What's the difference between MB/s and mbit/s?

The data transmission rate units generally use MB/s or mbit/s, especially in the internal data transfer rate on the official data more use MBIT/S as the unit. There is a need to explain the difference between the two units:

The meaning of MB/s is megabytes per second, the meaning of mbit/s is megabits per second, which refers to the number of bytes transmitted per second, which is the number of bits transmitted per second. The B-letter in MB/s is the meaning of byte, although it is both bit and data unit of measurement, just like bit translation in mbit/s, but the two are completely different. Byte is the number of bytes, bit is the number of digits, in the computer every eight bits per byte, that is, 1byte=8bit, is 1:8 of the corresponding relationship. So 1mb/s equals 8mbit/s. So in the writing unit must pay attention to the case of B-letter, especially some people also mbit/s abbreviated to MB/s, at this time the size of B-letters can be called near misses, striking difference.

Above this is the general situation of MB/s and mbit/s, but on the hard disk data transmission rate can not use the general MB and Mbit conversion relationship (1b=8bit) to convert. For example, the official internal data transmission rate of a product is 683mbit/s, at this time can not simply think that 683 divided by 8 to get 85.375, it is considered that 85mb/s is the internal data transmission rate of the hard disk. Because in the 683Mbit also contains a lot of bit (bit) of auxiliary information, not exactly the hard disk transmission data, simple with 8来 conversion, will not be able to get real internal data transfer rate values.

1. Calculate the true speed of optical transmission

The use of fiber-optic connection network has a fast transmission speed. Less attenuation and other characteristics. So many companies are using fiber optics for their network exports. The average network service provider claims that the speed of the fiber is "5M", so what is the real speed of his download? Let's calculate, in general, "5M" is actually 5000kbit/s (by the decimal) there is a problem of conversion. The byte and bit are different. 1byte=8bit. And we often say that the download speed refers to the byte/s so Telecom said "5M" after conversion has become (5000/8) kbyte/s=625kbyte/s so we usually download the highest speed is 625kbyte/ S often denotes 625kb/s

In the actual case. The highest theoretical value is 625kb/s. Then also to eliminate the network loss and line attenuation and so on, so the real download speed may not be 600kb/s but as long as the 550kb/s is normal

2. Calculating the true speed of ADSL ADSL is the way we often use the Internet. Then telecom and Netcom claimed "512K" ADSL download speed is how much?

The conversion method is 512kbit/s= (512/8) kbyte/s=64kbyte/s, considering the loss of the actual download speed of the line in the 50kb/s above even if normal, then "1MB" that? Everybody count. The answer is 125kbyte/s.

3. Calculate the transmission speed of intranet

Often someone complained about how slow the transmission of the intranet in the real case, the speed of the 10/100MBPS network card should have more than that? The 100Mbps of the NIC is also defined by bit/s, so 100mb/s=100000kbyte/s= (100000/8) kbyte/s= 12500KBYTE/S in theory 1 seconds can transmit 12.5MB speed according to the interference factor transmission per second as long as more than 10MB is normal, now there are 1000Mbps network card so speed is 100mb/s

Special tips:

(1) A description of the conversion of bit (bit)/second (seconds) and byte (bytes)/s (sec): The line unit is BPS, which indicates bit (bit)/second (seconds), note is lowercase b; The rate units that users display when downloading online are often byte (bytes)/s (sec ), note that the capital letter B. The relationship between byte and bit is 1byte=8bits, and the actual transmission rate is about 10kbps when the transmission rate of IP header, HTTP header and so on is increased by network transmission protocol, and the 1kbyte/s download speed is displayed. For example: The download display is 50kbyte/s, the actual has reached the speed of 500Kbps. Remember to pay attention to unit!!!

(2) The broadband service rate that the user applies refers to the maximum theoretical rate value that can be reached by the technology, the user is also affected by the user's computer hardware and software configuration, the location of the website, the bandwidth of the website, etc.

(3) Theoretically: 2M (ie 2mb/s) broadband theoretical rate is: 256kb/s (ie 2048kb/s), the actual rate is approximately 103--200kb/s; (the reason is the user's computer performance, network equipment quality, Resource usage, network Peak, Web service capacity, line loss, The effect of multiple factors such as signal attenuation). The broadband theoretical rate of 4M (i.e. 4mb/s) is: 512kb/s, the actual rate is approximately---440kb/s.

Calculation method of broadband network speed

Basic knowledge:

In computer science, bit is the smallest unit of information, called bits, which is usually expressed in 0 and 1. Byte is called Byte and consists of 8 bits (8bit) of a byte (1Byte) that represents a character in the computer. Bit and byte can be converted between, the conversion relationship is: 1byte=8bit (or abbreviated as: 1b=8b), in the practical application of the general abbreviation, that is, 1bit abbreviated to 1b (note is the lowercase letter b), 1Byte abbreviation for 1B (note that the capital letter B).

In computer networks or network operators, in general, the unit of broadband rate is expressed in bps (or b/s), and bps represents bits per second, which represents the number of bits per second, and is the abbreviation for bit second. In practice, the 1M bandwidth means 1Mbps (Mbps is megabits per second without megabytes per second Mbps).

It is recommended that users remember the following conversion formulas:

1b=8b 1b/s=8b/s (or 1bps=8bps)

1kb=1024b 1kb/s=1024b/s

1MB=1024KB 1mb/s=1024kb/s

Spec hint: In the actual writing specification B should represent Byte (byte), B should represent bit (bit), but in peacetime actual writing some of the bit and byte mixed to B, such as both MB/s and MB/s are mixed to MB/s, resulting in the actual calculation of the confusion of the unit error. Remember to pay attention to!!!

Example: In our actual Web application, downloading software often see the words such as the download speed shown as 128KBps (kb/s), 103kb/s, and so on broadband rate size, because the ISP provides the line bandwidth used by the unit is bit, while the general download software shows the byte (1 bytes =8 bit), So you can get the actual value by conversion. However, we can use the conversion formula to convert the following:

128kb/s=128x8 (kb/s) =1024kb/s=1mb/s is 128kb/s=1mb/s.