Backup Lines (ISDN)

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Jun 18th, 2006
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Hi All,

I would like to get an idea of what hardware i will need and sample configuration for the following scenario:

I have my main site with a 3745 router.

My district offices (5 of them) have 1841 router.

I have ISDN lines installed at all district offices and also at the main site.

My districts are connected to the main site using FR-->ATM . I would like to have the capability of dialing from the district to the main site in case the FR is down. So basically i want it for backup line.

Any ideas on hardware needed,

can all districts connect by ISDN to main site or only one at a time ???

I believe that the ISDN will be not used untill the DR goes down ??? is that correct ??

Also, can you give me sample configurations or point me somewhere to get some more info ??



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spremkumar Sun, 06/18/2006 - 22:56
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Whts the backup bandwidth you require over there between your locations...

Also the available free slots on both your 3800 and 1800 routers ...


dukenukem Mon, 06/19/2006 - 02:42
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I presume i can get 128 kbps with the isdn modem right ???

Could i multilink ppp with 2 isdn modems to get 256 ??? or even more ???

On the 3745 and i have 3 free slots.

On the 1841 i have one free slot.



spremkumar Mon, 06/19/2006 - 04:16
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You can have the following ISDN BRI cards installed in your Cisco 1841 to have the isdn connected and have ISDN backup connected to your central location when your primarly link goes down.

1) WIC-1B-U-V2 2) WIC-1B-S/T-V3

Cisco 3745 supports these ISDN BRI cards which you can have it in the central location.

1) WIC-1B-S/T 2) WIC-1B-U-V2

Using multilink you can get 128Kbps from a single ISDN line.



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