We highly recommend consulting an IT or network professional when configuring advanced network settings. If able, the network administrator should always check the IP address, and assign and log any static IP to avoid conflicts in the future.
Switching a phone from DHCP to a static IP can be a useful way to address connectivity issues like URL call is disabled errors. It may also alleviate some, but not all, call quality issues.
If the phone is active on the network and provisioned, best practice is to use the IP address already assigned to it. This should be accessible via the phone's Settings menu (look for the Network Status menu).
This will generally also provide you with the Subnet and Gateway info, which you will need to complete the procedure (otherwise, use ipconfig as described below). If this option is available*, note the current IP address, Subnet, and Gateway, and proceed to set static IP according to the procedure for your phone.
*Aastra IP phone users: Aastra phones will not provide Subnet and Gateway info. Consult the network admin or see below for how to retrieve these addresses.
If the phone is not on the network or otherwise unable to provide valid network info
It is possible to determine an available IP address using ipconfig on a computer within the same subnet as the phone.
First, determine the available IP address range. Be sure that you do not assign an IP address that is already in use on the network, which will cause conflicts. The range of available IP addresses may be determined via the router (consult manufacturer's documentation). Note the range and continue.
To run ipconfig on a Windows PC:
- Click the Start menu.
- In Search/Run bar, type cmd or command, then press Enter. The Command Prompt window will open.
- Alternatively, click Start > All Programs > Accessories > Command Prompt.
- In the Command Prompt, type ipconfig or ipconfig/all, then press Enter. This should return the computer's IP address, Subnet, and Default Gateway info. (If you were not able to obtain Subnet and Gateway info from the phone itself, please note it now.)
- Using the available IP range determined by your router, run a ping command to an address in that range to confirm it is free for use. In the Command Prompt, type: ping [IP address], then press Enter. (Example: ping 192.168.0.200)
- If you get a Reply from message, then that IP address is already in use on the network (and you should not assign it).
- If you get the message Request timed out, then the IP address is available for assignment and you may use it.
Note the IP address you intend to use, along with the Subnet and Gateway, and proceed to set static IP according to the procedure for your phone.