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Configuring MAC authentication
Overview
MAC authentication controls network access by authenticating source MAC addresses on a port. It does
not require client software. A user does not need to input a username and password for network access.
The device initiates a MAC authentication process when it detects an unknown source MAC address on
a MAC authentication enabled port. If the MAC address passes authentication, the user can access
authorized network resources. If the authentication fails, the device marks the MAC address as a silent
MAC address, drops the packet, and starts a quiet timer. The device drops all subsequent packets from
the MAC address within the quiet time. This quiet mechanism avoids repeated authentication during a
short time.
NOTE:
If the MAC address that has failed authentication is a static MAC address or a MAC address that has
passed any security authentication, the device does not mark the MAC address as a silent address.
User account policies
MAC authentication supports the following user account policies:
•
One MAC-based user account for each user. The access device uses the source MAC addresses in
packets as the usernames and passwords of users for MAC authentication. This policy is suitable for
an insecure environment.
•
One shared user account for all users. You specify one username and password, which are not
necessarily a MAC address, for all MAC authentication users on the access device. This policy is
suitable for a secure environment.
Authentication approaches
You can perform MAC authentication on the access device (local authentication) or through a Remote
Authentication Dial-In User Service (RADIUS) server.
Suppose a source MAC unknown packet arrives at a MAC authentication enabled port.
In the local authentication approach:
•
If MAC-based accounts are used, the access device uses the source MAC address of the packet as
the username and password to search its local account database for a match.
•
If a shared account is used, the access device uses the shared account username and password to
search its local account database for a match.
In the RADIUS authentication approach:
•
If MAC-based accounts are used, the access device sends the source MAC address as the
username and password to the RADIUS server for authentication.
•
If a shared account is used, the access device sends the shared account username and password
to the RADIUS server for authentication.