Client; Authentication Process; Port-Based Network Access Control - D-Link DES-3550 Manual

Client

The Client is simply the workstation that wishes to gain access to the LAN or switch services. All workstation must be
running software that is compliant with the 802.1x protocol. For users running Windows XP, that software is included
within the operating system. All other users are required to attain 802.1x client software from an outside source. The Client
will request access to the LAN and or Switch through EAPOL packets and, in turn will respond to requests from the
Switch.

Authentication Process

Utilizing the three components stated above, the 802.1x protocol provides a stable and secure way of authorizing and
authenticating users attempting to access the network. Only EAPOL traffic is allowed to pass through the specified port
before a successful authentication is made. This port is "locked" until the point when a Client with the correct username
and password (and MAC address if 802.1x is enabled by MAC address) is granted access and therefore successfully
"unlocks" the port. Once unlocked, normal traffic is allowed to pass through the port. The D-Link implementation of
802.1x allows network administrators to choose between two types of Access Control used on the Switch, which are:
1. Port-Based Access Control – This method requires only one user to be authenticated per port by a remote RADIUS
server to allow the remaining users on the same port access to the network.
2. MAC-Based Access Control – Using this method, the Switch will automatically learn up to sixteen MAC
addresses by port and set them in a list. Each MAC address must be authenticated by the Switch using a remote
RADIUS server before being allowed access to the Network.

Port-Based Network Access Control

The original intent behind the development of 802.1x was to leverage the characteristics of point-to-point in LANs. Any
single LAN segment in such an infrastructures has no more than two devices attached to it, one of which is a Bridge Port.
The Bridge Port detects events that indicate the attachment of an active device at the remote end of the link, or an active
device becoming inactive. These events can be used to control the authorization state of the Port and initiate the process of
authenticating the attached device if the Port is unauthorized. This is the Port-Based Network Access Control.
DES-3550 Fast Ethernet Layer 2 Switch
Figure 6- 69. Client
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