What this software does is distinguish between regular server process behaviour and viruses to detect an attack. It can tell a rogue process such as a worm or virus from a regular, wanted process. Partially, this works because a worm or virus tends to be making the same type of connection at a much more frequent pace. HP's new software detects these kinds of patterns and acts accordingly. The faster a virus is set to propagate, the easier it is to distinguish it from conventional computer tasks. Processes identified as virus like are slowed down - effectively choked off - to prevent further damage and buying System administrators time to deal with the problem.
HP would not say when a PC version of the software will be available, or whether it will be available for Linux or not. But since initial demonstrations were on Linux, this seems reasonable. The software will be released for servers some time early in 2005.