Host-Based IDS (HIDS)
From Computing and Software Wiki
Host-based systems were the first type of IDS to be developed and implemented. These systems collect and analyze data that originate on a computer that hosts a service, such as a Web server. Once this data is aggregated for a given computer, it can either be analyzed locally or sent to a separate/central analysis machine. One example of a host-based system is programs that operate on a system and receive application or operating system audit logs. These programs are highly effective for detecting insider abuses. Residing on the trusted network systems themselves, they are close to the network’s authenticated users. If one of these users attempts unauthorized activity, host-based systems usually detect and collect the most pertinent information in the quickest possible manner. In addition to detecting unauthorized insider activity, host-based systems are also effective at detecting unauthorized file modification.
On the down side, host-based systems can get unwieldy. With several thousand possible endpoints on a large network, collecting and aggregating separate specific computer information for each individual machine may prove inefficient and ineffective. In addition, if an intruder disables the data collection on any given computer, the IDS on that machine will be rendered useless because there is no backup.
Possible host-based IDS implementations include Windows NT/2000 Security Event Logs, RDMS audit sources, Enterprise Management systems audit data (such as Tivoli), and UNIX Syslog in their raw forms or in their secure forms such as Solaris' BSM; host-based commercial products include RealSecure, ITA, Squire, and Entercept, to name a few.
