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by superpatosainz 4344 days ago
IRC: everything is timestamped to the subsecond. Any drifting causes channel takeovers and "random" nick kills, even links fail. Also, since a message from a server is broadcasted across the entire network, one misconfigured server can cause chaos in your hubs or completely unrelated leafs.

Or at least that's how I remember my experience managing an unstable (as in ddosed, every irc service in active development, a few in-house bots, etc) IRC network and having read the IRC and IRCv3 specs and unreal's and TS6 server message specs. If I'm wrong I'm sure someone here could correct me.
1 comments
fanf2 4343 days ago
Your comment is very surprising. I don't see how clock drift can cause the problems you describe. There is no timestamping in the IRC protocol.

You can ask for a server's local time, but that is just for information.

There is a recently-added timestamp extension, but that seems to be to correct for delays so clients can record logs correctly. It is not for keeping the IRC network together.

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superpatosainz 4343 days ago
Yes, there is. Just not in the client side, it's server-to-server, and due to the centralised nature of IRC, it's critical.

For example, here's a paragraph from the UnrealIRCd server protocol (http://www.unrealircd.com/files/docs/technical/serverprotoco...):

> Unreal is very time-dependant. Users and channels, for example, are timestamped, and if server clocks are not synchronized properly, things can go very wrong very fast. See http://vulnscan.org/UnrealIrcd/faq/#67 for more information on this. Note that there is a slight difference between server time and what is actually reported by the UNIX date command or by the C time() function.

The other major side of IRC server protocol is the TS6 protocol (You can see it by yourself at http://irc-wiki.org/IRCd_Comparison). TS stands for TimeStamp, and you can see how critical timestamps are at https://github.com/avenj/irc-server-pluggable/blob/master/do... and https://github.com/atheme/charybdis/blob/master/doc/technica.... You can see TS are what control almost everything related to nicks, channels and their properties.

Before the implementation of TimeStamps and Services, it was really easy to abuse netsplits to take over channels and people's nicks.

There's a complete explanation at http://codeidol.com/internet/irc/The-IRC-Protocol/Timestamp-... (and of course, a Wikipedia link: http://en.wikipedia.org/wiki/Internet_Relay_Chat#Timestampin...).

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