Juniper Networks EX2500 User Manual

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Securing Access to the Switch
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11
Chapter 1: Accessing the Switch
RADIUS Authentication and Authorization
The EX2500 switch supports the RADIUS (Remote Authentication Dial-in User 
Service) method 
to 
authenticate and authorize remote administrators for managing 
the switch. This method is based on a client/server model. The Remote Access 
Server (RAS)—the switch—is a client to the back-end database server. A remote 
user (the remote administrator) interacts only with the RAS, not the back-end 
server and database. 
RADIUS authentication consists of the following components:
„
A protocol with a frame format that utilizes UDP over IP (based on RFC 2138 
and RFC 2866)
„
A centralized server that stores all the user authorization information
„
A client, in this case, the switch
The EX2500 switch—acting as the RADIUS client—communicates to the RADIUS 
server to authenticate and authorize a remote administrator using the protocol 
definitions specified in RFCs 2138 and 2866. Transactions between the client and 
the RADIUS server are authenticated by a shared key that is not sent over the 
network. In addition, the remote administrator passwords are sent encrypted 
between the RADIUS client (the switch) and the back-end RADIUS server.
How RADIUS Authentication Works
1.
The remote administrator connects to the switch and provides username and 
password.
2.
Using Authentication/Authorization protocol, the switch sends request to 
authentication server.
3.
The authentication server checks the request against the user ID database.
4.
Using RADIUS protocol, the authentication server instructs the switch to grant 
or deny administrative access.
Configuring RADIUS on the Switch
Use the following procedure to configure RADIUS authentication on your switch: 
1.
Configure the Primary and Secondary RADIUS servers, and enable RADIUS 
authentication. 
ex2500(config)# radius-server primary-host 10.10.1.1
ex2500(config)# radius-server secondary-host 10.10.1.2
ex2500(config)# radius-server enable
2.
Configure the RADIUS secret. 
ex2500(config)# radius-server primary-host 10.10.1.1 key <1-32 character 
secret>
ex2500(config)# radius-server secondary-host 10.10.1.2 key <1-32 character 
secret>