# QuestionUnderstanding Megabits / Megabytes

#### Witterings

##### Reputable
I get that with ADSL it's Megabits per second and is normally typed Mbps and there are 8 Bits to a Byte normally typed as MB/s but if I'm looking at older routers / switches that are 10/100 with the newer ones being quoted as 1000 are they talking about Bits or Bytes???

Also if I copy and paste a file across a network on Windows and use the drop down box to see the transfer speed say at approx 50 to 70 again is that Bits or Bytes and is there any difference then between if it's Wired or Wireless

Also if I see a Wireless network card speeds quoted as 300/857, does that mean 300 upload vs 857 download or i sit the difference between 2.4 and 5GHz and they're talking megabits .... so in a perfect world with no data loss (appreciate that doesn't happen) if I'm transferring a file from a wireless laptop to a wired device on the network the maximum upload speed will 300 divided by 8 = 37.5 megabytes .... is that correct.

I appreciate these are probably pretty rudimentary questions to someone who's been interested in IT for a while but it's relatively new to me and any help would be much appreciated.

##### Honorable
"1000" means 1000Mbits = 1Gbit

Windows explorer reports file transfer in bytes, specifically megabytes per second (MB\s). There is no difference in terms of speed reported by Windows, it doesn't care how you're connected. Wired connection will always be better.

Yes, WiFi and network cards always state their speeds in mega- or gigabits, and figures like 150/300 mean different speeds for different WiFi channels or local infrastructure speeds.

#### QwerkyPengwen

##### Dignified
In regards to internet and connectivity, megabits is more or less a measurement for speed, where as megabytes is a measurement of data and sizes on storage.

When you look at a router that says it supports 10/100 Ethernet, it is saying that it supports only the two older modes of Ethernet cables at a maximum of 100 megabits per second. A router that says it supports 1000 is gigabit over Ethernet which requires at least a cat5e cable I believe.

When Windows is telling you the speed at which a file is transferring, that is measured in file size and is megabytes.

As for WiFi stuff, more or less what trad just said. Higher numbers is better in general but especially for transfer speeds of files over WiFi.

#### Witterings

##### Reputable
Brilliant and cheers for the quick replies much appreciated!!

Just to clarify a bit further on the Wireless card, the one I have is 300/857 so does that mean the 300 refers to 2.4GHz and the 857 - 5GHz both up and downstream, if I'm connected to the 5g I'm only seeing data transfer speeds of a maximum approx 22MB\s if I'm going upstream from the wireless laptop??

#### bill001g

##### Titan
Wifi numbers are not actually transfer rates they are related to how the data is encoded. As you suspect they have added upstream and downstream together. They also ignore a rather substantial overhead in the data transmission. The overhead gets worse the more complex they make it like running 4x4 mimo.

In general if you get even 1/4 of the number that is a very good result.

#### QwerkyPengwen

##### Dignified
To my knowledge those two numbers are in reference to the maximum rate at which data can be transferred over that particular band/frequency

However, in regards to a router that doesn't support 5ghz, then those two numbers would be in reference to G and N connectivity types over 2.4GHz (you know, all those fancy letters at the end of 802.11a/b/g/n? yeah, those are generational improvements to WiFi over the years with the newest being ac/ax which are dual band meaning a device that can support ac supports connecting to both 2.4 and 5GHz at the same time to increase connectivity and speeds but only on a router that supports dual band connections as well)

#### alceryes

##### Distinguished
Just an extra tidbit here.

When you see a little 'b' (Mbps) it refers to megabits. If you see a big 'B' (MBps) it refers to megabytes. These are also seen as Mb/s or just Mb for megabits and MB/s or just MB for megabytes.

1 megabyte is equal to 8 megabits. Of course, these also translates upward to gigabytes/gigabits, terabytes/terabits, etc.

Making this distinction is important when dealing with any kind of throughput with internet, wireless, or data transfer. You'd be surprised how many don't know the distinction and give incorrect info.

In the past it has caused numerous issues (for me at least) when dealing with SAN/NAS tech support from overseas where they switch between the bits and bytes distinction almost per conversation. I would swear that they always try to be as vague as possible, on purpose.

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#### Witterings

##### Reputable
Thank you again to everyone for their help ... it's been really useful!!