A VC-Merge Mechanism for QoS Guarantee in IP-Switching Networks

• Main Authors: Chih-Wei Su, 蘇志偉
• Other Authors: Tsang-Ling Sheu
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/73636959068654237468

碩士 === 國立中山大學 === 電機工程學系 === 87 === IP switching technique integrates fast ATM switching and reliable IP routing. In this thesis, we investigate the VC merging problems on IP switching networks. The proposed VC-merge mechanism aims at meeting the original QoS requirements after VC merging. To serve this purpose, we design a VC-merge IP switch and a packet discard mechanism for efficiently managing switch buffers. Two ATM adaptation layers, AAL 3/4 and AAL 5, are compared in encapsulation efficiency as well as their QoS performance. The comparison is performed by a mathematical analysis first, where we investigate the average queueing length, the average queueing delay, and the cell loss ratio under different types of source traffic. Also, we compare the impact of using AAL 3/4 and AAL 5 encapsulation on the transport efficiency. To verify our mathematical results, we build a simulator. In the simulation, we vary the packet length and observe the average queueing delay and length under different source traffic. Finally, based on our comparison results, we conclude this thesis by providing some suggestions in combining VCs to meet QoS requirements under different traffic types.