Fairness for ABR multipoint-to-point connections

TL;DR

This paper explores fairness definitions and allocation algorithms for ATM multipoint-to-point connections, addressing the challenges of multiple senders and the need for adapted bandwidth sharing strategies.

Contribution

It introduces various fairness definitions for multipoint connections and highlights the necessity of adapting ATM bandwidth algorithms for fairness.

Findings

Different fairness models for multipoint connections are proposed.

Existing algorithms need modifications to ensure fairness in multipoint scenarios.

Tradeoffs between fairness and implementation complexity are discussed.

Abstract

In multipoint-to-point connections, the traffic at the root (destination) is the combination of all traffic originating at the leaves. A crucial concern in the case of multiple senders is how to define fairness within a multicast group and among groups and point-to-point connections. Fairness definition can be complicated since the multipoint connection can have the same identifier (VPI/VCI) on each link, and senders might not be distinguishable in this case. Many rate allocation algorithms implicitly assume that there is only one sender in each VC, which does not hold for multipoint-to-point cases. We give various possibilities for defining fairness for multipoint connections, and show the tradeoffs involved. In addition, we show that ATM bandwidth allocation algorithms need to be adapted to give fair allocations for multipoint-to-point connections.