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January 15, 2003

Web Watchers

By Antone Gonsalves

Whether you're looking to block objectionable content or curb students' surfing appetites, the latest filters can help.

In 2001, the National Center for Education Statistics found that 98 percent of public schools had drawn up acceptable use policies defining the rules for Internet use on campuses. Of those schools, 74 percent were using some form of software to filter the Web's estimated 2.1 billion pages-a number growing at a rate of 7 million a day. As educators are well aware, driving this adoption is the Children's Internet Protection Act, which requires schools to use filtering software in exchange for E-rate and Title III technology funding.

In general, filtering technology enables administrators and teachers to either limit access to specific sites, or to block access to unsuitable sites listed in a database. The best filtering products can be customized to let schools choose which sites to prohibit by categorizing them in groups. Vendors provide dozens of categories, such as violent acts, weapons, and racism, and often update databases daily.

In addition to its primary function of barring offensive content, filtering has also become an important tool for schools to reduce spam, free up bandwidth, and limit activities that would distract kids from their schoolwork. For example, most vendors extend their product capabilities to also filter or block instant messaging, chat rooms, and e-mail.

Filtering products are often sold as software or stand-alone appliances that can be integrated with third-party software. Because most schools or districts have their own computer networks, filtering software is best deployed on the proxy server that also runs network firewalls and antivirus software. Proxy servers are the gateway through which all communications pass before entering a network. In some cases, Internet service providers offer filtering software as a service built into their monthly fees.

Typically, reporting tools are included to give technology coordinators a view of Internet usage, such as sites visited most often, number of sites blocked, usage by individuals or groups, and more. Some products can also notify teachers and other school staff whenever a student tries to access a site that's off-limits.

Of course, because adult sites and many others continuously change Web addresses, no filtering software can prevent children from ever catching a glimpse of inappropriate content. However, today's products can go a long way toward reducing the chances.

BASCOM describes its Global Chalkboard Solution as more of an Internet tool for educators than as filtering software. The product enables teachers to integrate Web-based resources into the curriculum while preserving their ability to locally manage Internet use. Teachers can generate reports on sites viewed, both allowed and not allowed, and block e-mail and chat room usage as well. The Global Chalkboard also offers a regularly updated online catalog of educational Web resources, a Web caching system, and a firewall that can operate alone or be integrated with an existing firewall. Prices are based on configuration. (888) 922-2726

Marshal Software's SchoolMarshal checks Web pages, e-mails, attachments, and downloads entering the network, blocking items based on filtering rules set by the school or district. Schools program their own rules to customize Internet access levels for different groups of users and can generate reports based on criteria of their own choosing, such as peak times of system use. Other features include the ability to delay delivery of large e-mail files until off-peak times and immediate notification to the user and school officials of blocked activity. Licensing fees range from 50 cents to $1 per computer, depending on volume. (678) 420-1960

N2H2 sells a software plug-in that adds filtering to network operating systems offered by Microsoft, Cisco, Check Point, Novell, Volera, and SonicWALL. The company's URL database lists 4 million sites in 42 categories, which are identified by a full-time staff assisted by artificial intelligence technology. Network administrators can set access levels based on IP addresses, user, group, or time of day; and have the ability to provide users with temporary access to blocked sites. In addition, the software can block specific file types, such as MP3s, and notify school staff when a particular user accesses a specified category. Prices start at $1,113.60 per year for one to 50 users. (800) 971-2622

Net Nanny Software recently released a new version of its namesake filter. Net Nanny 5 contains 25 new or enhanced features, including filtering of inappropriate content based on site lists and keywords. In addition, the software blocks instant messaging, file sharing, online games, and pop-up advertising. Net Nanny runs on individual computers, not on a proxy server, and sells for $39.95 per desktop. (425) 709-8520

Palisade Systems's ScreenDoor Web-filtering appliance allows network administrators to set rules enforcing a school's acceptable use policy. The company's URL database blocks several million Web sites organized in 25 categories using a list licensed from SurfControl. Schools can set their own access rules for any combination of users or groups and generate usage reports. Besides Web sites, the product can be configured to block e-mail, instant messages, chat rooms, and streaming media. Prices start at $2,635 for appliance and license. (888) 824-0720

