<title>Design and evaluation of multipoint-to-point multicast flow control</title>

Abstract

Multipoint communication has been an increasingly focused topic in computer communication networks, including both the Internet and the ATM networks. We have previously presented, analyzed, and evaluated new point-tomultipoint ABR flow control algorithms. In this paper, we focus on multipoint-to-point flow control. As the major objective of ABR service is to provide minimum-loss, fair service to data traffic, an effective merge-point scheme for multipoint-to-point flow control should guarantee some suitable fairness. In this paper, we first examine the "essential fairness" concept proposed by Wang and Schwartz for point-to-multipoint flow control in the Internet. We extend and enhance the concept to the multipoint-to-point ABR flow control. A general algorithm guaranteeing essential fairness is presented, with a detailed implementation on top of the ERICA unicast algorithm proposed by Jam, et. al. The general algorithm may be used for a wide range of fairness specifications to accommodate various bandwidth requirement from unicast or multicast sources of different application streams.Three major variations of the general algorithm are presented. These three schemes are simulated and evaluated, and compared with an existing scheme proposed by Ren, Siu, and Suzuki. Simulation results show that the proposed merge-point algorithm achieves, within short transient time, max-mm fairness based on different weights given to individual sources or sessions, or according to various specifications of fairness. The fairness concept and the general algorithm presented here may be readily applied to other high-speed networks such as the Next Generation Internet and Wireless ATM, and to different multicast settings such as point-to-multipoint and multipoint-to-multipoint.

Fair flow control for ATM-ABR multipoint connections

“…Traffic management rules for multipoint-to-point connections are still in their early phases of definition [21,20,2,18]. Ren and Siu [21,20] have described an algorithm for multipoint-to-point congestion control, which assumes that VC merge is employed.…”

“…The algorithm in [2] aims at fairness among the sources as in [21]. The algorithm in [18] adds a weight in RM cells to allow scaling of the rates to give the appropriate allocations to sources. The throughput of a unicast source is given a pre-determined weight with respect to that of a sender in a multicast session.…”

“…Recently more complex algorithms have been developed [2,18] for multipoint-to-point and multipoint-tomultipoint connections respectively. The algorithm in [2] aims at fairness among the sources as in [21].…”

Multipoint-to-point session fairness in the Internet

“…, 6 Moh and Chen [18] also use the concept of weights for each connection, but their definition and algorithm differ from ours. subject to the constraints:…”

“…Fahmy et al [17] give an informal definition for virtual-circuit based (VC-based) fairness, but without a formal definition or an algorithm to achieve the same. Moh and Chen [18] present an informal definition and an algorithm for multipoint-to-point multicast flow control. These approaches benefit from the ability of ATM switches to do complex processing and focus on intra-network merge point behavior.…”