What is lag switching?

@h2b2 said in #19:

I think I understand. turning the VPN off so lichess detects a disconnection and compensates you with time. the server is initiating the pings and detects a disconnection when it gets no reply.

Lichess doesn't detect a "disconnection" ... there is no disconnection... there is just a longer time before it gets a response to its pings. A disconnection doesn't occur unless there is a time out. (I.e. unless it takes too much time to get a response... which, as you surmised, will take about 30 seconds. )

Surely the client also initiates pings to detect if the server is alive?

There is no need. The connection is already established. The server pings the client to determine lag, not to see if the connection is alive.

If one of those pings hits lichess while the VPN is off, then it could be detected. To the server, it wouldn't be valid traffic, it would be a random tcp segment that doesn't belong to any connection the server knows about.

This doesn't make much sense to me... Even though the client doesn't need to ping the server, you are asking this with the assumption that it does, so let's go with that... I assume you mean that the client would end up pinging the server with it's provider-assigned IP (because the VPN is currently disconnected.) In that case, the server would respond to the ping as always... it wouldn't be an invalid tcp segment. This is getting a little muddied because standard ping uses ICMP, not TCP or UDP. (Although you can send a request over any protocol, await a response and call that "pinging".)

if someone plays a 30 move ultra bullet game and their connection drops out 30 times, that's a little suspicious. If that happens a second time, suspicion rises, after x times, ban.

Again, the connection doesn't really "drop out"... it just takes a longer for a response over that connection. I mean... "drop out" isn't really a technical term. Yes, you can say you drop the connection to your VPN, but the connection is still established until it actually times out. And lichess has no way of knowing why the response took a little longer. Might be perfectly normal network lag from a poor cellular or wifi connection or some issue with a node on the route or whatever.

I don't know what your technical background is, but it seems like you have some interest in networking. If you really want to dig into the details, I highly recommend you read some RFCs to really understand this stuff. RFC 1122 and 1123 are probably good starting points.

Ok. I didn't know about lag switching. that explains why I sometimes lose games against 2100 ultra players who get down to .8 seconds and then never lose time despite me checking them over and over again with premoves.

@wateenellende Good video.

Ah so it's an extension! So can't they scan for lag extensions similar to KB extensions and bans them the same way then?

Playing chess games with increment time is much better than playing with lag switches.

@RickRenegade said in #24:

@wateenellende Good video.

Ah so it's an extension! So can't they scan for lag extensions similar to KB extensions and bans them the same way then?

I encourage you to read more posts in this thread.

Lag switching is not an extension. It's a technique. It can be implemented in an extension, but there are other ways to do it that are somewhat less convenient and a lot less detectable.

Also, in a reply to a comment on that video, the guy who made the video and wrote the extension said, "Sorry, I don't plan on sharing this script with anyone. It's been sent to the Lichess admins who are already working on a way to ban this."

@Toscani said in #25:

Playing chess games with increment time is much better than playing with lag switches.

Agreed. But if someone is trying to cheat for an unfair advantage they don't want their opponent to have increment as well.

We need a Lagchess vaccine in our profile. A symbol that fights against lag switchers. Awarded to players playing against Berserker's of increment time.

The clock must remain the insurance, that the game will end.
The clock must not be excessive or overwhelming to end most games prematurely.
Above a 10 minute game, for me increment time is not essential, but if it drops below that, then I tend to prefer increment time. It helps combat the excessive stress caused by the clock streak players.

We need in our profile the Clock Streaks. How often a player wins in a row by the clock. Give them a Clock icon for top 100 on lichess. If we hover the mouse over the user name we would see the clock icon.
Games won in a row by the clock
Longest clock streak: 56 games
That would be a player to avoid.

@mrjbones Sorry I am noob with these things. Oh ok you can do it both. Oh well at least it should be easy to stop it when they do it through extension. Is there any other way to detect it? I think this might become a big thing and ruin online Bullet chess.

Lag switching is what sick f*d up morons do to waste their meaningless little lives ...

Just sayin bro ...