2501 router and analog modem

[simonepezzano]

Good day everyone,

with all this DSL and cable connections, I completely missed the good old analog culture...

I have a 2501 router and I'd like to connect a 56k analog modem to the serial port for dialing out.

There only is a little problem... I'm clueless. Well, not completely, I already had some experieces with pppoe so I have an idea of how ppp works, but I'd really need some advice.

It's all about dialing out, I feel so stupid!

Thanks a lot!

[tepatel · Accepted solution]

Analog modem to a serial port will only work if that serial port is Sync/Async. So you need to enter command called "physical layer async" under the serial interface to make that as async. Here is the urls which talks about config and troubleshooting

http://www.cisco.com/en/US/tech/tk801/tk36/technologies_configuration_example09186a00801d2576.shtml

and also

http://www.cisco.com/en/US/tech/tk713/tk507/technologies_configuration_example09186a0080112d31.shtml

[vcjones]

Unless you have a 56K modem which supports a synchronous interface, you can't attach it to either serial interface on the 2501. But you can attach it to the AUX port and run PPP over that. However, that port is limited to 38.4 Kbps, so you won't go any faster than that with this router.

The magic search keywords are "dial on demand routing" and there are numerous examples to be found on www.cisco.com. A "Google groups" search of usenet postings (keywords: 2501 ppp aux isp) would also be productive, as this was a popular topic several years ago.

Good luck and have fun!

Vincent C Jones

www.networkingunlimited.com

[simonepezzano]

I see...

So if i attach it to the aux port, is it going to make me problems since I have an ethernet transceiver attached to the aui port?

[vcjones]

No problem. The AUX port and the AUI port are unrelated despite sharing two of three letters. (The former is an abbreviation for auxiliary port while the latter is an acronym for Access User Interface). Just remember that the phone line plugs into an external modem, which then attaches to the AUX port. If you plug a live phone line directly into the AUX port (don't laugh, it's been done more often then most people will admit), the AUX port will never work again.

Good luck and have fun!

Vincent C Jones

www.networkingunlimited.com

[simonepezzano]

Great! I KNOW people who tried to plug a rj11 into a rj45 socket...

You've been very helpful!

Thanks a lot!