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LAN speed ?

.... and we shift hundreds of GBs of media file data at work every day over gigabit connections using all manner of cable standards and lengths (Cat 5, 5E, 6).
 
Base-T Ethernet is not an adaptive technology (although it might fall back to a lower standard). The only means to overcome a bad connection is to resend whole packets (handled by the TCP/IP protocol, not the MAC layer) so if there was a problem the data rate would be noticeably crippled.

Besides, my reference to Cat5 was not specific. The point was that Gigabit uses all eight wires whereas 10/100Base-T only uses four of them.
 
Hey, BH and prpr agreeing on something, that must be a first, I think I'll apply for a job at the United Nations :)
 
Black Hole said:
The point was that Gigabit uses all eight wires whereas 10/100Base-T only uses four of them.
Click to expand...

To be pedantic (what me?) 100bTX uses only four wires. Some other 100bT standards such as 100bT4 used eight.


Posted on the move; please excuse any brevity.
 
My old Cat5 cables only have four wires, whereas my Cat5E and Cat6 cables have eight wires.
 
Never heard of that before.

From Wikipedia:
Each of the four pairs in a Cat 5 cable has differing precise number of twists per metre to minimize crosstalk between the pairs. Although cable assemblies containing 4 pairs are common, Category 5 is not limited to 4 pairs. Backbone applications involve using up to 100 pairs. This use of balanced lines helps preserve a high signal-to-noise ratio despite interference from both external sources and crosstalk from other pairs.
Click to expand...
 
I have some 2 pair Cat5e cable (just green and orange pairs). Useful for running 100Mb/s connections round rooms under carpet as it's quite thin.

I've also see 2 pair Cat5e cables supplied with cheap routers.. There's no problem with them in general.
 
My 2-pair Cat5 cables were supplied with my 85Mbps HomePlugs, which have recently been taken out of service and replaced with 500Mbps versions.
 
I have tested the speed with a large upload. First part I used the normal Lan wired connection 10/100 with Cat5 cable, the second part of the upload of the same large file with a wired 1Gb Cat5 connection. I just disconnected the cable for the 10/100 and connected it to the 1Gb connection without stopping the data transfer which resumed. The result:

10/100 with Cat5 cable:- Network Utilisation average 25%; connection speed 100Mbps

1Gb with Cat5 cable:- Network Utilisation average 2.3%; connection speed 1Gbps

I don't know how to check the actual speed of the data transfer and don't know if the figures quoted are meaningful in that respect.

I normally use a wireless connection but very occasionally when I have a large file to upload I use a cable. It is just a question of which is best if any and curiosity.

Can anyone enlighten me?
 
take a known file size. copy it with one, and the other and time how long it takes in seconds.

25 utilsation of 100'bit is about 25'bit naturally = around 2:5Mbytes a second. similar to your gigabit frankly....
 
So as everyone thought no improvement. Ok I am happy with that knowledge thank you.

Now you may continue in my thread discussing various cables. ;)

Edit: May be of interest:

Wireless transfer of the same file: Network Utilisation 51% Link speed 54Mbps

This changes to 62% and 24Mbs at times lately
 
Yep... and 50% ish of 54Mbits is about the same too... if you are on wireless or wired each packet goes into your switch then gets pushed back out at the other port at the speed it needs so the connection from you to switch as long as higher or the same as the other device then speed will be the same...

And cables.... for a short patch cable cat5/5e/6 - it's just 8 bits of wire. Yes different numbers of twists etc. but still 8 bits of wire... I don't know the figures (ore really care!) but doubt it is an issue until you get into 10's of metres. Lots of people don't even know the proper wiring layout for the pairs and get away with bodged cables.
 
I did as you suggested - transfer a file:

wireless; 75 seconds

10/100; 30 seconds

1Gbps; 30 seconds as near as dam it.

Btw, the file was being sent to a Raspberry Pi.

Whilst on the subject of speed

I don't suppose there is anything that can be done to improve the recipients speed?
 
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