Digital Data Service (DDS) is widely used for providing private high quality digital transport service in the telecommunications industry. The network connections of DSS are permanent and its transmission facilities are dedicated, enabling it to transfer digital data with less interference and greater security than switched service. DSS also proves to be appropriate for linking sites that have applications which require a permanent connection and a demonstrated need for frequent data transfer. | Telecommunications Optimization Heuristic and Adaptive Techniques. Edited by David W. Corne Martin J. Oates George D. Smith Copyright 2000 John Wiley Sons Ltd ISBNs 0-471-98855-3 Hardback 0-470-84163X Electronic 4 Tabu Search and Evolutionary Scatter Search for Tree-Star Network Problems with Applications to Leased-Line Network Design Jiefeng Xu Steve Y. Chiu and Fred Glover Introduction Digital Data Service DDS is widely used for providing private high quality digital transport service in the telecommunications industry. The network connections of DSS are permanent and its transmission facilities are dedicated enabling it to transfer digital data with less interference and greater security than switched service. DSS also proves to be appropriate for linking sites that have applications which require a permanent connection and a demonstrated need for frequent data transfer. For example it can be used for remote Local Area Network LAN access entry into frame relay networks support for transactionbased systems and can be incorporated in IBM s System Network Architecture SNA and other networks. With optimal DSS network design and sufficient use DSS becomes economically competitive with frame relay service in the higher transmission speed ranges and with analog private line service in the lower transmission speed ranges. Telecommunications Optimization Heuristic and Adaptive Techniques edited by D. Corne . Oates and . Smith 2000 John Wiley Sons Ltd 58 Telecommunications Optimization Heuristic and Adaptive Techniques In this chapter we address a fundamental DDS network design problem that arises in practical applications of a telecommunications company in the United States. The decision elements of the problem consist of a finite set of inter-offices hubs and a finite set of customer locations that are geographically distributed on a plane. A subset of hubs are chosen to be active subject to the restriction of forming a network in which every two active hubs .
