dial-up access to internet

Answered Question
Mar 28th, 2009

Hi every body!

Please consider a dial-up access to AOl for internet

Consider a internet user who uses AOL to connect to internet using dial-up. His modem dials one of the numbers given by AOL isp to connect to AOL pop.

AOl pop has a large bank of modems that users dial into .

If i have to connect two pc at different location using dial-up, i need to modem at each side.

Is same true for a user who dials into AOL pop ? Does it mean if 10,000 users want to connect using dial -up. AOl needs 10,000 Modems in its pop?

Aol tells its customer which number to dial in order to connect its pop. How many modems are mapped to single phone number at pop?

Thanks a lot!

I have this problem too.
0 votes
Correct Answer by lamav about 7 years 7 months ago

Yes, one modem per connection.

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Overall Rating: 5 (1 ratings)
lamav Sat, 03/28/2009 - 07:19


Funny you should ask this question about legacy Internet access, since I used to be part of a team of UUNET implementation engineers who used to build out AOL's dial-in infrastructure around the country.

To answer your question, AOL issues its users a phone number that their modem should dial to access the AOL network. That number is part of a hunt-group, in which calls rollover from modem to modem as the calls come in.

When the modem on the AOL side answers the call, a session is negotiated between the two modems, taking into consideration the quality of the dial-up POTS line. Good quality means high data rate of exchange, with data rate decreasing as quality decreases. This is called the "handshake."

These modems were typically deployed in proprietary configurations in a self-contained cabinet of equipment that included high-density modem modules HDMs (24-modems per HDM at that time, with each shelf containing 15 HDMs); T1 D4/AMI or ISDN PRI circuits terminating on the HDMs; a UNIX-based "server" (shelf-mounted, too) that bridged the data traffic from the DTE side of the modem to the LAN interface of a Cisco 3640 access router.

The router would prvide the IP connection to the AOL FEP (front-end processor) in Virginia.



sarahr202 Sat, 03/28/2009 - 08:12

Thanks a lot Victor!

Am i correct to support 10,000 users at a time AOL needs 10,000 modems at POP ?

Correct Answer
lamav Sat, 03/28/2009 - 08:24

Yes, one modem per connection.


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