Switch vendors crunch Gigabit chips

Companies such as Broadcom and Agere Systems are working to squeeze more Gigabit switch port controllers onto one chip. For switch buyers, this could result in lower-cost, feature-rich gear that is less prone to failure.

It's a job with contradictory goals for these switch component makers, which must think both big and small - bigger as in bandwidth, smaller as in the size of the components they make. They face the same challenge as makers of any business or consumer computer gadgets, from blade servers to laptops, PDAs or cell phones - producing smaller, faster and less expensive products. But the biggest problem is heat and power consumption.

Along this line, Broadcom in October released a low-power Gigabit Ethernet physical layer transceiver chip for Gigabit Ethernet switches, blade server interconnects or server network interface cards. The vendor says its chipset consumes 25% less power than its previous Gigabit Ethernet physical layer transceivers, but still provides enough signal power to transmit Gigabit Ethernet over "marginal" copper cabling plants, such as Category 5 or older Category 5e wiring.

This month, chipmaker Agere will launch a 48-port Gigabit Ethernet switching system that fits on a single system-on-a-chip product. The product has seven sub-components and uses less than half the number of chips as competing system-on-a-chip vendors, Agere says. The vendor also says its product takes up 30% less space than 48-port Gigabit chips that are currently shipping. This can help switch vendors pack more feature-based ASCIs and network processors into a system, while reducing the complexity, and potential for failure, of a 48-port chip system.

Part of this chip-crunching exercise is the conversion of the analog physical layer (PHY) processing components of a switch connection to a digital process. This lets the PHY component be built into the other Layer 2/3 switching pieces of the product.

"We've moved a lot of complexity in PHY into the digital domain," says Ngazi Bell, marketing directory at Agere. "You're able to have better signal-to-noise ratio because bit-error rate management happens digitally."

Bell says this type of work is being outsourced to silicon vendors, as switch vendors look to cut costs and focus on advanced features, such as management or security.

Switch makers "are trying to add value at the software and applications layer where they can differentiate themselves," Bell says.

She says these smaller systems also lead to more reliable end products. "Having only seven components in a 48-port switch reduces the complexity, heat and power consumption," which makes products less prone to failure, she says.

Agere and Broadcom both supply Ethernet semiconductors to 3Com, Cisco, Extreme Networks, Foundry Networks, Nortel and others.

Switch vendors are demanding more ports in a tighter space, and this is driving new technologies from component vendors.

"Density is certainly being driven up by switch vendors, which is a result of demand from end users," says Zeus Kerravala, an analyst with The Yankee Group. "More users and nodes connected to the network mean more [port] density is required."