TechWhirl (TECHWR-L) is a resource for technical writing and technical communications professionals of all experience levels and in all industries to share their experiences and acquire information.
For two decades, technical communicators have turned to TechWhirl to ask and answer questions about the always-changing world of technical communications, such as tools, skills, career paths, methodologies, and emerging industries. The TechWhirl Archives and magazine, created for, by and about technical writers, offer a wealth of knowledge to everyone with an interest in any aspect of technical communications.
Oops. You're absolutely correct. I screwed up. My apologies.
In the joy of actually having a calculation to fool around with, I let my brain slip into idle and let my fingers do the thinking. No. Wait. It was the calculator's fault. Yeah. That's it. The calculator did it. :-{)
Al Miller
"Chief Documentation Curmudgeon"
Prometric, Inc., a part of The Thomson Corporation
Baltimore, Maryland
www.prometric.com
A lie gets halfway around the world before the truth has a chance to get its pants on.
-- Sir Winston Churchill
-----Original Message-----
From: Dick Margulis [mailto:margulis -at- mail -dot- fiam -dot- net]
Sent: Thu 4/24/2003 4:32 PM
To: TECHWR-L; Miller, Alan
Cc:
Subject: RE: On PDFs
Whoa there, Alan! You're a cuppa coffee short this afternoon. Kbps is kiloBITS per second, not kiloBYTES per second.
Let's start over. 1 KB = 1,024 bytes = 8,192 bits. MIME encoding blows that up by a factor of about 1.5 for reasons not entirely clear to me, so call it 12,000 bits. At 56 Kbps, that's a little over 0.2 s per KB or about 3 m per MB.
Or did I screw up, too?
Dick
"Miller, Alan" <Alan -dot- Miller -at- prometric -dot- com> wrote:
>
>rbilbao -at- us -dot- amadeus -dot- net asked:
>>>Does anyone know where I can get some cold hard facts about PDF download times?<<
>
>Easy question. <Rhetorical question>So how come nobody's answered it yet?</Rhetorical question> The answer is: "In your calculator." :-{) Use this simple formula:
>
>File size (bytes) / Transfer rate (bytes per second) = Time for transfer (seconds)
>
>If your file size is given in kb, multiply by 1024 to get bytes (a kb is *not* 1000 bytes; it's 2^10 bytes, or 1024). Likewise, multiply Mb by 1,048,576 to get bytes (a Mb is 2^20). Then, divide by the transfer rate (56,000 bytes per second; this time kbps *is* 1000 bytes per second).
>
>If you have a 1 kb (1024 bytes) file to download at 56 kbps, you get:
>
>1024 bytes / 56,000 bytes/s = 19 s (rounded to two significant digits, the lowest precision of my input numbers)
>
>Hmmm. Looks like a thumb-rule to me: 1 kb at 56 kbps = 19 s
>
>If you want minutes, divide by 60; for hours, divide by 3600.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Last chance to order RoboHelp X3 and receive a $100 mail-in rebate,
PLUS free RoboScreenCapture and WebHelp Merge Module. Offer expires
4/30/03! Order here: http://www.ehelp.com/techwr-l
Help celebrate TECHWR-L's 10th Anniversary starting this month!
Check out the contests at http://www.raycomm.com/techwhirl/special/contests/
Happy birthday to you, happy birthday to you, happy birthday TECHWR-L....
---
You are currently subscribed to techwr-l as:
archive -at- raycomm -dot- com
To unsubscribe send a blank email to leave-techwr-l-obscured -at- lists -dot- raycomm -dot- com
Send administrative questions to ejray -at- raycomm -dot- com -dot- Visit http://www.raycomm.com/techwhirl/ for more resources and info.
