US Patent 8155520 Multi-fabric shelf for a transport network

A network element of a transport network has three fabrics housed within a single shelf of a telco rack, namely a packet fabric, an electrical fabric and an optical fabric. The shelf also includes inter-fabric circuitry, to bridge between the fabrics, e.g. packet-electrical and/or electrical-optical and/or packet-optical. The inter-fabric circuitries switchably transmit packets across fabrics in intermediate nodes of the transport network. The single shelf of some embodiments has a wall (“midplane”) between a rear region that holds the three fabrics and a front region that holds inter-fabric circuitry, and external interfaces to optical trunks and/or packet services and/or optical tributaries.