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Make My Day When testing a beta version of the CrossFire #8600 in our lab, this switch's latency seemed very low, a mere .05 milliseconds (ms) to forward a packet, which is excellent. To test its throughput capability, I threw a bunch of wire-speed connections at it, just to see if it would start dropping packets or delaying them. I continued to measure the switch's latency with a Network General Corp. Sniffer. It increased very little as I shotgunned additional data through its ports using our other analyzer's traffic generation feature. It didn't drop any packets, either, which was both unexpected and gratifying. Olicom says the switch can sustain wire speed on all 20 ports simultaneously, thanks to its 520-Mbps internal bus.

I tested the switch's autoconfiguring por ts by throwing 4- and 16-Mbps connections, hub-based connections, workstation-based connections, and full- and half-duplex c onnections at it. To test its DTR (Dedicated Token-Ring) interoperability, I connected a Proteon P1392 to it at full duplex and encountered no problems.

Although the switch normally tries to configure itself for the best possible performance and compatibility, you can manually disable features like cut-through switching in favor of store-and-forward on a port-by-port basis. (For example, if one of your rings is giving you an intermittent problem, you wouldn't want to propagate it to all of your rings.)

I'll Be Back Although Olicom's GUI manager is attractive, installs in a snap and is easy to use, the real management firepower lies within the switch itself. It's well-armed with Simple Network Management Protocol (SNMP), Remote Monitoring (RMON) and a standard-issue character-based VT100 interface, which is accessible through a serial connection or telnet. Using this menu-driven interface, you can configure all of the switch's settings and get statistics on the switch as well.

The GUI m anager thoughtfully includes a combination BOOTP-TFTP server for booting and firmware downloads. This utility runs on any Windows workstation--convenient if you don't want to rely on the kindness of your Unix administrator.

In addition to firmware upgrades, the switch also allows off-line backup and restore of its configuration via TFTP.

Jonathan Feldman is technical systems manager for the Chatham County Government in Savannah, Ga. He can be reached at jonathan@co.chatham.ga.us.