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Remote login via PSTN

Dear experts,

I prepare Cisco1841 as CE router of MPLS and need to set up US.Robotics 56k modem to connect to Cisco 1841.

This modem enable for me to login via PSTN when MPLS is down.

According to URL above, It seems that I need to connect like following

PSTN line----Modem --DB25--console cable --Cisco1841.

Is it right? and

Are there anyone who knows which port of Cisco1841 should be used?

I am wondering AUX port or Console port?

URL above says that I need to console port.

If console port in this case, what is there aux port for ?

Hall of Fame Super Gold

Re: Remote login via PSTN

In no PPP connection is required, use console port. Otherwise, use AUX and configure PPP.

Cisco Employee

Re: Remote login via PSTN

Traditionally, the AUX port is there to connect auxilliary devices.  The original use case was a T1 CSU/DSU with a serial port for management.  In that case, the AUX port allowed the router to provide IP address and port for telnet access.

In modern days, the AUX port server as a prot that cab provide character based or PPP based acces to ther router or external devices.

The console port is simplified with no modem or flow control but an AUX port allows flow and modem control.

For all intents and purposes, the AUX is just a flexible serial port as opposed to a restricted-use serial port (the console).

Console also has a number of special features like the ability to receive a dedlicated logging stream (logging console) and the ability to "break" into the router for diagnostics (when the BREAK function is enabled).

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