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heni72847
14-06-2007, 12:03 AM
had wireless setup at home for ages
but only used it for internet and not data transfer

today tried to copy a file and notice it can only reach around 360kb/s
this is copying a file on my desktop through window share onto a notebook through wifi
my wireless is connected at 11Mbps not 5 or 1 (yea it's b not g)
so 11Mbps should give me around 1.3Mbyte/s
so what I'm getting is 2.8Mbps.. not even half of 11

I've read somewhere that out of 11Mbps you can only use 5.5Mbps..no idea if this is true
but I'm getting slower than that

I've also tried getting two notebooks to copy across wifi
and the speed they get sums up to around 360 too
trying to read and write is even worse..I don't think full-duplex is working or something

so yea..anyone can explain?
all these speed test done when the notebook is in the same room as the access point.. so not some bad signal problem

Renmoo
14-06-2007, 12:16 AM
Possible interference due to other electromagnetic-wave emitting electrical appliances, perhaps? (e.g. microwave oven)

Have you tried placing the laptop directly just beside the access point and see what speeds are you getting?

Cheers :)

heni72847
14-06-2007, 12:33 AM
see the weird thing is that on the notebook it says I'm connected at 11Mbps
and yes I've placed my notebook next to the AP and get same results

sometimes if I do take my notebook too far away from the AP speed do drop to 5Mbps but that is not what I'm concerned about right now

oh I've also scanned and looked at the channels my neighbours are using and avoided channels close to theirs
I've got no wireless telephone and no pie cooking in microwave

sal
14-06-2007, 01:08 AM
Is Vista involved here (http://support.microsoft.com/default.aspx/kb/931770)?

heni72847
14-06-2007, 01:08 AM
nope just XP

motorbyclist
14-06-2007, 01:52 AM
um, are you getting your BYTES confused with BITS?

a common misconception is Mbps is the same thing as MBps, and they are not. the upper case B represents Bytes and the lower case b resprsents bits.

8bits make 1 Byte, so 11Mbps = (11/8)MBps = 1.375MBps

but that isn't as low as 0.360MBps - weird, even 5.5Mbps comes to 0.688MBps

remember wireless is prone to interference; any high tension power lines overhead? cellphone? microwave oven? cordless phone? metallic objects? another possibility is that the bandwidth is being used by other processes....

motorbyclist
14-06-2007, 01:53 AM
actually, after a re-read of your post i think you can tell the difference, owell - i forgot to account for the 1024 and used 1000 between kilo and mega etc anyway

apsattv
14-06-2007, 03:42 AM
Look in the wifi device settings make sure they are matched? packet size turbo etc? tx burst and other options like tcp window.

heni72847
14-06-2007, 08:27 AM
no turbo or burst on this AP
it is a ZyAIR B-1000 so it can only deliver 802.11b
any settings I can see is related to security

I'm using total commander to copy files across so I can get a speed reading
is there any other way to see the speed? although I think total commander's values are not wrong..
also does window file share got something to do with the slow speed?

tweak'e
14-06-2007, 11:15 AM
don't forget a 10Mb network max's at 550kB/s, then take into account of overheads ie windows fileshareing etc and interference etc, its not uncomman to be slower.

motorbyclist
14-06-2007, 12:00 PM
try netmeter, it's pretty good

http://www.metal-machine.de/readerror/

i'm still using 0.9.9.9beta and it's pretty good, tells you exactly what you want to know and in the units you want to see it. plus transparency, always on top and click-through features:D

heni72847
14-06-2007, 05:42 PM
I've always thought 10Mbps network gives you max of 1.25Mbyte/s
guess I was wrong then..

