DCCP Protocols Research Articles

Performance Evaluation of UDP, DCCP and TCP in Congested Wired Networks

Communication through the internet is one of the dominant methods of exchanging information. TCP and UDP are the transport layer protocols responsible for transit of nearly all Internet communications. Due to the growth of real-time audio and video applications, UDP is being used more frequently as a transport protocol, but unlike TCP, UDP has no mechanism for congestion control leading to wasted bandwidth and poor performance, so the DCCP protocol has appeared as a replacement for UDP. In this article, the author performs some simulations using NS2 for Drop Tail and RED queuing models to evaluate the performance of TCP, UDP, DCCP CCID2, and DCCP CCID3 protocols in congested wired networks. The performance metrics used are throughput, end to end delay, number of sent and lost packets. The obtained results show that the DCCP CCID2 performs the best throughput with the minimum of delay as compared to UDP, TCP, and DCCP CCID3.

Congestion Control in WMSNs by Reducing Congestion and Free Resources to Set Accurate Rates and Priority

The main intention of this paper is focus on mechanism for reducing congestion in the network by free resources to set accurate rates and priority data needs. If two nodes send their packets in the shortest path to the parent node in a crowded place, a source node must prioritize the data and uses data that have lower priorities of a suitable detour nodes consisting of low or nonactive consciously. The proposed algorithm is applied to the nodes near the base station (which convey more traffic) after the congestion detection mechanism detected the congestion. Obtained results from simulation test done by NS-2 simulator demonstrate the innovation and validity of proposed method with better performance in comparison with CCF, PCCP and DCCP protocols.

Unreliable transport protocol using congestion control for high-speed networks

Currently there is no control for the real-time traffic of multimedia applications using UDP (User Datagram Protocol) in high-speed networks. Therefore, although a number of high-speed TCP (Transmission Control Protocol) protocols have been developed for gigabit-speed (or faster) links, the real-time traffic could also congest the network and result in unfairness and throughput degradation of TCP traffic. In this paper, a new unreliable transport protocol, FAST DCCP, is presented for the real-time traffic in high-speed networks. FAST DCCP is based on the DCCP protocol and adopts the FAST scheme to realize congestion control. Some modifications have been made to the mechanisms inherited from DCCP so as to let the proposed protocol can efficiently operate under a large size window. In addition, an enhanced protocol, EEFAST DCCP, using the measurements of one-way delay to dynamically adjust the window size is also proposed to improve the throughput of FAST DCCP with the effect of reverse traffic. Simulation results show that FAST DCCP not only can satisfy the requirements of real-time data delivery, but also perform well in bandwidth utilization and fairness in high-speed networks. Meanwhile, EEFAST DCCP is able to effectively conquer the throughput degradation caused by the reverse traffic.

Passing Corrupt Data Across Network Layers: An Overview of Recent Developments and Issues

Recent Internet developments seem to make a point for passing corrupt data from the link to the network layer and above instead of ensuring data integrity with a checksum and ARQ. We give an overview of these efforts (the UDP Lite and DCCP protocols) and explain which circumstances would justify delivery of erroneous data; clearly, the missing piece in the puzzle is efficient and meaningful interlayer communication.