AOL Users – Multiple IP Addresses
A few days ago I was in a forum and someone mentioned that they noticed a discrepancy in their Web server logs. A visitor to their Web site was an AOL user, but they appeared to be making several requests from different IP addresses.
If you are on dialup, you will probably get a different IP address each time you connect to your ISP, however, it won’t change as long as up don’t log off. How did the AOL user have multiple IP addresses even if they didn’t log off? I will explain that phenomenon in this post.
AOL Proxy Servers
Unlike regular dialup users, AOL users don’t get assigned an IP address that will show up in a Web server’s log file. This is because when an AOL user makes a request over the Internet; the request goes through what is known as a proxy server.
A proxy server is a server that acts as an intermediary between a user and the Internet. This allows an enterprise to control security, caching and provide administrative support. The proxy server is the access point to the Internet from the internal network of an enterprise.
How does this relate to AOL users? When a user connects to AOL, they receive an IP address from AOL. When they make a request to a Web site, the request is sent to the proxy server. The server then sends the request to the respective Web server. By this time the request has the IP address of the proxy server, and not of the AOL user.
The Web server completes the request and sends the information back to the IP address of the proxy server. The proxy server then determines which user requested the data, and then forwards the information to the AOL user.
If the AOL user makes another request, it can be sent to a different proxy server with a different IP address. The Web server will then receive a request from the same user, but this time the IP address will associated with the new proxy server. In this scenario, the AOL user has made two requests to the same Web server, but from two different IP addresses.
Issues with AOL Proxy Servers
There have been some issues related to the AOL proxy servers and AOL users. One issue is that Webmasters can’t get accurate data about their Web traffic. Usually, Web traffic data uses the IP address to determine unique users. If you get one user requesting data through multiple proxy servers, each with their own IP address, your Web data may indicate more users.
Another issue has to do with the actual IP addresses themselves. Many times a Web site might prevent traffic from a specific IP address from accessing their site. If a Web site bans an IP address from one of the proxy servers, any requests by AOL users that are sent through that proxy server won’t be able to access the Web site. This has frustrated many AOL users in the past.
Since AOL uses proxy servers to connect their users to the Internet, you may see multiple IP address from a single user in your Web logs. Each request from an AOL user can come from a different IP address depending on which proxy server the request is sent through. Besides the skewed Web stats from the multiple IP addresses, AOL users can be frustrated if a Web site has banned any traffic from one of the proxy server’s IP address.