[Asterisk-Users] Re: Again: 7920 Cisco IP Phone Skinny & SIP

[Jan Czmok]

Siggi Langauf (langausd at swt.uni-stuttgart.de) wrote:
> Hi Jan,
> 
> first of all: please don't cross-post!
> 
> On Tue, 13 Jan 2004, Jan Czmok wrote:
> 
> [...]
> >  SKINNY OffHookMessage
> >  SKINNY SetSpeakerModeMessage
> >  SKINNY OnHookMessage
> >  SKINNY DisplayPromptStatusMessage
> >  SKINNY DisplayPromptStatusMessage
> >  SKINNY DisplayPromptStatusMessage
> 
> It looks like chan_sccp is doing something at this pont that upsets the
> 7920 so that it tries to fall back to SRST mode, before finally
> re-registering.

Okay, might be a reason. but what i saw on the display was:

-> Registering to Callmanager
-> Registered to Asterisk PBX
-> Call ended.

(without hitting any button).

Since i work at an ISP, i probably could setup CME on one of my boxen
and you might be able to connect to it, so that we have packet traces to
follow up.

> That re-registration is rejected by chan_sccp, though, as
> the old connection is not closed, yet. So the 7920 gives up and tries to
> find another CallManager.

Possible reason, looks like that, however i am surprised why the 7920
reboots instead of just looking for another callmanager.

> Right now, Theo as well as Martin Bene are looking at the packet traces,
> so I'm sure the issue will be located and fixed soon.

i am also looking through various sources. I'd like to have the 7920
running !

> 
> > But if you look at the Support of the 7920 in Callmanager Express, you
> > get a file named "cmterm_7920.3.3-01-02-021.bin" so i was investigating
> > further. so i wrote "cmterm_7920.3.3-01-02-021" in OS7920.TXT and
> > suddenly the Cisco 7920 shows "Upgrading Firmware" :-)
> > Unfortunately for some reason it did not accept the firmware, but it
> > still tries to load it.
> 
> There should also be a digitally signed version of that file
> (cmterm_7920.*.sbn), which the phone probably requires.

nope. no sbn. according to my cisco source the file is not signed.

> 
> > Some additional info:
> > ---------------------
> > The 7920 is requesting cmterm_7920.3.3-01-02-021^J.bin
> > (so with an Ctrl-J in it), so you have to rename the file.
> 
> You'd better remove the trailing Ctrl-J from OS7920.TXT, then (or stop
> using editors that insist on adding one).

i did, i use vi as editor. i was also surprised, but this is coming from
the phone ( i did extensive tethereal and tcpdump watching) :-)

> > I also got the information from documents that the 7920 is running in
> > 7960 emulation mode, so draw your own conclusions in regards of SIP
> > possiblity :-)
> 
> Nope, there is a statement from Cisco that SIP support for the 7920 is not
> planned, ATM.
> "7960 emulation mode" refers only to being compatible with a 7960, as long
> as you do _not_ try to upload any firmware. (ie. Skinny-wise)
> However, that compatibility is not quite 100%...

Yep, right. 

> > I tried to use some 7960 images, but did not succeed :-(
> 
> Of course not, it's totally different hardware.

is it ? the cmterm image is nearly exactly 2 times the 7960 phone, so i
suspect one lower part of the image for the new functions and the rest
for the "normal" 79xx image. 

> 
> > Would appreciate some help in this issue :-)
> 
> Just sit back and wait!

How can i help ? Just sit back isnt appropate for me :-)

> 
> Meanwhile, you can register your 7920 with CallManager Express and connect
> that to asterisk via chan_oh323. (Note: chan_h323 will most likely not
> work, at least if you need two-way audio ;)
> 
Hmm. Might be one way to use CME. Will see..

--jan



-- 
Jan Czmok, Network Engineering & Support, Global Access Telecomm, Inc.
Ph.: +49 69 299896-35 - fax: +49 69 299896-40 - sip:13129*522 at inoc-dba.pch.net