Figure 1-3 EAPOL frame format
PAE Ethernet type: Protocol type. It takes the value 0x888E.
Protocol version: Version of the EAPOL protocol supported by the EAPOL frame sender.
Type: Type of the EAPOL frame.
Table 1-1 Types of EAPOL frames
EAP-Packet (a value of 0x00)
EAPOL-Start (a value of 0x01)
EAPOL-Logoff (a value of 0x02)
Length: Length of the data, that is, length of the Packet body field, in bytes. If the value of this field
is 0, no subsequent data field is present.
Packet body: Content of the packet. The format of this field varies with the value of the Type field.
EAP Packet Format
An EAPOL frame of the type of EAP-Packet carries an EAP packet in its Packet body field. The format
of the EAP packet is shown in
Figure 1-4 EAP packet format
Code: Type of the EAP packet, which can be Request, Response, Success, or Failure.
Identifier: Allows matching of responses with requests.
Length: Length of the EAP packet, including the Code, Identifier, Length, and Data fields, in bytes.
Data: Content of the EAP packet. This field is zero or more bytes and its format is determined by
the Code field.
lists the types that the device currently supports.
Frame for carrying authentication information, present between a
device and the authentication server.
A frame of this type is repackaged and transferred by RADIUS to get
through complex networks to reach the authentication server.
Frame for initiating authentication, present between a client and a
Frame for logoff request, present between a client and a device.