HP 5120 EI Switch Series Configuration Manual page 14

Figure 4 RADIUS packet format
0 7
Code
Descriptions of the fields are as follows:
The Code field (1 byte long) indicates the type of the RADIUS packet.
1.
Table 1 Main values of the Code field
Code Packet type
1 Access-Request
2 Access-Accept
3 Access-Reject
4 Accounting-Request
5 Accounting-Response
The Identifier field (1 byte long) is used to match request and response packets and to detect
2.
retransmitted request packets. Request and response packets of the same type have the same
identifier.
The Length field (2 bytes long) indicates the length of the entire packet, including the Code,
3.
Identifier, Length, Authenticator, and Attribute fields. Bytes beyond this length are considered
padding and are neglected upon reception. If the length of a received packet is less than this
length, the packet is dropped. The value of this field is in the range 20 to 4096.
The Authenticator field (16 bytes long) is used to authenticate replies from the RADIUS server and to
4.
encrypt user passwords. There are two types of authenticators: request authenticator and response
authenticator.
15
Identifier
Authenticator (16bytes)
Attribute
Description
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.
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.
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.
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.
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 correctly recorded the accounting
information.
4
31
7
Length