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Mobile IPv6 Bootstrapping Architecture using DHCP draft-ohba-mip6-boot-arch-dhcp-00. Yoshihiro Ohba, Rafael Marin Lopez, Mayumi Yanagiya, Hiroyuki Ohnishi and Kuntal Chowdhury. Mobility Service, Network Access Service and AAA.
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Mobile IPv6 Bootstrapping Architecture using DHCPdraft-ohba-mip6-boot-arch-dhcp-00 Yoshihiro Ohba, Rafael Marin Lopez, Mayumi Yanagiya, Hiroyuki Ohnishi and Kuntal Chowdhury 61st IETF MIP6 WG
Mobility Service, Network Access Service and AAA • Integration of a bootstrapping architecture with AAA infrastructure is needed • Operators rely on AAA protocol to provide authentication, authorization and accounting functionalities for their subscribers of services • The services include network access service and mobility service • In many cases, AAA for network access (AAA-NA) occurs before AAA for mobility service (AAA-MS) • It is reasonable to consider a scenario where there is some dependency between AAA-NA and AAA-MS 61st IETF MIP6 WG
Two Minimum Sets of Seed Information • Parameter Set 1: • The domain name or FQDN of the home agent • IKE credentials • Parameter Set 2: • Network access credentials • draft-ohba-mip6-boot-arch uses Parameter Set 2 61st IETF MIP6 WG
Basic Architecture Serving or Home MSP ASP or IASP AAA-NA Server AAA protocol AAA-MS Server AAA protocol protocol DHCP Server AAA protocol AAA protocol Serving or Home MSP protocol Network access authentication protocol Home Agent NAS Mobile Node/ DHCP Client DHCPv6 61st IETF MIP6 WG
Basic Architecture (cont’d) • DHCP server in the visited network is used for delivering bootstrap information to MN • The visited network may be the home network • DHCP delayed authentication is used for integrity protected delivery of bootstrap information • DHCP delayed authentication key is also bootstrapped from AAA-NA • Alper’s comment: DHCP authentication problem can be separated • NAS and/or DHCP server in the visited network is aware of MIPv6 service (but they do not need to speak MIPv6) • Two models exist depending on who is AAA-MS client • Model 1: DHCP server as AAA-MS client • DHCP server directly communicates with AAA-MS server to obtain MIP6 bootstrap information • Model 2: NAS as AAA-MS client • NAS communicates with AAA-MS server to obtain MIP6 bootstrap information • NAS passes the obtained bootstrap information to DHCP server 61st IETF MIP6 WG
Model 1(DHCP Server as AAA-MS Client) (1)Network Access Authentication Protocol Client (1’)AAA-NA Network Access Client NAS AAA-Key (2) DHCPv6 with Delayed Authentication DHCP Key AAA Infrastructure (2)AAA-MS DHCP Server DHCP Client MIP6 bootinfo {HA [,HoA or HoL], DHCP-key} MIP6 bootinfo {HA [,HoA or HoL]} (2)AAA-MS Mobile Node Home Agent (3)IKE MIP6 bootinfo {IKE credentials [,HoA or HoL]} MIP6 bootinfo {[HoA or HoL]} 61st IETF MIP6 WG
Model 2(NAS as AAA-MS Client) (1)Network Access Authentication Protocol (1’)AAA-NA (2)AAA-MS Client MIP6 bootinfo {HA [,HoA or HoL], AAA-Key [,DHCP-key]} Network Access Client NAS MIP6 bootinfo {HA [,HoA or HoL] [,DHCP-key]} (2’) DHCPv6 with Delayed Authentication DHCP Key AAA Infrastructure DHCP Server DHCP Client MIP6 bootinfo {HA [,HoA or HoL]} (2)AAA-MS Mobile Node Home Agent (3)IKE MIP6 bootinfo {IKE credentials [,HoA or HoL]} MIP6 bootinfo {[HoA or HoL]} 61st IETF MIP6 WG
