Configuring 802.1X

Port-based access control has the effect of creating two types of access on the switch ports. One point of access enables uncontrolled communication, regardless of the authorization state (uncontrolled port). The other point of access authorizes communication between a host and the switch.

The 802.1x is an IEEE standard for port-based network access control. The 802.1x framework enables a device (the supplicant) to request port access from a remote device (authenticator) to which it is connected. Only when the supplicant requesting port access is authenticated and authorized is it permitted to send data to the port. Otherwise, the authenticator discards the supplicant data unless the data is sent to a Guest VLAN and/or non-authenticated VLANs.

Authentication of the supplicant is performed by an external RADIUS server through the authenticator. The authenticator monitors the result of the authentication.

In the 802.1x standard, a device can be a supplicant and an authenticator at a port simultaneously, requesting port access and granting port access. However, this device is only the authenticator, and does not take on the role of a supplicant.

The following varieties of 802.1X exist:

Dynamic VLAN Assignment (DVA)

Dynamic VLAN Assignment (DVA) is also referred to as RADIUS VLAN Assignment in this guide. When a port is in Multiple Session mode and is DVA-enabled, the switch automatically adds the port as an untagged member of the VLAN that is assigned by the RADIUS server during the authentication process. The switch classifies untagged packets to the assigned VLAN if the packets originated from the devices or ports that are authenticated and authorized.

For a device to be authenticated and authorized at a port which is DVA-enabled:

Authentication Methods

The authentication methods can be:

You can configure a port to use 802.1x, MAC-based, or 802.1x and MAC-based authentication. If a port is configured to use both 802.1x and MAC-based authentication, 802.1x supplicant has precedence over non-802.1x device. The 802.1x supplicant preempts an authorized but non-802.1x device at a port that is configured with a single session.

Unauthenticated VLANs and the Guest VLAN

Unauthenticated VLANs and Guest VLAN provide access to services that do not require the subscribing devices or ports to be 802.1x or MAC-Based authenticated and authorized.

An unauthenticated VLAN is a VLAN that allows access by both authorized and unauthorized devices or ports. You can configure one or more VLAN to be an unauthenticated in the Creating VLANs section i. An unauthenticated VLAN has the following characteristics:

The Guest VLAN, if configured, is a static VLAN with the following characteristics.

The switch also uses the Guest VLAN for the authentication process at ports configured with Multiple Session mode and MAC-based authentication. Therefore, you must configure a Guest VLAN before you can use the MAC authentication mode.

802.1X Parameters Workflow

Define the 802.1X parameters as follows:

Note the following: