of radio frequency links, the greater the demand for volume, mass, and energy they require. For that reason, to transmit a significant amount of data, traditional radio frequency links are not suitable and are becoming replaced by FSO as technology improves.Despite research in physical layer technologies on FSO (modulation schemes, error mitigation techniques, pointing and tracking systems), there is very little research in the literature about data link layer protocols for FSO. Secondly, there is little research to measure the data traffic demand on CubeSat satellites so that a certain data link layer protocol can be selected or adapted to be implemented in an FSO system.This paper presents research to address the issue of teletraffic through the use of traffic generators. The result is the design and development of a traffic generator for a discrete event simulator that will later be used to observe the behavior and to measure the performance of the Selective Repeat ARQ protocol in a simulated satellite FSO link, in order to propose improvements to adapt the protocol to this scenario.

Overload Control with Hybrid SIP Signaling - Using Smart Reliability and Priority Queuing Strategies

Session Initiation Protocol is an IP based application level signaling protocol. SIP employs request retransmission for enabling reliability over UDP transport. This research work proposes a Hybrid SIP System that integrates the congestion control techniques from the proposed Smart Reliable SIP and Overload control using Advanced Smart Priority (ASP) Queuing Strategy. The proposed system reduces retransmissions and queuing delays in SIP servers. Smart Reliable SIP (SRSIP) implements the modified Selective Repeat ARQ protocol for enabling reliability of SIP requests without violating the SIP core functionality. SRSIP reduces the number of retransmissions. ASP Queuing Strategy prioritizes the SIP requests based on the retransmissions. The proposed system reduces the queuing delays for request processing at the downstream server and the retransmissions over the network. The Hybrid models integrates the features of both Smart Reliable SIP and ASP queuing strategy resulting in a system with almost zero retransmissions and reduced queuing delay for request processing.

Tiny Codes for Guaranteeable Delay

Future 5G systems will need to support ultra-reliable low-latency communications scenarios. From a latency-reliability viewpoint, it is inefficient to rely on average utility-based system design. Therefore, we introduce the notion of guaranteeable delay which is the average delay plus three standard deviations of the mean. We investigate the trade-off between guaranteeable delay and throughput for the point-to-point wireless erasure links with unreliable and delayed feedback, by bringing together signal flow techniques to the area of coding. We use tiny codes, i.e., sliding window by coding with just 2 packets, and design three variations of selective-repeat ARQ protocols, by building on the baseline scheme, i.e., uncoded ARQ, developed by Ausavapattanakun and Nosratinia: (i) Hybrid ARQ with soft combining at the receiver; (ii) cumulative feedback-based ARQ without rate adaptation; and (iii) coded ARQ with rate adaptation based on the cumulative feedback. Contrasting the performance of these protocols with uncoded ARQ, we demonstrate that the HARQ performs only slightly better, the cumulative feedback-based ARQ does not provide significant throughput while it has a better average delay, and the Coded ARQ can provide gains up to about 40% in terms of throughput. The Coded ARQ also provides delay guarantees, and is robust to various challenges such as imperfect and delayed feedback, burst erasures, and round-trip time fluctuations. This feature may be preferable for meeting the strict end-to-end latency and reliability requirements of the future use cases of ultra-reliable low-latency communications in 5G, such as mission-critical communications and industrial control for critical control messaging.

On modelling network coded ARQ-based channels

Network coding (NC) offers throughput improvements by algebraically combining multiple input packet streams which address one output port at an intermediate node. We present a practical implementation of NC with error control, namely stop-and-wait automatic repeat request (SW ARQ). We apply a modified NC scheme at an intermediate SW ARQ-based link to reduce ARQ control signals and then extend this to NC in a butterfly multicast network which adopts the selective repeat (SR) ARQ protocol as its error control scheme. We validate our throughput analysis using a relatively recent discrete-event simulator, SimEvents®. The results show a throughput advantage of at least 50%, particularly in the presence of high error rates. In the multicast SR ARQ network, NC-SR ARQ effectively doubles the throughput compared with the traditional scheme and increases the protocol’s ability to deal with propagation times that are long in comparison with the packet inter-arrival time.

Performance Evaluation of Some Dynamic ARQ Schemes for Multichannel Communication System

In this paper, we propose two dynamic error control schemes and apply them to the multichannel data communication system. The proposed schemes are based on the basic Stop-and-Wait ARQ and Selective Repeat ARQ protocols, The former and latter are used for the error controls in a round-trip time and among the multiple channels in a slot, respectively. The state of each channel is assumed as Markov chain with two states. The operations of the proposed schemes are described and their performances are evaluated through computer simulation. The numerical results show that the performances of the proposed schemes are improved remarkably comparing with the traditional scheme.

