Exploitation of synchronous digital hierarchy features to provide multidestination satellite communications

The paper addresses the role that the synchronous digital hierarchy (SDH) can play in providing effective multi-destination satellite communications. SDH and its earlier partner SONET are generally considered to be appropriate to the optical fibre cable transmission domain. It shows their applicability to satellite systems and how they are well matched to that transmission media. In particular it is indicated how SDH can be exploited for multi-destination operation. Several important areas need to be addressed in order to make such a system viable and these are discussed. These are: the need for Sub-STM-1 transmission over the satellite path; provision of management information flow in a multi-destination system; and engineering service circuit requirements; potential additions to the SDH specification. The implementation of such an approach compared to other PSTN satellite access approaches is also discussed.