How does PGW assign P-CSCF address for an UE during attach time ? Is there any consideration of UE's current location in the network or something else ? Is there any load balancing for P-CSCF ? If yes, then how it is done ?
In PGW usually multiple P-CSCF would be configured. This can be used for load balancing and for restoration purpose also, like primary and secondary
As per the specifications, the address of P-CSCF will be pre-configured in the UE. Where can we see the details in the handset settings? Is it part of the APN configuration?
During Roaming in Volte/IMS Home Network Proxy-Call Session Control Function (P-CSCF) will be used or visited network ?
I was going through IMS call flow and came to know that an IP sec tunnel is established between UE and P-CSCF . I could not find out reasoning behind it.
Why P-CSCF node can not send message directly to S-CSCF ? What could be the reason behind it ? I observed that S-CSCF node can send SIP messages to P-CSCF directly but why P-CSCF can not do towards the S-CSCF ?