Optimal design of hybrid FEC/ARQ schemes for TCP over wireless links with Rayleigh fading

In this paper, we investigate interactions between TCP and wireless hybrid FEC/ARQ schemes. The aim is to understand what is the best configuration of the wireless link protocol in order to guarantee TCP performance and channel efficiency. Interactions between TCP and different link layer mechanisms are evaluated by means of an analytic model that reproduces: 1) a Rayleigh fading channel with FEC coding, 2) a generic selective repeat ARQ Protocol, and 3) the TCP behavior in a wired-cum-wireless network scenario. The analytic model is validated-by means of ns-based simulations. The analysis represents a contribution to the optimal design of link layer parameters of wireless networks crossed by TCP/IP traffic. The main findings can be summarized as follows: 1) fully reliable ARQ protocols are the best choice for both TCP performance and wireless link efficiency and 2) optimal values of FEC redundancy degree from the point of view of energy efficiency maximizes TCP performance as well.

Novel methods for the performance analysis of adaptive hybrid selective repeat ARQ

In this paper we present two novel approximation methods for the performance analysis of selective repeat (SR) ARQ protocol with any size of buffer. The methods are called sequential method (SM) and stable function method (SFM). Both SM and SFM methods provide highly accurate results as compared to other conventional methods of analysis. However, between SM and SFM methods, it is observed that SM is computationally more complex. Hence, SFM method is proposed for our analysis. Based on SFM, we present an ad hoc algorithm for an adaptive SR ARQ scheme to optimize the performance of SR ARQ. The performance of hybrid SR ARQ (an SR ARQ protocol combined with FEC) is also analyzed. It is concluded from a comparison of different methods of analyzing the SR ARQ protocol that the stable function method (SFM) provides a simple and novel approach for network analysis.

Selective repeat receiver delay, with application to SSCOP

A new approach is presented for calculating the receiver delay for the selective repeat ARQ protocol. This result enables the delay performance of the SSCOP protocol proposed for the ATM adaptation layer to be calculated.

End-to-end delay of an adaptive selective repeat ARQ protocol

This paper analyzes the end-to-end delay of a selective-repeat ARQ protocol which tries to adaptively use the channel idle time. The end-to-end delay consists of three parts: queueing delay at the transmitter, transmission delay over the channel, and resequencing delay at the receiver. Although this paper succeeds only in obtaining approximate end-to-end delay, the agreement with simulation is generally good. >

Multichannel ARQ protocols

The performance of stop-and-wait, go-back-N, and selective-repeat ARQ protocols is examined for a multichannel system. The channels can either operate independently or jointly. For each protocol, the results obtained include throughput efficiency and delay. The results are also validated by computer simulations. The performance is compared to that of the single-channel system under the constraint of fixed total capacity. It is observed that the multichannel system has a chance to outperform the single-channel system.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Dynamic programming for optimization of system throughput with application to selective-repeat ARQ protocols over broadcast channels

This paper studies packet network data link layer error control protocols suitable for point-to-multipoint communication. We optimize the throughput performance of two new selective-repeat protocols which differ in the way the sender uses the outcomes of the previous transmission. In both protocols, multiple copies of a data frame are sent (instead of just a single copy). The optimum number of copies is determined based on how many receivers have not yet received the data frame. A dynamic programming technique is used to solve this optimization problem. The results show that by sending the optimum number of copies of a data frame instead of just a single copy, the throughput will be significantly improved.

Receiver buffer behavior for the selective-repeat ARQ protocol

It is well known that the Selective-Repeat ARQ protocol has, among all error detection and retransmission schemes, the best throughput efficiency. However, this protocol has the disadvantage that data blocks may be received out of order, such that some reordering is required at the receiver side, before the blocks can be delivered to their destination. In order to accomplish this reordering, the receiver must dispose of a theoretically infinite amount of buffer space for the storage of correctly received blocks which cannot be delivered yet. The purpose of the paper is to study the statistical behavior of this receiver buffer, under the assumption of independent transmission errors. The study results in an explicit expression for the probability generating function of the number of blocks stored in the receiver buffer (observed at the discrete time epochs when blocks arrive at the receiver side), under the (worst-case) assumption that data blocks are available without interruption at the transmitter side. From this expression several interesting characteristics, such as the mean and variance of the buffer occupancy and the overflow probability of the buffer (if finite) can be derived with arbitrary accuracy.

A Statistical Analysis of ARQ Protocols Operating in a Nonindependent Error Environment

In this paper the behavior of the Stop and Wait and Go Back- <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</tex> error detection and retransmission (ARQ) protocols in an environment characterized by nonrandom errors are studied. Analytic models are developed for the case that the error process is modeled as a Markovian process. These models may be used to predict performance measures such as expected queue length and expected delay for the case of the Stop and Wait protocol and the Go Back- <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</tex> protocol when <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</tex> is very large. The models can also be used to determine maximum throughputs for both protocols. The results of these models are compared with simulation results for the Selective Repeat ARQ protocol.