ClassSwitch single-chip full-service Layer 2 Ethernet switches are designed for network access equipment supporting packet-based applications, such as IPTV.
Zarlink Semiconductor has introduced the first two devices in its new ClassSwitch platform of single-chip, full-service Layer 2 Ethernet switches designed for network access equipment supporting packet-based applications, such as IPTV (Internet Protocol television). Zarlink’s ClassSwitch platform supports the cost-effective design of line cards or compact systems deployed in central offices, cable head-ends or customer premises equipment that must aggregate, inspect and modify multiple real-time applications delivered over Fast and Gigabit Ethernet. The devices enable IP multicast packet-forwarding service distribution, a key element in the delivery of IP video in the first mile.

The platform includes the ZL33042 with 24 Fast Ethernet and two gigabit Ethernet port configurations and the ZL33046 Ethernet switch delivering 16 Fast and two Gigabit ports.

Future devices will incorporate lower and higher data throughput and optional port count configurations.

Growing demand for real-time packet services, including television over broadband, requires network access equipment that more efficiently analyses and manages network traffic.

Pacific Crest estimates the IPTV market will grow from 3 million subscribers today to over 25 million in 2008, and 75 million in 2010.

As IP applications and web-based services dominate network traffic, access equipment must be able to efficiently identify and handle an increasing number of IP-based ‘user packet flow’ types.

For example, IPTV, VoIP, video-on-demand, and control and signalling messages are distinct flows that must be uniquely managed.

Zarlink’s ClassSwitch platform provides high intelligence for aggregation equipment, while lowering equipment design costs by integrating multiple features on a single chip.

Packets entering the devices are classified to a flow based on user-defined rules, using information such as frame source and destination address or applications using L2 (Layer 2) to L7 (Layer 7) fields of incoming packets.

Up to 1024 distinct flows can be created per device.

The architecture supports per-flow two-rate, three-colour metering and policing.

Scheduling algorithms, such as SP (strict priority) and WFQ (weighted fair queuing), manage packets and prioritise queued traffic.

Zarlink’s Ethernet switches integrate a hardware-based DOS (denial of service) attack-flow engine to protect against viruses and malicious attacks.

This attack prevention engine ensures uninterrupted services while preventing the loss of information or revenue that can result from network disruptions.

Zarlink’s Ethernet switches include up to 24 MACs (media access controllers) for 10/100Mbit/s and two GMACs (gigabit MACs) for 10/100/1000Mbit/s.

All MACs and GMACs support copper (twisted wire) or fibre physical interfaces.

In its core, the device family provides multi-field traffic classification of L2 and L7 fields, IP Multicast and Unicast bandwidth distribution, and a traffic queuing engine.

Fair management of traffic is maintained at all times through an advanced WFQ scheduling algorithm, flexible packet buffer and queue management, and a WRED (weighted random early detect) algorithm.

To simplify equipment design, the platform’s parametric programmability allows efficient and flexible system development without requiring additional programming for network processor implementations.

Programmable prioritised filtering and forwarding allows hardware-based per-flow accounting, allowing processor resources to be dedicated to more important tasks.

Zarlink’s ClassSwitch family is supported by a field-proven software platform.

The switches incorporate device driver software offering an easy-to-use API supporting advanced access control, and various protocol modules including IGMPv3 for IP video applications.

The ZL33042 and ZL33046 Ethernet switches, available now.

Evaluation boards with various plug-in modules for 100/1000 Ethernet transceivers as well as CPUs based on PowerPC, ARM and MIPS will be available soon.