Continuity Testing Call Flow (CCR/COT)

Continuity tests are used to make sure that the SS7 ISUP interface circuit groups (CIC) are aligned with the physical links (E1/T1) properly. Toolpack version 2.7 allows users of the TMG to do ISUP Continuity Testing via 3 methods by CIC Group or individual CIC:

Incoming Continuity Testing Outside A Call

This circuit testing occurs when one of the nodes wants to validate a currently idle circuit. It is recommended that the switch first blocks the circuit to prevent calls to use the circuit during the testing.

A successful test call flow is as below:

For ITU:

Peer SP                                        TMG

CCR            - - - - - - - - - - ->          

Check tone     - - - - - - - - - - -|         (timeslot loopbak)    
                - - - - - - - - - -

REL            - - - - - - - - - - ->

               < -- - - - - - - - - -          RLC

For ANSI:

Peer SP                                        TMG

CCR            - - - - - - - - - - -> 

               < -- - - - - - - - - -          LPA

Check tone     - - - - - - - - - - -|         (timeslot loopbak)     
                - - - - - - - - - -

REL            - - - - - - - - - - ->

               < -- - - - - - - - - -          RLC

Incoming Continuity Testing Within A Call

This circuit testing occurs when the forward side (originating side) sets the ‘continuity test required’ field of the ‘nature of connection indicators’ IE into the IAM message.

A successful test call flow is as below:

Peer SP                                        TMG

IAM           - - - - - - - - - - ->

Check tone    - - - - - - - - - - -|          (timeslot loopbak)  
              - - - - - - - - - - -

COT (successful) - - - - - - - - -->

             <- - - - - - - - - - -            ACM
 
             - - - - - - - - - - -             Ringing tone

             <- - - - - - - - - - -            ANM

Connectivity - -  - -  - -  - -  - -           Connectivity

REL          - - - - - - - - - - ->

             <- - - - - - - - - - - RLC

Outgoing Continuity Testing

Users of the TMG unit can generate out of call SS7 ISUP Continuity Tests via webportal easily.

A successful test call flow is as below:

Peer SP                                        TMG
            < - - - - - - - - - - -            CCR

            |- - - - - - - - - - -             Check tone
              - - - - - - - - - -

            < - - - - - - - - - - -            REL 

RLC          -- - - - - - - - - - ->    

Configuration

• Web Portal v2.7: Outgoing Continuity Testing