Need a quick tech explanation

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Sintac

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Good day all. :)

I was just wondering what the technical term for this is?

I have a 4096Mbps line speed, here is a SpeedTest,
http://www.speedtest.net/result/634065648.png
So that is + - 437KB/s

What I am wondering is why dont we get the full 4096Mbps speed, what is holding us back?

In the above SpeedTest I am losing 0.596Mbps witch is a + - 75KB/s loss.

Just so you guys know I am not complaining, the speed is fast, just want to understand why this is.

Thank You.
 
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Local copper / exchange infrastructure capacity - you should be addressing your query to Telkom, however they will inform that they only guarantee speeds up to 1 MB/s.
 
who.is.michael said:
Local copper / exchange infrastructure capacity - you should be addressing your query to Telkom, however they will inform that they only guarantee speeds up to 1 MB/s.
Click to expand...

I have no problems with my connection, I am synced at 4096Mbps 24/7, just wondering if there is another explanation. I have read in another post about something like Tcp Overhead but not sure if that has to do with my question.
 
Sintac said:
Ok cool, that might be the technical term, can you maybe explain what that means? Please. :)
Click to expand...

To be a simple as possible the protocol which the Internet uses to transmit data between different computers is sent in packets which are basically tiny snippets of data which are assembled and reassembled by your router. Each of these packets contains information about origin and destination etc which in itself is a bit of data. Think of it as a letter with an address and return address on the envelope. The addresses are required to deliver the letter however this increases the number of characters or text needed for the contents of the envelope to be delivered. This is the overhead being referred to.

That's as simple as I can put it ;)
 
Sintac said:
Ok cool, that might be the technical term, can you maybe explain what that means? Please. :)
Click to expand...

Its kind of like beer .. think of your data like a draft glass .. and beer as the data you want .. when you fill the glass ... you always get a little head (or headers ;) ) .. that takes up space in the glass .. but isnt really part your "500ml beer expectation"

But in your case I dont think its that .. cause when I had a 4 meg line .. I got my full speed .. could be noise on the line and that is accounting for some packet loss .. the service is not a 4meg service .. its only guaranteed as a 1meg service with an up to 4 meg side clause .. so technically .. as long as you are somewhere between 1 and 4 meg .. thats acceptable .. although most people get close to 4meg (like you) and some get even closer.

hmmm... thinking of beer always makes me smile .... (eyes glaze over ...)
 
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Thanks for the simplified explanation, just for interest sake is there a way to fix this, I understand this is not realy a problem, but is there anyway around it?
 
Sintac said:
something like Tcp Overhead
Click to expand...
That will have a small impact, however your greatest loss comes from the overhead of ATM cell headers (~10%). ADSL is inherently based on ATM technology, therefore no way around it.

If you're getting ~ 3600 Kbps on the IP packet level or ~ 3500 Kbps on the IP payload level (dl speed), your line is running near 100% efficiency. So your 437KBps (3496 Kbps) is pretty much spot on.
 
PallBearer said:
yes, you could redefine the OSI model.
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rofl

unfortuanatly there is nothing else u can do to improve the situation any internet connection has this "problem" line quality and signal strength affects this speed more than overhead

but something to make u feel better imagine those guys 384 kb line getting bout 300-340 max
 
think of it as trying to send a letter via the post office.

you don't put it in an envelope and your dont address the letter or have a return address. Same as an TCP packet. it don't know where to go, where it came from...what position of the original file it came from...nada..niks...so it has to have those "overheads" in order to work.
 
The highest I've seen my line stable at is ~450kbps.

Also keep in mind that most modern downloads ( torrents , download managers , anything really ) set up multiple connections. Each one of those connections will have overhead as explained by the other guys.

So if your hitting your line doing multiple things and your total line speed is round 430, that aint bad.

For a bit of fun, run this command in your cmd prompt when downloading a lot -> netstat -a , if your on a windows system. This is a tool within windows that will show you all the connections that your machine is running at the moment.
 
jetlee said:
Its kind of like beer .. think of your data like a draft glass .. and beer as the data you want .. when you fill the glass ... you always get a little head (or headers ;) ) .. that takes up space in the glass .. but isnt really part your "500ml beer expectation"
...)
Click to expand...

Probably the best explanation I have heard to date, I love it :D


PallBearer said:
yes, you could redefine the OSI model.
Click to expand...

Lol, start churning out those RFC's :D


MWEB said:
That will have a small impact, however your greatest loss comes from the overhead of ATM cell headers (~10%). ADSL is inherently based on ATM technology, therefore no way around it.

If you're getting ~ 3600 Kbps on the IP packet level or ~ 3500 Kbps on the IP payload level (dl speed), your line is running near 100% efficiency. So your 437KBps (3496 Kbps) is pretty much spot on.
Click to expand...

+1 Forgot about the ATM overheads, has a big 5-byte cell header.
 
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