Abstract: An improved spanning tree protocol for use by token ring intermediate devices having one or more Concentrator Relay Function (CRF) entities and associated Bridge Relay Function (BRF) entities. Each CRF and BRF entity preferably includes a spanning tree engine and corresponding database for individually executing an instance of the spanning tree algorithm and is configured to select a different Bridge Protocol Data Unit (BPDU) message type for use in executing its respective spanning tree algorithm. The selection of BPDU message type by the CRF and BRF spanning tree engines preferably depends on the routing configuration of the associated CRF. The selection of BPDU message type by the CRF entities assures that they are dropped by legacy intermediate devices and only acted upon by the originating CRF or another CRF coupled thereto.

Abstract: An N:1 transcoder (12, 40) with a compression data path that includes uncompressed digroup circuits (92, 94, 96, 98, and 100) each receiving N incoming uncompressed signal and extracting a plurality of control, signaling, and voice/data traffic channels therefrom, a compressor (120) coupled to the uncompressed digroup circuits (92, 94, 96, 98, and 100) and compressing data in selected ones of the extracted voice/data channels, and a compressed data circuit (126) coupled to the compressor (120) for packing the compressed data into predetermined channels of one compressed signal, and further providing control, signaling, and performance monitoring information embedded therein.