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Web and MAC Authentication
How Web and MAC Authentication Operate
The assigned port VLAN remains in place until the session ends. Clients may
be forced to reauthenticate after a fixed period of time (reauth-period) or at
any time during a session (reauthenticate). An implicit logoff period can be set
if there is no activity from the client after a given amount of time (logoff-period).
In addition, a session ends if the link on the port is lost, requiring reauthenti-
cation of all clients. Also, if a client moves from one port to another and client
moves have not been enabled (client-moves) on the ports, the session ends and
the client must reauthenticate for network access. At the end of the session
the port returns to its pre-authentication state. Any changes to the port’s VLAN
memberships made while it is an authorized port take affect at the end of the
session.
A client may not be authenticated due to invalid credentials or a RADIUS
server timeout. The max-retries parameter specifies how many times a client
may enter their credentials before authentication fails. The server-timeout
parameter sets how long the switch waits to receive a response from the
RADIUS server before timing out. The max-requests parameter specifies how
many authentication attempts may result in a RADIUS server timeout before
authentication fails. The switch waits a specified amount of time (quiet-
period) before processing any new authentication requests from the client.
Network administrators may assign unauthenticated clients to a specific
static, untagged VLAN (unauth-vid), to provide access to specific (guest)
network resources. If no VLAN is assigned to unauthenticated clients the port
is blocked and no network access is available. Should another client success-
fully authenticate through that port any unauthenticated clients on the unauth-
vid are dropped from the port.
MAC-based Authentication
When a client connects to a MAC-Auth enabled port traffic is blocked. The
switch immediately submits the client’s MAC address (in the format specified
by the addr-format) as its certification credentials to the RADIUS server for
authentication.
If the client is authenticated and the maximum number of MAC addresses
allowed on the port (addr-limit) has not been reached, the port is assigned to
a static, untagged VLAN for network access.
The assigned VLAN is determined, in order of priority, as follows:
1. If there is a RADIUS-assigned VLAN, then, for the duration of the client
session, the port belongs to this VLAN and temporarily drops all other
VLAN memberships.