Comment 10 for bug 240073

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Neal McBurnett (nealmcb) wrote : Re: Ifconfig uses incorrect units

I agree that a good citation on the units used for of datacom like ethernet would be useful. A bit of poking thru
 http://standards.ieee.org/getieee802/download/802.3-2005_section1.pdf

shows lots of references to things like "100 Mb/s" and "1000 Mb/s" but I haven't found a totally clear statement clarifying that they mean SI Mega = 10^6 when they say "M". This ongoing discussion of using "M" to mean 2^20 is the only thing that gives me pause.

But wikipedia, which cites the spec above, is quite clear that these are all real traditional SI powers of 10:

 http://en.wikipedia.org/wiki/Bit_rate

 When describing bitrates, binary prefixes have almost never been used and SI prefixes are almost always used with the standard, decimal meanings, not the old computer-oriented binary meanings. Binary usage may occasionally be seen when the unit is the byte/s, and is not typical for telecommunication links. Sometimes it is necessary to seek clarification of the units used in a particular context.

That all leads me to wonder why anyone would ever have divided by anything other than a power of 10 in ifconfig. I agree with Alan Cox (in the Redhat bug at https://bugzilla.redhat.com/show_bug.cgi?id=118006#c4 ) that we should just be using traditional SI units and dividing by 10^6, and update the man page at the same time.

ifstat labels bandwidth as KB/s, and iptraf labels it as kbits/s, but I haven't figured out an easy way to find out what they are really dividing by, and haven't checked the code.

At any rate, diverging from Debian just by calling "MiB" "MB" instead seems the worst of all worlds.