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New Member

BRI backup for Leased line

Hi there,

I have two 2501 ( 02 Serials) connect two offces together. on each Router 2501 we have sued 01 Serial for 512 Kb/ leased line. Now I want to ahev the second Serial port to be configured as ISDN dail-up back up for the Primary line. My questtion is whether or not i can put in two BRI ISDN TA ( Modem) at to end and configure the second Serial as ISDN dial-backup ? How the configuration would be ?


New Member

Re: BRI backup for Leased line

I dont think that you can connect ISDN modem on serial sync port, or you'll have to look around if there are ISDN modems that support sync comunication with the DTE. On the other side if your serial port can be configured in async mode than there is no problem to do it.

Hope this helps


New Member

Re: BRI backup for Leased line

Dear Mr. phs1234,

You can use second serial port as ISDN back up but for that you'll have to use NT-1 and adapter.