Operation Manual – 802.1x 
Quidway S5600 Series Ethernet Switches-Release 1510  Chapter 1  
802.1x Configuration
 
Huawei Technologies Proprietary 
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z  The authenticator system authenticates the supplicant system.  The authenticator 
system is usually an 802.1x-supported network device (such as a Quidway series 
switch). It provides the port (physical or logical) for the supplicant system to 
access the LAN. 
z  The authentication server system is an entity that provides authentication service 
to the authenticator system. Normally in the form of a RADIUS server, the 
authentication server system serves to perform AAA (authentication, authorization, 
and accounting) . It also stores user information, such as user name, password, 
the VLAN a user belongs to, priority, and the ACLs (access control list) applied. 
Following are the four basic concept related with the above three entities, namely the 
PAE, controlled port and uncontrolled port, the valid direction of a controlled port and 
the way a port is controlled. 
I. PAE 
A PAE (port access entity)  is responsible for the implementation of algorithm and 
protocol-related operations in the authentication mechanism. 
The authenticator system PAE authenticates the supplicant systems when they log into 
the LAN and controls the authorizing state (on/off) of the controlled ports according to 
the authentication result.  
The supplicant system PAE responds to the authentication requests received from the 
authenticator system and submits user authentication information to the authenticator 
system. It can also send authentication and disconnection requests to the authenticator 
system PAE. 
II. Controlled port and uncontrolled port 
The Authenticator system provides ports for supplicant systems to access a LAN. A 
port of this kind is divided into a controlled port and an uncontrolled port. 
z  The uncontrolled port can always send and receive packets. It mainly serves to 
forward EAPoL packets to ensure that a supplicant system can send and receive 
authentication requests. 
z  The controlled port can be used to pass service packets when it is in authorized 
state. It is blocked when not in authorized state. In this case, no packets can pass 
through it. 
z  Controlled port and uncontrolled port are two properties of a access port. Packets 
reaching an access port are visible to both the controlled port and uncontrolled 
port of the access port. 
III. The valid direction of a controlled port 
When a controlled port is in unauthorized state, you can configure it to be a 
unidirectional port, which sends packets to supplicant systems only. 
By default, a controlled port is a unidirectional port.