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LCP negotiation problem


we have a new Cisco2600 with an E1-PRI-line.

We tried to dial to a Cisco1600 with 64k-BRI.

From C1600 to the C2600 the connection works fine.

From C2600 to the C1600 the fist step of the call-setup is OK, but when the routers starts the LCP-phase there is a strange problem:

Both Routers are sending LCP-CONFREQs:

From the C1600 to the C2600 the LCP-reqs are OK

From the C2600 to the C1600 the LCP-reqs are never arriving at the C1600. In the debug I can see the outgoing LCP-reqs but at the destination they are not incomming.

The C1600 is OK (it works fine with an AS5300).

The C2600 has the same problem when dialing to an ISP.

It is NO authentication problem, they even don't come until the ppp-auth phase.

Is it possible that the call setup is all OK until the LCP-phase and then the LCPs are blocked (maybee by our PSTN-provider) or is there another reason ?


Re: LCP negotiation problem

This could be a telco problem. check with telco. You can try for "speed 56" option in the on both ends.