Chapter 1 802.1X Configuration; Introduction To 802.1X; Architecture Of 802.1X Authentication - Huawei Quidway S3900 Series Operation Manual

Operation Manual – 802.1x
Quidway S3900 Series Ethernet Switches-Release 1510

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 system Supplicant system Supplicant system Supplicant system
Supplicant PAE Supplicant PAE Supplicant PAE Supplicant PAE
Figure 1-1 Architecture of 802.1x authentication
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).
Authenticator system Authenticator system Authenticator system Authenticator system
Servic es pr ovided by Servic es pr ovided by Servic es pr ovided by Servic es pr ovided by
authenticat or authenticat or authenticat or authenticat or
Port not authorized Port not authorized Port not authorized Port not authorized
Controlled port Controlled port
Port under Port under
control control
LAN/WLAN LAN/WLAN LAN/WLAN LAN/WLAN
Huawei Technologies Proprietary
1-1
Chapter 1 802.1x Configuration
Authenticat or PAE Authenticat or PAE Authenticat or PAE Authenticat or PAE
Port not Port not
Uncontrolled Uncontrolled
Under Under
port port
control control
Authentication Authentication Authentication Authentication
server system server system server system server system
Authentication Authentication Authentication Authentication
server server server server