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jerry_23
08-07-2003, 12:38 AM
I have two computers, one running Windows 98, the other running XP Home. When I transfered a 10 MB file, it took roughly 10-15 seconds...this sounds a bit slow. The speed of both network cards are 10.0 Mbps, and I am using cat 5e cables, so why does it take so long for a 10MB file to transfer? Is there a good network program that optimises speed? Also, is the 10.0 Mbps MEGABITS per second, or MEGABYTES?

jackyht
08-07-2003, 12:51 AM
Hi Jerry

I was the timing is reasonable already, 10-15 is acceptable for a 10MB files...

I think the MBps is referring to megabits not megabytes.... it is similar to the modem speed... it said 56k, it actually shows as 5.6k, 128kb means 12.8 etc etc

hope that helps
jacky

jackyht
08-07-2003, 12:52 AM
sorry, i mean "i think", not "I was" on the 1st sentences

jerry_23
08-07-2003, 12:58 AM
Thanks. Yes, I sort of thought that was how it is too. I just thought it would've transfered quicker than that.

Graham L
08-07-2003, 05:26 PM
Fast is not instantaneous. :D

Get a null modem cable, set up Laplink or DCC, and try a transfer of a 10MB file at 2400 bps. Or even 9600. Or do it on papertape, with a 110 cps (fast) punch, and a 300 cps reader.

You've all been spoiled. :D The fastest file transfers I have ever done was by driving a van with a few 2400ft magnetic tapes in the back.

KiwiTT
08-07-2003, 06:03 PM
Peak utilisation on Ethernet is about 80-90% with 2 PCs and as the number of PCs increase on the segment or hub it reduces to about 40%.

Given that 80% utilisation = 8 Mbits/s or 1 Mbyte/s = 10 seconds for 10 MByte file.

Note there is also preamble, frame headers, tcpip headers and other sorts of headers and checksums depending on the protocol used. This can extend your time from 10 to the 15 seconds you mentioned.

I agree with Graham L. I started file transfer at 300 bps.

cyberchuck
08-07-2003, 10:24 PM
> Peak utilisation on Ethernet is about 80-90% with 2 PCs and as the number of PCs
> increase on the segment or hub it reduces to about 40%.
>
> Given that 80% utilisation = 8 Mbits/s or 1 Mbyte/s = 10 seconds for 10 MByte file.
> Note there is also preamble, frame headers, tcpip headers and other sorts of headers
> and checksums depending on the protocol used. This can extend your time from 10 to
> the 15 seconds you mentioned.

Well said!
Also, don't forget that if you are comparing copying a 10MB file from one PC to another at your house, and then doing the same at a CyberCafe or work, you will find the difference is also due to the Lan's at those venues would most likely be 100mbps...


CyberChuck

jerry_23
08-07-2003, 11:46 PM
OK, so let me get this straight. My 10Mbps card is transferring approx 1 Megabyte per sec?

If this is right, then ok, its just that I always hear people referring to them as ten megaBYTE per sec cards ,which is in fact wrong then isn't it? No wonder I was wondering why it was so slow.

Even at places like Dick Smith they call them Megabyte cards...misleading.

Cheers to all for those words of wisdom.

tweak\'e
09-07-2003, 12:12 AM
10Mb/s cards (10 mega BIT) transfer at roughly 500K/s (varies a bit depepnding on overhead etc). have a look here (http://www.wown.info/j_helmig/netspeed.htm).

Dick Smith have sales people not techs ....and with all salespeople NEVER believe a word they say ;-)

jerry_23
09-07-2003, 12:19 AM
lol, true.

Maybe I should look into these 100 M E G A B I T deals then.

PoWa
09-07-2003, 01:46 AM
Which begs the question, how come you were using 10Mbit cards in the first place? A 100Mbit card is only about $23. ;) You can even get Gigabit cards for a $100+.

Is my maths wrong? but does a 100Mbit card supposedly transfer at 12.5Megabytes/sec??

Someone do the maths :)

jerry_23
09-07-2003, 02:47 AM
the reason I have a 10mbps to begin with is because that is what is integrated on my board.

From what I have learned so far, yes I do believe the 100mbps would equate to roughly 10 Megs per sec.

Oh, and I had also failed to mention right at the start that the download of the 10MB file was through a hub. I have since transfered the same file using a crossover, and it seemed to be a wee bit faster, but only a fraction.

KiwiTT
09-07-2003, 10:13 AM
Get the 100Mbits/s cards. They will probably be full-duplex as well which would significantly increase your throughput if they are directly connected.

Graham L
09-07-2003, 01:14 PM
If you have a careful look at the card, you'll see a 20MHz crystal oscillator. That's the 2X clock for a 10 Mbps 10BaseX Ethernet tranceiver.

If you've got a working system why change? 10-15 seconds for a big file isn't slow. There is also the problem that some of the cheap 100 Mbps cards don't work. :D (Or they nearly work ... which is worse.)

jerry_23
09-07-2003, 01:14 PM
OK, I need to know, how do i go about getting this 100Mbps thing. I made my way into the properties of the card that is installed now, and changed a setting from Automode to 100 full mode. The problem there was that it disconnected the card until I reset it to what it was.

Question: Can the card I have now run at 100 by simply changing this setting properly, or do I have to actually buy another card? If so, what does the 100 in '10/100' mean?

KiwiTT
09-07-2003, 02:02 PM
Not sure, but you may need to make sure you have both cards configured the same, if they are directly connected. Before you connect them. I assume you have cat 5, cross-over cable

If you go through your 10Mb hub, it will also disconnect. You need a 100mbs switch for full duplex if you want to use a device between them. DSE sell these.

jerry_23
09-07-2003, 02:36 PM
Ahhh yes, Currently, I am going through a dse 5 port hub so thats probably why. Also, the card on the other machine does not have the same speed settings to set to 100, so it all makes sense.

The reason I want more speed, (stop thinking about the 10Meg file for a moment) is that my original plan is to transfer 60 GB before I reformat.

That damn stupid hub!

KiwiTT
09-07-2003, 03:43 PM
I can see your reasoning.

60GB would take over 16 hours. At 100 mb it will take less than 2 hours.

Graham L
09-07-2003, 03:58 PM
Why not install the destination disk in the source machine, and do a 60 GB copy? :D

To run 100BaseT you need 100MHz rated components all the way ... hubs/switches/cables ... as well as the cards. Most of the 10/100 cards autodetect and work at the best speed, though you should be able to make them use one rate. Full duplex does not double the 100 MHz to 200 ; there is still a 100 MHz maximum rate in each direction. It's just that if cards will handle it, transfers can go both ways at once.