Improving the fairness of FAST TCP to new flows

It has been observed that FAST TCP, and the related protocol TCP Vegas, suffer unfairness when many flows arrive at a single bottleneck link, without intervening departures. We show that the effect is even more marked if a new flow arrives when existing flows share bandwidth fairly, and propose a simple method to ameliorate this effect

Error-aware and energy-efficient routing approach in MANETs

The lifetime of a network is the key design, factor of mobile ad hoc networks (MANETs). To prolong the lifetime of MANETs, one is forced to attain a tradeoff of minimizing the energy consumption and load balancing. In MANETs, energy waste resulting from retransmission due to high bit error rate (BER) and high frame error rate (FER) of wireless channel is significant. In this paper, we propose two novel protocols termed multi-threshold routing protocol (MTRP) and enhanced multi-threshold routing protocol (EMTRP). MTRP divides the total energy of a wireless node into multiple ranges. The lower bound of each range corresponds to a threshold. The protocol iterates from the highest threshold to the lowest one and chooses those routes with bottleneck energy being larger than the current threshold during each iteration. This approach thus avoids overusing certain routes and achieves load balancing. If multiple routes satisfy the threshold constraint, MTRP selects a route with the smallest hop count to further attain energy efficiency. Based, on MTRP, EMTRP further takes channel condition into consideration and selects routes with better channel condition and consequently reduces the number of retransmissions and saves energy. We analyze the average loss probability (ALP) of the uniform error model and Gilbert error model and give a distributed algorithm to obtain the maximal ALP along a route. Descriptions of MTRP and EMTRP are given in pseudocode form. Simulation results demonstrate that our proposed EMTRP outperforms the representative protocol CMMBCR in terms of total energy consumption and load balancing

Network Utility Maximization in Two-way Flow Scenario

A communication network usually has data packets and acknowledge (ACK) packets being transmitted in opposite directions. ACK packet flows may affect the performance of data packet flows, which is unfortunately not considered in the usual network utility maximization (NUM) model. This paper presents a NUM model in networks with two-way flows (NUMtw) by adding a routing matrix to cover ACK packet flows. The source rates are obtained by solving the dual model and the relation to the routing matrix of ACK packet flows is disclosed. Furthermore, the source rates in networks with one-way flows by the usual NUM model are compared to those in networks with two-way flows by the NUMtw model

A novel method to estimate IP traffic matrix

This letter proposes a novel method to estimate IP traffic matrix (TM). By using the generalized matrix inverse, we are able to overcome the challenge of ill-posed nature of the problem. We describe the inference of TM into an optimization problem and then solve this problem by calculating the {1}- INVERSE of the routing matrix. Numerical results are provided to demonstrate the accuracy of this method

Efficient placement of proxies for hierarchical reliable multicast

The primary focus of this paper is the design of efficient algorithm for the calculation of solution to the placement of proxies for performance optimization in hierarchical reliable multicast (HRM). Proxy is introduced to localize feedback and retransmission, and therefore significantly depress traffic redundancy and reduce latency. Placement of proxies is a key issue in HRM. This paper theoretically analyzes the performance improvement made by placement of proxies and presents a new approach to optimal partition of a subtree for performance optimization in the placement of a single proxy. Based on this approach, we propose a new algorithm, designed in a greedy fashion. We experimentally compare our new algorithm with several existing heuristic algorithms, and observe that it outperforms in the tradeoff between performance and complexity