Reference13r3:IP4/General/STUN

STUN Servers

The default STUN servers that should be used on a box by ICE and SIP, if no configuration is given at the individual registrations. The field must contain a string in the following format:

• up to two STUN servers which shall be queried in parallel, separated by semi-colon (;)

Each STUN server is denoted as

• either a single DNS name and an optional port (e.g. stun.example.com:1234)
• or a comma separated list of one or two IP addresses and optional ports (e.g. 172.16.13.1:1234,172.16.13.2)

<br\> This format is also used for the STUN server configuration in the DHCP innovaphone Vendor Option 219 .

TURN Servers

You can configure up to two TURN server in one of the following formats.

• either a single DNS name and an optional port (e.g. turn.example.com:1234)
• or a comma separated list of one or two IP addresses and optional ports (e.g. 172.16.13.1:1234,172.16.13.2)
• Client Turn failover: If the Turn allocation fails on the first entry the next entry will be used in the next calls and all following calls until this entry fails, then it will switch again to the other entry.

A TURN server configuration can optionally be followed by a protocol specification such as e.g. turn.company.tld?transport=prot where prot can be either tcp or udp.

TURN Username

The user name for communication with the TURN server.

TURN Password

The password for communication with the TURN server.

TURN Extern

This is an additional TURN Server configuration, which is used for external/public users as a fallback if the normal configuration does not work. For external users it usually cannot be controlled that the appropriate ports are opened in the firewall, so this can be used define a port which is most likely open. The TCP port 443 (HTTPS) is a good choice here (e.g. turn.company.tld:443?transport=tcp).

TURN Extern Username

The user name for communication with the TURN server.

TURN Extern Password

The password for communication with the TURN server.

Slow STUN/TURN Server

Increase the default timeout for a established TURN session from 300ms to 1,5 seconds.

NAT Detection

The box can do a NAT detection as described in RFC 3489 and display the determined NAT type. This is done by sending different requests to the configured STUN server.

NAT Detection Interval(mins)

If configured the box will a do a NAT detection every x minutes. Leave empty to turn it off.

Note: This is an administrational debugging tool only. It has no effect on actual phone calls on the device. Keep in mind that the NAT detection creates significant load on the configured STUN server, if it is used on many devices and with short intervals. So the best practice is to configure it only when needed and then turn it off again.