Hello Franz , You may want to look at the ITU recommendations as well , specifically Q.1912.5 sections 7.1.3 and 6.1.3.6 It has detailed tables on this.
For mapping from SIP to ISUP , you can set the screening indicator of the Generic Number parameter to "user provided , not verified" while mapping from the From header, so that the PSTN n/w knows it is not a trusted number. The PAI goes into the ISUP CGPN with the APRI set according to the Privacy header. For mapping from ISUP to SIP the Generic Number is mapped to From and the Isup CGPN to the PAI. The Privacy header is mapped from the APRI on the ISUP side. The SIP UA knows anyways that the From is not a "trusted" header , so based on local policy it may give preference to the PAI. On the PSTN side , again it's a policy decision provisioned on the switch based on the APRI values on which number should be presented ... HTH , Regards , Sayan -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Franz Edler Sent: Tuesday, August 15, 2006 11:49 AM To: 'Paul Kyzivat'; 'Romel Khan' Cc: sip-implementors@cs.columbia.edu Subject: Re: [Sip-implementors] PSTN integration > What is lacking is two different addresses that are trusted - one to > be provided to the UAS and one that is not. In spite of its historical > precedent, the whole concept seems pretty broken to me. I don't know all historical background but these are the facts with ISUP: ISUP offers one 'Calling Party Number' information element, which is screened by the operator and subject to privacy. This parameter is always mapped to P-Asserted-Identity header field in SIP. ISUP supports in addition one or more 'Generic Number' information elements which can be used as an additional calling party number or connected number. This number may be screened or not. If it is available it is mapped to the >From header field. The problem is that if both numbers are available (in case of SIP via P-Asserted-Identity and From header field) there is no rule for the UAs which one to present or both. The same problem you have also with ISDN user equipment. And the user probably does not know what to do if two numbers are presented. I agree the whole concept from ISUP is not very clear to the end-user. Regards Franz _______________________________________________ Sip-implementors mailing list Sip-implementors@cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors The information contained in this electronic message and any attachments to this message are intended for the exclusive use of the addressee(s) and may contain proprietary, confidential or privileged information. If you are not the intended recipient, you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately and destroy all copies of this message and any attachments. WARNING: Computer viruses can be transmitted via email. The recipient should check this email and any attachments for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by this email. www.wipro.com _______________________________________________ Sip-implementors mailing list Sip-implementors@cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
