ancientmoon
@lucent.com
| Question about ISDN/ISUP interworking in Q.699
Hi!
I have a question about ISDN/ISUP interworking - q.699.
in section "3.1.1.3 Sending of the Address Complete Message (ACM)", it has:
c) En bloc receiving is used on the DSS 1 side and a Progress indicator information element (except with value No. 8, in-band information or an appropriate pattern is now available, No. 3, originating address is non-ISDN, or No. 4, call has returned to the ISDN) is received in a CALL PROCEEDING message or in a PROGRESS message.
Why these 'exceptions'? especially for the PI=8 in call proceeding case?
thanks,
ancientmoon |