Mapping to Bootstrapping Scenarios • Bootstrapping problem statement draft identifies four cases • Mobility Service Subscription Scenario • Integrated ASP (IASP) Scenario • Third-party MSP Scenario • Infrastructure-less Scenario • Some scenarios do not assume relationship between AAA-NA and AAA-MS • Mobility service subscription scenario and infrastructure-less scenario are not supported in this bootstrapping architecture • This architecture is intended for IASP scenario and third-party ASP scenario 61st IETF MIP6 WG
Integrated ASP Scenario (Model 1) IASP (ASP+MSP) NAS/ DHCP Server Mobile Node AAA-NA Server Home Agent AAA-MS Server NA Req. AAA-NA Authentication Authorization for NA AAA-NA NA Rep. DHCP Req. Parameter Req. Authorization for MS IKE credentials DHCP Rep. Parameter Req. IKEv2 IKEv2 61st IETF MIP6 WG
Integrated ASP Scenario (Model 2) IASP (ASP+MSP) NAS/ DHCP Server Mobile Node AAA-NA Server Home Agent AAA-MS Server NA Req. AAA-NA Authentication Authorization for NA Parameter Req. Authorization for MS IKE credentials Parameter Rep. AAA-NA NA Rep. DHCP Req. DHCP Rep. IKEv2 IKEv2 61st IETF MIP6 WG
Third-Party MSP Scenario (Model 1) Home MSP is integrated with ASP, OR Home MSP has roaming agreement with ASP ASP Serving MSP Home MSP NAS/ DHCP Server Mobile Node AAA-NA Server Home Agent AAA-MS Server NA Req. AAA-NA Authentication Authorization for NA NA Rep. AAA-NA DHCP Req. Parameter Req. Authorization for MS IKE credentials DHCP Rep. Parameter Req. IKEv2 IKEv2 61st IETF MIP6 WG
Third-Party MSP Scenario (Model 2) Home MSP is integrated with ASP, OR Home MSP has roaming agreement with ASP ASP Serving MSP Home MSP NAS/ DHCP Server Mobile Node AAA-NA Server Home Agent AAA-MS Server NA Req. AAA-NA Authentication Authorization for NA Parameter Req. Authorization for MS IKE credentials NA Rep. Parameter Rep. AAA-NA DHCP Req. DHCP Rep. IKEv2 IKEv2 61st IETF MIP6 WG
Other Bootstrapping Architectures(draft-yegin-mip6-aaa-fwk) • Uses home agent as AAA-MS client • Assumption: HA address is somehow known to MN (e.g., pre-configuration, DNS SRV record) • Simplest but operators want to provide flexibility in assignment of HA address • E.g., assigning different HA depending on the profile of subscriber 61st IETF MIP6 WG
Other Bootstrapping Architectures(draft-giaretta-mip6-authorization-eap) • Uses EAP for conveying bootstrapping information between MN (EAP peer) and AAA-NA server (EAP server) • The bootstrapping procedure is transparent to access network • Potential complexity for multiple-domain case 61st IETF MIP6 WG
Security Considerations • Question: Is it valid to use DHCP in ASP to deliver HA assigned by MSP? • If the ASP and MSP are separated, the MSP might not want to expose bootstrapping information to other providers • Answer: The bootstrapping information can be encrypted based on SA between MN and AAA-MS server • The DHCP server can deliver the encrypted information to mobile as opaque data if such an option is defined 61st IETF MIP6 WG
Open Issues • When multiple MSPs are able to assign HA to MN, how to determine which MSP should be the assigner(s)? • This case could happen in a hybrid case of IASP scenario and third-party scenario (i.e., AAA-MS servers exist in both ASP and home MSP) • Model 1 might have some security issue • If there is no coordination between AAA-MS client (DHCP server) and AAA-NA client (NAS), AAA-MS procedure is performed without authentication • A DHCP server would initiate AAA-MS without making sure whether the requesting MN has been authorized by the NAS in the AAA-NA procedure 61st IETF MIP6 WG
Next Step • If the architecture is relevant, make it part of the entire bootstrapping architecture • This architecture is NOT the only solution • Resolve the open issues 61st IETF MIP6 WG
Thank you! 61st IETF MIP6 WG