3 MB speed transfer on network; where have I gone wrong?!

slipd · 23 Mar 2013 at 09:59

Hi guys,

As above, last night I copied a backup file (.img) from one machine to another, it is roughly 65GB but after about 20 minutes of no visual progress I looked to see what the transfer speed was - it was 3 MB, tops :mad:

The remote machine has a Linksys N wireless card (270-300 MB) and that talks to my Billion 7800N router which plugs into my 200 MB homeplugs which in turn feed into the other machine which has a 1 GB onboard nic.

I can't see where the bottleneck could be?

Any ideas

KIA · 23 Mar 2013 at 10:03

Don't get bytes confused with bits. What speed is the wireless link running at?

andy_mk3 · 23 Mar 2013 at 10:04

What speed are the homeplugs physically connected at?

slipd · 23 Mar 2013 at 10:28

Thanks for the replies!

Right, the wireless nic is definitely showing a 'speed' of 270 MB as I type and the homplugs are running at 104 MB.

paradigm · 23 Mar 2013 at 10:47

sam.wheale said:
Thanks for the replies!

Right, the wireless nic is definitely showing a 'speed' of 270 MB as I type and the homplugs are running at 104 MB.

Well, the homeplugs at that speed give you a theoretical maximum of 13MB/s, but due to protocol overheads I wouldn't expect to see more than about 85-90% of that, so call it 11MB/s tops.

tribz · 23 Mar 2013 at 11:10

Assuming you actually get at least 10Mb/s out of it, that 65GB file will take 15hrs to transfer. At 3Mb, around 3 times that.

Despite your wireless link speed saying 270Mb, you'll only get a fraction of that with 3-7MB/s being real world speeds

As KIA mentioned, dont get your Mb's confused with your MB's

slipd · 23 Mar 2013 at 11:22

Thanks people! Bottom line then: its my homeplugs?

tribz · 23 Mar 2013 at 11:38

I'd say bottom line is its your wireless, its far too big a file to transfer over a wireless segment. Homeplugs wont be massively quicker either, your still looking at a very long time to transfer that file over the homeplug segment.

EnviableOne · 26 Mar 2013 at 09:39

Data transfer is Mesured in MBps (Bytes) and connections in Mbps.

conversion B = 8b

which puts wireless at 33.75 MB/s and Homeplug at 25MB/s, thats at full speed, knock off about 5-10% for fram headers and take into account that both Homeplug and Wirless have Contention, you are looking at lower rates above.

if your gonna use Homeplugs for data transfers of this size, definatley think about stepping up to the 500Mbps, and the wireless look at draft ac.

But save time and money and get the drill out and run some cable, you'l be getting data rates about 125MB/s approximatley 5 times faster than full speed on the wireless/Homeplug combo, and no contention.