Technical Summary
The current Extensible Authentication Protocol (EAP) keying framework is
not designed to support re-authentication and handovers. This is often
the cause of unacceptable latency in various delay-sensitive environments
(such as mobile wireless networks). The HOKEY Working Group plans to
address these problems by designing a generic mechanism to reuse derived
EAP keying material for handover. This document describes the Handover
Keying (HOKEY) problem statement.
Working Group Summary
This document is a product of the hokey working group, and represents
rough consensus of the working group.
Protocol Quality
This document has been reviewed extensively and the Document Shepherd
believes it to be of high quality. This document was reviewed for the
IESG by Tim Polk.
Note to RFC Editor
Please replace Section 6.2 with the following text:
6.2. IEEE 802.11r Applicability
One of the EAP lower layers, IEEE 802.11 [IEEE.802-11R-D9.0], is in
the process of specifying a fast handover mechanism. Access Points
(APs) are grouped into mobility domains. Initial authentication to
any AP in a mobility domain requires execution of EAP, but handover
between APs within the mobility domain does not require the use of
EAP.
Internal to the mobility domain are sets of security associations to
support key transfers between APs. In one model, relatively few
devices, called R0-KHs, act as authenticators. All EAP traffic
traverses an R0-KH, and it derives the initial IEEE 802.11 keys.
It then distribute cryptographically separate keys to APs in the
mobility domain, as necessary, to support the client mobility. For a
deployment with M designated R0-KHs and N APs, this requires M*N
security associations. For small M, this approach scales reasonably.
Another approach allows any AP to act as an R0-KH, necessitating a
full mesh of N2 security associations, which scales poorly.
The model that utilizes designated R0-KHs is architecturally similar
to the fast re-authentication model proposed by HOKEY. HOKEY,
however, allows for handover between authenticators. This would
allow an IEEE 802.11r-enabled peer to handover from one mobility
domain to another without performing an EAP authentication.