Make sure you’ve read Understanding Throughput and TCP Windows before watching this video. I mean, you don’t HAVE to, but I recommend it.
No one’s ever asked you why the network is slow, right? Hahahahahaaaaaaa haa ha. Ha. Oh man. What a funny joke. The better question is can you think of a day in which someone DIDN’T ask you that question?
It’s frustrating because that one time 6 months ago when it was the network means that since then anytime someone’s cat video doesn’t instantly load they’re asking you about the network. And it seems like you have no way to tell them to get lost because how can you prove it’s not the network?
I’m here to tell you that you can prove it and I gave you one example of when it’s not the network in the last video. Now I’m gonna show you a couple more.
In this video, I walk you through two captures. One shows throughput bound by the receiver and the other by the sender. Again, if terms like “receive window” or “congestion window” or “send buffer” don’t make sense to you, go read the link above first.
I sometimes worry about how long these videos are, but the thing is I’m only covering maybe 75% of what I could talk about in the capture files. There’s just so much information and I don’t want it to be overwhelming. I’m trying to give you a depth that you can’t get much place else. If you really want to learn this stuff, you’ve got to be willing to make an investment of your time. Just watching a 5min video ain’t gonna do it. Feel free to leave a comment about this topic.
Grab the sendwin-bound.pcapng file and tell me in the comments why sometimes it sends only 64k before waiting for an ACK when most times it sends 128k.
Also, if you’d like to look it over, here’s the recvwin-bound.pcapng