1 Motorola PMIPv4 Call Flows: Bearer Setup with Dual Anchoring Parviz YeganiVojislav VuceticAlmon Tang (408) (732) (847) GPP2, Calgary, Canada, July 23, 2007 X xxx Calgary, Canada

2 Dual Addresses Concept  The concept of dual IP addresses already exists ( one IP address for local interface and another IP address for home network ) Mobile IPv4 Collocated Care-of Address (CCoA) Mobile IPv6  Disadvantage of CCoA mode is tunneling overhead on the airlink. This overhead can be eliminated using FA CoA mode.  Visited address anchor provides mobility without host mobility management operation  Mobility Management using PMIPv4 defines PMA – Mobility Proxy Agent LMA – Local Mobility Anchor See draft-leung-mip4-proxy-mode-03.txt for details.

3 Dual Anchor Architecture  Client obtains two IP addresses – LoA in visited network Anchored in the LMA Obtained via DHCP or PMIP – HoA in home network Anchored in the HA Obtained via CMIP  Handset policy dictates which address is used by which apps – For SIP-based applications: – LoA for RTP, – HoA for SIP signaling FA HA Home Address Pool Local Address Pool Application Signaling Path and Bearer Path for Relaxed Latency Applications Mobility Control Signaling omitted for clarity Low Latency Bearer Path Home Address (HoA): Assigned by HA Local/Visited Address (LoA): Assigned by LMA PMIP Tunnel srv- AGW anc- AGW MAG/ PMA LMA MIPv4 Tunnel

4 Functional Split  anc-AGW performs the following functions (scenario 3a only): LMA function for PMIPv4 operation FA function for CMIPv4 operation  srv-AGW performs the following functions: Access router for Simple IP service (i.e. no FA service) PMA/MAG functions for PMIP operation  AT has two functions MT provides Simple IP attachment to the CAN TE provides Mobile IP over any access network (HRPD, LTE)

5 PMIPv4 Tunnel Establishment aAGW/ (LMA) HA sAGW/ (MAG) ATH-AAAeBShPCRFV-AAAvPCRF 1. Successful Access Authentication and eBS-sAGW tunnel establishment 2. HAAA assigns HA, VAAA may assign LoA 4. DHCP Discover w/ Rapid Commit (LoA?) 6. DIAMETER Authorization Req 7. DIAMETER Authorization Response 5. PMIP RRQ (NAI, HoA=0,GRE key) 8. Assign LoA from local pool or AAA, Set up forwarding for LoA via PMIP tunnel 9. PMIP RRP (NAI, HoA=LoA, GRE key) 10. Set up forwarding between RAN PMIP session and inter-AGW PMIP tunnel 12. AT obtains the local IP address (i.e. LoA) 3. Apps requests simple IPv4 service 11. DHCP Ack w/ Rapid Commit (LoA) Policy DB

6 CMIPv4 Tunnel Establishment aAGW (LMA/FA) HA sAGW (MAG) ATHAAAeBShPCRFVAAAvPCRF 13. Agent Advertisement (CoA=aAGW, FA challenge disabled) 14. CMIP RRQ (NAI, HoA=0, CoA=aAGW, HA=0, MHAE, MAAE, SrcIP=0, DstIP=aAGW) 15. CMIP RRQ (NAI, HoA=0, CoA=aAGW, HA=HA, MHAE, MAAE, SrcIP=aAGW, DstIP=HA) 21. CMIP RRP (NAI, HoA=HoA, HA=HA, MHAE, SrcIP=HA, DstIP=aAGW) 20. HoA from local pool or AAA; Set up forwarding path for HoA via aAGW-HA tunnel 22. Set up forwarding between aAGW-sAGW tunnel and aAGW-HA tunnel 16. AAA Access-Req (username=NAI) 17. AAA Access-Accept (username=NAI, MN-HA SPI/Key, HoA) 23. CMIP RRP (NAI, HoA=HoA, HA=HA, MHAE, SrcIP=aAGW, DstIP=Bcast) 24. AT obtains HoA via CMIP 18. DIAMETER Authorization Req 19. DIAMETER Authorization Response Policy DB

