Overture Networks scales down its switches

On Monday, the company introduced the ISG 2200, a scaled-down version of its ISG 5000 switch, which is designed to provide tenants in large office buildings with packet-based Ethernet services in addition to traditional connections. The ISG 2200 is a compact, less expensive switch designed for smaller locations.

Ethernet traditionally has been used in corporate networks. But now carriers are using it as a wide area technology to connect various buildings together in metropolitan area networks. Metropolitan Ethernet enthusiasts claim the technology is cheaper to install, because Ethernet gear typically costs about 40 percent less than traditional technology called SONET/SDH (Synchronous Optical Network/Synchronous Digital Hierarchy).

They also claim it is cheaper to operate. On Monday, the Metro Ethernet Forum, a marketing group made up of equipment vendors and service providers, published results from a study stating that Ethernet could save carriers roughly 23 percent annually on operational costs.

While carriers may be interested in taking advantage of some of the benefits Ethernet has to offer, they aren't jumping at the chance quickly. In fact, many incumbent carriers are taking a slow, staged approach to launching their metropolitan Ethernet. The main reason is that many have already invested in expensive SONET/SDH gear.

This is where Overture and other multiservice switch makers come in. Overture is targeting service providers that have already built extensive SONET/SDH networks. With the Overture products, carriers don't have to build a separate network to deliver Ethernet services; they can use the same SONET/SDH infrastructure they use to deliver packet-based services.

Carriers also are leery about giving up the benefits of their SONET/SDH infrastructure. Unlike Ethernet and Internet Protocol, SONET/SDH has mechanisms built into it that guarantee recovery from failures within 50 milliseconds. These short recovery times are essential for networks that carry voice traffic.

Ethernet by itself doesn't have these mechanisms for recovery and relies on algorithms used in IP. But because Ethernet and IP were designed for data and not voice, these recovery times can take up to several seconds--an unacceptable range when it comes to voice traffic. Overture and other metropolitan Ethernet equipment providers say they support new technology that provides sub-50 millisecond restoration and recovery.

Regardless of these challenges, analysts expect the metropolitan Ethernet market to escalate over the next several years, as carriers start to replace older, SONET/SDH gear with new Ethernet-enabled equipment. Infonetics Research projects the entire Ethernet equipment market will grow more than 150 percent to $7.5 billion by 2007.

But it won't be an easy road for start-ups, especially because dominant players such as Alcatel, Cisco Systems, Fujitsu and Nortel Networks also offer products. Appian Communications, another small start-up competing in this market, recently ran out of money and closed its doors, according to reports from industry Web site Light Reading.

While Overture hasn't announced any big customers yet, it said it has installed gear in more than 100 locations. PPL Telcom, which serves multiple metropolitan areas in Pennsylvania, Maryland and New York, has been using the ISG 5000 for several months. Unlimited Fiber Optics Communications, based in San Francisco, also is installing the ISG 5000 to help deliver Ethernet services to its customers.