PDN Gateway Overview
▀ How the PDN Gateway Works
▄ Cisco ASR 5x00 Packet Data Network Gateway Administration Guide
92
Step
Description
4
The HSGW begins the tear down of the PMIP session by sending a PBU Deregistration to the P-GW with the following
attributes: Lifetime=0, MNID, APN, ATT=HRPD, HNP. The PBU Deregistration message should contain all the mobility
options that were present in the initial PBU that created the binding.
5
The P-GW looks up the Binding Cache Entry (BCE) based on the HNP, deletes the binding, and responds to the HSGW
with a Deregistration PBA with the same attributes (Lifetime=0, MNID, APN, ATT=HRPD, HNP).
6
The HSGW optionally sends a Router Advertisement (RA) with assigned HNP and prefix lifetime=0.
PDN Connection Release Initiated by HSGW
This section describes the procedure of a session release by the HSGW.
Figure 12.
PDN Connection Release by the HSGW Call Flow
Table 5.
PDN Connection Release by the HSGW Call Flow Description
Step
Description
1
The UE is attached to the EPC and has a PDN connection with the P-GW for PDN-ID=x and APN with assigned HNP.
2
The HSGW MAG service triggers a disconnect of the PDN connection for PDNID=x.
3
The HSGW sends a PPP VSNCP-Term-Req with PDNID=x to the UE.