3Com MSR 50 Series Configuration Manual page 1755

mechanisms, including the timer management mechanism, retransmission
mechanism, and slave server mechanism.
structure.
Figure 513 RADIUS packet structure
0 7
Code
Descriptions of fields are as follows:
1 The Code field (1-byte long) is for indicating the type of the RADIUS packet.
Table 53 gives the possible values and their meanings.
Table 53 Main values of the Code field
Code Packet type
1 Access-Request
2 Access-Accept
3 Access-Reject
4 Accounting-Request From the client to the server. A packet of this type carries
5 Accounting-Respon
se
2 The Identifier field (1-byte long) is for matching request packets and response
packets. It varies with the Attribute field and the received valid response packets,
but keeps unchanged during retransmission.
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 the
length are considered the padding and are neglected at receipt. If the length of a
packet is less than that indicated by the Length field, the packet is dropped.
AAA/RADIUS/HWTACACS Configuration Overview
Figure 513
15
Identifier
Authenticator
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, that is, the
authentication succeeds, 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 server rejects the
user and sends an Access-Reject response.
user information for the server to start accounting on the
user. It contains the Acct-Status-Type attribute, which
indicates whether the server is requested to start the
accounting or to end the accounting.
From the server to the client. The server sends to the client a
packet of this type to notify that it has received the
Accounting-Request and has correctly recorded the
accounting information.
shows the RADIUS packet
31
7
Length
1755