Mobile Networks and Applications

, Volume 5, Issue 1, pp 57–71 | Cite as

Improving TCP performance over wireless networks at the link layer

  • Christina Parsa
  • J.J. Garcia‐Luna‐Aceves


We present the transport unaware link improvement protocol (TULIP), which dramatically improves the performance of TCP over lossy wireless links, without competing with or modifying the transport- or network-layer protocols. TULIP is tailored for the half-duplex radio links available with today's commercial radios and provides a MAC acceleration feature applicable to collision-avoidance MAC protocols (e.g., IEEE 802.11) to improve throughput. TULIP's timers rely on a maximum propagation delay over the link, rather than performing a round-trip time estimate of the channel delay. The protocol does not require a base station and keeps no TCP state. TULIP is exceptionally robust when bit error rates are high; it maintains high goodput, i.e., only those packets which are in fact dropped on the wireless link are retransmitted and then only when necessary. The performance of TULIP is compared against the performance of the Snoop protocol (a TCP-aware approach) and TCP without link-level retransmission support. The results of simulation experiments using the actual code of the Snoop protocol show that TULIP achieves higher throughput, lower packet delay, and smaller delay variance.


Medium Access Control Data Packet Wireless Link Medium Access Control Protocol Packet Delay 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Christina Parsa
    • 1
  • J.J. Garcia‐Luna‐Aceves
    • 1
  1. 1.Computer Engineering Department, Baskin School of EngineeringUniversity of CaliforniaSanta CruzUSA

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