Optimization and Systems Theory Seminar
Friday, June 13, 1997, 11.00-12.00, Room 3721, Lindstedtsvägen 25

Michal Pióro
Department of Communication Systems
Lund Institute of Technology
E-mail: Michal.Pioro@tts.lth.se

Robust design problems in telecommunication networks

The issue of robustness is profound in today's telecommunication network design as the network operators, especially in competitive markets, seek to satisfy the constant growth of the customers' demand for service quality and continuity in all failure/traffic situations. Modern switching and signalling systems installed in the digital exchanges, ATM switches and SDH/ SONET cross-connects provide powerful capacity restoration means, which, combined with proper design algorithms, can secure network robustness in an economical way.

The purpose of the seminar is two-fold. Firstly, a set of general (generic) design tasks will be formulated, whose instances are applicable to any layer of the network resources, such as the SDH transmission layer, ATM virtual path layer and IDN/ATM routing layer. Due to their generic nature, the tasks can also simplify the use of iterative design schemes for simultaneous design of a number of resource layers, leading to an economically dimensioned network, robust to link and node failures, and to traffic pattern variations. The generic tasks formulation aims to generalise the instances of the robust design problems discussed in the literature.

The considered optimisation tasks belong to the class of uncapacitated multicommodity integral flow problems, and as such are in general NP-complete. The second purpose of the seminar is to present a stochastic discrete optimisation method, called Simulated Allocation (SA), which can be used as a general approach for solving the tasks. The effectiveness of SA will compared with other methods, and on this basis it will be suggested that SA can serve as a practical engineering method, producing good suboptimal solutions with a fair programming and computational effort.

Calendar of seminars
Last update: June 3, 1997 by Anders Forsgren, andersf@math.kth.se.