Top Performance ACEswitch did well in our bandwidth tests, topping out at slightly less than 96 Mbps (without gigabit interfaces) for Fast Ethernet, which was better than any other load-balancer we've tested. In our T3 bandwidth test, the ACEswitch's performance was comparable to that of the leading load-balancers, with throughput around 32 Mbps. Its error counts were extremely low, beating all but Bright Tiger Technologies' ClusterCATS.

In our Gigabit Ethernet tests, the client cluster was linked via a single Gigabit Ethernet connection, as were the servers. We ran numerous tests of the switch's load-balancing functionality in a Gigabit Ethernet environment and measured throughput during the tests. After increasing the number of clients to better accommodate the available bandwidth, we finally ran out of client power. However, we had generated more than 350 Mbps of HTTP traffic using our scripts and client cluster. We suspect ACEswitch is ultimately capable of much more.

All Alteon switches also have a Layer 4 filtering feature that gives administrators the ability to allow, deny or redirect traffic. The ACEswitch 180s we tested were capable of maintaining 224 different filters. Each filter is based on source and destination IPs, protocol type and application source and destination port. Filters are maintained in the switch's filter table and are assigned to each port based on the filter index--the lower the index, the higher the precedence. For example, Filter 1 will always be processed first. Any traffic that passes through this filter is subject to any other filters assigned to that port beginning with 2, then 3 and so on. Administrators can filter various traffic types, adding security to a Web cluster or network. And for further security, filters can generate syslog messages.

Send comments on this article to Greg Yerxa at gyerxa@nwc.com.