1st Annual Conference on Broadband Networks

Research Article

Decoupling packet loss from blocking in proactive reservation-based switching

  • @INPROCEEDINGS{10.1109/BROADNETS.2004.28,
        author={Mahmoud Elhaddad and Rami Melhem and Taieb Znati},
        title={Decoupling packet loss from blocking in proactive reservation-based switching},
        proceedings={1st Annual Conference on Broadband Networks},
  • Mahmoud Elhaddad
    Rami Melhem
    Taieb Znati
    Year: 2004
    Decoupling packet loss from blocking in proactive reservation-based switching
    DOI: 10.1109/BROADNETS.2004.28
Mahmoud Elhaddad1,*, Rami Melhem1,*, Taieb Znati1,*
  • 1: Department o f Computer Science, University of Pittsburgh, Pittsburgh, PA 15260
*Contact email: elhaddad@cs.pitt.edu, melhem@cs.pitt.edu, znati@cs.pitt.edu


We consider the maximization of network throughput in buffer-constrained optical networks using aggregate bandwidth allocation and reservation-based transmission control. Assuming that all flows are subject to loss-based TCP congestion control, we quantify the effects of buffer capacity constraints on bandwidth utilization efficiency through contention-induced packet loss. The analysis shows that the ability of TCP flows to efficiently utilize successful reservations is highly sensitive to the available buffer capacity. Maximizing the bandwidth utilization efficiency under buffer capacity constraints thus requires decoupling packet loss from contention-induced blocking of transmission requests. We describe a confirmed (two-way) reservation scheme that eliminates contention-induced loss, so that no packets are dropped at the network's core, and loss can be incurred only at the adequately buffer-provisioned ingress routers, where it is exclusively congestion-induced. For the confirmed signaling scheme, analytical and simulation results indicate that TCP aggregates are able to efficiently utilize the successful reservations independently of buffer constraints.