NETWORKING 2005. Networking Technologies, Services, and Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communications Systems

Volume 3462 of the series Lecture Notes in Computer Science pp 780-791

End-to-End Asymmetric Link Capacity Estimation

  • Ling-Jyh ChenAffiliated withComputer Science Department, UCLA
  • , Tony SunAffiliated withComputer Science Department, UCLA
  • , Guang YangAffiliated withComputer Science Department, UCLA
  • , M. Y. SanadidiAffiliated withComputer Science Department, UCLA
  • , Mario GerlaAffiliated withComputer Science Department, UCLA


Knowledge of link capacity is important for network design, management, and utilization. With the increasing popularity of asymmetric link technologies (such as DSL, 1xRTT, and satellite links), it is desirable to have a capacity estimation technique, which can simultaneously measure forward and backward direction link capacities on an Internet path. Moreover, this estimation must often be “sender only”, because of receiver limitations or lack of standards. In this study, we propose a simple, fast and accurate technique, called AsymProbe, to estimate asymmetric link capacities. AsymProbe is a “sender only”, round trip procedure. It achieves asymmetric link capacity estimation by strategically altering the ratio of probe and acknowledgement packet sizes. Using simulation and testbed experiments, we validate AsymProbe with a variety of network configurations. The results show that AsymProbe can correctly estimate the asymmetric link capacities as long as an appropriate packet size ratio can be employed.