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| Ethernet IP video distribution Zarlink Semiconductor 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 ZL 33042 with 24 FE (Fast Ethernet) + 2 GE (Gigabit Ethernet) port configurations and the ZL33046 Ethernet switch delivering 16 FE + 2 GE port configurations. Future devices will incorporate lower and higher data throughput and optional port count configurations. 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. The architecture supports per-flow two-rate, three-color metering and policing. Scheduling algorithms, such as SP (strict priority) and WFQ (weighted fair queuing), manage packets and prioritize queued traffic. Hardware-based security features 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. The ClassSwitch family's built-in "packet identifier" micro-engine pre-filters L2 to L7 packet fields can be used to match suspicious traffic types. If user programmable patterns are recognized, the devices forward suspicious packets to off-the-shelf Deep Content Analysis processors for further analysis. Zarlink classifier switches can be programmed to accept or deny service based on the information used for classification. Programmable prioritized filtering and forwarding allows hardware-based per-flow accounting, allowing processor resources to be dedicated to more important tasks. The ToS (type of service), priority or DSCP (differentiated service code points) bits can be re-tagged based on the traffic classification allowing DiffServ implementations at wire-speed. New service level agreements based on Ethernet type, VLAN ID, 802.1p priority Type of Service (ToS, DSCP), L2/L3 and subnet addresses, L4 port numbers and others are immediately possible at wire-speed. write your comments about the article :: © 2006 Networking News :: home page |