Limiting Webmail (and other such services) on Public Access Workstations

Eric H. Schnell
Associate Professor
Head, Information Technology
Prior Health Sciences Library
The Ohio State University

   There is little doubt that email has become a valuable communications tool.  The technology helps teachers, researchers, and students to break down traditional communication barriers such as geography and time.  It enhances instructional interactions and can facilitate professional collaboration.  Additionally, real-time personal communication services such as chat and instant messaging are increasingly being used to supplement email.  While these tools are extremely useful, their availability as Web delivered services have placed libraries in a very difficult position.   

   Libraries often have a finite number of public access workstations which provide patrons onsite access to library resources.  The growth in the use of the Internet for personal communications has resulted in an increased number of customers using public access workstations for email and chat, as well as recreational activities such as online gaming.  Customers participating in these Internet communications and gaming can easily occupy a public access workstation for an hour or more.  This prolong use results in even fewer workstations available for customers wishing to use more "traditional" online resources.  

   To manage this issue, some libraries have posted signs to encourage time limit or have instituted sign up sheets.  While these methods work in the short run, they are generally unsuccessful in the long run since they are easily ignored or circumvented. Such systems also require library staff to police and mediate any scheduling conflicts. 

   So:

     How can libraries reduce personal communications and leisure activities at public access workstations in order to create more opportunities for customers wishing to access instructional and research resources?

Limiting Web Site Access

    This decision did not mean the library did not want the customers to access sports or NCAA basketball content.  In fact customers could, and did, access March Madness information from other sports sites.  By limiting the more interactive sites we found less people camping out and there was an increased turnover in workstation use.  This limit was taken off after the tournament was over.   

    While the NCAA site was a major motivator in creating a technical solution, the increasing number of Web-based personal communications services became the overriding issue.  The Prior Library is fortunate to have a 55 workstation lab designed specifically for personal communications and curriculum related activities. All Ohio State students, faculty, and staff had access to the lab anytime the library was open. Access in the lab is unrestricted. It was simply more convenient for many people to use the workstations on the 1st floor than going up to the 4th floor.

    The bottom line is that by placing some limits on the sites which can be accessed on the libraries pubic access workstations the library has had fewer customers spending hours at our limited number of workstations reading email, chatting, and even playing chess.  

The HOSTS File and a Simple Web Server

   An Internet workstation looks up a Web address using the the Domain Name Service (DNS). DNS translates alphanumeric domain names to a numerical Internet Protocol (IP) addresses. The workstation then uses the numerical IP number to contact the Web site.  Internet "old timers" will remember having to manually edit the Telnet application's config.tel file in order to associate IP addresses with more customer friendly names.   

   When the TCP/IP protocol was finally integrated into Windows 95, the config.tel file was renamed HOSTS.  It still contains mappings of IP addresses to host names, but it is largely overlooked and seldom used because of the DNS service. However, before the workstation goes to the DNS service it still takes a peek at the HOSTS file to see if any IP numeric address are contained there. If so, it does not refer to the DNS service but instead uses the HOSTS entry.   The HOSTS file was used to limit assess to specific Web sites.

   To fool the browser, and the customer, the domain names of the Web-based services we wished to restrict access to were associated in the HOSTS file to a single IP address.  This IP address belongs to a local Web server which delivers a single web page which informs the user that access to the site has been denied.  This Web page contains a short explanation as to why they got redirected from the site they wanted as well as a gentle reminder that the library has a computer lab for such activities.  The patron is then automatically sent back to the library's main Web  page. (Please do not send your users to our example site)

   In Windows 95/98, the HOSTS file is found in the root /Windows directory with the file extension .SAM (for sample).   In Windows NT4/2000/ME/XP, the HOSTS file it is found in the directory /winnt/system32/drivers/etc and usually does not have a file extension. Make sure to remove the .SAM file extension so the file name is simply HOSTS.  (NOTE: Windows often hides the extensions for known file types.)  

   One common problem in implementing this solution is that instead of saving the file as HOSTS, Windows adds the file extension .sam or a .txt.  To insure there is no file extension, switch the Windows Explorer default to show all file extensions.  The inadvertent addition of a file extension is the only reason the workstation may choose not to recognize the HOSTS file.

Macintosh Notes

   The Macintosh's hosts file format is based on RFC - 1035 (These is a very technical note. Save time by skipping to page 33 referring to Master File Format. ). Since Windows 95/98 does not use the same standard of Hosts file it cannot be ported over to Mac OS systems with Open Transport or MacTCP.  

   The Macintosh's Open Transport: TCP/IP Configuration supports a Hosts file that may be used to supplement and/or customize the Domain Name Resolver's initial cache of information. The MacOS keeps its HOSTS file in the Preferences folder under the System folder. The basic format of an entry is:  myhost.mydomain.edu A 128.1.1.1 

Conclusion

   This solution has significantly reduced the amount of Web-based email traffic and leisure time activities.  While a direct correlation has not been made,  our library's Web site has seen an increase in the number of in-house hits since we began to limit access to specific services. Interestingly enough, during the same time period actual gate count decreased.   

  Reality is that with every solution comes a workaround. No solution is 100% foolproof when there are clever students around.  If a customer knows the IP address of a service they can enter it and the workstation bypasses both the HOSTS file and the DNS server. However, many of the free email services use server clusters which make this difficult. Most patrons are also unaware of the workings of IP/DNS. Even so, we disabled the ability to exit to DOS so they are not able to use "nslookup" to find the IP address of a domain name.