7 Call Flow – Steps AT performs a successful access authentication. A tunnel is successfully established between eBS and sAGW. 2. During access authetication the HAAA assigns the HA address for the AT. VAAA may also assign the LoA in this step. 3. AT’s application requests for simple IPv4 address. 4. AT broadcasts a DHCPDISCOVER message with the Rapid Commit option to the eBS. The message is sent to the sAGW through the tunnel between the eBS and the sAGW. AT uses the DHCPv4 Rapid Commit option [RFC4039] in order to obtain an IPv4 address and configuration information using a 2-message exchange rather than the usual 4-message exchange. 5. sAGW/MAG assigns a unique GRE Key (used for traffic between MAG and LMA) for the AT and sends a Registration Request to the aAGW/LMA. The message contains NAI, CoA=sAGW, HA=aAGW, GRE Key, HoA=LoA. The MN-HA Authentication Extension contains the SPI and authenticator value derived from MN-HA Key. The message’s source IP address and destination IP address are sAGW and aAGW, respectively. 6. aAGW/LMA authenticates the Registration Request and stores values for assigned LoA and aAGW/LMA in the mobility binding entry. aAGW sends a DIAMETER Authorization Request to the vPCRF, which relays to the hPCRF. hPCRF contacts the policy data base for AT’s policy profile. 7. Policy data base sends the AT’s profile to the hPCRF. hPCRF sends DIAMETER Authorization Response with the AT’s subscription policy to the vPCRF, which may add its own policy before relaying to the aAGW/LMA. 8. A Local Address (LoA) is assigned from a pool (or AAA via PMIP message) and a GRE Key (used for traffic between aAGW/LAM to sAGW/MAG) is assigned for the AT. The mobility binding entry is created for the AT using its NAI. 9. aAGW/LMA returns a PMIP RRP to the sAGW/MAG containing the LoA and the GRE key. 10. A tunnel interface between sAGW and aAGW is configured with Foreign Agent service. A host route is injected into the routing table, which sets up forwarding of packets to the Local Address (LoA) via the GRE tunnel interface. 11. The sAGW sends a DHCPACK message with the Rapid Commit option to the AT through the eBS-sAGW tunnel. 12. AT learns the LoA via DHCP. This LoA is anchored in the aAGW/LMA.

8 Call Flow – Steps FA sends Agent Advertisement (upon arrival of Agent Solicitation) on tunnel interface. The message contains CoA=aAGW, Registration Lifetime, etc. Note that FA challenge procedure is disabled. The source IP address = aAGW and destination IP address = link local multicast, broadcast, or LoA. The tunnel header has IP header with source IP address = aAGW and destination IP address = sAGW and GRE Key. The forwarding operation on the sAGW removes the tunnel header and sends the Agent Advertisement on to the relevant layer 2 session. The mapping of L2 session and GRE Key was set up in step # When an Agent Advertisement is received on the AT, the Mobile IP client sends a Registration Request to the LMA/FA. The message contains Home Address = 0, Care-of Address=aAGW/LMA, Home Agent=HAor 0 (dynamic HA assignment), MN-HA Authentication Extension, and MN-AAA Authentication Extension. The forwarding operation on sAGW takes the Registration Request from the L2 session and encapsulates it with the tunnel header. 15.aAGW performs Foreign Agent function and processes the Registration Request received on the tunnel interface. aAGW relays the message to the HA (which is identified in the HA field or downloaded from the HAAA server. The message’s source IP address and destination IP address are aAGW and HA, respectively. 16.HA performs Home Agent function and processes the Registration Request. The MN-AAA Authentication Extension requires HA to send a AAA Access-Request to the HAAA server to authenticate the AT. 17.After HAAA server authenticates the AT, it sends AAA Access-Accept to the AAA client, HA. The message contains the authorization attributes for HA service (e.g. MN-HA security association). 18.HA authenticates the Registration Request using the MN-HA security association. HA sends a DIAMETER Authorization Request to the hPCRF which contacts the Policy DB for AT’s policy profile. Policy DB sends the AT’s profile to the hPCRF. The hPCRF sends DIAMETER Authorization Response with the AT’s subscription policy to the HA. Included in the message is the S-CSCF address assigned to the AT for SIP service. 20.HA assigns the Home Address from a local address pool or assigned by the HAAA server. The mobility binding entry is created for the AT with NAI in Registration Request. A tunnel interface (either IPinIP or GRE) between aAGW and HA is created. A host route is injected into the routing table, which sets up forwarding of packets to the Home Address (HoA) via the tunnel interface. 21.HA sends a Registration Reply to the FA. The message contains NAI, HA=HA, assigned HoA, assigned S-CSCF, etc. The MN-HA Authentication Extension protects the message. The message’s source IP address and destination IP address are HA and aAGW, respectively.

9 Call Flows - Steps 22 to aAGW creates a tunnel interface between itself and HA upon reception of a successful Registration Reply. The forwarding is set up to forward packets between the tunnel to sAGW and tunnel to HA. 23.aAGW relays the Registration Reply to the AT. The message’s source IP address and destination IP address are aAGW and broadcast, respectively. This message is encapsulated to the sAGW. The forwarding operation on the sAGW removes the tunnel header and sends the Registration Reply on to the relevant L2 session (I.e., over the GRE tunnel established between eBS and sAGW). 24.The Mobile IP client on the AT obtains the Home Address at the completion of the CMIPv4 registration procedure. The AT also obtains the address of the application manager assigned to it.