ES4626-SFP Management Guide.pdf

query messages.
Fig 23-5 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.
23.1.4 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.
Fig 23-6 the Encapsulation of EAP-Message Attribute
2. Message-Authenticator
As illustrated in the next figure, this attribute is used in the process of using
authentication methods like EAP and CHAP to prevent the access request packets from
being eavesdropped. Message-Authenticator should be included in the packets
containing the EAP-Message attribute, or the packet will be dropped as an invalid one.
Fig 23-7 Message-Authenticator Attribute
23.1.5 The Authentication Methods of 802.1x
842