Vendor-specific option (Option 43)

DHCP servers and clients use Option 43 to exchange vendor-specific configuration information.

The DHCP client can obtain the following information through Option 43:

• ACS parameters, including the ACS URL, username, and password.

• Service provider identifier, which is acquired by the CPE from the DHCP server and sent to the ACS for selecting vender-specific configurations and parameters. For more information about CPE and ACS, see Network Management and Monitoring Configuration Guide.

• PXE server address, which is used to obtain the boot file or other control information from the PXE server.

Network configuration parameters are carried in different sub-options of Option 43 as shown in Figure 16.

• Sub-option type—The field value can be 0x01 (ACS parameter sub-option), 0x02 (service provider identifier sub-option), or 0x80 (PXE server address sub-option).

• Sub-option length—Excludes the sub-option type and sub-option length fields.

• Sub-option value—The value format varies by sub-option.

• ACS parameter sub-option value field—Includes the ACS URL, username, and password separated by spaces (hexadecimal number 20) as shown in Figure 17.

  Figure 17: ACS parameter sub-option value field

  

• Service provider identifier sub-option value field—Includes the service provider identifier.

• PXE server address sub-option value field—Includes the PXE server type that can only be 0, the server number that indicates the number of PXE servers contained in the sub-option, and server IP addresses, as shown in Figure 18.

  Figure 18: PXE server address sub-option value field