I-TCP: indirect TCP for mobile hosts

IP based solutions to accommodate mobile hosts within existing internetworks do not address the distinctive features of wireless mobile computing. IP-based transport protocols thus suffer from poor performance when a mobile host communicates with a host on the fixed network. This is caused by frequent disruptions in network layer connectivity due to i) mobility and ii) unreliable nature of the wireless link. We describe I-TCP, which is an indirect transport layer protocol for mobile hosts. I-TCP utilizes the resources of Mobility Support Routers (MSRs) to provide transport layer communication between mobile hosts and hosts on the fixed network. With I-TCP, the problems related to mobility and unreliability of wireless link are handled entirely within the wireless link; the TCP/IP software on the fixed hosts is not modified. Using I-TCP on our testbed, the throughput between a fixed host and a mobile host improved substantially in comparison to regular TCP.

[1]  B. R. Badrinath,et al.  Handoff and Systems Support for Indirect TCP/IP , 1995, Symposium on Mobile and Location-Independent Computing.

[2]  Tomasz Imielinski,et al.  Handling mobile clients: a case for indirect interaction , 1993, Proceedings of IEEE 4th Workshop on Workstation Operating Systems. WWOS-III.

[3]  Liviu Iftode,et al.  The effects of mobility on reliable transport protocols , 1994, 14th International Conference on Distributed Computing Systems.

[4]  Van Jacobson,et al.  Compressing TCP/IP Headers for Low-Speed Serial Links , 1990, RFC.

[5]  Samuel J. Leffler,et al.  The design and implementation of the 4.3 BSD Unix operating system , 1991, Addison-Wesley series in computer science.

[6]  Gerald Q. Maguire,et al.  The Design and Implementation of a Mobile Internetworking Architecture , 1993, USENIX Winter.

[7]  W. Timothy Strayer,et al.  XTP as a Transport Protocol for Distributed Parallel Processing , 1994, USENIX High-Speed Networking Symposium.

[8]  Bruce Zenel,et al.  Intelligent communication filtering for limited bandwidth environments , 1995, Proceedings 5th Workshop on Hot Topics in Operating Systems (HotOS-V).

[9]  Mooi Choo Chuah,et al.  Throughput performance of transport-layer protocols over wireless LANs , 1993, Proceedings of GLOBECOM '93. IEEE Global Telecommunications Conference.

[10]  Kimmo E. E. Raatikainen,et al.  Connecting Mobile Workstations to the Internet Over a Digital Cellular Telephone Network , 1994, Mobidata.

[11]  William J. Bolosky,et al.  Mach: A New Kernel Foundation for UNIX Development , 1986, USENIX Summer.

[12]  NagleJohn.  Congestion control in IP/TCP internetworks , 1984 .

[13]  Jerome H. Saltzer,et al.  End-to-end arguments in system design , 1984, TOCS.

[14]  R. Yavatkar,et al.  Improving End-to-End Performance of TCP over Mobile Internetworks , 1994, 1994 First Workshop on Mobile Computing Systems and Applications.

[15]  David J. Farber,et al.  Thinwire protocol for connecting personal computers to the Internet , 1984, RFC.

[16]  Van Jacobson,et al.  TCP Extensions for High Performance , 1992, RFC.

[17]  Armando P. Stettner.  The design and implementation of the 4.3BSD UNIX operating system , 1988 .

[18]  John Nagle,et al.  Congestion control in IP/TCP internetworks , 1984, CCRV.

[19]  Tomasz Imielinski,et al.  Structuring distributed algorithms for mobile hosts , 1994, 14th International Conference on Distributed Computing Systems.

[20]  Jon Postel,et al.  Transmission Control Protocol , 1981, RFC.

[21]  A. Myles.  Comparison of mobile host protocols for IP , 1993 .

[22]  Hiromi Wada,et al.  Mobile Computing Environment Based on Internet Packet Forwarding , 1993, USENIX Winter.

[23]  Dan Duchamp,et al.  Agent-Mediated Message Passing for Constrained Environments , 1993, Symposium on Mobile and Location-Independent Computing.

[24]  Gerald Q. Maguire,et al.  IP-based protocols for mobile internetworking , 1991, SIGCOMM 1991.

[25]  V. Jacobson,et al.  Congestion avoidance and control , 1988, CCRV.