3.1.5.1 Receiving a DHCPOFFER Message
If the DHCPOFFER message from the DHCP server contains a NAP-SoH (section 2.2.1.1) option with length equal to 3 and value equal to the string "NAP", the client MUST set its NAP-Capable Server state to "Yes". In addition, the client MUST send the SoH token in the NAP-SoH option in the DHCPREQUEST message as specified in section 2.2.1.1. It MUST also include a NAP-CoID (section 2.2.1.3) option in this message.
The NAP-SoH (section 2.2.1.1) option and NAP-CoID (section 2.2.1.3) option are extracted from the DHCPDISCOVER message packet by calling DhcpExtractVendorSpecificOption ([MS-DHCPE] section 3.1.7.2).
In the DHCPREQUEST packet, the NAP-SoH (section 2.2.1.1) option and NAP-CoID (section 2.2.1.3) option are appended by calling DhcpAppendVendorSpecificOption ([MS-DHCPE] section 3.1.7.1).
Otherwise, the client MUST set its NAP-Capable Server state to "No" and send the DHCPREQUEST message without any of the options defined in this document.