Performance Evaluation of an Internet Protocol Security (IPSec) Based Multiprotocol Label Switching (MPLS) Virtual Private Network

This paper evaluates the performance of Internet Protocol Security (IPSec) based Multiprotocol Label Switching (MPLS) virtual private network (VPN) in a small to medium sized organization. The demand for security in data networks has been increasing owing to the high cyber attacks and potential risks associated with networks spread over distant geographical locations. The MPLS networks ride on the public network backbone that is porous and highly susceptible to attacks and so the need for reliable security mechanisms to be part of the deployment plan. The evaluation criteria concentrated on Voice over Internet Protocol (VoIP) and Video conferencing with keen interest in jitter, end to end delivery and general data flow. This study used both structured questionnaire and observation methods. The structured questionnaire was administered to a group of 70 VPN users in a company. This provided the study with precise responses. The observation method was used in data simulations using OPNET Version 14.5 Simulation software. The results show that the IPSec features increase the size of data packets by approximately 9.98% translating into approximately 90.02% effectiveness. The tests showed that the performance metrics are all well within the recommended standards. The IPSec Based MPLS Virtual private network is more stable and secure than one without IPSec.

Down to Zero Size of VoIP Packet Payload

Voice over Internet Protocol(VoIP)is widely used by companies,schools,universities,and other institutions.However,VoIP faces many issues that slow down its propagation.An important issue is poor utilization of the VoIP service network bandwidth,which results from the large header of the VoIP packet.The objective of this study is to handle this poor utilization of the network bandwidth.Therefore,this study proposes a novel method to address this large header overhead problem.The proposed method is called zero size payload(ZSP),which aims to reemploy and use the header information(fields)of the VoIP packet that is dispensable to the VoIP service,particularly the unicast IP voice calls.In general,these fields are used to carry the VoIP packet payload.Therefore,the size of the payload is reduced to save bandwidth.The performance estimation results of the proposed ZSP method showed a considerable improvement in the bandwidth utilization of the VoIP service.For example,the saved bandwidth in the tested scenario with the G.723.1,G.729,and LPC codecs reached 32%,28%,and 26%respectively.

An efficient QoS enhancement mechanism of VoIP using erasure array codes

In order to solve the problem of losing voice packets in voice over internet protocol(VoIP),a kind of lost packets double recovery algorithm is proposed. The algorithm is based on erasure coding technique which comes from highly available data storage systems. An efficient coding scheme with higher tolerance based on STAR and Reed-Solomon( RS) erasure code is described. An efficient method is also provided which could transform the voice data packets of one dimensional bit stream into two dimensional array according to given window size. If the lost rate has increased beyond the error correction capability,packet-loss concealment will be adopted. Under various conditions of packet-loss simulation during the experiments,the algorithm has proved its better performance on MOS rating and coding rate.