Need assistance with making a Polycom phone work remotely

Discussion in '3CX Phone System - General' started by dbarney, Jul 21, 2008.

Thread Status:
Not open for further replies.
  1. dbarney

    Joined:
    May 14, 2008
    Messages:
    18
    Likes Received:
    0
    Hello,

    I have successfully configured both the VOIP Client, and a Polycom phone to work in our internal network. We have about 15 external IP's, so I moved the 3cx system to a seperate IP and firewall. I opened the necessary ports in the firewall, and can successfully make calls from the VOIP client provided by 3CX. But for unknown reasons, I cannot get the Polycom to work remotely. All the settings have been updated, to the new public IP, but still does not work.

    Any suggestions? I am using a Netgear ProSafe FVX538.

    Thanks.
     
  2. Anonymous

    Anonymous Guest

    Have you set a tunnel on the voip client, and then point the Polycom's outbound proxy to the IP of the machine with the VoIP client?

    This is our most successful setup so far.

    Thanks,
     
  3. dbarney

    Joined:
    May 14, 2008
    Messages:
    18
    Likes Received:
    0
    My company cannot use it with that condition. Nor can I resell it to our clients, and we have a lot who want us to build them a VOIP system. So that is unacceptable for us.
     
  4. moon1234

    Joined:
    Jan 25, 2008
    Messages:
    24
    Likes Received:
    0
    The problem with Polycom's is that they do not have any support for STUN. If the remote phones will be connected to the public IP of the 3CX server then you will need to do several things in order for the remote Polycom to work properly.

    - Enter the public IP that the REMOTE phone will be using into the NETWORK>NAT>IP Address field. If the Polycom will be at an employees home then this is really a no go unless the employee works in the IT Department. The reason is very few people have static IP's at home. If the public IP address changes and the Polycom is not updated then when a person places a call they will not hear any audio from the other party. They will also not be able to receive any calls as attempts to contact to the Polycom will go to the old IP address programmed into the NAT IP ADDRESS field.

    - You will need to make sure each Polycom, if there is more than one, at the remote site has a unique SIP signaling port otherwise each Polycom will need it's own public IP address. Depending on your firewall's support for SIP and RTP you may need to manually define the RTP port range that they Polycom uses along with setting up a trigger on the firewall that opens the range of RTP ports that 3cx uses for outbound calling. Since each firewall manufacturer has their own names for such processes I will leave it up to you to enable that.

    - The re-register internal on the Polycom needs to be set to 60 seconds or less. If it is longer, most firewalls will close the inactive port translation on the firewall. A work around is to statically map the SIP signaling port on the firewall to the Polycom. You would need to do this for each Polycom. If you have an option, go with the re-register every 60 seconds. As long as it is a small number of phones it should be fine.

    - The Polycom's will need to be pre-provisioned or you will need to setup an FTP, TFTP or HTTP server for the phones to contact and download thier config files, ring tones, etc. This is a good idea as the Polycom's have a tendency to loose thier minds if they are repeatdly unplugged, rebooted, etc.

    Once you have all of that setup and the phones working, then you need to think about whether you are comfortable sending clear text SIP signaling, Unencrypted RTP traffic and unencrypted config files over the internet. The Polycom's have support for SIPS, SRTP and using a secure server for config files. 3CX supports none of these at the moment.

    If you will be configuring a small remote office you will be much better off to setup an IPSec VPN with several cisco PIX or ASA devices. You then don't need to worry about any of the above. The other route is setting up a Session Border Controller and use it as the external proxy server. This device will be able to discren the public IP and ports being used by the remote Polycom(s). It will then modify the SIP and RTP packets with the correct public IP and Port information before the information is sent to the 3CX server. This is an extra amount of money for hardware or time in setting up an open source version.

    In conclusion, it can be done, but it is a pain. I have a Polycom at home and luckily my cable modem IP changes very infrequently. You will LOVE the sound you get from Polycom's. They are far and away the best sounding physical handsets you can get.
     
Thread Status:
Not open for further replies.