Radius Authentication And Authorization; How Radius Authentication Works - Lenovo Flex System Fabric CN4093 Application Manual

RADIUS Authentication and Authorization

How RADIUS Authentication Works

1. Remote administrator connects to the switch and provides user name and
2. Using Authentication/Authorization protocol, the switch sends request to
3. Authentication server checks the request against the user ID database.
4. Using RADIUS protocol, the authentication server instructs the switch to grant or
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CN4093 Application Guide for N/OS 8.4
Enterprise NOS 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 2866)
 A centralized server that stores all the user authorization information
A client, in this case, the switch

The CN4093—acting as the RADIUS client—communicates to the RADIUS server
to authenticate and authorize a remote administrator using the protocol definitions
specified in RFC 2138 and 2866. Transactions between the client and the RADIUS
server are authenticated using 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.
password.
authentication server.
deny administrative access.