DHCP options 187
DHCP support for handsets that emulate the IP Phone 2004
DHCP support in the IP Phone 2004 terminal requires a Class Identifier option with each DHCP Discovery and Request message. Additionally, the IP Phone 2004 checks for either a Vendor Specific option message with a specific, unique to Nortel IP Phone 2004 encapsulated subtype, or a
The IP Phone 2004 does not accept any Offers or Acks that do not contain all of the following options:
•a Router option
The IP Phone 2004 requires a default router to function.
•a Subnet Mask option
•a Vendor Specific option
OR
a Site Specific option
The initial DHCP implementation required only the Vendor Specific encapsulated suboption. In interop testing with WinNT (up to SR4), it was discovered that WinNT does not properly adhere to RFC 1541. As a result, it is not possible to use this option. The implementation was changed to add support for either Vendor Specific subops or Site Specific options. This new extension is tested and verified to work with WinNT.
The
Format of the IP Phone 2004 Terminal DHCP Class Identifier field
All IP Phone 2004 terminals fill in the Class ID field of the DHCP Discovery and Request messages with
•
•unique to Nortel IP Phone 2004
•
Nortel Communication Server 1000
WLAN IP Telephony Installation and Commissioning
Release 5.0 15 June 2007
