Nortel IP phones use the proprietary Unified Networks IP Stimulus (UNISTIM) protocol. Details of the initial implementation and theory of operation of the UNISTIM protocol can be found in Telephony and Data Network Services at a Telephone, US Patent 7068641 filed May 7, 1999 (more readable version, via Google Patents Beta). Additional complementary information can be found in the Canadian Intellectual Property Office 112 page document TELEPHONY AND DATA NETWORK SERVICES AT A TELEPHONE (Canadian Patent CA 2273657), filed June 7, 1999 or the World Intellectual Property Organization 103 page document (WO/2000/069155) TELEPHONY AND DATA NETWORK SERVICES AT A TELEPHONE filed July 3, 2000.

To drive Nortel IP handsets with an Asterisk server you should use chan_unistim. This channel driver strives to transparently integrate UNISTIM IP phones into an Asterisk-converged network without the need for additional hardware or licensing from Nortel.

A standalone UNISTIM server, that provides simple set-to-set networking for testing environments, is available from: http://www.mlkj.net/UNISTIM/ This software requires at least two Nortel phones and a mysql server and does not provide any PSTN or SIP connectivity.

Models:

• i2001
• i2002
• i2004
• i2050 (softphone)

You've probably heard talk from Nortel that they support SIP and H.323. Be aware that this statement applies to their packaged systems, not their IP sets, and then only if the system as a whole has been correctly licensed and configured. It's particularly important to understand that the IP sets themselves only speak UNISTIM, thus at the most basic level you must have purchased at least a UNISTIM Terminal Proxy Server (UTPS) to use Nortel i2001 (et al) IP sets against SIP devices.

If you're already using a larger system, such as a CS1000 (aka. Succession), then the Call Server needs to have an individual license code added for each SIP endpoint it's networking with, as well as specific configuration on the Call Server and Signalling Server components.

So, none of their IP phones are considered open standards compliant until such time as Nortel releases complete documentation for the current implementation of the UNSTIM protocol in the public domain, a-la the SIP RFCs.

For more information on the mechanics of Nortel IP set internetworking, particularly if you're considering purchasing a Nortel IP-based system, see Nortel PDF document 553-3001-213 (Release 3.00) titled IP Peer Networking -Installation and Configuration.

Nortel 1535 videophone claims to be RFC 3261 compliant SIP for both voice and video calls.

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Diagnostics & how to soft reboot a Nortel IP set

All diagnostic functions begin with the 'lead sequence':

• mute key
• up arrow button
• down arrow button
• up arrow button
• down arrow button
• up arrow button
• mute key

Followed immediately by one of the following sequences:

• 0 key - Display Firmware hard version
• 1 key - RAM check
• 2 key - DTIC check
• 3 key - EEPROM check
• 4 key - Xmt, Rcv, Attenuation levels
• 5 key - TCM loop back test, between i2004 and CE equipment
• 6 key - unassigned
• 7 key - Display Firmware hard version
• 8 key - TCM BERT test
• 9 Release - Reset set/power cycle
• * 2 - RUDP on/off check. If RUDP is off, power cycle the set (9 Release).
• * 0 - Display Firmware soft version

So, to soft reset:
mute-up-down-up-down-up-mute-9-rls

It's a lot faster than cycling the power :-)

Note that i2001 phones lack a mute - they use the # key instead.

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See also:

• Asterisk UNISTIM channels
• VOIP Phones
• Asterisk Phones
• Asterisk Nortel
• Unistimpy