Graham L
14-06-2007, 05:51 PM
actually, after a re-read of your post i think you can tell the difference, owell - i forgot to account for the 1024 and used 1000 between kilo and mega etc anyway What 1024? In bit speeds, all the numbers are decimal. :groan:

Anyway, everyone should now be using the proper prefixes to avoid all ambiguity and confusion. kibi = 1024, kilo = 1000 . :cool:

tweak'e
14-06-2007, 07:06 PM
I've always thought 10Mbps network gives you max of 1.25Mbyte/s
guess I was wrong then..
thats more likly 100Mb/s speed.

there was a good networking site that explained why it is like that.

motorbyclist
15-06-2007, 12:33 PM
I've always thought 10Mbps network gives you max of 1.25Mbyte/s
guess I was wrong then.. i think you're right, remember my original "quote" was for 11MBps


What 1024? In bit speeds, all the numbers are decimal. :groan:

Anyway, everyone should now be using the proper prefixes to avoid all ambiguity and confusion. kibi = 1024, kilo = 1000 . :cool:

what? as i understand it 10Mbps as the ISPs and networking hardware ppl sell it is 10/8 * 1024 * 1024 = 1310720Bytes per second, or dividing back again by 1024 and again by 1024 gives 1.25MBps (which, as many of you can see is just 10/8, so ignore my post about not converting it:blush:)

the same applies if you do it in decimal - you still get 1.25

why you'd do it in decimal is beyond me, except i see hard drive manufacturers do like to - making the average user think they're buying more than you really are

Graham L
15-06-2007, 08:34 PM
Measurements which are counts of events (clock cycles, bits transmitted) normally use decimal.

One bit per second is one bit per second. 1 kilobit per second is 1000 bits per second. 1 megabit per second is 1000 times that. 10 Mbps, the "standard" Ethernet speed is 10 million (decimal) bits per second. It has always been that. It's decimal. This is all based on the old communications standards, which go back many years. 300 bps is 300 (decimal) bits per second. 2400 bits per second is 2400 (decimal).

I'd do it in decimal because that's the natural human notation. 1 Mbps is 1,000,000 bps. "ISPs and networking hardware" use that unit of measurement. (By the way, 1 024 x 1 024 = 1 048 576 ).

Computer clock speeds are measured in Hz (cycles per second) 1 kHz is 1000 cles per second, 1 MHz is 1000000 cycles per second.

Memory size has been expressed using the powers of 2 units, because the hardware was suited to that. But that notation came about mostly because that's the way the memory addresses were displayed in assemply language software listings (except for the few decimal computers like the 1620).

Disk sizes have often used the IBM "Mbyte" unit: 1000*1024. Now many manufacturers use the 1024*1024 or the 1000*1000 "mega" to give the most impressive numbers. :(

This has caused a lot of confusion. Why would you confuse yourself by using 1024? :D

heni72847
15-06-2007, 10:03 PM
ha.. going OT now but I don't care

um..I think the confusion is how...
1024 bytes is 1 kilobyte
1024 kilobyte is 1 megabyte
and 1024 megabyte is 1 gigabyte
for historic or legacy units anyway (what wiki calls it)

but 1000 meter is 1 kilometer and 1000 kilometer is 1 megameter etc..
er..sounds weird but if you read it while thinking scientific notations then sorta make sense

but if you just apply the prefix of kilo, mega, or giga like you usually do onto byte..sometimes the numbers just go all funny
I guess that's why Mebibyte came into place to stop the confusion..but imho it must made people more confused..

godfather
15-06-2007, 11:00 PM
You need to consider the the 11 Mb/s is duplex. 5.5 each direction...

heni72847
16-06-2007, 09:35 AM
is it the duplex problem or something else?
because for example from dse site the description for its 10/100 NIC (XH8265)

"...full-duplex operation for up to 200Mbps bandwidth"

um..confusing

trinsic
16-06-2007, 03:08 PM
I get sort of the same problem. I can download at 400+KB/s online but through LAN it goes at 30KB/s. Router is accepting the required ports. Firewall is off. But no joy :(

But I a using 802.11g

heni72847
16-06-2007, 08:02 PM
I only notice this problem when I was playing acc encoded files across my wlan (which uses like 5Kb/s)
and someone was downloading through wlan too (prob around 250+Kb/s)
and my music started to lag and skip and I was amazed at how slow my wifi actually was..