Ethernet Switch-On-A-Chip Targets The IP DSLAM Market

Telecom carriers now use DSL to implement triple-play (voice, video, and data) services. SwitchCore AB's Xpeedium2Pro switch-on-a-chip IC family should help OEMs develop cost-effective equipment that will let carriers tap into these emerging triple-play services. These chips exploit the cost advantages of Ethernet while offering the same carrier-class reliability as legacy ATM equipment.

The CXE 2139 is a 28-port Gigabit Ethernet (GbE) device that provides a complete layer 2 and layer 3 switch/router solution, including forwarding and classification (see the figure). The CXE 2039 is a 28-port switch that has all of the functionality of the CXE 2139 but without the layer 3 forwarding. And, the CXE 1109 has 24 ports of Fast Ethernet (100 Mbits/s) plus four ports of GbE in a switch/router that has all the functionality of the CXE 2139, making it ideal for mini-DSLAM applications.

Each of these devices supports up to 4000 subscribers with three separate SLA-enforced (service level agreement) service levels per subscriber for voice, video, and data. The chips also collect subscriber statistics to facilitate SLA billing.

These chips provide flexibility for video local-area network (LAN) forwarding and swapping, making it simple to implement a drop-in replacement for existing ATM-based DSLAMs by emulating the ATM-style virtual circuit concept. The chip architecture prevents head-of-line blocking, ensuring that high-priority traffic is never interrupted by queued-up lower-priority traffic. For example, a Voice over Internet Protocol call would receive priority over a file download operation.

Available now, the Xpeedium2Pro chips cost $260 each in 10,000-unit quantities. SwitchCore also offers a software development kit and a complete reference design.