R3204P16-HP Load Balancing Module Security Configuration Guide-6PW101

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RADIUS packet format
RADIUS uses UDP to transmit messages. To ensure smooth message exchange between the RADIUS
server and the client, RADIUS uses a series of mechanisms, including the timer management mechanism,
the retransmission mechanism, and the backup server mechanism. Figure 111 sh
ows the RADIUS packet
format.
Figure 111 RADIUS packet format
Descriptions of the fields are as follows:
1. The Code field (1-byte long) indicates the type of the RADIUS packet. Table 35 gives the possible
values and their meanings.
Table 35 Main values of the Code field
Code Packet t
yp
e Descri
p
tion
1 Access-Request
From the client to the server. A packet of this type carries user
information for the server to authenticate the user. It must contain the
User-Name attribute and can optionally contain the attributes of
NAS-IP-Address, User-Password, and NAS-Port.
2 Access-Accept
From the server to the client. If all the attribute values carried in the
Access-Request are acceptable, the authentication succeeds, and the
server sends an Access-Accept response.
3 Access-Reject
From the server to the client. If any attribute value carried in the
Access-Request is unacceptable, the authentication fails and the server
sends an Access-Reject response.
4 Accounting-Request
From the client to the server. A packet of this type carries user
information for the server to start or stop accounting for the user. The
Acct-Status-Type attribute in the packet indicates whether to start or stop
accounting.
5 Accounting-Response
From the server to the client. The server sends a packet of this type to
notify the client that it has received the Accounting-Request and has
successfully recorded the accounting information.
2. The Identifier field (1 byte long) is used to match request packets and response packets and to
detect duplicate request packets. Request and response packets of the same type have the same
identifier.
3. The Length field (2 byte long) indicates the length of the entire packet, including the Code,
Identifier, Length, Authenticator, and Attribute fields. Bytes beyond this length are considered
Code
Attribute
Identifier
0
7
Length
Authenticator (16bytes)
715 31