SCOOP has been developed to postprocess data collected on telephone exchanges. The authors examine the load and traffic observation results related to local or combined local-toll central offices. They explain how the measurements for several exchanges forming a local network can be integrated to generate a point-to-point traffic matrix. The software package is briefly described.>

This paper describes a local network evolution model for digital switching introduction and the associated algorithm used to determine a feasible optimal network evolution policy. Such a policy is defined by the type, location, and time of placement of digital switches and remote concentrators as well as the homing pattern, i.e., the assignment of concentrators to digital switches. In addition, the evolution policy is characterized by the mode in which the digital switch or remote concentrator is used. Two modes are considered here: 1) overlay where analog equipment is retained at a switching center, growth as well as potentially removed analog lines being served by digital eqmpment; and 2) replacement where analog switches are replaced by digital equipment. The basic cash flows considered in the economic analysis correspond to switching, trunking, and interface costs. Optimality is understood here in terms of minimizing an economic criterion such as the present worth of annual Charges (PWAC) or net present value (NPV). Results obtained using the optimization algorithm in conjunction with a real local telephone exchange network are also presented.

This paper considers a problem of telecommunications network modernization. The model presented provides the cost criterion corresponding to a general network evolution strategy which may consist of a combination of three basic policies: expansion of existing facilities; overlay of existing facilities with modern equipment to serve the growth; or replacement of existing facilities with modern equipment. The cost criterion is basically defined as the cumulated sum of all inflated discounted cash flows. Two major problems are discussed: 1) the single location or local facility evolution problem applicable to single transmission links or switching nodes and 2) the multilocation problem involving several nodes. An application of the second problem described here concerns the selection of switching equipment types for a telephony network (including remote concentrators). For both problems, simple necessary and sufficient conditions are derived for pure strategies to be optimal. Pure strategies involve events occurring at the beginning and/or end of the study horizon.

The availability of digital switching equipment has created a new perspective in network planning, especially with the introduction of digital switching into the existing local telephone network. A model is described as well as results derived using real network data. The model defines feasible network evolution strategies and the corresponding economic criterion. The results include the derivation and evaluation of a selected set of local network strategies and various sensitivity and cost analyses which investigate several network architectures and digital introductory techniques.

This paper considers the problem of the optimal introduction of digital switching equipment into an existing analog local telephone network. The criterion used is the present worth of annual charges. Using certain plausible assumptions, this multilocation dynamic problem is shown to reduce to an equivalent static problem. The latter can be expressed as a classical plant location problem for which several solution techniques are available in the operations research literature.