Thanks guys for the reply. I will elaborate more. The router has many VCs. Only one VC has the problem and it's a DS-3 connecting to the Cabletron SSR 8600, the main feed. It is the only VCs constantly accumulating CRCs and Length errors. All other VCs to the sub-sites have zero errors. Here is a sample of the errors: Hardware is RS8234 ATM DS3 Description: Uplink to ICN Internet address is 207.165.237.22/30 MTU 4470 bytes, BW 12146 Kbit, DLY 190 usec, reliability 255/255, txload 19/255, rxload 26/255 Encapsulation ATM 21403245 packets input, 13217734694 bytes 115262297 packets output,13745159548 bytes 0 OAM cells input, 0 OAM cells output AAL5 CRC errors : 318996 AAL5 SAR Timeouts : 1 AAL5 Oversized SDUs : 0 AAL5 length violation : 318210 AAL5 CPI Error : 0 And finally, when I do a debug of atm errors, no errors show. TIA! Marc Quibell Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=3821&t=3821 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]