No Inbound Audio on Endpoint (No NAT)

Asterisk Asterisk Endpoints
1

Endpoint is on separate WAN with its own ip Ex: 8.8.8.8
Asterisk is on separate WAN with its own ip Ex: 5.5.5.5

I connect my endpoint fine and setup to test endpoint to hear audio from asterisk server, but I cant hear anything. I can see in asterisk CLI its playing a sound from its original directory but I hear no audio.

I did trial and error on all the settings and find out I needed to add rtp_symmetric=yes
but I want to know why?

The definition below explain what it does but is there a way for me to check where my rtp is being send to and where?

rtp_symmetric
Enforce that RTP must be symmetric. Send RTP back to the same address/port we received it from.

I want to learn more about asterisk and how it all falls together.

2

rtp debug on

at the CLI prompt.

or tcpdump and wireshark

3

Add the following settings to your endpoint

direct_media=no
rtp_symmetric=yes
force_rport=yes
rewrite_contact=yes ; necessary if endpoint does not know/register public ip:port
ice_support=yes ;This is specific to clients that support NAT traversal