Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Community Member

T3 (DS3) circuit operation

Hi all,

Our company turned up two (subrate 9mb) MPLS DS3 circuits at a remote site last weekend.

I've noticed a few CRC errors on each circuit, but it doesn't appear to have any affect on performance. We've tested the load, and have no complaints from the user community.

Is there a threshold/benchmark for input/output CRC errors on a DS3 circuit? Should there be an at all?

It's a frame-relay PVC to the PE MPLS edge. The LMI count looks fine.

mpls-router-1>sh int s1/0

Serial1/0 is up, line protocol is up

Hardware is DSXPNM Serial

MTU 4470 bytes, BW 9022 Kbit, DLY 200 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation FRAME-RELAY IETF, crc 16, loopback not set

Keepalive set (10 sec)

LMI enq sent 35562, LMI stat recvd 35562, LMI upd recvd 0, DTE LMI up

LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0

LMI DLCI 1023 LMI type is CISCO frame relay DTE

FR SVC disabled, LAPF state down

Broadcast queue 0/64, broadcasts sent/dropped 5927/0, interface broadcasts 0

Last input 00:00:02, output 00:00:00, output hang never

Last clearing of "show interface" counters 4d02h

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 0 bits/sec, 1 packets/sec

5 minute output rate 1000 bits/sec, 3 packets/sec

5991143 packets input, 1388346109 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

3 input errors, 3 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

6594240 packets output, 741305236 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

DSU mode 0, bandwidth 9000, real bandwidth 9022, scramble 1

mpls-2-router>sh int s1/0

Serial1/0 is up, line protocol is up

Hardware is DSXPNM Serial

MTU 4470 bytes, BW 9022 Kbit, DLY 200 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation FRAME-RELAY IETF, crc 16, loopback not set

Keepalive set (10 sec)

LMI enq sent 43188, LMI stat recvd 43188, LMI upd recvd 0, DTE LMI up

LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0

LMI DLCI 1023 LMI type is CISCO frame relay DTE

FR SVC disabled, LAPF state down

Broadcast queue 0/64, broadcasts sent/dropped 7198/0, interface broadcasts 0

Last input 00:00:02, output 00:00:00, output hang never

Last clearing of "show interface" counters 4d23h

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 2000 bits/sec, 2 packets/sec

5 minute output rate 2000 bits/sec, 2 packets/sec

7003779 packets input, 3057692652 bytes, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

93 input errors, 93 CRC, 36 frame, 19 overrun, 0 ignored, 55 abort

6964010 packets output, 1382551929 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

DSU mode 0, bandwidth 9000, real bandwidth 9022, scramble 1

Thanks as always,

Mike

2 REPLIES
Hall of Fame Super Gold

Re: T3 (DS3) circuit operation

A telecom, a good value for BER should be 1 x 10^-6 that is one in a million. You're almost there but not quite. Check over time if the errors increase or perhaps was a transient situation.

Community Member

Re: T3 (DS3) circuit operation

Thanks for the reply, P.bevilacqua.

-M

502
Views
4
Helpful
2
Replies
CreatePlease to create content