2.2.6.1 User Class Option Sent by DHCPv4 Client to DHCPv4 Server

DHCPv4 clients MAY<14> send a User Class Option in all DHCPv4 messages sent by the client with any string configured by the administrator or a string from the User Class Data field. DHCPv4 clients support only one User Class option. For semantics of the usage of DHCPv4 user classes, refer to [RFC3004] section 4.


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Option Code

Option Length

User_Class_Data (variable)

...

Option Code (1 byte): Must be 77 (0x4D) to indicate the User Class Option for DHCP.

Option Length (1 byte): Length in octets of the User Class Data field.

User_Class_Data (variable): The following User Class name is predefined in the DHCPv4 server and is sent by the DHCPv4 client in the specified scenario:

Value

Meaning

"RRAS.Microsoft"

This value MUST be used if the DHCPv4 client is sending a User Class Option in a message on a dial-up or VPN network interface. This string is otherwise known as the Default Routing and Remote Access Class.