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TCP in 30 instructions (1993)

www.pdl.cmu.edu Essays & writing Forum discussions Web & internet Candidate
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Resurfaced independently across 3 calendar years, with breakout response in 2 of them.

submissions
3
submitters
3
observed span
2010–2015
peak thread · 38 comments
132 pts
latest 20+ return · 2015-09-22
108 pts

Submission timeline

2007–2026

One slot for every year since HN launched. Height is that year's peak points; orange marks a 100+ point or 50+ comment breakout. Select a bar to open its strongest thread.

First comments on top threads

HN comment order

This is a very famous post, and Van Jacobsen is the archetypical networking systems programming bad-ass. Important context here though: this is just the per-segment receive processing piece of TCP; it's describing a very simple fast path that segments can take, but not all the TCP logic!

tptacek·132-point thread·

Previous: https://news.ycombinator.com/item?id=6971935 I was looking for a good link, this is a bit nicer to read but in pdf: http://people.cs.clemson.edu/~westall/853/notes/vanjtcp.pdf Stumbled upon when reading the linux receive path: https://github.com/torvalds/linux/blob/dd5cdb48edfd344017990...

majke·108-point thread·

Ah, yes, lightweight TCP processing... I remember working (as the MIT-EECS department systems guy) in the late 70's with the huge, galumphing, tortured BBN TCP/IP code for TOPS-20/TENEX, the first generation of TCP implementations, after the "big switch" that turned off all NCP (pre-TCP ARPAnet protocol) implementations in favor of TCP. Then I joined a startup in 80/81 building the first typesetting-quality laser printers, Imagen (a spin-off from Knuth's TeX project). We built controllers on the Andy…

cpr·58-point thread·

The first top-level comment from each of the four biggest threads, in HN’s own order. Excerpts are shortened; open a comment for full context.

Breakout years
2

100+ points or 50+ comments

Total points
298

reference only — not used in Hall rules or ranking

Total comments
49

reference only — not used in Hall rules or ranking

Every submission

DateTitle as submittedByPointsComments
2010-08-1730 instruction TCP receivextacy584
2013-12-27TCP in 30 instructions (1993)First breakout · Best threadadamnemecek13238
2015-09-22TCP in 30 instructions (1993)Latest 20+ point returnmajke1087