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New Member

Need cable definition for 871 Router and USR Modem

I have tried three different RJ45 to DB25 adapters used for various Cisco routers. I am configuring this to remotely dial into the Cisco 871. I have a Case in the TAC but it is not going well.

Bill Bores

VIP Purple

Re: Need cable definition for 871 Router and USR Modem

Hello Bill,

I am not really clear on what you are asking: are you looking to purchase the cable somewhere, and what is TAC recommending ? Have a look at this link, it shows the cable you need (it is the blue cable with an RJ-45 connector at one side, and a DB-25 adapter at the other...).

Or are you having problems getting a (remote) connection from your modem to the router ?

Items Shipped with the Router



New Member

Re: Need cable definition for 871 Router and USR Modem

The router modem adapter cable does not come with the router, it is optional. So what I am looking for is what is the pinout from the RJ45 to the DB25 male end? Cisco has several different pinouts for the AUX port RJ45 to the DB25 modem connection. The one I need is for the Cisco 871 router. The 871 manual does not specify it, only that it exists.

Thanks much,

Bill Bores

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