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We can't send email more than 500 miles (2002)

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Re: We can't send email more than 500 miles (2002)

#31

Post by frandroid »

comex wrote: post #27
abeppu wrote: post #19

The ending of this makes it sound super clean. 3 ms * speed of light => ~560 miles. "It all makes sense!" But ... isn't the speed of light through fiber actually like 2/3 of the speed of light in a vacuum? And that fiber isn't going to be laid out in a straight line exactly to the destination. So I think really there must have been a fair bit of uncertainty around that ~3ms to abort a connection.

The FAQ addresses this: https://www.ibiblio.org/harris/500milemail-faq.html

Since the story has been posted umpteenth times, this is what should be posted these days. Very entertaining, thanks!

Re: We can't send email more than 500 miles (2002)

#32

Post by frandroid »

akeruu wrote: post #12
anamexis wrote: post #4

Earlier quoted context omitted.

A few more: https://news.ycombinator.com/item?id=12778904 https://news.ycombinator.com/item?id=21578606 https://news.ycombinator.com/item?id=16384158 https://news.ycombinator.com/item?id=16285093 https://news.ycombinator.com/item?id=12997568 https://news.ycombinator.com/item?id=3802458 https://news.ycombinator.com/item?id=123489 https://news.ycombinator.com/item?id=385068 https://news.ycombinator.com/item?id=2701063…

Yes, this story gets posted a lot, and many of us might know it, but at the same time, I like to think about the ones that didn't. They will learn something new today. XKCD said it better than I could: https://xkcd.com/1053/

One of the most endearing xkcd strips. A bit lightbulb moment when I figured this out in my life.

Re: We can't send email more than 500 miles (2002)

#33

Post by umvi »

comex wrote: post #27
abeppu wrote: post #19

The ending of this makes it sound super clean. 3 ms * speed of light => ~560 miles. "It all makes sense!" But ... isn't the speed of light through fiber actually like 2/3 of the speed of light in a vacuum? And that fiber isn't going to be laid out in a straight line exactly to the destination. So I think really there must have been a fair bit of uncertainty around that ~3ms to abort a connection.

The FAQ addresses this: https://www.ibiblio.org/harris/500milemail-faq.html

The FAQ was more entertaining than the actual story!

Re: We can't send email more than 500 miles (2002)

#35

Post by mensetmanusman »

xwdv wrote: post #7

IMO even though this has been posted a bunch of times it’s important to repost these sort of campfire ghost stories so future developers can think more creatively about strange errors.

Is there a book written about these campfire programming stories?

This one and the microsoft bedlam one are some of my favorites.

Re: We can't send email more than 500 miles (2002)

#37

Post by bobblywobbles »

Can someone please explain to me the POP reference? I do not understand what this author means by that.

I also would like help understanding what $ units gives? The command looks to be "units", but where do the numbers he entered in come from? I would appreciate this extra context.

Re: We can't send email more than 500 miles (2002)

#38

Post by sonofgod »

bobblywobbles wrote: post #37

Can someone please explain to me the POP reference? I do not understand what this author means by that. I also would like help understanding what $ units gives? The command looks to be "units", but where do the numbers he entered in come from? I would appreciate this extra context.

$ is the shell prompt; he's not typing it. "3 millilightseconds" is the distance light travels in 3 milliseconds, the time a "zero" timeout would take to actually timeout. (This comes directly from the definition of the lightsecond: how far light travels in one second) "miles" is what he wants to see that distance converted to. Turns out it's 558 miles; one mile is 0.00179 of 3 millilightseconds.

Re: We can't send email more than 500 miles (2002)

#39

Post by dahfizz »

bobblywobbles wrote: post #37

Can someone please explain to me the POP reference? I do not understand what this author means by that. I also would like help understanding what $ units gives? The command looks to be "units", but where do the numbers he entered in come from? I would appreciate this extra context.

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