для Cisco Cisco Packet Data Gateway (PDG)
Evolved Packet Data Gateway Overview
How the ePDG Works ▀
ePDG Administration Guide, StarOS Release 18 ▄
71
Step
Description
13.
On successful authentication, the ePDG establishes the PMIP tunnel towards the P-GW by sending a PBU (Proxy-MIP
Binding Update), which includes the NAI and APN and the Home Network Prefix or IPv4 Home Address option.
Binding Update), which includes the NAI and APN and the Home Network Prefix or IPv4 Home Address option.
14.
The P-GW allocates the requested IP address (IPv4/IPv6 or both) session and responds back to the ePDG with a PBA
(Proxy-MIP Binding Acknowledgement).
(Proxy-MIP Binding Acknowledgement).
15.
The ePDG calculates the AUTH parameter that authenticates the second IKEv2 SA_INIT message.
16.
The ePDG sends the AUTH parameter, the assigned remote IP address in the CP payload, the SAs, and the rest of the
IKEv2 parameters to the UE, and IKEv2 negotiation is complete.
IKEv2 parameters to the UE, and IKEv2 negotiation is complete.
17.
The ePDG sends an IPv6 Router Advertisement to the UE to ensure that the IPv6 stack is fully initialized.
18.
If the ePDG detects that an old IKEv2 SA for the APN already exists, it deletes the IKEv2 SA and sends an
INFORMATIONAL exchange with a DELETE payload to the UE to delete the old IKEv2 SA in the UE as specified in
RFC 4306.
INFORMATIONAL exchange with a DELETE payload to the UE to delete the old IKEv2 SA in the UE as specified in
RFC 4306.
19.
The ePDG session/IPSec SA is fully established and ready for data transfer.
UE-initiated Session Disconnection
The figure below shows the message flow during a UE-initiated session disconnection. The table that follows the figure
describes each step in the message flow.
describes each step in the message flow.
Figure 17. UE-initiated Session Disconnection