mbits or mbytes?

this question is not about FreeBSD, is a network question..

I'have a proxy, with tools like Iftop for watch the real time network activity
for years , use Mbits for see the proxy activity (download speed,clients/etc)
but if i'am wrong the real speed is Mbytes per second?

I do not know if my question is understood, i should use Mbytes or Mbits per second?

for example, when i download someting from a web browser,the speed is show in MBytes
 
mmm so, is a personal choise , for example systat -ifstat shows in bytes

i say this because i want to test the download speed from my work ISP
with this tool speedtest.py

the results in bits:

Code:
Testing download speed................................................................................

Download: 26.70 Mbit/s

Testing upload speed................................................................................................

Upload: 9.36 Mbit/s

and the results in bytes
Code:
Testing download speed................................................................................
Download: 3.19 Mbyte/s
Testing upload speed................................................................................................
Upload: 1.26 Mbyte/s

i feel like in the matrix o_O
 
Which is why I use this instead:
systat -ifstat -scale mbit

And then some coders decide to divide by 1000, some 1024 :eek:

And some divide by 8 to get MBytes/sec (how much user data is sent), while others divide by 10 to get MBytes/sec (how many physical bits are sent on the wire) due to every 8 bits of data requiring 10 bits be sent on the wire (8b/10b coding for Ethernet). :)

Both of these are technically correct, depending on what you are measuring: 10 Mbit/sec == 1.25 Mbyte/sec or 1 Mbyte/sec.

Isn't networking fun? :)
 
And some divide by 8 to get MBytes/sec (how much user data is sent), while others divide by 10 to get MBytes/sec (how many physical bits are sent on the wire) due to every 8 bits of data requiring 10 bits be sent on the wire (8b/10b coding for Ethernet). :)

Both of these are technically correct, depending on what you are measuring: 10 Mbit/sec == 1.25 Mbyte/sec or 1 Mbyte/sec.

Isn't networking fun? :)

indeed ,the fun never ends :D
 
8b/10b coding for Ethernet
This is still the case for the traditional serial communications too, 1 start bit, 8 bits data, 1 stop bit. I've generally just taken a factor of 10 for pretty much everything when converting between bits and bytes. It's easier to calculate in your head and you usually need to account for some protocol overhead anyway.

And then some coders decide to divide by 1000, some 1024
Not so much driven by the coders but more by standards. The SI standards define kilo, mega, giga, etc, as factors of 1000. Telecoms have always used factors of 1000. So 1Gbps is really 1000000000 bits per second, not 1073741824 bits per second. Harddisk manufacturers are also bound by the SI standards, so again a 1 GB harddisk is 1000000000 bytes, not 1073741824.

https://en.wikipedia.org/wiki/Binary_prefix#Deviation_between_powers_of_1024_and_powers_of_1000
 
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