TDM operates over PSN without headaches
By Nicholas Cravotta -- EDN, July 8, 2004
Zarlink Semiconductor’s new ZL50111 family of TDM (time-division-multiplexing)-over-IP (Internet Protocol) packet processors meets the protocol requirements in the recently announced ITU-T (International Telecommunications Union Telecommunications) TDM-MPLS (Multiprotocol Label Switching) networking spec. The specification, called User Plane Interworking, Recommendation Y.1413, outlines the TDM timing, signaling, service quality, and alarm integrity necessary to carry legacy voice, data, and multimedia traffic over an MPLS network at up to DS3 or E3 rates.
Service providers hoping to consolidate networks and reduce operating costs can use MPLS switches to carry network traffic, such as voice-over-packet, over a converged PSN (packet-switched network) and still cost-effectively transport TDM-based traffic with guaranteed quality of service.
The ZL50111 family complies with both the structure-aware and structure-agnostic modes of operation that the recommendation outlines and uses CESOP (circuit-emulation-services-over-packet) technology to tunnel many forms of Layer 2 TDM traffic over the PSN. The TDM-over-IP packet processors maintain critical timing and service-quality requirements by guaranteeing submillisecond latency through the devices with accurate clock recovery and synchronization. On-chip queuing mechanisms minimize the effect of network latency by prioritizing time-sensitive TDM packets over data packets in processing queues. Currently in production, the ZL50111 sells for $276.47 (1000).
Zarlink Semiconductor, 1-613-592-0200, www.zarlink.com.
