Dynamic Rerouting of Guaranteed Quality-of-Service Connections [Vol. 4, No. 2, 1996]

Dynamic Rerouting of Guaranteed Quality-of-Service Connections

Collin Parris
IBM
T.J.Watson Research Center
Yorktown Heights, New York
Email: cjparris_AT_watson.ibm.com

Hui Zhang
School of Computer Science
Carnegie Mellon University
Email: hzhang_AT_cs.cmu.edu

Abstract
To support the widespread demands for integrated services various solutions have been proposed to provide guaranteed Quality-of-Service (QoS) services in packet-switched networks. These solutions usually require fixed route selection and resource reservation on a per connection basis. The routing and reservation decisions, combined with load fluctuations, introduce the problems of network unavailability and loss of network management flexibility. We believe that these problems can be alleviated by transparently rerouting connections to properly balance the network load. In this paper, we present a solution that supports transparent route modification of guaranteed QoS connections during the life time of the connections. As the emphasis of this work is to support transparency we must ensure that during and after the rerouting, the QoS guarantees made to the client are preserved, and the interface instances at both the sender and receiver are unaltered. Our solution includes the mechanisms that support the transparent rerouting of connections, and a routing algorithm that is based on the traffic characteristics, the delay, and the jitter requirements of a connection. This routing algorithm can also use various administrative constraints and facilitate the reuse of resources currently reserved by the connection. To optimize the solution, additional mechanisms have been introduced to reduce the time needed to reroute a connection and to support rerouting of segments of a connection. The solution has been implemented in the context of the Tenet scheme and route changes can be observed and controlled by using the Simple Network Management Protocol (SNMPv1). Simulation experiments and some initial measurement of the implementation demonstrate that such a scheme is useful, practical, and can be achieved with load overhead.

Keywords: Transparent rerouting; guaranteed QoS; resource sharing; intelligent restart.

JNSM: Vol. 4, No. 2, 1996 Dynamic Rerouting of Guaranteed Quality-of-Service Connections [Vol. 4, No. 2, 1996]

NOTE: only abstract of paper available on-line

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