These days, the nature of services and the volume of demand in the
telecommu- nication industry is changing radically, with the replacement
of analog transmis- sion and traditional copper cables by digital
technology and fiber optic transmis- sion equipment. Moreover, we see an
increasing competition among providers of telecommunication services,
and the development of a broad range of new services for users,
combining voice, data, graphics and video. Telecommunication network
planning has thus become an important problem area for developing and
applying optimization models. Telephone companies have initiated
extensive modeling and planning efforts to expand and upgrade their
transmission facilities, which are, for most national telecommunication
networks, divided in three main levels (see Balakrishnan et al. [5]),
namely, l. the long-distance or backbone network that typically connects
city pairs through gateway nodes; 2. the inter-office or switching
center network within each city, that interconnects switching centers in
different subdivisions (clusters of customers) and provides access to
the gateway(s) node(s); 1 2 DESIGN OF SURVNABLE NETWORKS WITH BOUNDED
RINGS 3. the local access network that connects individual subscribers
belonging to a cluster to the corresponding switching center. These
three levels differ in several ways including their design criteria.
Ideally, the design of a telecommunication network should simultaneously
account for these three levels. However, to simplify the planning task,
the overall planning problem is decomposed by considering each level
separately.
