James, you're preaching to the choir with all of that copy & paste stuff, and thowing in every networking word know to man, and then some. Here it is in layman's terms, for the benefit of those who don't have the decoder ring.
Every ISP runs an intranet of some sort (a.k.a. network). It can be 10 MB ethernet, 100MB ethernet, throw in some FDDI, whatever. As long as it supports TCP, it doesn't matter. It's just a network, regardless of speed and type.
You dial into a remote access server (RAS), or concentrator. Maybe the ISP lets you tap into the server statistics, maybe not. Maybe they let you have shell access, maybe not. Nevertheless, the RAS hangs off the intranet, at AOL, and at all other ISPs.
They also have news servers that hang off the network. The same for mail servers, and ftp servers, and DNS servers, so on. All of these servers are hanging off the network, whether you're AOL or any other ISP.
Also connected to the network are routers, that tell each TCP packet where to go, and network interfaces on each device, for sending and receiving TCP packets with their address on them.
Then we have our Internet gateway. Some ISP have only one, others have many. Some are high speed, some are very high speed, some are relatively slow. "Good" ISPs have many large gateways, thus allowing for a smooth flow of data to and from their network. Some don't provisio with adequate gateways, thus slowing traffic.
AOL runs a HUGE network, connecting all of their POPs (Points of Presence, or RA servers). That network is run by ANS, a subsidiary of AOL. ANS is itself a backbone like the ones you cited, except that it's sole customer (I think) is AOL.
MCI is a major backbone provider. Prior to their recent network upgrade, they were known as THE MAJOR bottleneck on the Internet backbone network. Hoever, they are now upgrading, and the improvement has been noticed by many.
By the way, what makes you think that AOL does place their POPS at the telco CO's just the same as the LD carriers? I think they do, and that's why they have standardized on USR Total Control Hubs, to give them maximum management control over theuir hundreds of POPs.
Personally, I prefer a good local ISP over AOL any day, but that doesn't mean that AOL isn't a force to be noticed and respected. We may not care for them as an ISP, but the fact of the matter is that they own the masses, and nobody else is even a close second.
David |
