Interaction of a PON System with a B-ISDN Local Exchange

This chapter covers some of the most critical issues related to the interconnection of the access network (AN) and the local exchange (LEX). The interface between the AN and the LEX is referred to as the Vb interface. A new definition of the Vb interface is given which reflects the B-ISDN/ATM environment and is general enough to cover a wide number of AN types. The novel AN-LEX interface is called the Vbs interface. The VB5 interface structure is described in detail both in terms of supported functions as well as in terms of physical realisation. For the latter an exhaustive list of application choices is given which apply to the employment of the VB5 interface in several cases, with respect to the number of LEXs and STM links.