SGS-6341-Series User Manual

Figure 42-4: the Format of EAP Data Packets
Code: specifies the type of the EAP packet. There are four of them in total: Request
（1）,Response（2）,Success（3）,Failure（4）.
 There is no Data domain in the packets of which the type is Success or Failure, and the
value of the Length domains in such packets is 4.
 The format of Data domains in the packets of which the type is Request and Response is
illustrated in the next figure. Type is the authentication type of EAP, the content of Type
data depends on the type. For example, when the value of the type is 1, it means Identity,
and is used to query the identity of the other side. When the type is 4, it means
MD5-Challenge, like PPP CHAP protocol, contains query messages.
Figure 42-5: the Format of Data Domain in Request and Response Packets
Identifier: to assist matching the Request and Response messages.
Length: the length of the EAP packet, covering the domains of Code, Identifier, Length and
Data, in byte.
Data: the content of the EAP packet, depending on the Code type.
42.1.4 The Encapsulation of EAP Attributes
RADIUS adds two attribute to support EAP authentication: EAP-Message and
Message-Authenticator. Please refer to the Introduction of RADIUS protocol in
“AAA-RADIUS-HWTACACS operation” to check the format of RADIUS messages.
1. EAP-Message
As illustrated in the next figure, this attribute is used to encapsulate EAP packet, the type code
is 79, String domain should be no longer than 253 bytes. If the data length in an EAP packet is
larger than 253 bytes, the packet can be divided into fragments, which then will be
encapsulated in several EAP-Messages attributes in their original order.
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User’s Manual of SGS-6341 series