Calls fail with different access code

[travisbarden]

We have CUCM 8.6 and two providers: AT&T and Paetec. Paetec is local and LD. AT&T is international and has CLID blocked.

Normally our users use access code 9 to make a call and it goes out the approriate connection. If a caller needs to force CLID blocking (typically for security purposes) they use a different access code, say 55.

If a user places an international call with 55, the call fails. If the user dials the same number but with access code 9, the call succeeds. At this point Cisco and AT&T are pointing fingers at each other. The call setup looks the same.

==========

This call was placed with 9 and it goes through:

030292: Sep 17 09:53:43.305 DST: ISDN Se0/2/1:23 Q931: TX -> SETUP pd = 8  callref = 0x0171

        Bearer Capability i = 0x8090A2

                Standard = CCITT

                Transfer Capability = Speech 

                Transfer Mode = Circuit

                Transfer Rate = 64 kbit/s

        Channel ID i = 0xA98397

                Exclusive, Channel 23

        Net Specific Fac i = 0x00E1

        Calling Party Number i = 0x2081, '2125555555'

                Plan:Unknown, Type:National

        Called Party Number i = 0xA0, '011999999999999'

                Plan:Unknown, Type:National

rtr06#

030293: Sep 17 09:53:43.369 DST: ISDN Se0/2/1:23 Q931: RX <- CALL_PROC pd = 8  callref = 0x8171

===========

This call was placed with 55 and it fails:

030278: Sep 17 09:53:17.284 DST: ISDN Se0/2/1:23 Q931: TX -> SETUP pd = 8  callref = 0x0170

        Bearer Capability i = 0x8090A2

                Standard = CCITT

                Transfer Capability = Speech 

                Transfer Mode = Circuit

                Transfer Rate = 64 kbit/s

        Channel ID i = 0xA98397

                Exclusive, Channel 23

        Net Specific Fac i = 0x00E6

        Calling Party Number i = 0x2081, '2125555555'

                Plan:Unknown, Type:National

        Called Party Number i = 0xA0, '011999999999999'

                Plan:Unknown, Type:National

030279: Sep 17 09:53:17.328 DST: ISDN Se0/2/1:23 Q931: RX <- RELEASE_COMP pd = 8  callref = 0x8170

        Cause i = 0x83BF - Service/option not available, unspecified

===========

Thoughts?

[paolo bevilacqua]

Perhaps  you're using MGCP ?

       Net Specific Fac i = 0x00E1

and

        Net Specific Fac i = 0x00E6

I am not sure  (haven't searched) from where how and why CUCM configuration generates these facilities, perhaps related to CLID blocking.

I can tell you how to block CLID on a per-call basis, but that would be using dial-peer and H.323 or SIP, not MGCP.

[paolo bevilacqua]

I have looked at TR 41459

http://www.corp.att.com/cpetesting/pdf/tr41459_99.pdf

Ihese should be decoded according to

3.6.5.19 Network-Specific Facilities

table III - 43

1st case:

service SDN (including GSDN) access and egress

2nd case:

service ACCUNET Switched Digital Service (including Switched Digital International) access and egress

Now, still not knowing how CM is selecting the different service (I'm not expert with CM), you have to look at which one is right for your calls. And you may need to set the calling plan/type to be ISDN/national.

Note: in both cases you are not restricing calling party number

0x2081 =

Type of number = national number

Numbering plan identification = unknown

last octet of the description

Screening indicator = user provided, verified and passed