Thanks Ranjit & Paul, Yes, NW can send ‘n’ number of PCSCF addresses,
Yes, agree Ranjit it’s may be not practical but just wanted to understand if that is allowed? Or Nw accepts REG in sequence like Reg to 1 PCSCF Fail/error response from NW Then retry on 2PCSCF address Fail/error response from NW Then retry on 3rd PCSCF address Success from NW So, here UE is Registered success on 3rd PCSCF address. So, my question is it allowed to send Registration request to all received PCSCF at the same time? and assume UE registered on the 1 success response from NW and ignore remaining. I m correlating Registration flow with INVITE forking responses scenario here. Please let me know if it allowed? On Sat, 20 Nov 2021 at 10:44 PM, Ranjit Avasarala <ranjitka...@gmail.com> wrote: > Hi Arun > > I am not sure how you can get more than 1 P-CSCF address(s) as the P-CSCF > address is discovered by UE i.e returned by GGSN. So even if we assume a > scenario where the GGSN returns 5 P-CSCF address, then yes u can send > REGISTER to all of them ( but this is not a practical scenario) > > Then as per the protocol, all 5 P-CSCFs will respond with 401 and the UE > needs to keep track of all 5 401s and send REGISTER with authentication to > all of them. Then if we assume all of them accept then UE is simultaneously > registered with 5 P-CSCFs > > so though theoretically this may seem possible, but should not and will > not occur in a practical scenario > > To understand more about P-CSCF discovery refer to 3GPP TS 34.229 > > Regards > Ranjit > > On Sat, Nov 20, 2021 at 1:00 AM Arun Tagare <arun.taga...@gmail.com> > wrote: > >> Hi Team, >> >> Need some info, can UE be allowed (as per rule) to send SIP REGISTER >> requests to all the received P-CSCF addresses from NW (during attach) ? >> >> For Ex. >> If UE received 5 P-CSCF address during attach >> >> Is it allowed to send REG to address at the same time >> UE REG to P-CSCF-1---> >> UE REG to P-CSCF-2---> >> UE REG to P-CSCF-3---> >> UE REG to P-CSCF-4---> >> UE REG to P-CSCF-5---> >> >> <--- 401 from P-CSCF-2 >> <--- 401 from P-CSCF-3 >> <--- 401 from P-CSCF-5 >> >> UE AUTH-REG to P-CSCF-2---> >> UE AUTH-REG to P-CSCF-3---> >> UE AUTH-REG to P-CSCF-5---> >> >> <-- 200 OK from P-CSCF-5 >> >> So, UE finally connected to P-CSCF-5 >> I know this may increase signalling load on NW, but want to understand is >> this flow allowed as per rules ? Or there are any restrictions please help >> on understanding >> >> >> >> -- >> >> With Regards >> >> Arun A. Tagare >> +91 9449 029729 >> _______________________________________________ >> Sip-implementors mailing list >> Sip-implementors@lists.cs.columbia.edu >> https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors >> > -- With Regards Arun A. Tagare +91 9449 029729 _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
