ES4626-SFP Management Guide.pdf

Chapter 23 802.1x Configuration
23.1 Introduction to 802.1x
The 802.1x protocol originates from 802.11 protocol, the wireless LAN protocol of
IEEE, which is designed to provide a solution to doing authentication when users access
a wireless LAN. The LAN defined in IEEE 802 LAN protocol does not provide access
authentication, which means as long as the users can access a LAN controlling
device(such as a LAN Switch), they will be able to get all the devices or resources in the
LAN. There was no looming danger in the environment of LAN in those primary
enterprise networks.
However, along with the boom of applications like mobile office and service
operating networks, the service providers should control and configure the access from
user. The prevailing application of WLAN and LAN access in telecommunication networks,
in particular, make it necessary to control ports in order to implement the user-level
access control. And as a result, IEEE LAN/WAN committee defined a standard, which is
802.1x, to do Port-Based Network Access Control. This standard has been widely used in
wireless LAN and ethernet.
“Port-Based Network Access Control” means to authenticate and control the user
devices on the level of ports of LAN access devices. Only when the user devices
connected to the ports pass the authentication, can they access the resources in the LAN,
otherwise, the resources in the LAN won’t be available.
23.1.1 The Authentication Structure of 802.1x
The system using 802.1x has a typical Client/Server structure, which contains three
entities(as illustrated in the next figure): Supplicant system, Authenticator system, and
Authentication server system.
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