Lucent takes direct aim at Cisco, Ascend with giant IP switch

By David Rohde
Network World Fusion, 5/28/98

Lucent Technologies, Inc. yesterday proved as good as its word - it's going to compete tooth and nail with top data vendors to provide giant IP switching capacity.

The telecom equipment giant unveiled the PacketStar IP Switch, a carrier-class Layer 3/Layer 4 routing switch that potentially provides thousands of different levels of service quality for IP applications.

The PacketStar switch delivers up to 32 million packet/sec with 128G bit/sec of total backplane capacity. It initially will be sold to carriers and ISPs that are also being targeted by Cisco Systems, Inc. with its 12000 Gigabit Switch Router, unveiled about a year ago.

Bill O'Shea, president of Lucent's Data Networking Division, said that new Bell Laboratories-developed algorithms enable the PacketStar switch to support up to 64,000 separate traffic queues. As a result, carriers who install the switch in their networks could assign numerous service levels - everything from "virtual leased lines" with nearly guaranteed continuous throughput down to pure best-effort service - to different queues and standardize them as service offerings to customers.

The key to Lucent's approach is that by going to Layer 4, the switch will examine each packet for the TCP protocol as well as the IP header. As a result, it will base traffic decisions on such application-oriented information as the "type of service" bit, explained Frank Dzubeck, president of Communications Network Architects, Inc., a consulting firm in Washington, D.C.

"It will look at the entire header, including what precedes the IP header, and execute based on what's in the actual content of the packet," Dzubeck said. For example, the switch could automatically recognize that the traffic is an IP telephony call, a video stream or an extremely delay-sensitive terminal-to-host session. If so, it would give the traffic a clean path through the IP network, while more delay-tolerant file transfers and messages wait.

By contrast, the Cisco 12000 GSR looks at a predefined set of six to eight "precedence bits" that roughly indicate the priority of each packet, Dzubeck said. Both Lucent and Cisco are claiming the ability to scale up to terabit speeds for upcoming releases of their respective IP switching platforms.

Lucent officials called the PacketStar switch "revolutionary," but end-user benefits - in terms of new carrier and ISP services keyed off the switch - could be a ways off. "The carriers are going to waltz into this," Dzubeck cautioned. "The trials are going to last a long time." To try to move carriers along more quickly, Lucent also announced new large-capacity IP access servers to compete with products such as those from Ascend Communications, Inc. that are popular with ISPs, as well as voice-to-data gateways.

The new IP products are significant for Lucent because, until now, its data networking strategy has been heavily focused on ATM switches for the enterprise and carriers.

Some large ISPs and Internet backbone providers are antagonistic toward ATM because they consider the protocol to contain a "cell tax" - a 5-byte header on every 53-byte cell, regardless of whether the payload is voice, data or video - and thus wasteful of bandwidth.

Lucent began diversifying away from ATM in the local area with its purchase last year of Prominet Corp., a Gigabit Ethernet switch vendor. Analysts said yesterday's announcement proves Lucent is eager to pursue both ATM and native IP strategies side-by-side in the enterprise WAN and carrier markets, just as it will be offering both ATM and high-speed Ethernet switching in LANs and campus networks.