Yealink Forums

Hi folks,

Due to bad routing, or bad routers, it may be difficult to make a registration on a given Local SIP Port defined in the yealink phone, in my case, a T20P, but surely the same for other models to!

So, it will be nice, if the phone was able to try each port in a given range until successfully register!

I think some PC software already do this...

Another alternative is the possibility of given a value equal to '0' for the Local SIP Port! This way the phone would try multiple ports until a successful registration.

Regards,
Rui

PS - Needless to say that as soon as it lose the registration it tries to reconnect in the following ports until success!

Hi Ruiseixas,

Currently Yealink Phone only support the fixed port for registeration. Yealink phone should match the SIP port which predefined by the SIP Server in order to register the account. Thank you for providing this idea so that we can continue imporving our product.

Best Regards

Hi,

Thanks for the answer.

I switch the gateway router and the problem persisted, registration lost after a while, I also try some ports reserved for the VPN protocol, that normally pass through firewalls, with no success:

Because the problem of unstable registration persisted, and because now I'm in Algeria, I start to conclude that maybe the ADSL service has a firewall configuration that blocks ports with traffic similar to SIP! After changing the local SIP port, the registration is immediate and an important detail to support this suspicion, is that registrations with less registration expire time are blocked earlier...

Regards,
Rui

We too have been having this problem for years with hundreds of customers on different ISPs. The only thing I can think is that because we use registration timeout of 120 it will happen more frequently. The response by the administrator mentions that it needs to be the same port that is used by the SIP server, but we are not talking about the proxy port, we are talking about the local listen port, AKA the src port. Currently we randomize the listen port and change it when customers have this problem. This is not a good solution. There should be another option and I have to believe it is already available in the phone, it is just not readily apparent.

Hi Micster,

If you register through TCP or TLS phone will use a random source port.
But to UDP protocol, phone can only use a fixed source port now.

Regards,
James

I think you are looking for

sip.listen_port =