Posted by Oink, oink on August 02, 2003 at 06:37 [212.159.85.34]
In Reply to: Re: Our points are both valid posted by Teach on August 01, 2003 at 15:25
Hi Teach,
Yes, I noticed that your IP address was from a different range. You're definitely not one of the posters from the south-west of the UK.
I am assuming that AOL use similar equipment and a similar set up in the USA as they do in the UK. If so, then...
Each part of the country will have a number (possibly as small as one) of routers accepting connections from their modem equipment from subscribers. These will allocate an IP address from their range. Most ISPs with modem connections use dynamic addresses - that is, they are allocated when you connect by modem and then are released for re-use when the modem disconnects. Having established a connection with you, the router then passes traffic from you to the Internet to the ISP connection on to a backbone (one of the main Internet 'highways') and, of more interest to you, has to route traffic from the Internet back to your computer.
For this reason, the IP address used for that routing has to be utterly unique in the entire world for the duration of your modem session. Two posts with same IP address at similar time - same computer. The only exception to this is private networks not visible to nor connected to the Internet (so this exception does not apply to posters on Internet message boards).
Now, AOL and other ISPs don't want to have 10 routers stacked up with only a handful out of thousands of ports in use at any one time so that ever user can get the same IP address whenever they connect. Instead, they have one or more routers with each port having an address then connect the modem to a free port when it activates. So, taking this router in south-west England as an example, its address range is set to 195.92.67.* The router box itself will be 195.92.67.0, a few more low numbers like 195.92.67.1 will be reserved for any test equipment that may need connecting and that leaves the rest of the addresses up to 195.92.67.255 for allocation to modem callers (by convention, a few addresses at the top of the range may be reserved and not used too). So, an AOL caller from that small part of the UK can get any IP address from around 195.92.67.10 to maybe 195.92.67.249 when they connect.
When they disconnect, it they reconnect within a few seconds, they generally get the same IP address again. If they are disconnected for more than a few seconds, the IP address and port are freed up and another caller can be given them. Generally, the next caller will be given the port and IP address that have been unused longest, but it depends on the router settings.
The consequence of that is that the same person using the same computer will probably get a slightly different IP address than the previous time they connected. So a different last number is definitely not proof that the poster is different. They could be different... or they could be the same person.
Now one thing we notice is that the 195.92.67.* posts are NOT spread over the whole range 195.92.67.10 to ...249. So, there is a distinct possibility that they are from computers related in some way. One possibility is an Internet cafe or a company using AOL as a service provider (one poster mentioned working for a travel agency once, which also fits this model). That would have a corporate deal with AOL, not just a personal one, and could well have been allocated the fixed IP address range 195.92.67.*. Companies tend to need a fixed address range as they have things like web sites on servers or communications traffic that rely on knowing the actual IP address involved and it not changing.
So the observed pattern of 195.92.67.* posts could also be from different computers in the same building with a corporate AOL connection, like a cyber cafe. In that case, of course, it is quite possible that one person or a small group of people use different computers in the same building to try to cover their tracks and generate slightly different IP addresses for different posts.
There... hope that satisfies your curiosity a bit! ;)