If you want to use an audio codec in your local network, then you have to configure the firewall of your LAN.
Please ask for network adminstrator to set up the following firewall rules:
- Outgoing SIP signaling
Port 5060/UDP, port 5062/UDP, and port 5060/TCP must be opened for outgoing, bidirectional data flows. We use as a SIP server the DNS entry sipcast.net, which points to multiple IP addresses that may change dynamically. Thus, please do not enter an destination IP address into the firewall. - Outgoing STUN signaling
For STUN requests, the port 3478/UDP must be enabled. Please do not enter an IP destination address, either. - RTP data flows to the Sipcast server
Our media server used – most of the time – the UDP ports 30000 till 32000 for incoming RTP data flows. Please open UDP for ports 30000 bis 32000 (both including). - No SIP proxy
Some firewalls and some NAT router have a build SIP proxy or a SIP Application Level Gateway (ALG). These must be disabled. - DNS access
The audio codec muss have access to a DNS service (using port 53/UDP and port 53/TCP). Some firewalls require to enable access to the LAN access in separate settings. - Optional: direct RTP data flows between audio codecs
If you wish to use an transmission mode that allows both audio codec to communicate directly, please open the UDP port range of 1024 till 65535 for both in- and outgoing flows.
All rules above are supposed to for IP version 4. IPv6 must not be enabled.