I'm using the Samsung messages app on the sprint network. It's configured for RCS, however, when I'm on my home wifi network I don't receive messages from other RCS users. I do not have any outbound firewalls configured. Are there inbound connections that are expected? Are there specific ports I should be looking at? I can set up a connection on TCP port 5061 no problem which is what some Internet users suggested might be the right thing but RCS still does not work. Note I can send messages, I just cannot receive them, nor see any of the 'online, delivered,read' indicators for messages. I have been unable to find anything that talks about how Samsung has implemented this, though I know google has moved its messaging app to port 443 to avoid the firewall issue. And yes my phone has taken all available updates.
Thanks for the response. My router generally blocks all incoming traffic and outbound (internally initiated traffic) is allowed. After testing various ports, I did stumble across the note about "filter useless". I'm using Samsung Messages and basically if I had the chat feature on it wouldn't work when I was on my wifi, if I forced it to SMS of course things worked fine (I think it actually runs over port 5061). Turns out in dnsmasq.conf on linux it actually outright says that if you turn this on it will block SIP. RCS uses SIP and MSRP. I certainly didn't remember when I set up my dnsmasq filters.
|# Uncomment this to filter useless windows-originated DNS requests|
|# which can trigger dial-on-demand links needlessly.|
|# Note that (amongst other things) this blocks all SRV requests,|
|# so don't use it if you use eg Kerberos, SIP, XMMP or Google-talk.|
|# This option only affects forwarding, SRV records originating for|
|# dnsmasq (via srv-host= lines) are not suppressed by it.|
So maybe this will help other folks, because 'filter useless' didn't mean much to me