PJSIP external signalling and media address configuration

Hi, I am using Asterisk 15.4 version with PJSIP. My asterisk is on AWS ec2 instance with a public IP to it. It is also behind a firewall, So all my traffic has to go through the firewall, Firewall has public IP of its own.

What should I set for external_media_address and external_signaling address? Should it be Firewall IP or Asterisk IP? If there is any documentation on this can anyone please share, I couldn’t find any explanation about these variables on pjsip.conf sample file

external_media_address=
external_signaling_address=

Thanks

It is the external address that an outside party would use to reach the server.