Prioritized Retransmission: A TCP Flow Control Mechanism

Now-a-days, efforts have been made in the research of transmission control protocols to improve the performance of the flow control mechanism. Internet communication and services daily increase the variety and quantity of their capacity and needs. Therefore the flow control mechanism will have to consider valuable for traffic control, especially on high-speed networks. Initially there are some challenges, for instance, loss of packet, processing capacity, performance, buffer overflows and deadlocks with which daily traffic is confronted. This paper analyzes and reviewed the strengths and weaknesses of the different flow control mechanisms used in TCP. To overcome the weaknesses of these flow controls, we suggest a priority retransmission mechanism. Here we have priority on the Negative Acknowledgment (NACK), we resend the package on the basis of the minimum sequence number of the NACK. In buffer of priority retransmission Automatic Repeat request (ARQ) mechanism, the packet is released to the communication link in a First in First out (FIFO) manner. That is why the priority retransmission ARQ gives the optimum performance

STABILITY ANALYSIS AND SIMULATION OF N-CLASS RETRIAL SYSTEM WITH CONSTANT RETRIAL RATES AND POISSON INPUTS

In this paper, we study a new retrial queueing system with N classes of customers, where a class-i blocked customer joins orbit i. Orbit i works like a single-server queueing system with (exponential) constant retrial time (with rate [Formula: see text]) regardless of the orbit size. Such a system is motivated by multiple telecommunication applications, for instance wireless multi-access systems, and transmission control protocols. First, we present a review of some corresponding recent results related to a single-orbit retrial system. Then, using a regenerative approach, we deduce a set of necessary stability conditions for such a system. We will show that these conditions have a very clear probabilistic interpretation. We also performed a number of simulations to show that the obtained conditions delimit the stability domain with a remarkable accuracy, being in fact the (necessary and sufficient) stability criteria, at the very least for the 2-orbit M/M/1/1-type and M/Pareto/1/1-type retrial systems that we focus on.

Performance Analysis of Traffic and Mobility Models on Mobile and Vehicular Ad Hoc Wireless Networks

Advances in wireless communication technology and the proliferation of mobile devices enable the capabilities of communicating with each other even in areas with no pre-existing communication infrastructure. Traffic and mobility models play an important role in evaluating the performance of these communication networks. Despite criticism and assumption from various researches on Transmission Control Protocols (TCP), weaknesses on Mobile Ad Hoc Network (MANET), and Vehicular Ad Hoc Network (VANET). A simulation was carried out to evaluate the performance of Constant Bit Rate, Variable Bit Rate and Transmission Control Protocol on MANET and VANET using DSR routing protocol. CBR, VBR, and TCP have different manufacturer operation mechanisms and these differences lead to significant performance of CBR and VBR over TCP with better throughput and less average maximal end-to-end delay. DSR was able to respond to link failure at low mobility which led to TCP’s performance in packets delivery.

IBperf: A Testing and Evaluation Model of IB Datacenter Transmission Control

Datacenter is the important infrastructure to provide resource and service in Internet. Due to the widely observed congestion, all kinds of transmission control mechanisms have been proposed to satisfy diverse network performance demands. Based on InfiniBand (IB) which is widely applied for datacenter construction, this paper proposed a generic testing and evaluation platform IBperf to verify transmission control protocols. We designed a central controller to instruct distributed clients to generate different communication patterns and execute commands of the protocol. The transmission performance can be derived based on the captured packets and digest. In the experiment, IB congestion control (CC) was evaluated through IBperf on our real IB platform. IBperf showed the improvement of fairness and throughput with low overhead based on CC mechanism. It proved IBperf to be an effective tool for the evaluation of IB datacenter.