Impact of layer two ARQ on TCP performance in W-CDMA networks

We address the interaction between TCP and RLC (Radio Link Control), the link layer retransmission protocol in W-CDMA, a 3rd generation cellular wireless network technology, in evaluating TCP performance in following points; l) Supress delay-jitter in link layer to avoid excess retransmissions. 2) Clarify the trade-off between jitter-suppression and link utilization to improve TCP throughput. 3) Optimize the link layer and TCP parameters. We show how to find the TCP and link ARQ parameters that yield optimum overall performance; simulations and emulation confirm their effectiveness. The coexistence of ARQ and TCP can lead to inefficient interaction; the delay-jitter on the link layer may trigger spurious TCP retransmission. The solution is to suppress jitter on the link layer. To manage the trade-off between this suppression and link utilization, we optimized with link parameter.

[1]  Mehmet Yavuz,et al.  Running TCP over IS-2000 , 2002, 2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333).

[2]  Hiroshi Inamura,et al.  TCP over Second (2.5G) and Third (3G) Generation Wireless Networks , 2003, RFC.

[3]  T. Chahed,et al.  End-to-end reliability in UMTS: TCP over ARQ , 2001, GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270).

[4]  J. C. Stekas Meeting demands of mobile Internet applications , 2001, Proceedings 2001 Symposium on Applications and the Internet Workshops (Cat. No.01PR0945).

[5]  Randy H. Katz,et al.  The Eifel algorithm: making TCP robust against spurious retransmissions , 2000, CCRV.

[6]  Vern Paxson,et al.  Computing TCP's Retransmission Timer , 2000, RFC.

[7]  Nitin H. Vaidya,et al.  Long Thin Networks , 2000, RFC.

[8]  Sally Floyd,et al.  TCP Selective Acknowledgement Options , 1996 .

[9]  B. R. Badrinath,et al.  I-TCP: indirect TCP for mobile hosts , 1995, Proceedings of 15th International Conference on Distributed Computing Systems.

[10]  Randy H. Katz,et al.  The effects of asymmetry on TCP performance , 1999, Mob. Networks Appl..

[11]  Sally Floyd,et al.  TCP Selective Acknowledgment Options , 1996, RFC.

[12]  Gorry Fairhurst,et al.  Advice for Internet Subnetwork Designers , 2004, RFC.

[13]  Srinivasan Seshan,et al.  Improving TCP/IP performance over wireless networks , 1995, MobiCom '95.

[14]  Keith Sklower,et al.  The Eifel retransmission timer , 2000, CCRV.

[15]  Antti Toskala,et al.  Wcdma for Umts , 2002 .

[16]  Mark Allman,et al.  On the generation and use of TCP acknowledgments , 1998, CCRV.

[17]  Gang Wu,et al.  Interactions of TCP and radio link ARQ protocol , 1999, Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324).