Nortel Networks NN43001-504 manual Appendix B Troubleshooting Wlan IP Telephony installations

188Appendix B Troubleshooting WLAN IP Telephony installations

Format of the IP Phone 2004 Terminal DHCP Encapsulated Vendor Specific option

The following definition describes the Nortel IP Phone 2004 specific, Encapsulated Vendor Specific option. This option must be encapsulated in a DHCP Vendor Specific option (Refer to RFC 1541 and RFC 1533) and returned by the DHCP server as part of each DHCP OFFER and ACK message for the IP Phone 2004 to accept these messages as valid. The IP Phone 2004 pulls the relevant information out of this option and uses it to configure the primary and (optionally) secondary TPSs. Either this encapsulated option or a similarly encoded site-specific option must be present. Configure the DHCP server to send one or the other—but not both. WinNT implementations must use the Site Specific option. For more information, see "DHCP support for handsets that emulate the IP Phone 2004" (page 187).

The format of the Encapsulated Vendor Specific option field is: Type,

Length, Data.

•Type (1 octet): 5 choices: 0x80, 0x90, 0x9d, 0xbf, 0xfb (128, 144, 157, 191, 251)

With the choice of five types, the IP Phone 2004 can operate in environments where the initial choice is already in use by a different vendor. Select only one Type byte.

•Length (1 octet): variable—depends on message content

•Data (Length octets): ASCII-based—format Nortel-i2004- A,iii.jjj.kkk.lll:ppppp,aaa,rrr;iii.jjj.kkk.lll:pppp,aaa,rrr

—Nortel-i2004-A uniquely identifies this as the Nortel option. Additionally, the -A signifies this version of this specification. For example, future enhancements could use -B.

—ASCII (,)—separates the fields

—ASCII (;)—separates the primary from secondary server info

—ASCII (.)—signals the end of the structure

—iii.jjj.kkk.lll:ppppp—identifies the IP:port for the server (ASCII-encoded decimal)

—aaa—identifies the action for the server (ASCII-encoded decimal, range 0 to 255)

—rrr—identifies the retry count for the server (ASCII-encoded decimal, range 0 to 255)

Nortel Communication Server 1000

WLAN IP Telephony Installation and Commissioning

NN43001-504 01.02 Standard

Release 5.0 15 June 2007

Copyright © 2004-2007, Nortel Networks