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VCS to other VCS

Hello friends,

i have a few questions about my video conference system. My scenario looks like this :


First please i want to know :

1. When i register my Video Phone to the VCS with name for example can i call to other Video Phones registered to other VCS on the internet ? If no what license should i have?

2. When i register a IP phone to the router /it has a PBX/ can i call other IP phones on the internet?

3. What license should i have to increase the limit of the MCU connections from 12  SD to 24 SD chanels for example...

4. What license should i have in the VCS to use it for registering Video Phones on the internet to my VCS without VCS-Expressway

Thanks friends !!!

  • TelePresence
Everyone's tags (3)
VIP Purple

VCS to other VCS

Hello Svetoslav -

I'll try to answer what I can.

  1. Yes you can call external video phones as long as the VCS they are registered to is assessable.  You should be able to call them via IP or domain.  Example: phone@VCS-IP or phone@VCS-Domain.  Note, the other VCS must be confgured with a domain if you want to dial via a URI address with a domain and associated DNS records.
  2. The capacity of the MCU depends on how many media ports you have and the media quality.  There is a chart in the MCU online help that shows the port matrix explaining the quality and capacity for each setting, but without knowing more details of your MCU we can't help much, please let us know more about your MCU such as model and how many media ports you currently have, as well as the current media port quality setting.
  3. You can register devices to the VCS Control as long as it's reachable on the public Internet, ie: having the required ports opened.  We had that exactly configuration setup without issue, before we finally added an Expressway.  If you check in your VCS you can see all the current ports being used under Maintenance > Incoming/Outgoing Ports.  (sorry, I can't remember the location under maintenance specifically, I'm not logged into my VCS to tell you exactly at the moment).

VCS to other VCS

Thanks for the answer my friend. Which are the ports that should be opened to the VCS ? So i can call your video phone for example if i understand you correctly? The MCU is 4501 and i have curently 12 media ports in SD quality. Thanks

VIP Purple

Re: VCS to other VCS

Depending on the version of your VCS, if you've updated to X8.1 yet, you can take a look at the relevant admin guides for the list of ports.

X7.2 Admin Guide, p370 / X8.1 Admin Guide, p388

As long as your VCS is configured with a DNS zone and a search rule point to it, and the endpoint you want to call can be reached by either having a public IP or is behind a VCS, yes you can reach it.

For the MCU, take a look at the MCU 4.2 Admin Guide, p224 for the port matrix chart.  It looks like on your model MCU the max is 12, but there appears to be a media port upgrade option that could double the capacity.  There seems to be several options to double the port capacity for your MCU, take a look at the media port quality and the notes at the bottom of the chart.  Here is the MCU 4501 data sheet, where you can find the part numbers for the two extra capacity options (LIC-4501-PL6 and LIC-4501-MHD).

Re: VCS to other VCS


the VCS in picture here is VCS control !! are you planning to put this on public ip or private ip?