[SIPForum-discussion] how CLIR works in SIP[with PSTN]?

[Suh, Young Suk (Don)]

Hi!

as I 'm understanding that "From" field in INVITE can deliver the
information for CLIP(Calling Line ID Presentation) and CLIR(Calling Line ID
presentation Restriction) processing in the destination or UAC.



in case of PSTN signaling, especially on SS7 ISUP. "Calling Line ID" is
always delivered to destination regardless of service destination or called
party has.
you know, CLIP is one of the Cd(Called) party's service while CLIR is for
Cg(Calling) Party's.

       Cg   -----IAM------> Cd

(if Cg has no service, then IAM includes "CgID" and "presentation
indicator" is "allowed")
(else if Cg has CLIR, then IAM includes "CgID" and "presentation indicator"
is "restricted")
===> so,
(if Cd has no service, nothing has to be taken for displaying)
(else if Cd has CLIP then
     (if IAM presentation indicator is allowed, then CgID has to be
displayed"
     (if IAM presentation indicator is restricted, then CgID won't be
displayed, only "CgID restricted" instead)

I think this is the way PSTN go with,anyway..




However, SIP-T(rfc3398) procedure, shown in section 12.1 and 2 mentions
that "CgID" won't be delivered because it's going to be set to
"anonymous at ttt.uuu.ooo" instead of "xxxyyyzzzz at ttt.uuu.ooo".. like..

   From: Anonymous <sip:anonymous at anonymous.invalid>



if so, in SIP ---> ISUP interworking case, and Cg has "CLIR" service, then,
IAM in ISUP will NEVER include "CgID"(of course, there's no "presentation
indicator" attached either). this sure is different than PSTN only case.
and this is what most of Service Provider who currently wants to adapt SIP
network into their PSTN complains.. because, in this case, it displays
"CgID unavailable" other than "CgID restricted" unlike PSTN only case does.
so,



Isn't there anyone who faced with this issue before? then please let me
know how to go with...
and Isn't there any SIP and ITU-Q.931 interworking standard? any schedule?
if not yet?
but I could only see SIP and QSIG as a draft somewhere in the ietf's.


Thanks for your advice...

Don