How long does it take to backup 1,5 TB of data to iCloud Drive?

[creat0r]

How long would it take to backup 1,5 TB of data to iCloud Drive with an internet upload speed of 50 Mbit/s? I live in Sweden. No, I don’t want a NAS.

[Lurick]

At full 50Mbps nonstop? ~3 days

[Eigenvektor]

You can easily calculate that yourself.

 

1.5 TB -> 1,500 GB -> 1,500,000 MB

50 Mbit (÷ 8 bit/byte) -> 6.25 MB/s

 

1,500,000 MB / 6.25 MB/s -> 240,000s (÷3600 s/h) -> 66,67h (÷ 24h/d) -> 2.77 days

 

Alternatively, you can let Google do the math: https://www.google.com/search?q=1.5+TB+%2F+50+Mb%2Fs

(just make sure it is using Mb not MB)

[E-waste]

I have been inforned tbat in networking, you shouod divide by 10, for one start bit, and one stop bit.  This was from someone who works with networks as a living, so I'm sure this person is quite well aware of the topic.

 

It was mentioned because I said the same thing, divide by 8.

 

So, now you know!

 

My calculations far exceed 2.5 days, it is actually closer to

3.47 days, using 10 bit division.

 

You do not need a NAS.  Just buy a 2TB 5400 RPM hard disk for cheap on ebay, and keep your pictures and music and all that local, a nas is not a requirement.  You can hook up a hard disk with USB cables now, called external disks.

 

Taking 2.5 or 3.47 days to upload, with that data needing to be streamed or redownloaded seems like way too much annoyance, and what if your internet service somewhere is inaccessible?

 

There are adapters to hookup flash drives and I'd assume hard disks too directly to an iPhone, so you can have your hard disk with you anywhere you go.

[mariushm]

No, there's no start bits or stop bits. That may be the case for serial ports or other protocols, not with ethernet. 

 

Your ethernet port is 1 gbps, which means giga bits, so you divide by 8 and you get bytes... so it means a maximum transfer speed of 125 MB/s  - mega bytes or millions of bytes.

 

Due to using TCP/IP, the data is arranged in packets which have their own header (between 20 to 60 bytes per packet, where a packet is maximum 65535 bytes, but around 1500 bytes is most used...  see https://en.wikipedia.org/wiki/Internet_Protocol_version_4#Header), so you're looking at an overhead of maybe 1-2 MB when you're saturating the link with a transfer, so realistically you could transfer around 122-123 MB/s on a gigabit connection. 

 

100 mbps is 12.5 MB and realistically you would transfer around 12 MB/s of usable data. 50 mbps is half of that, so you're looking more like 6-6.1 MB/s

 

Note that it's MB as in million of bytes , 1 MB = 1,000,000 bytes. 

 

When you're looking at File properties in Windows explorer, it will tell you the file sizes in multiples of 1024, as in 1 MiB = 1024 KiB  = 1,048,576 bytes so if you look at File Properties at a file and it's 1000 MB, it doesn't mean it will take 100 seconds to upload it at 10 MB/s,  because that 1000 MB shown by Windows explorer is actually  1000 x 1024 x 1024 / 1000 / 1000 = 1048 MB, so it would take 1048 / 10 = 104.8 seconds - more than 104.8 seconds (a bit more than this in reality but it's already too complicated so let's just leave it here)

 

 

- going back to the original question ... 50mbps is around 50/8 = 6.25 MB/s but realistically let's say 6.1 MB or 6,100,000 bytes.  (because in 6,250,000 bytes you can fit around / 1500 = 4166 packets x ~32 bytes overhead = 133,312 bytes overhead)

 

If those 1.5 TB are as reported by file properties in Windows explorer, using multiples of 1024, then in ideal world where you would saturate the internet connection, you would complete the transfer in a minimum

 

1.5 x 1024 x 1024 x 1024 x 1024 / 6,100,000  = 1,649,267,441,664 / 6,100,000 = 270,371.7 seconds  = 4,506 minutes = 75 hours = 3.129 days.

 

 

[problemsolver]

On 8/12/2023 at 8:22 AM, creat0r said:

How long would it take to backup 1,5 TB of data to iCloud Drive with an internet upload speed of 50 Mbit/s? I live in Sweden. No, I don’t want a NAS.

Lots of good posts here, but if you just want a simple answer to your question:

 

Question answered on Wolfram Alpha

 

I've found Wolfram Alpha to be a much better at responses to these types of questions than Google, and the data it gives you in the responses can make it easier to see if you've made an mistake in how you typed in the question.

 

  Remember:  MB/s ≠ Mb/s so when you're typing into Wolfram Alpha make sure you use bytes (B) or bits (b) as appropriate.  (Generally file sizes are in bytes and internet speeds are in bits.)