TURN is a last resort, used only if all other methods failed.
TURN is a relay approach to connect client and server together, where
openttd.org (by default) is the middleman.
It is very unlikely either the client or server cannot connect to
the STUN server, as they are both already connected to the Game
Coordinator. But in the odd case it does fail, estabilishing the
connection fails without any further possibility to recover.
Before 8a2da49 the NewGRF names were synchronized using UDP packets, however
those have been removed. With this a new version of the GameInfo packet is
introduced that allows to specify the type of serialisation happens for
NewGRFs. Either only the GRF ID and checksum, or those two plus the name of
the NewGRF.
On this request for local servers will send the NewGRFs names.
The Game Coordinator will get the names on the first registration, and after
that only the GRF ID and checksum.
This method doesn't require port-forwarding to be used, and works for
most common NAT routers in home setups. But, for sure it doesn't work
for all setups, and not everyone will be able to use this.
This removes the need to know a server IP to join it. Invite codes
are small (~7 characters) indentifiers for servers, which can be
exchanged with other players to join the servers.
OTTD_COORDINATOR_CS for the game coordinator defaults to coordinator.openttd.org:3976
OTTD_CONTENT_SERVER_CS for the content server defaults to content.openttd.org:3978
OTTD_CONTENT_MIRROR_CS for the content mirror server defaults to binaries.openttd.org:80
The original idea was that people could find a server they could
talk in their native language on. This isn't really used in that
way. There are several reasons for removing this:
- the client also sends his "language" to the server, but nothing
is doing anything with this.
- flags are a bad way to represent languages, and over the years
we had several (rightfully) complaints about this.
- most servers have their language set to "All", and prefix the
servername with the language it is about. This is a much more
efficient way to do the same.
All in all, this feature should go back to the drawing board.
Maybe it could work in another form, but this form is not it.
-Codechange: Remove LAST_GRF_SLOT and MAX_NEWGRFS. Now NETWORK_MAX_GRF_COUNT is the only constant to specify the maximum number of non-static NewGRF.
-Codechange: Increase the number of file slots, effectively increasing the maximum number of static NewGRF and baseset GRFs.
Each server and game yield a (usually) different 'salt'. This salt is used by the clients to hash their passwords. This way the passwords are not sent in clear text and it is not trivial to use those hashes on other servers.
NOTE: It is still NOT safe to use your trusted passwords and it will not stop people from being able to 'hijack' your password, it only makes it harder to do and certainly much less trivial than just dumping passwords from the memory.
For example, launch on 192.168.0.1 with, say, netcat a listener: netcat -l -p 3982
Launch OpenTTD on a remote host (say, PSP): ./openttd -l 192.168.0.1 -d9
And you get all debug information on 192.168.0.1. Very useful for debugging Portable systems.