[cisco-voip] cptone command behavior on certain model routers/hardware

[Erick Bergquist]

Hi,

I have a situation where the impedance command is
being removed off voice-port configuration when the
MGCP cfg changes and the gateway MGCP config is
updated. 

This doesn't effect all gateways/routers though, and
appears to effect the ISR models (2800/3800) and XM
series gateways. This is not happening on 1760, 3700
series, 2620, etc. 

MGCP pushes down cptone command (locale on call
manager side) and on the ISRs and XM, when 'cptone us'
is entered it also changes impedance to 600real. Just
on some routers though, not all. The problem is I have
client who has analog lines where 600Real is not the
best match and cause voice quality issues, and the
best match/sounding impedance is complex1. 

Now, I can remove the ccm-manager config command as a
workaround, but that also means the call manager isn't
in full control of the gateway which could be a
problem at times. We could also change the locale on
the call manager side GW config to one where cptone
sets impedance to complex1 but that causes other
problems with the way the line works and tones heard. 

Does anyone know if cptone command is suppose to
change impedance on some model hardware, or not? I've
been looking all over cisco and not able to find
anything yet. 

Output from a 2610XM or 2801:

router(config-voiceport)#cptone US
%Impedance also changed to 600Real

On 3700 series, 1760:

router(config-voiceport)#impedance complex2
router(config-voiceport)#cptone NO
router(config-voiceport)#Cptone VE
router(config-voiceport)#do show run | inc imped
 impedance complex2
router(config-voiceport)#cptone US
router(config-voiceport)#no impeda

If I do this on router only, with no changes made on
CCM side, it will download new MGCP config and wipe
out the impedance commands on effected models/hardware
only.

ccm-manager config-download reset-xml-version
ccm-manager config-download check-config reset (or
restart)

If I just do a ccm-manager config-download
check-config reset without making changes or clearing
XML version, the commands do not get removed. Only
when there is a difference. I think also on reboot but
have not verified that yet.



		
__________________________________ 
Yahoo! Mail - PC Magazine Editors' Choice 2005 
http://mail.yahoo.com