Operation Manual – 802.1x
Quidway S3100 Series Ethernet Switches
Chapter 1 802.1x Configuration
Huawei Technologies Proprietary
1-1
Chapter 1 802.1x Configuration
1.1 Introduction to 802.1x
The 802.1x protocol (802.1x for short) was developed by IEEE802 LAN/WAN
committee to address security issues of wireless LANs. It was then used in Ethernet as
a common access control mechanism for LAN ports to address mainly authentication
and security problems.
802.1x is a port-based network access control protocol. It authenticates and controls
devices requesting for access in terms of the ports of LAN access control devices. With
the 802.1x protocol employed, a user-side device can access the LAN only when it
passes the authentication. Those failing to pass the authentication are denied when
accessing the LAN, as if they are disconnected from the LAN.
1.1.1 Architecture of 802.1x Authentication
802.1x adopts a client/server architecture with three entities: a supplicant system, an
authenticator system, and an authentication server system, as shown in the following
figure.
Supplicant PAE
Supplicant system
Authentication
server
Authentication
server system
Servic es pr ovided by
authenticat or
Authenticat or PAE
Authenticator system
Port under
control
Port not authorized
Port not
Under
control
LAN/WLAN
Supplicant PAE
Supplicant system
Authentication
server
Authentication
server system
Servic es pr ovided by
authenticat or
Authenticat or PAE
Authenticator system
Controlled port
Port not authorized
Uncontrolled
port
LAN/WLAN
Supplicant PAE
Supplicant system
Authentication
server
Authentication
server system
Servic es pr ovided by
authenticat or
Authenticat or PAE
Authenticator system
Port under
control
Port not authorized
Port not
Under
control
LAN/WLAN
Supplicant PAE
Supplicant system
Authentication
server
Authentication
server system
Servic es pr ovided by
authenticat or
Authenticat or PAE
Authenticator system
Controlled port
Port not authorized
Uncontrolled
port
LAN/WLAN
Figure 1-1
Architecture of 802.1x authentication
z
The supplicant system is an entity residing at one end of the LAN segment and is
authenticated by the authenticator system connected to the other end of the LAN
segment. The supplicant system is usually a user terminal device. An 802.1x
authentication is initiated when a user launches client program on the supplicant
system. Note that the client program must support the EAPoL (extensible
authentication protocol over LANs).