Is attach possible without PCRF in LTE network?

Question

This regarding the sessions b/w the PGW and PCRF.

Lets say we have 2 default bearers(DEF1, ad DEF2) for UE1, and 2 dediicated bearers for each of these Default bearers. And for UE2 assume 2 def bearers, DEF3, and DEF4.

Now a CCR is sent for initial default bearer DEF1 creation for UE1. Lets say session(session1) is created for this. with CCRequest number=0.
For Ded bearer1 creation, will it use the same session Id ? and increment the CCRNumber ?
What about the UE2?

I am new to Diameter and earlier, these things were internal and didnot need diameter interface. So the questions are arising.

Answer 1

As per my understanding, it is possible to attach a subscriber without PCRF. However, in that case a PGW should be intelligent enough to decide based on the APN and subscriber what kind of policy to apply. Let's say a user is trying to browse an internet APN and operator do not want to put a granular control over the service then he can put a provision in PGW that based on the APN apply already defined policy.
However, in case of IMS APN it is good to have an external PCRF because if the IMS domain and EPC core are from different operator then it will be difficult to derive a mechanism for AF to talk to PGW to apply any policy or creation/ deletion of a bearer.

Regards,
Peeyush Sharma