How Proxy Call Session Control Function(P-CSCF) works for LTE users ?

Question

For each bearer in volte there are QCI and ARP parameters, for example default bearer qci 9 arp value, qci 5 arp value, qci 1 arp value, and the ARP has the PCI and PVI parameters too.

So in volte network if we need to have a VIP user how will be the mapping between QCI and ARP values?
And this ARP values need to be configured in the Hss for the user and also in the PCRF?

Answer 1

PCSCF is an entry point to receive all the User agent sip request from the LTE UE. There are number of nodes in IMS architecture like I-CSCF and S-CSCF and Application server along with this P-CSCF.

P-CSCF receives request from the UEs and send to I-CSCF. I-CSCF has connection with HSS to get Ue's subscription profile. Based on subscription details of UE, I-CSCF selects S-CSCF and forward the request to that.

There are some messages goes like .

UE -------- Register ------------------------> IMS
UE <----------- 401 Unauthorized ---------- IMS.
UE---------------Register ----------------------> IMS.
UE <------------ 200 OK ----------------------- IMS.