Configuring Port-Based and Client-Based Access Control (802.1X)

General 802.1X Authenticator Operation

General 802.1X Authenticator Operation

This operation provides security on a direct, point-to-point link between a single client and the switch, where both devices are 802.1X-aware. (If you expect desirable clients that do not have the necessary 802.1X supplicant software, you can provide a path for downloading such software by using the 802.1X Open VLAN mode—refer to “802.1X Open VLAN Mode” on page 8-26.)

Example of the Authentication Process

Suppose that you have configured a port on the switch for 802.1X authentication operation. If you then connect an 802.1X-aware client (supplicant) to the port and attempt to log on:

1.When the switch detects the client on the port, it blocks access to the LAN from that port.

2.The switch responds with an identity request.

3.The client responds with a user name that uniquely defines this request for the client.

4.The switch responds in one of the following ways:

•If 802.1X (port-access) on the switch is configured for RADIUS authentication, the switch then forwards the request to a RADIUS server.

i.The server responds with an access challenge which the switch forwards to the client.

ii.The client then provides identifying credentials (such as a user certificate), which the switch forwards to the RADIUS server.

iii.The RADIUS server then checks the credentials provided by the client.

iv.If the client is successfully authenticated and authorized to con- nect to the network, then the server notifies the switch to allow access to the client. Otherwise, access is denied and the port remains blocked.

•If 802.1X (port-access) on the switch is configured for local authenti- cation, then:

i.The switch compares the client’s credentials with the username and password configured in the switch (Operator or Manager level).

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