Jump to content
Vodia PBX forum

Grandstream 2120 - issues with SIP over TCP?

Recommended Posts

Hi folks,


Anyone seen any issues with the default configuration for the grandstream phones and the GXP2120? For the life of me, I couldn't get it working yesterday. Finally changed the signaling to SIP instead of TCP and all of a sudden it started working. Had another GXP phone - GXP 2100 - on the same network and it worked without a hitch. I updated firmware and everything - would not work.


Anyone else seen issues with the 2120?

Share this post

Link to post
Share on other sites

This can depend on the firewall settings, if there is a firewall involved. TCP has the advantage compared to UDP that it transports messages reliably, even if the packet size gets bigger than 1492 bytes. Especially when the SIP INVITE packets get larger (e.g. a lot of codecs to offer, long names) UDP becomes unusable and this is very hard to track down. Imagine a world where email messages would be sent over UDP.

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now