When using Internet telephony, the following issues may occur. Most issues can be resolved quickly and easily.

The following errors are not always reproducible and they do not often appear within in a short time. Often it takes hours or days for an issue to appear. SIP devices are often not always the root cause, but in most cases its the interplay between firewall / router, telephone and the telephony service.

Typical "Voice over IP" issues include:

• The phone does not log on (register) or it logs off repeatedl
• No incoming calls
• You can't hear the remote party, but he receives the ring signal
• The call hangs up after a few seconds
• The call ends after 45-60 seconds
• The callee reveives a ringtone even though you already have hung up
• You can dial a phone number but you can't hear a dialing tone

In recent years, router manufacturers have greatly adapted their devices to the requirements of VoIP applications. To get your router up to date with a firmware update is often sufficient to resolve most issues. Find out more about available firmware updates by proceeding to the website of the manufacturer of your router.

If you still experience connecting issues with your the phone, please check the port settings of your router.

TIP for a quick test: If possible, deactivate your firewall and port forwarding functionality for a short time on your router to check if your phone connects successfully. Then other root causes can be excluded.

STUN: Is an important menu item in the Ninja setting dialog and is located under "Network settings" -> STUN. This feature is often required to help your router to map the correct IP address and ports. Some PBXs cannot function without STUN! If you don't have a STUN server, you can e.g. use globaliptel.mystun.net. Even if your SIP Provider has their own STUN server, it's absolutely ok if you configure some other STUN server as they all feature the very same functionality!

Ninja uses the default values as follows:

Port: 5060 / UDP (SIP logon)
Port: 8000 / UDP (RTP, voice)
Port: 60000 / UDP (RTP, video)
Port: 3478 / UDP (STUN)

In the settings menu item "Network setting" you are able to activate static ports. Normally all ports are negotiated automatically with the SIP provider. The required ports can vary between SIP services. Please check whether specific ports are required by your provider.

It is further necessary to setup the router to forward all required ports to the IP address of the computer on which you're running the Ninja softclient. You will find more details in the user manual of your router.