Here's an interesting post from SMS developer Mike Laksey. It's regarding the XBox chat system testing they are doing. However, it gives us further insight into how online works and why network problems can happen.
All ensuring our own internet connection gets a NAT 2 result is really important. Then everyone gets to see each other and talk in game. If you don't get a NAT connection when running the network test option from the PS4 menu then rebooting your router can sometimes fix that. If not contact your internet service provider.
Anyway here's Mike's post.
"Internal testing went well. External testing however we encountered some problems related to network connectivity, explained below.
To illustrate, using a 3 peer network, we have host (A), client 1 (B) and client 2 (C).
What happens in our peer to peer network is, B joins A's game and communicates successfully. Then C joins A's game and finds due to real world network conditions (NAT etc), he can communicate directly with B but not A. Our game detects this and allows C to stay in the game, with B elected as a relay for standard game traffic between A and C. In this situation, A, B and C can play together (caveat: if B leaves, C would become disconnected, unless another suitable peer has joined meanwhile).
So as far as that goes, everything is working normally, and hopefully makes sense.
Then there is chat game traffic. For our chat data, we don't relay it, at all, mostly because of bandwidth reasons (eg if multiple peers need to relay via client B, client B would sink). It is purely peer to peer. If there's no direct connection due to NAT, routers, etc, then the game chat between those peers will not work.
So where we are right now for patch 6 is that it will contain all the fixes to date. Potentially it may address certain people's game chat troubles, but it will not resolve them all.
Extending the relaying logic to include game chat management for pCARS 1 is too risky, so this part won't change. For pCARS 2, we intend to look at that again, to see if we can relay a certain quantity of game chat without impacting gameplay."
)
.
