How NetSpective^® is Updated

On startup, the Category Management process loads a cached list of sites, and their respective categories, from permanent storage in the Adaptive Filtering Library. The cache itself is generated using simple most-recently-used logic, where the cache list contains the most recently requested URLs. When the process cannot find a URL in its cache or permanent Adaptive Filtering Library storage lists, it sets the unknown URL aside for future processing.

Every day, a NetSpective unit will send the list of unknown URLs to the NetSpective Adaptive Filtering Lab servers for analysis. The results of the categorization analysis will then be published on a daily basis on an FTP server, accessible by the NetSpective unit for download. Once downloaded, the Category Management process will update its permanent and cache lists with the newly available information.

There are several advantages of this approach. First, the Adaptive Filtering Lab processes are based on well-trained neural network engines that are routinely retrained to classify Web pages through linguistic pattern recognition. Even if a page contains no text, the Adaptive Filtering Lab processes will attempt to identify links in and out of the page, so that it can come up with an intelligent decision as to the contents of a page. Another advantage is that NetSpective itself is not tasked with the process of classifying Web page content, focusing exclusively on the blocking process. Finally, since the Adaptive Filtering Lab receives, in an anonymous fashion, the requests of many NetSpective units on the field, every single customer receives the collective benefit of a high-quality categorization list, without the concern of excessive data due to invalid or non-existent URLs. In this way, the contents of the list are not based on arbitrary Web crawls, but on what each and every customer is surfing on the field.

There are two general update elements available from the Adaptive Filtering Lab on-line service (OLS). The first is the categorization update, which can be downloaded on a schedule configured via the administrative Web interface. The second is a general software update for the appliance, which will also be downloaded automatically as it becomes available. The software update is generally installed via the administrative Web interface, while the categorization updates are performed silently in the background.

Logging

NetSpective generates log files that can be analyzed with NetSpective's standard reporting software included with the NetSpective package. The log files contain the date and time, NetSpective system name, client IP address, protocol, action [blocked (1) or not-blocked (0)], category, and URL. NetAuditor provides 23 reports for the analysis of access trends and Internet usage policy compliance. Specific configuration details are available on NetSpective's standard reporting software. Installation In its simplest configuration, the NetSpective is deployed in a network by connecting both of its Ethernet cards to a passive hub, and properly assigning a single IP address and a network mask that covers all or a subset of the network to be monitored. Depending on the network configuration and licensing requirements, NetSpective can be connected in different segments of a network. For example, NetSpective can be deployed either behind a firewall or Internet gateway, or in a DMZ with valid public addresses behind a packet filtering router.