Explicit Rate-based Flow Control in MANET

Flow control in mobile ad hoc network (MANET) must face many new challenges such as frequent re-routing and bandwidth variation of the wireless links. TCP’s implicit AIMD flow control performs poorly in this environment, because it often cannot keep up with the dynamics of the network.

In this project, we explore the potential utility of explicit flow control in the MANET domain. To this end, we propose an end-to-end rate-based flow control scheme (called EXACT), where a flow’s allowed rate is explicitly conveyed from intermediate routers to the end-hosts in each data packet’s special control header. Each router computes the data rates for the flows currently passing through the router, and modifies the header of each packet to reflect the flow’s allowed sending rate. As a result, EXACT reacts quickly and precisely to re-routing and bandwidth variation, which makes it especially suitable for a dynamic MANET network. By ns-2 simulations, we show that EXACT outperforms TCP in terms of fairness and efficiency, especially in a highly dynamic MANET environment.


  • Kai Chen, Klara Nahrstedt, Nitin Vaidya, The Utility of Explicit Rate-Based Flow Control in Mobile Ad Hoc Networks, IEEE Wireless Communications and Networking Conference (WCNC 2004), Atlanta, Georgia, USA, March 2004.
  • Kai Chen, Klara Nahrstedt, EXACT: An Explicit Rate-based Flow Control Framework in MANET (extended version), Technical Report UIUCDCS-R-2002-2286/UILU-ENG-2002-1730, Department of Computer Science, University of Illinois at Urbana-Champaign, July, 2002.