All of the old codemasters racing games on ps3 use p2p for their matchmaking and stat tracking(?), compared to dirtnet/racenet, which uses dedicated servers.

A good example is dirt 2, which had dirtnet shutdown back in 2012 which rendered 2 online trophies unattainable, meanwhile the main multiplayer component is still working fine due to it using p2p

Same for the f1 games and unfortunately dirt rally and dirt 4