HP ProCurve 2910al Access Security Manual page 476

Configuring Port-Based and User-Based Access Control (802.1X)
802.1X Open VLAN Mode
802.1X Per-Port Configuration
Open VLAN Mode with Only an Unauthorized-Client VLAN Configured:
12-36
Port Response
• When the port detects a client, it automatically becomes an
untagged member of this VLAN. To limit security risks, the network
services and access available on this VLAN should include only
what a client needs to enable an authentication session. If the port
is statically configured as an untagged member of another VLAN,
the switch temporarily removes the port from membership in this
other VLAN while membership in the Unauthorized-Client VLAN
exists.
• After the client is authenticated, and if the port is statically
configured as an untagged member of another VLAN, the port's
access to this other VLAN is restored.
Note: If RADIUS authentication assigns the port to a VLAN, this
assignment overrides any statically configured, untagged VLAN
membership on the port (while the client is connected).
• If the port is statically configured as a tagged member of a VLAN,
the port returns to tagged membership in this VLAN upon
successful client authentication. This happens even if the RADIUS
server assigns the port to another, authorized VLAN. Note that if
the port is already configured as a tagged member of a VLAN that
RADIUS assigns as an authorized VLAN, then the port becomes
an untagged member of that VLAN for the duration of the client
connection.
Note for a Port Configured To Allow Multiple Client Sessions: If any
previously authenticated clients are using a port assigned to a VLAN
other than the Unauthorized-Client VLAN (such as a RADIUS-
assigned VLAN), then a later client that is not running 802.1X
supplicant software is blocked on the port until all other,
authenticated clients on the port have disconnected. Refer to figure
12-1 on page 12-11.