[tor-relays] Proper bandwidth units [was: Exit nodes on Gandi]

grarpamp grarpamp at gmail.com
Tue Nov 19 00:28:36 UTC 2013

> Yes, and the global internet uses IP packets whose length
> is measured in bytes, not bits.

On paper in an RFC, yes, displayed on the actual routing
hardware as what you're pushing, no.

> No, that's still bogus. The only reason the hardware guys talked about
> bits/s was that that was the physical line limit, and that there was
> no consensus about protocols, or how many bits shall constitute a byte,
> or how many extra bits shall accompagny(sp?) the actual data.
> Nowadays bytes always have eight bits, it's always IP, and the transport
> is (almost) always fully efficient so that a byte/s always translates into
> eight bits/s.

This isn't a question of line/protocol encoding. Network hardware
ships databits around agnostic of that.

> There is simply no more reason to talk in bits/s at all,
> except that everyone is doing it.

Obviously, because backbone people buy and sell to
lower ISP's/hosters in bits/sec and your home line does too.
That's from the birth of the net and trickles down, the actual
choice and original rationale is moot, bits is what the upstream
measures things in today.
When you go to quote and plug in a large and 24x7 constant
bandwidth service like Tor, I2P, torrent, VPN aggregator, etc
the common language is often, and more easily to them, bits/sec.

> break down the
> TB/month my VPS provider gives me into bits/s or bytes/s. Neither is
> as straightforward as a decimal shift.

That's why real networks use bits/sec: it is
precisely an SI prefix shift, with no 8 divisor/multiplier
or 2^n involved anywhere. There's no ambiguity
and no math, just simple clarity.

VPS are by definition small, oversubscribed platforms, not
generally suited to large dedicated services. VPS providers
generally cater to the smaller apache style bytelog counting type
customer. Not the larger full on network (vpn, tor, router) customer.

And when we have people saying stuff like 'giga bits per
month', it's clear that confusion is perpuating in the field quite
well to the point you have no idea if they even know what
their own datapoint is. Then you have to ask them to
clarify their meaning, check their math, etc.

We've got 100Mbit or more nodes out there and dinky 512kbit
ones or less. For easy network reference, yes, people should
use bits/sec across the board here. If they insist on using Byte/sec,
at least use it right with SI 10^n prefix, not IEC 2^n prefix. And
don't come up with some unusual combination of prefix/time
as in the OP either.

For example...

A proper IEC gibibyte = GiB = 2^30 = 1024^3 = 1073741824
 for data storage, ram (binary bit handling)
A proper SI gigabyte = GB = 1E9 = 1000^3 = 1000000000
 for data transmission (packet counting, rocketships)


Thugh they may break your broken tradition, there are
current standards now, please use them.

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