3Com WX3000 Radius message format, Code Message type Message description, Direction client-server

2)The RADIUS client receives the user name and password, and then sends an authentication request (Access-Request) to the RADIUS server.

3)The RADIUS server compares the received user information with that in the Users database to authenticate the user. If the authentication succeeds, the RADIUS server sends back to the RADIUS client an authentication response (Access-Accept), which contains the user’s authorization information. If the authentication fails, the server returns an Access-Reject response.

4)The RADIUS client accepts or denies the user depending on the received authentication result. If it accepts the user, the RADIUS client sends a start-accounting request (Accounting-Request, with the Status-Type attribute value = start) to the RADIUS server.

5)The RADIUS server returns a start-accounting response (Accounting-Response).

6)The user starts to access network resources.

7)The RADIUS client sends a stop-accounting request (Accounting-Request, with the Status-Type attribute value = stop) to the RADIUS server.

8)The RADIUS server returns a stop-accounting response (Accounting-Response).

9)The access to network resources is ended.

RADIUS message format

RADIUS messages are transported over UDP, which does not guarantee reliable delivery of messages between RADIUS server and client. As a remedy, RADIUS adopts the following mechanisms: timer management, retransmission, and backup server. Figure 1-3 depicts the format of RADIUS messages.

Figure 1-3RADIUS message format

0	7	15	31
	Code	Identifier	7
			Length

Authenticator

Attribute

1)The Code field (one byte) decides the type of RADIUS message, as shown in Table 1-1.

Table 1-1Description on the major values of the Code field

Code	Message type	Message description
		Direction: client->server.
		The client transmits this message to the server to determine if the
1	Access-Request	user can access the network.
		This message carries user information. It must contain the
		User-Name attribute and may contain the following attributes:
		NAS-IP-Address, User-Password and NAS-Port.
		Direction: server->client.
2	Access-Accept	The server transmits this message to the client if all the attribute
		values carried in the Access-Request message are acceptable
		(that is, the user passes the authentication).

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