Patent ID: 8644349
Filing Date: 2014-02-04
Classification: H04J

Abstract:
1. A method of clock recovery in a network comprising an ingress TDM network segment and an egress TDM network segment which are connected by a packet-switched network, an ingress inter-working function at an interface between the ingress TDM network segment and the packet-switched network and an egress inter-working function at an interface between the packet-switched network and the egress TDM network segment, the method comprising, at the ingress inter-working function: receiving a TDM traffic flow comprising TDM data which is clocked by an ingress data clock; performing a first mapping function which maps the TDM data into first data containers using an ingress reference clock, wherein the first mapping function conveys a difference between the ingress data clock and the ingress reference clock which can be recovered by the egress inter-working function, the difference being conveyed by a rate of justification operations to the mapped data within the first data containers; performing a packetising function which maps the first data containers into payloads of packets; and, transmitting the packets onto the packet-switched network.