What is Relationship Between Internet Speed and Download Speed ?

Jovial_John


Joined: 31/01/2009
Posts: 1024

Message Posted:
29/10/2011 23:06

Internet speed is measured in megabits per second (so my Multimax link is 4 mb/s). The Utorrent speed graph shows the download rate in kbytes per second. I know that in principle there are 8 bits per byte but Utorrent isn't counting all the protocol overheads which must add a few bits per byte.

So what should I expect from Utorrent on a 4 mb/s link - I ask because Utorrent was peaking today at 710 kb/s which seems a lot higher than 4 mb/s?

I am sure Kemal or Erolz will provide a clear answer.

erolz


Joined: 17/11/2008
Posts: 3456

Message Posted:
29/10/2011 23:32

Not a simple subject in reality. However in simple terms multiplying the utorrent download rate, which I suspect but do not know, includes the inherent overheads with a bit torrent system, by 8 will give you an equaivalent bits per second speed.



So you 710kbytes per second = 710*8 = 5680 kbits per second = approx 5.5Mb/s



Really it is speed (throughput) over time that matters. A connection that delivers 6mbs for one second and 2mbs for the next in continuous cycle, to me would equate to a 4mbs connection. It's the average that matters in reality not the peak.



There is vast amount of devil in the detail, from software protocal overheads (p2p, hhtp, ftp), to network protocal overheads to how many bits or bytes there are in a kilo, mega and gigabyte - either 1000 or 1024 but in simple terms multiplying or dividing by 8 to get from bits per second to bytes per second and visa versa is a reasonable rule of thumb in my opinion.

kbasat



Joined: 28/07/2011
Posts: 481

Message Posted:
29/10/2011 23:53

The overheads are really not too much of a concern for a regular end user (the overall difference being no more than +/- 10% depending on how you calculate things) as we are not really trying to get a very precise result.



The reason why you are getting more than 4Mbits (normally you should see no more than 500kBytes/s on utorrent) is because of:



1) Since mid-October, we have started to configure all 4Mbits connections as 5Mbits, the reason why we are not publicly advertising and selling the package as 5Mbits is as follows, consider this as a 25% bonus on your speed and the proof of our promise that as we get more customers things will improve for the better and not for worse



(cont)

kbasat



Joined: 28/07/2011
Posts: 481

Message Posted:
29/10/2011 23:57

2) We also have smart bandwidth control features implemented which takes a lot of things into consideration and dynamically adjusts a client bandwidth for the better. Without going into too much detail, because we pay a fixed fee to telekom for a fixed amount of bandwidth, there is no reason not to allow our customers to take on more bandwith if it is available.



On a 4Mbit connection, you may see speeds up to 10Mbits(1.25mBytes/s on uTorrent) if 'all' the conditions are set right.



Hope this answers your question.



Kemal

Jovial_John


Joined: 31/01/2009
Posts: 1024

Message Posted:
30/10/2011 06:47

Thanks guys!



Erolz - I take your point about throughput over time but as far as I could see it never dropped below 600 kb/s (which does include bit torrent overheads) for the several hours I was downloading. So I am getting consistently more than I paid for.



Thank you Multimax.

Mr Vince


Joined: 24/07/2008
Posts: 696

Message Posted:
30/10/2011 13:55

I am probably more confused now.



Last night I had 7.6 MPS from Multimax but the TV programme I was streaming kept being interrupted and the message on the screen said that I had insufficient bandwidth. What's that all about

erolz


Joined: 17/11/2008
Posts: 3456

Message Posted:
30/10/2011 14:10

Mr Vince, the speed you actually get is dependent on the specific desitnation. So you can get a good speed to one destiantion and yet a bad one to another destination.



What was the source of the streaming TV programme ? Was it BBC iPlayer ? If so BBC iPlayer has it's own speedtest service here http://www.bbc.co.uk/iplayer/diagnostics which test the speed of your connection specifically to the destinations that the BBC sends streaming video from.



Also were you doing anything else with the connection whilst streaming video, like downloading or running a torrent program at the same time ? I am sorry if this is a stupid question to ask but not everyone realises that doing this kind of thing, whilst trying to also watch video stream, can have a major inpact on the streaming video.

kbasat



Joined: 28/07/2011
Posts: 481

Message Posted:
30/10/2011 22:05

This can actually be a very complicated matter indeed.



When you are downloading using torrent, it opens many connections, and downloads from multiple sources all at the same time, and as a result, the overall download speed can accumulate to a very big sum (but it may as well be multiple small downloads from all different locations, instead of one big download from one source)



When it comes to watching BBC or downloading a file or like from only one source (in this case BBC server), you rely on your connection establishing ONE streaming link to BBC servers and downloading. For this to work properly, you need sufficient bandwidth on your side to all the way to the BBC servers in the UK (going through multiple servers on the Internet to reach the destination). If the BBC servers or any one of the servers in between are not working optimally or overloaded, you may experience problems on this specific service while your internet works fine otherwise. (cont)

kbasat



Joined: 28/07/2011
Posts: 481

Message Posted:
30/10/2011 22:09

We have provided a simple speedtest tool at http://www.mmcyp.com . For multimax customers, this website is located at out Network Operations Center (NOC), just BEFORE our Internet exit. If you do not get satisfactory results on this website, it means that there is something wrong in your connection or some part of OUR network (and you should call us). If you get good results on this site but having other issues, the problem is usually NOT associated with our side of the network (exact cause needs to be investigated). This is not 100% the case, but mostly true.



Kemal