Management of Reconfigurable Virtual Path Networks

Abstract

We study dynamically rearrangable end-to-end transport networks by means of SDH SONET and or ATM virtual paths. The concept and its advantages are brie y reviewed and we propose a new algorithm for designing such networks. Our algorithm provides integer solutions, handles non-linear equivalent bandwidths, nds its own paths, and allows for an arbitrary design optimisation criterion. It is found to perform equal to or better than an earlier, comparable though more restricted, algorithm. We also put forward a strategy for managing virtual paths in real time. It consists of a repeated cycle of on-line measurement of o ered tra cs followed by the design and implementation of a new virtual path network. Methods and parameters for tra c measurements and network updating frequency are studied and optimised. Applying the strategy to rearrangeable networks subject to variable tra cs in a simulator, we discover considerable gains and a robustness in our parameter settings.

Virtual Path Assignment in ATM Networks

“…Preliminary runs with the Virtual Path Assignment (VPA) Algorithm have been executed for various objective functions and constraints for two sample networks (see figure 3). The 10-node network, and the 23-node network topologies are originally presented in Arvidsson (1994) and Siebenhaar (1994), respectively. For each network, we defined traffic streams with fixed routes between every node pair in both directions ( 90 traffic streams for 10node, and 506 traffic streams for 23-node network).…”

Stochastic allocation of virtual paths to ATM links

“…[1], [2], [3]) to paths of the ATM network graph composed of ATM links with fixed capacity. Below we follow the problem formulation of [4].…”

“…We compare the results of SA with the results obtained by a specialised method described in [9]. The method of [9] is a refinement of the method described in [4], which in tum is an extension (to the VP allocation problem) of the method proposed in [8] for SDH networks. It should perhaps be emphasised that the VP allocation method described in [4] and [9] is not the main goal of these two papers.…”

Enhancing ATM Network Performance by Optimizing the Virtual Network Configuration

“…The problems with full service integration are also realized in [12], and an optimization model taking into account transmission, switching and set up cost is developed in which different strategies like complete partitioning, complete sharing and sharing with trunk reservation can be evaluated. In [1] a greedy algorithm for Dynamic Capacity Management is used to design VP networks and the problem of gathering reliable measurement data is also considered. Concerning multi-rate models, [13] gives an excellent overview.…”