Thomas Meuser

A Software Architecture for Control and Management of Distributed ATM Switching

Distributed switching will become a key feature for flexible and inexpensive workgroup switches as well as for dedicated high performance networking solutions. The Philips Research Laboratories in Aachen have demonstrated the feasibility of distributed ATM switching by developing a ring-based ATM switch. After solving the hardware related problems we are now focusing our efforts on the design of a distributed software platform for switch control and management purposes.

Open Switching for ATM Networks

This contribution discusses the way how Open Switching can be supported in ATM networks. First the elements of an ATM system that are relevant for call control and call handling are described. Then we evaluate which of the call control interfaces should be realized by which parts of the system, especially which signalling aspects are relevant for the software architecture on network side. Finally we propose a concept for the integration of external call control as part of the network control architecture. The paper aims at a switch control architecture that facilitates for providing advanced applications in ATM networks by external call control. The definition of standardized protocols and the design of Open Switching applications themselves are out of the scope of our work.

Management Architecture for ATM Over ADSL-Based Access Networks

ADSL (Asymmetric Digital Subscriber Line) is a new key technology for offering broadband services to home users and small businesses. ADSL technology is ready to take off. Management discussions aim at achieving an ADSL broadband service architecture are still taking place, however. In order to support multiple services over widely spread networks incorporating various transmission techniques, a cost-effective network operation requires an end-to-end network management architecture. We describe here how to integrate ADSL equipment into the existing telecommunications management network. Alternative protocols and information models are also discussed. The overall network management architecture gives the motivation for the management concept applied to our Digital Subscriber Line Access Multiplexer (DSLAM). The design of such a network element covers all management functionality that is required to multiplex ATM connections being transferred over the ADSL system and to integrate the network element into any telecommunications network. We have chosen a flexible approach to adapt the DSLAM management to different usage environments.

Distributed ATM switching topologies in tree-structured networks

HFC networks, today mostly used to broadcast traditional cable TV programs, will possibly play a major role in future broadband access network development. The structure of HFC networks is briefly described and bottlenecks in case of high load are identified. To improve performance and eliminate the bottleneck, the approach presented in this paper suggests the replacement of passive network elements like fiber nodes and signal amplifiers by ATM switches. This approach has been evaluated with respect to various network topologies and user scenarios. A simulation model used for the evaluation is presented within this paper and simulation results are discussed.