08.023GPPBase Station System - Mobile Services Switching Centre (BSS-MSC) Interface - Interface PrinciplesRelease 1999TS
The transcoder will be functionally integrated into the BSS. It is not considered to be a stand alone piece of equipment. The control of the transcoder will therefore take place directly via the BSS, an explicit control interface between BSS and transcoder will not be defined.
Dependent on the relative costs of transmission plant for a particular administration, there is an economic benefit, for larger cells and certain network topologies, in having the transcoder positioned at the MSC site. However, for smaller cells there may actually be a cost penalty due to special multiplexing.
When the transcoder is geographically sited at the MSC site, it shall still be considered part of the BSS, and as such is on the BSS side of the BSS-MSC interface.