Cisco Systems Inc. Monday plans to announce an upgrade of the Internetworking Operating System software for its flagship Catalyst 6500 Series switches, supporting increased modularity that"s designed to improve operational efficiency for IT managers.

The new features, which are scheduled to become available on some Catalyst 6500 models late this year, should enable faster restarts of the switches and reduce the time it takes users to install software upgrades, said John Yen, senior manager of switching product marketing at Cisco.

The updated switch offering is based on technology built into the CRS-1 carrier-class routing system that Cisco introduced in May 2004. Overall, the technology has been in the works for the past three years. Asked why the technology wasn"t available sooner, Yen said, "It takes this long for something like this."

American Century Investments in Kansas City, Mo., has tested the enhanced IOS on 60 Catalyst 6500s during the three-year development cycle, said Dave Rogers, senior IT network manager at the financial services firm. He estimated that the increased modularity will reduce the time American Century spends upgrading the software on all 60 switches from six weekends to about six hours.

"This capability actually allows us to do software upgrades immediately without production downtime or waiting until a scheduled maintenance window," Rogers said in an e-mail interview.

American Century plans to install the upgrade next year, Rogers said. He noted that the software will also allow automatic recovery of a single networking process within a switch without interrupting the flow of data for other processes.

For example, if a routing table gets corrupted and needs to be cleaned up and restarted, the new capabilities in IOS will enable that work to be done without affecting functions such as the management of port configuration data, said Zeus Kerravala, an analyst at Yankee Group Research Inc. in Boston.

Previously, IT shops have had to resort to shutting down entire switches to perform maintenance tasks, often on weekends, Kerravala said.

He added that Juniper Networks Inc. offers similar functionality on routers but not switches, while Extreme Networks Inc. supports some of the capabilities on its switches. But the Catalyst 6500 installed base is enormous, and users have been asking for the functionality for a long time, Kerravala and others said.

"The IOS update is a pretty big one," said Mark Fabbi, an analyst at Gartner Inc. "It will certainly make the life of network operators easier. I"ve always considered one of Cisco"s Achilles" heels to be operations, and this clearly helps make things better."

Yen said the update will be added to Cisco"s IOS 12.2SX release in the fourth quarter for users of the Catalyst 6500 Supervisor Engine 720, which is aimed at data center applications. The new features are due to become available in the first quarter of 2006 for customers using the lower-end Supervisor Engine 32.

The update also includes new software that can help IT managers automate routine tasks, Yen said.