Virtual Path Assignment Research Articles

ATM network design for corporate networks

Asynchronous transfer mode (ATM) networks play an important role in support of distributed applications and modern corporate systems. The applications that use these architectures transfer high volumes of data in high-speed bursts and have stringent delay requirements. To address these needs, network managers seek cost efficient network solutions that provide network capacity sufficient to support high-speed applications. In this paper we present a new formulation and solution procedure for designing ATM networks to support corporate applications. Given the locations of the application servers and multiple clients we would like to design a minimum cost ATM network by which the clients can access the servers. Most of the previous work done in this area separates the problem into a routing problem (virtual circuit routing) and an assignment (virtual path assignment) problem. Thus, the solutions tend to be sub-optimal in the combined problem. This research optimizes virtual path (VP) assignment and virtual circuit (VC) routing simultaneously. We formulate the combined problem explicitly and develop an effective solution method. The solution method provides the designer with virtual paths and virtual circuits over which the actual communication takes place. Computational results are provided.

Architectural design and bandwidth demand analysis for multiparty videoconferencing on SONET/ATM rings

In this paper, we propose a scheme for implementing multiparty videoconferencing service on SONET/ATM rings. We focus on the architectural design and bandwidth demand analysis. Different multicasting methods on SONET/ATM rings are discussed and compared. A new multicast virtual path (VP) called Multidrop which is particularly suitable for SONET/ATM rings is proposed. An add-drop multiplexer (ADM) structure for rings capable of multidropping is also presented. Several VP assignment schemes are proposed and their bandwidth utilizations are compared.

Design and Configuration of Reconfigurable ATM Networks with Unreliable Links

This paper considers a problem of configuring both physical backbone and logical virtual path (VP) networks in a reconfigurable asynchronous transfer mode (ATM) network where links are subject to failures. The objective is to determine jointly the VP assignment, the capacity assignment of physical links and the bandwidth allocation of VPs, and the routing assignment of traffic demand at least cost. The network cost includes backbone link capacity expansion cost and penalty cost for not satisfying the maximum throughput of the traffic due to link failures or insufficient link capacities. The problem is formulated as a zero-one non-linear mixed integer programming problem, for which an effective solution procedure is developed by using a Lagrangean relaxation technique for finding a lower bound and a heuristic method exploited for improving the upper bound of any intermediate solution. The solution procedure is tested for its effectiveness with various numerical examples.

Deterministic algorithm for VP assignment in ATM networks

Virtual Path (VP) assignment is an important resource management activity in ATM networks. By using the VP concept, the logical layout of the network can be administered to minimize the total network cost to the provider. We formulate the VP assignment problem as a constrained optimization problem; the objective function to be minimized reflects processing/control costs at nodes and transmission costs between nodes. The blocking probability quality of service (QoS) requirements and overall throughput of the network are taken into consideration in the solution process as constraints. Since the solution space is complex, we develop a deterministic, iterative heuristic algorithm to reach a ‘near-optimal’ VP configuration for a given physical network and traffic demand. The Multi-Rate Loss Network model is used in the calculation of connection-level blocking probabilities. Results for static connection-routing are presented, for various forms of the objective function and constraints.