I always get confused about this. Is开发者_如何学C there a "standard" conversion of Megabits to bytes?
Is it:
1 Megabit == 1,000,000 bits == 125,000 bytes
Or:
1 Megabit == 2^20 bits == 1,048,576 bits == 131,072 bytes
Megabits is a unit of measure that comes from TELECOM, not CS. So it is:
1 Megabit == 1,000,000 bits == 125,000 bytes
When it's a CS based unit of measure, usually the 1024
rules apply:
1 Megabyte = 1,024 Kilobytes = 1,024 x 1,024 bytes
One megaoctet (only the same as a megabyte if each byte has eight bits) is eight megabits. Exactly the same conversion applies as for megabytes.
A one "megabit" RAM, ROM, or flash memory chip has 10242 mebibits (Mibit) = 1 048 576 bits.
A one megabit per second Internet connection can transfer 10002 megabits (Mbit) = 1 000 000 bits per second.
So four different conversions of "megabits" to "megabytes" may apply (assuming that each byte does have eight bits):
- 1 Mibit (mebibit) = 8 MiB (mebibytes) = 8 388 608 B = 8.388608 MB (megabytes)
- 1 Mbit (megabit) = 8 MB (megabytes) = 8 000 000 B ≈ 7.6294 MiB (mebibytes)
It's the former.
http://en.wikipedia.org/wiki/Megabit
1 megabit = 0.125 megabyte
google it
Alright, I didn't mean for my answer to cause such uproar, but as all of your comments are valid, I figured I would come back to help clear up my reputation a bit.
I believe the correct answer to the whole question is that a
- Megabit is 1,000,000 Bits
- Mebibit is 1,048,576 Bits
- Megabyte is 8,000,000 Bits
- Mebibyte is 8,388,608 Bits
So the original question is not a matter of which one is correct, but that they have the wrong name to the label.
1 Megabit == 2^20 bits == 1,048,576 bits == 131,072 bytes
Should instead be:
1 Mebibit == 2^20 bits == 1,048,576 bits == 131,072 bytes
Kilo is 1.000, Mega is 1.000.000 times of whatever it is. Such as Kilogram is 1.000 gram. Kilohertz is 1.000 hertz so on.
Same for Mega, MegaHertz is 1.000.000 hertz, Megabit is 1.000.000 bit.
Since 1 byte is 8 bit, then 1.000.000 / 8 = 125.000 byte.
When it comes to computer, the multiplier changes slightly, such as Kilo is 1024 times and Mega is 1024*1024 = 1.048.576 times of whatever it is (in generally bit).
In this case 1 MegaBit = 1.024 * 1.024 = 1.048.576 bits, in terms of byte 1.048.576/8 = 131.072 bytes.
While there is a movement to introduce Mebi
and the like as the measurement for the power of two units, the usage isn't universial or accepted. However, from experience, bits are most likely to be depicted with the normal definition of Mega
, so 1,000,000 bits
.
It may vary by industry. Component manufacturers offering FLASH products advertise their products as "1Mbit" and contain "131,072 bytes". (Reference: SST's 1 Mbit SPI Bus Serial FLASH (PDF Datasheet); indexable addresses 0h-1FFFFh)
https://wiki.ubuntu.com/UnitsPolicy
UNIT POLICY. this is new unit policy for all 2 base and 10 base units
The binary meanings are more commonly used in relation to solid-state memory (such as RAM)
while the decimal meanings are more common for data transmission rates, disk storage and in theoretical calculations in modern academic textbooks."
for more innformation see
https://en.wikipedia.org/wiki/Wikipedia:Manual_of_Style/Dates_and_numbers#Quantities_of_bytes_and_bits
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