Traffic Management in an ATM Multi-Service Switch for Workgroups

ATM switches have to provide traffic management functions to meet the QoS requirements of different service categories. Among the traffic management functions we will focus on connection admission control (CAC) and priority control in this paper. Besides the mechanisms and algorithms behind these functions the issue of application to a concrete architecture of an ATM multi-service workgroup switch is emphasized. For CAC a new method is proposed that is based on a simple approximation of the effective bandwidth. The difficulties occurring if connections with different parameters are mixed together are solved by handling CBR traffic separately and dividing the parameter space for VBR connections into several regions. Within the VBR regions the linear method is applied while for connections associated to different regions a reduced service rate is considered. The performance of both the priority control mechanisms and the CAC method is evaluated using analysis and simulation

Modelling and evaluation of load and performance control mechanisms of B-ISDN/ATM switching systems

Behandelt wird die Problematik der Last- und Leistungsregelung im Kontext der ATM-basierten Breitband-Vermittlungstechnik.Objective of this thesis are load control and performance control concepts for broadband switching systems. Focus is the services integrating network technology B-ISDN using ATM as transfer mode. The studied mechanisms and concepts are principally of generic nature. Specifically they are designed within the envisaged context of B-ISDN, due to its extensive vision with respect to service integration, Quality of Service (QoS) support and ATM bearer capabilities. Area of application is implicitly the network control plane, but interactions between user and control plane have to be considered, too. The prime scope are switching nodes between access and core network domain, i.e., B-ISDN switches which have to provide user-to-network and network-to-network signalling protocol functions. Thus, beside service distinction call type differentiation is also covered due to the considered network positioning