Hi,

Having some interesting issues with a HP ProCurve 2510 an Apple Mac Power Book running OSX 10.5.2, and MAC-Auth + EAP-Auth on the same wired port.

I know this isn't strictly the list for this as this isn't really RADIUS, but i'm not sure where to post...

Two questions:

   IEE802.1x-2004
       8.1.3 EAPOL-Logoff
When a Supplicant wishes the Authenticator PAE to perform a logoff (i.e., to set the controlled Port state to unauthorized), the Supplicant PAE originates an EAPOL-Logoff message (see 7.5.4) to the Authenticator PAE. As a result, the Authenticator PAE immediately places the controlled Port in the unauthorized state

1) It appears in the spec that there is no requirement or indeed method of the Supplicant PAE of confirming that the EAPOL-Logoff has been honoured. So the supplicant PAE could be in the unauthorised state while the Authenticator could be in the authorised state. Is this an over site of the dot1x spec, or is this meant to be handled at a higher level with EAP ?

---

2) On the termination of an EAP session, VLAN membership is usually altered, either to a MAC-Authorised VID a default unauthorised VID, or the port is blocked. Windows clients are pretty crap in terms of DHCP when this happens, and fail to renew their leases when moving between authorised and unauthorised states. Apple Mac clients however are very good in terms of DHCP dot1x integration. Unfortunately with EAP-Based and MAC-Based authentication transistions, DHCP renewal doesn't appear to work. This is what i've seen from the traces:

FRAME 6436 - TS 212.482482 - Assumed VLAN 603 - Actual VLAN 603 - EAPOL Logoff FRAME 6440 - TS 212.484947 - Assumed VLAN Blocked (transistion) - Actual VLAN 603 - DHCP REQUEST FRAME 6443 - TS 212.487252 - Assumed VLAN Blocked (transistion) - Actual VLAN 603 - DHCP ACK (Answered by server on 603) FRAME 6454 - TS 212.529774 - Assumed VLAN 134 - Actual VLAN 134 - EAP Failure (Seems to denotate MAC Authentication succeeding)

So it appears after the supplicant sends the EAPOL-Logoff, the DHCP client 
attempts to get a lease very quickly; so quickly in fact that the switch hasn't 
altered the state of the port. The result being that the DHCP request is acked 
by the DHCP server on the dot1x authorised VLAN, the VLAN transistion *then* 
occurs, but as the DHCP client has satisfied itself that it has a valid lease 
for the PAE unauthorised state it doesn't renew the lease until it expires...

Should I be shouting at HP to get their switches to register the state change 
faster, or shouting at Apple to make their DHCP timings less agressive ?

Many Thanks,
Arran

--
Arran Cudbard-Bell ([EMAIL PROTECTED])
Authentication, Authorisation and Accounting Officer
Infrastructure Services | ENG1 E1-1-08 University Of Sussex, Brighton
EXT:01273 873900 | INT: 3900

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