Serial line protocol issue - Cisco 1602

[jordan_christi]

Our 1602 router with onboard CSU/DSU has worked fine for the past 12 months and now data is not passing through. It indicates "Serial0 is up, line protocol is down". It is also showing many, many interface resets. DSD, DSR, DTR, RTS, and CTS are all up.

We are connected to a wireless data provider via a leased 64k telco line.

Any help would be appreciated.

[Josef Oduwo]

If you haven't changed anything on your end, I would place this squarely on your Telco:

1. Check for a hardware or cabling problem.

2. The remote CSU/DSU could be having issues.

3. A high error rate, especially if your CTS & DSR signals are toggling, points to a Telco issue.

Josef.

[thisisshanky]

What kind of alarm lights do you see on the CSU

[jordan_christi]

There are no alarm lights. The indicators on the back show that it detects a carrier, there is no alarm, and it is not in loopback mode.

[Josef Oduwo]

I am pretty sure this is a Telco beef, what are they saying?

Josef.

[jordan_christi]

Bellsouth claims everything is fine on their end . . . so I keep running in circles with them. I'll call them out again and maybe I will get lucky and they will fix the issue.

Thanks for the help.