Throughput vs link speed

I have posted a few times looking for help streaming video over my 802.11g
net at home.
I finally found an app the measures throughput Qcheck.
Here is what I am seeing.

It seems that between my wired and the 2nd floor MCE (the farthest leg) I am
getting around 10mbps occasionally single digits.
Between the 1st floor and 2nd floor (both wireless it is closer to 1-3 mbps.

However the link speed on the twoo wireless PC is is 54.

What is the difference between link speed and throughout? Why is there such
a gap?

On Sun, 8 Feb 2004 08:05:15 -0500, "Robert Desel" <(E-Mail Removed)>
wrote:

>I have posted a few times looking for help streaming video over my 802.11g
>net at home.
>I finally found an app the measures throughput Qcheck.
>Here is what I am seeing.
>
>It seems that between my wired and the 2nd floor MCE (the farthest leg) I am
>getting around 10mbps occasionally single digits.
>Between the 1st floor and 2nd floor (both wireless it is closer to 1-3 mbps.
>
>However the link speed on the twoo wireless PC is is 54.
>
>What is the difference between link speed and throughout? Why is there such
>a gap?
>

Link speed is the fastest possible transfer rate in one direction.
Throughput is the rate at which data is actually transfered.

The difference can be from protocol overhead (up to 10%), the fact that
WiFi is only half duplex, so download bandwidth will be reduced by uploaded
data (which is not very much on a streaming video), Error
retrys/retransmissions which normally mean low signal strength,
interference, etc.

On your streaming, is your source wired or wireless. If it is wireless to
wireless, that cuts the potential throughput in half because a packet goes
from the source to the AP where it is buffered and then retransmitted to
the destination. Are you streaming to all three computers at the same time?
If so, packets to each computer are buffered and transmitted separately,
which cuts down the throughput by 3, and again if the source is also
wireless, that reduces the throughput even further.

Hope this helps

JT

That is a big help
Two are wireless and there fore cut in Half)
One is wired.
I am rarely streaming to all three
The lesson I think is to try to most or all of my recorded TV on the wired
server
THANKS!!!
"JT" <datacare@www> wrote in message
news:(E-Mail Removed) s.com...
> On Sun, 8 Feb 2004 08:05:15 -0500, "Robert Desel" <(E-Mail Removed)>
> wrote:
>
> >I have posted a few times looking for help streaming video over my
802.11g
> >net at home.
> >I finally found an app the measures throughput Qcheck.
> >Here is what I am seeing.
> >
> >It seems that between my wired and the 2nd floor MCE (the farthest leg) I
am
> >getting around 10mbps occasionally single digits.
> >Between the 1st floor and 2nd floor (both wireless it is closer to 1-3
mbps.
> >
> >However the link speed on the twoo wireless PC is is 54.
> >
> >What is the difference between link speed and throughout? Why is there
such
> >a gap?
> >
>
> Link speed is the fastest possible transfer rate in one direction.
> Throughput is the rate at which data is actually transfered.
>
> The difference can be from protocol overhead (up to 10%), the fact that
> WiFi is only half duplex, so download bandwidth will be reduced by
uploaded
> data (which is not very much on a streaming video), Error
> retrys/retransmissions which normally mean low signal strength,
> interference, etc.
>
> On your streaming, is your source wired or wireless. If it is wireless to
> wireless, that cuts the potential throughput in half because a packet goes
> from the source to the AP where it is buffered and then retransmitted to
> the destination. Are you streaming to all three computers at the same
time?
> If so, packets to each computer are buffered and transmitted separately,
> which cuts down the throughput by 3, and again if the source is also
> wireless, that reduces the throughput even further.
>
> Hope this helps
>
> JT