WASHINGTON, D.C., Jan. 28, 1992 -- Cisco Systems has introduced a memory card that supports Flash EPROM circuits, which allow faster and more reliable software upgrades to the company's internetworking products.
The new CSC-MC+ Flash Memory card is available with Cisco's AGS+, MGS and CGS router/bridges; ASM and MSM terminal servers; and CPT protocol translator.
Rick Johnson, Cisco's router product manager, said the Flash approach involves booting the internetworking device from a software image stored in Flash EPROMs, electrically erasable and reprogrammable non-volatile circuits. The Flash approach is superior to other widely supported methods: booting from local floppy disks, physically replacing PROM chips when updating system software, or loading new software over the network from a file server each time the system restarts.
Most internetworking devices today boot from local floppies, Johnson said. "It's a slow process that takes from four to six minutes. Floppies are also subject to read/write errors and mechanical failures, have limited storage capacity -- usually 1.4 megabytes -- and must be protected from harsh environments such as manufacturing facilities."
The Flash Memory card contains 4.0 MB of Flash EPROM program memory plus 64 KB of configuration memory. Typical software load time is 15-20 seconds, typical erase/reprogram time two to three minutes.
The approach of removing PROMs from a router board and plugging in new ones "gets the router functional again very quickly, but in large enterprise-wide networks where routers are dispersed across a campus, for example, this is time-consuming and difficult to coordinate," Johnson said.
"Netbooting, while easier, is slow and makes a router dependent on the availability of a network connection and a file server. If a power failure brings the network down, for example, no router can resume operation until the load image is netbooted from the file server."
The Flash Memory card has the advantages of the latter two approaches without their drawbacks, Johnson said. "Booting from Flash memory is as fast as from standard PROMs, and, like netbooting, it allows fully automated distribution of new software to network devices. But those devices need no longer rely on network connections or the file server."
The Flash Memory card also can help provide the security that is critical to a growing number of networks. Cisco provides a security feature to prevent reprogramming of the Flash EPROMs. Because the card can be changed only from a password-protected session on the local console terminal or remotely via Telnet or DEC's MOP protocol, it also enhances system-wide security.
The CSC-MC+ card connects to the MCI (Multiport Communica- tions Interface) card installed in the Cisco chassis, replacing the CSC-MC memory card. Because it does not occupy a card slot in the chassis, the user loses no interface connections.
Cisco will continue to support both the PROM replacement and netbooting methods of software upgrading.
Posted: Feb 10 14:49:26 1992
