
Visualizing TCP (2010) - pmoriarty
http://research.swtch.com/tcpviz
======
userbinator
The diagram itself
([http://research.swtch.com/tcpviz.png](http://research.swtch.com/tcpviz.png)
) looks like an optical illusion - does anyone else feel like the horizontal
stripes are actually sloping downwards?

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Intermernet
Yes I did. The closest commonly listed illusion I can find is the Zöllner
illusion[1], but that uses uniformly lengthed, angled short lines in differing
directions to make parallel lines look unparallel. This uses a biased saw-
tooth to create the impression that the trend of the line gradually curves
down. I wonder if it has a name.

Interesting effect. It could be used nicely in many graphic design contexts,
although probably more subtly than demonstrated here.

[1]:
[http://en.wikipedia.org/wiki/Z%C3%B6llner_illusion](http://en.wikipedia.org/wiki/Z%C3%B6llner_illusion)

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fizwhiz
Awesome visualization! This is embarrassing to admit but I didn't know that on
establishing a connection there's 2 distinct stages: "ramp-up" and "full
bandwidth". Is this characteristic of every connection post-handshake? Could
someone be kind enough to explain what is happening exactly in the video after
the handshake?

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fjarlq
That's the slow start algorithm, part of standard TCP congestion avoidance:

[http://packetlife.net/blog/2011/jul/5/tcp-slow-
start/](http://packetlife.net/blog/2011/jul/5/tcp-slow-start/)

~~~
fizwhiz
Thank you, this was really helpful reading material!

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jschulenklopper
Somewhat similarly, visualizing web server traffic (from the access logs) can
be done with Logstalgia:
[https://code.google.com/p/logstalgia/](https://code.google.com/p/logstalgia/).
Enlightening to see your web server play Pong against an army of clients
firing requests at the server...

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usbreply
Your link ([http://vimeo.com/14439742](http://vimeo.com/14439742)) returns a
404 not found error.

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hariharan_uno
The link works fine for me. Try loading it again. Oh BTW the OP is not the
author of the article.

