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New Member

Connecting HWIC-4T to WIC-1T through T1 PTP

Here is my problem. I am atempting to connect my 2821 with an HWIC-4T to my 2801 with a WIC-1T via a standard T1 PTP leased line.

After a router reboot or an interface shut / no shut the link will come up momentarily and then drop. I have tested the line and all the CSU/DSU equipment in the link by temporarily using another WIC-1T in the 2821 and the link comes up and it stable.

I need to use the HWIC-4T due to needing the port density for an upcoming expansion.

Any ideas?


Rod Sculthorp

Network Engineer

New Member

Re: Connecting HWIC-4T to WIC-1T through T1 PTP

Sounds like a timing issue. If this is a poing to point T1 one end must provide timing. If you are using the same external CSU/DSU's this might not be a problem, but if you are not you need to make sure one end is providing timing.

The other thing to check is to make sure you have HWIC-4T and not a HWIC4-AS. The reason this matters is because the AS only goes up to 256K.

If this does not work if you could post config info it would help.


New Member

Re: Connecting HWIC-4T to WIC-1T through T1 PTP

OK, thanks for the help. I will check out the timing issue and I know the card is the 4T since I had made the mistake with the 4AS in past.

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