Gamma Horizon Work From Home Settings

The purpose of this document is to offer guidelines to Gamma Horizon End Users on how the LAN & WAN environment should be configured in order to be able to run the Horizon service successfully at a remote/home site.

If an end user wishes to utilise another, non-T2k access solution, they need to ensure that the solution can meet the requirements and functionality set out in this document. Failure to meet these requirements will result in quality and setup/support issues.

Power Supplies

Most Horizon Phones plug directly into your company’s network switch and are powered from that connection. If you are taking your phone home, you will need to make sure you have a Power Supply otherwise your phone will not connect.


On many business and home class routers Active SIP ALG will cause a mixture of problems by adjusting or terminating Horizon traffic packets in such a manner that they are corrupted and cause issues with the service, manifesting in a range of intermittent issues such as; one-way audio, dropped calls, problems transferring calls, handset dropping registration and making or receiving internal calls.

SIP ALGs should be disabled on all CPE routers, we will not accept any faults or issues raised against Horizon if a SIP ALG is enabled.

For instructions on disabling this feature please refer to your specific router user guide.

Access Settings

You must ensure that the following IP addresses and ports (both directions) are available and not blocked by firewalls/Routers. If these ports are not opened (i.e. a customer or network firewall is blocking them), or IP addresses allowed, Horizon will not function correctly.

T2K recommends that only trusted IPs are allowed to send and receive traffic via port 5060 and 5080.,,, 80, 443Device provisioning, including soft clients and software downloads