T1 Over Ethernet using Cisco ISR4451

[sblakely]

We're attempting to route T1 traffic into a T1 card in an ISR4451 router, to another ISR4451, and out a T1 card installed there. Currently it's just the two IRS4451 devices directly connected by a Cat6 cale. We've tried following the process of encapsulating the T1 traffic using a serial interface with an IP address but we're definitely missing something. I've included some config exceprts below and if anyone has any thoughts or tips they'd be much appreciated.

ISR4451-1

controller T1 0/1/0
 framing esf
 clock source line primary
 linecode b8zs
 cablelength short 110
 channel-group 1 timeslots 1-24

!
interface GigabitEthernet0/0/1
 ip address 10.131.0.11 255.255.255.0
 negotiation auto

!

interface Serial0/1/0:1
 ip address 192.168.1.2 255.255.255.0
 crc 32

!

ip default-gateway 10.131.0.10

ip route 0.0.0.0 0.0.0.0 10.131.0.10

ISR4451-2

controller T1 0/2/0
 framing esf
 clock source line secondary
 linecode b8zs
 cablelength short 110
 channel-group 1 timeslots 1-24

!

interface GigabitEthernet0/0/1
 ip address 10.131.0.10 255.255.255.0
 negotiation auto

!

interface Serial0/2/0:1
 ip address 192.168.2.2 255.255.255.0
 crc 32

!

ip default-gateway 10.131.0.11

ip route 0.0.0.0 0.0.0.0 10.131.0.11

[Giuseppe Larosa]

Hello @sblakely ,

the Fluke instrument is not sending anything

Encapsulation HDLC, crc 32, loopback not set
Keepalive set (10 sec)
>>>  Last input 1w0d, output 00:00:08, output hang never

Please note that Cisco HDLC has a proprietary extension with a protocol type in the header if the instrument does not support Cisco HDLC you should move to enc ppp as already suggested by M02@rt37 .

Your test setup cannot be used to demonstrate the CEM capability you would need two instruments with the loop on the ISR2 the best result you can get is to send traffic destined to the ISR2 T1 serial interface but no way to receive traffic back to the instrument port.

the CEM configuration circuit emulation is what you need but to test it you need two external devices  and of course you also need the appropriate configuration.

Hope to help

Giuseppe