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SYN

When TCP sockets refuse to die

09/20/2019

SYNTCPSpectrumTech Talks

We noticed something weird - the TCP sockets which we thought should have been closed - were lingering around. We realized we don't really understand when TCP sockets are supposed to time out! We naively thought enabling TCP keepalives would be enough... but it isn't!...

SYN packet handling in the wild

01/15/2018

SYNTCPProgramming

Here at Cloudflare, we have a lot of experience of operating servers on the wild Internet. But we are always improving our mastery of this black art. On this very blog we have touched on multiple dark corners of the Internet protocols: like understanding FIN-WAIT-2 or receive buffer tuning....