Do I Need a VCM to run IP sets (46xx) 1

[yancey27]

I have a 406 V2 I think, at least thats whats posted on the unit and I'm trying to get a 4620 set to work on it. I heard I will need a VCM for it to work dose anyone know if thats ture and is there any other hardware that I might need. As you can tell I know very little about this device, I usely deal with norstar so any help would be great.

 

[icmpman]

Hopefully, one of the other experts will add to this. I am trying the same thing, but with a 4620 w/ a 406 on 3.1(29). For ip to non-ip communication, the vcm is definitely needed. I thought for IP-to-IP communications the vcm would not be needed, but the manual reads (see below) that the vcm is not needed after the call setup is made. So it sounds to me as if we need one in any case...but with IP-to-IP it doesn't use one of the channels after the setup is made.

What are Voice Compression Modules (VCM's) for?
VCMs are required to support the following scenarios:
• Usage of Embedded Voicemail on the Small Office Edition (used as a memory boost by compressing the
voice files)
• Internal phone calls between an IP device and a non-IP device
• Analog/digital phones to IP trunks (SIP/H.323) including managed Frame Relay and managed IP VPN
(provides echo cancellation)
• IP phones to ISDN or PSTN trunks (convert IP to TDM and vice-versa)
• Call set up between IP phones (VCM resource will be released after call set up if direct media is used) to
provide dial tone, busy tone etc. Direct media is a VoIP concept within the system that allows direct
connection of the media steam (IP packets containing voice samples of the telephone call) between the
two IP devices on the network.
VCMs are NOT required for:
• Calls between IP phones on the same system after call set-up (“Direct Media”), unless call recording is
enabled

 

[IPOfficeIreland]

yes yes yes!

any tdm to ip - vcm channel needed to set up call and is used for duration of call

ip to ip (any form, sip, h323, ipphone) - uses 1 vcm to set up call but if using same codec at each end (e.g. G711) and direct media enabled, then releases the vcm.

to add, if you are using ip to ip, i have tested and can confirm that ip to ip with no direct media enabled only uses vcm momentarily, then releases. They have to have the same codec though.

You can set up an ip phone without a vcm for testing, and make calls, but no speech.

When you are testing, go to Monitor, enable Development Tracing in System, go to Status and you can view the VCM usage.

 

[icmpman]

TheTaker - I don't mean to digress from original question, but I do have a 4620 that is able to get logged into system with extension #, but as soon as I start dialing a number, it goes to "disconnected". Have you seen this? I do not have a vcm installed yet. yancey may run into this as well...?

 

[big70]

Yep, you can register the 4620 whitout the vcm and can make calls to other IP-Phone,s.

But you can,t have a speechpath if you call a analog or Digital phone and also you can,t dial out with your trunks.

So just by a vcm card

Greets Peter

 

[IPOfficeIreland]

haven't seen disconnected but don't waste your time wondering why it shows that when you haven't got a vcm card.

it 100% needs DSP resources to function. get a vcm and problem will go away. You should expect unusuall random occurences when you don't use the required parts.

hope it helps!