Abstract
The flexibility of cognitive and software-defined radio heralds an opportunity for researchers to reexamine how network protocol layers operate with respect to providing quality of service aware transmission among wireless nodes. This opportunity is enhanced by the continued development of spectrally responsive devices—ones that can detect and respond to changes in the radio frequency environment. Present wireless network protocols define reliability and other performance-related tasks narrowly within layers. For example, the frame size employed on 802.11 can substantially influence the throughput, delay, and jitter experienced by an application, but there is no simple way to adapt this parameter. Furthermore, while the data link layer of 802.11 provides error detection capabilities across a link, it does not specify additional features, such as forward error correction schemes, nor does it provide a means for throttling retransmissions at the transport layer (currently, the data link and transport layer can function counterproductively with respect to reliability). This paper presents an analysis of the interaction of physical, data link, and network layer parameters with respect to throughput, bit error rate, delay, and jitter. The goal of this analysis is to identify opportunities where system designers might exploit cross-layer interactions to improve the performance of Voice over IP (VoIP), instant messaging (IM), and file transfer applications.
Highlights
The flexibility of cognitive and software-defined radios presents an opportunity for researchers to reexamine how network protocol layers operate with respect to providing quality of service aware transmission among wireless nodes
Our work demonstrates that even conservative adaptation of the Advances in Multimedia physical, data link, and network layers will provide significant enhancement to the performance of the system, and that adaptation can strongly influence the ability of the system to meet quality of service (QoS) requirements
Stop-and-wait is the type of Automatic repeat request (ARQ) used, wherein the sending node will stop transmitting until it has received an acknowledgment from the receiver
Summary
The flexibility of cognitive and software-defined radios presents an opportunity for researchers to reexamine how network protocol layers operate with respect to providing quality of service aware transmission among wireless nodes. This opportunity is enhanced by the continued development of spectrally responsive devices—ones that can detect and respond to changes in the radio frequency environment. We look at (1) power, (2) bitrate, (3) forward error correction, (4) frame size, (5) automatic repeat request, and (6) selective queueing The goal of this analysis is to identify key opportunities for system designers to exploit cross-layer interactions improving the performance of Voice over IP (VoIP), instant messaging (IM), or file transfer applications. Very active, has begun to give way to the recent popularity of cognitive radio
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
