Handover Keying (hokey) ----------------------- Charter Last Modified: 2011-03-31 Current Status: Active Working Group Chair(s): Glen Zorn Tina Tsou (Ting ZOU) Security Area Director(s): Stephen Farrell Sean Turner Security Area Advisor: Stephen Farrell Mailing Lists: General Discussion:hokey@ietf.org To Subscribe: https://www.ietf.org/mailman/listinfo/hokey Archive: http://www.ietf.org/mail-archive/web/hokey/current/maillist.html Description of Working Group: A mobile device has to re-authenticate each time it changes its point of attachment to the network. When it goes through the full procedure of authentication it creates a series of ruptures, during which the medium cannot flow. This results in a poor user experience during handover. However, it is possible to shorten the time it takes to re-authenticate by reusing the key information developed during the initial authentication. The Handover Keying Working Group is concerned with developing procedures for key reuse and delivery, while respecting good security practice. The Handover Keying Working Group has already done work on this subject, but it has not yet developed the complete set of procedures, protocols, and changes needed for different security environment scenarios and situations. The solutions specified by the HOKEY WG fall into several categories, based on timing and mechanism. The authentication and key management may occur before handoff, when latency is much less critical. Alternatively, authentication and key management can occur as part of the handoff, where latency is critical. Solutions should reduce or eliminate the number of referrals to AAA servers, and solutions should avoid re-executing lengthy EAP method exchanges. This may be accomplished by providing new mechanisms for cryptographic keying material in combination with a protocol for the timely delivery of appropriate keys to the appropriate entities. Solutions are expected to include "handover keying," "low-latency re-authentication," and "pre-authentication" or "early authentication". All solution categories are useful, each supporting different scenarios. The HOKEY WG may provide multiple solutions, each addressing a different scenario. Solutions specified by the HOKEY WG must: 1) Be responsive to handover and re-authentication latency performance objectives within a mobile wireless access network. 2) Fulfill the requirements in RFC 4962 and RFC 5247. 3) Be independent of the access-technology. Any key hierarchy topology or protocol defined must be independent of EAP lower layers. The protocols may require additional support from the EAP lower layers that use it. 4) Accommodate inter-technology heterogeneous handover and roaming. 5) Not require changes to EAP methods. Any extensions defined to EAP must not cause changes to existing EAP methods. In specifying an access-technology-independent solution, media independent guidelines for SDOs may also be needed to explain how the keying material and signaling can be employed in a specific access technology. HOKEY WG Deliverables ===================== 1) A specification of Local Domain Name Discovery for ERP. Currently the use of DHCP mechanisms to request the local domain name is unspecified. There are other useful scenarios that need to be addressed. Lower layer announcement for local domain name is unspecified. Ambiguity with using initial full EAP exchange for re-authentication needs to be clarified. Additional re-authentication scenarios, for which there is interest, need to be addressed. 2) A specification of Early Authentication solutions. These include use of EAP to pre-establish authenticated keying material on a target authenticator prior to arrival of the peer. 3) A specification for a Hokey architecture Document. It includes deployment of ERP and EAP early authentication protocol in the mobile environment. There are various useful scenarios that need to be addressed. This specification and the revision of RFC5296 should be conducted in parallel. 4) Assistance to the 802.21a group in specifying the integration of EAP pre-authentication with IEEE 802.21a. The Hokey Working Group shall perform tasks that are complementary to and do not duplicate work being done in IEEE 802.21a. 6) A specification for NAS-Authenticator interaction. NAS interaction can be used to release resources in the old NAS and achieve faster initiation of authentication. Related work in external SDOs on authenticator/NAS interaction for re-authentication may be taken into consideration. 7) A revision of RFC 5296 to eliminate unnecessary references to the home server. 8) Assistance to the radext and dime Working Groups in developing AAA support for handoff keying. Goals and Milestones: Done First draft on EMSK-based Keying Hierarchy Done First draft with a problem statement on EAP re-authentication and key management Done First draft on EAP Re-authentication and Handover Keying Hierarchy Done First draft on EAP Re-authentication Protocol Done First draft on Protocol and Keying Hierarchy for Visited Domain Handovers and Re-authentication Done Submit EMSK-based Keying Hierarchy draft to IESG Done First draft on Handover Key Distribution Protocol Done Submit the problem statement draft to IESG Done Submit EAP Re-authentication and Handover Keying Hierarchy draft to IESG Done Submit EAP Re-authentication Protocol draft to IESG Done First draft on EAP Pre-authentication Specification for inter-technology and inter-domain handoffs Done Submit Protocol and Keying Hierarchy for Visited Domain Handovers and Re-authentication draft to IESG Nov 2009 First draft on Early Authentication solutions Done First draft on Local Domain Name Discovery for ERP Mar 2010 First draft on Hokey architecture Mar 2010 First draft on NAS-Authenticator Interaction Jul 2010 First draft on revision of RFC 5296 Mar 2011 Submit the Local Domain Name Discovery for ERP draft to IESG Mar 2011 Submit the Early Authentication solutions draft to IESG Jul 2011 Submit the NAS-Authenticator Interaction draft to IESG Nov 2011 Submit the Hokey architecture draft to IESG Nov 2011 Submit the revision of RFC 5296 to IESG Mar 2012 Re-charter or shut down WG Internet-Drafts: Posted Revised I-D Title ------ ------- -------------------------------------------- Apr 2010 Apr 2011 The ERP Local Domain Name DHCPv6 Option Apr 2010 Mar 2011 EAP Re-authentication Protocol Extensions for Authenticated Anticipatory Keying (ERP/AAK) Sep 2010 Jul 2011 Handover Keying (HOKEY) Architecture Design Sep 2010 May 2011 EAP Extensions for EAP Re-authentication Protocol (ERP) Request For Comments: RFC Stat Published Title ------- -- ----------- ------------------------------------ RFC5169 I Mar 2008 Handover Key Management and Re-authentication Problem Statement RFC5295 PS Aug 2008 Specification for the Derivation of Root Keys from an Extended Master Session Key (EMSK) RFC5296 PS Aug 2008 EAP Extensions for EAP Re-authentication Protocol (ERP) RFC5749 PS Mar 2010 Distribution of EAP-Based Keys for Handover and Re-Authentication RFC5836 I Apr 2010 Extensible Authentication Protocol (EAP) Early Authentication Problem Statement