Secure Computing's SmartFilter includes a "control list" containing over 2 million sites organized in 30 categories that schools can choose to block. The software can also prohibit access by file types, such as MP3s and graphic files, and can block search engines from returning results when certain key words are used. Schools can customize access by defining user groups and enforcing different filtering rules for each group. SmartFilter installs on proxy servers or is pre-installed on caching appliances and firewalls. The annual base subscription is $25 per user for 50 to 99 users. Education discounts are available. (800) 379-4944

Security Software Systems's Cyber Sentinel Network captures the screen of possibly objectionable material accessed by a student and then reports the activity to network administrators. In addition, the product provides monitoring of network traffic and rules-based blocking of Web sites and content found in e-mail, chat rooms, attachments, and Instant Messages. The software has built-in time management so schools can control the hours in which students have access to the Web, e-mail, newsgroups, or other network services. Prices range from $29 to $49 per computer, depending on volume. (888) 835-7278

SonicWALL's Pro 100 Education Edition is a security appliance that in addition to offering firewall, antivirus, and security management, includes content filtering capabilities. Using a list from CyberPatrol of 12 categories from a database of over 1.5 million sites, SonicWALL's content filter monitors usage and controls access to Web content according to a school's or district's acceptable use policy. Network administrators can make filtering active during certain times of the day and block sites by list, keyword, or file type. The appliance, which costs $1,195, includes a firewall, VPN client, and a one-year free subscription to the Content Filter List. (888) 557-6642

St. Bernard's iPrism filtering appliance monitors, blocks, and reports on Internet activity within schools. The appliance's database contains 60 categories spanning millions of Web sites. Network administrators can assign filtering profiles to individual users or groups. The software can generate Internet usage reports on blocked sites, URLs accessed, type of content, time spent, and bandwidth used. Staff can be automatically notified by e-mail when certain URLs are accessed or when bandwidth and time thresholds are reached. iPrism includes a one-time cost of $2,195. Subscription plans are available for one to three years, and prices vary by the number of users. (800) 782-3762

SurfControl Web Filter features advanced customization, user notification of blocked sites, faster filtering through caching of Web pages, and the ability to block files that are virus-infected or take up too much bandwidth. The company's content database of 5 million sites covering 900 million Web pages is organized into 40 categories with 130 subtopics. Access can be managed several ways, including by user name or group name. The software comes with more than 50 report options, including a Blocked Category Summary and Top 10 Sites Visited. The base price is $18 per user for 500 users. (800) 828-2608

Symantec Web Security combines antivirus and Web filtering software in one package, with content filtered in 31 categories and 14 languages. In categorizing Web sites, Symantec combines both a traditional URL database approach with patented technology that examines the context of HTML pages. While Symantec identifies inappropriate sites, school personnel can override or make any exceptions to content classifications contained in the URL database. Staff also can set access levels by user, machine, or group, and generate reports based on these settings. Prices start at $43.40 each for 10 to 24 desktops; $35.10 each for 100 to 249 desktops. (800) 745-6054

Vericept's VIEW Filter analyzes all TCP/IP traffic on a network, including e-mail, chat, and instant messaging, and logs activity that falls outside rules set by network administrators. The software uses both a linguistics analysis engine to scan the content of network traffic and a URL database to block inappropriate URLs. Schools can set access levels based on login name, IP address, or time of day. VIEW Filter is capable of generating reports on activity by user, most frequently accessed sites, inappropriate activity, and other criteria. The software costs $2,500 per appliance, plus $12 to $25 per desktop, depending on volume. (800) 262-0274

Websense Enterprise enables districts and schools to block as many as 81 categories representing 3.7 million sites and more than 800 million Web pages in 44 languages. Company analysts categorize sites through a combination of proprietary software and human evaluation. School staff can set up Internet access by user, group, computer, or network, and can generate more than 60 report formats. Unrecognized sites are automatically reviewed and added to the URL database if they fit a school's rules for unacceptable sites. The software costs $15 per user, per year. (800) 723-1166

Antone Gonsalves, former senior editor at InformationWeek, is a freelance technology writer based in San Francisco.

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