108Mbps vs. 54Mbps

Hello guys. I'm fairly new to wireless tech, but have set up a few
basic systems for some of my customers. I have just purchased a laptop
for my wife. The computer has Intel® PRO/Wireless 2200BG internal
network card. I purchased a D-Link DI-624 108 Mbps High Speed 802.11g
Wireless router. The router was DOA and the store I got it from is an
hour away. I ran down to the local Radio Shack and got at Linksys
WRT54G 2.4Ghz 802.11g wireless router. My question is if it is as fast.
It claims a speed of 54Mbps or half as fast as the D-Link. Is true that
my connection speed is half as fast or is the issue range, and finally
is the internal card capable of receiving 108Mbps? Thank you guys for
clearing some of this up for me.

Mad_Unit wrote:

> Hello guys. I'm fairly new to wireless tech, but have set up a few
> basic systems for some of my customers. I have just purchased a laptop
> for my wife. The computer has Intel® PRO/Wireless 2200BG internal
> network card. I purchased a D-Link DI-624 108 Mbps High Speed 802.11g
> Wireless router. The router was DOA and the store I got it from is an
> hour away. I ran down to the local Radio Shack and got at Linksys
> WRT54G 2.4Ghz 802.11g wireless router. My question is if it is as fast.
> It claims a speed of 54Mbps or half as fast as the D-Link. Is true that
> my connection speed is half as fast or is the issue range, and finally
> is the internal card capable of receiving 108Mbps? Thank you guys for
> clearing some of this up for me.
>


the 108Mbps of your d-link router only works with a d-link 108mbps
enabled wifi card.
thus if your wifes laptop uses its internal wifi card, it will work at
54Mbps mode nomatter d-link, linksys or any other 802.11g router.

On 16 Feb 2005 05:55:30 -0800, "Mad_Unit" <(E-Mail Removed)>
wrote:

>Hello guys. I'm fairly new to wireless tech, but have set up a few
>basic systems for some of my customers. I have just purchased a laptop
>for my wife. The computer has Intel® PRO/Wireless 2200BG internal
>network card. I purchased a D-Link DI-624 108 Mbps High Speed 802.11g
>Wireless router. The router was DOA and the store I got it from is an
>hour away. I ran down to the local Radio Shack and got at Linksys
>WRT54G 2.4Ghz 802.11g wireless router. My question is if it is as fast.
>It claims a speed of 54Mbps or half as fast as the D-Link. Is true that
>my connection speed is half as fast or is the issue range, and finally
>is the internal card capable of receiving 108Mbps? Thank you guys for
>clearing some of this up for me.

The "standard" for the 802.11g is 54Mbps. To get beyond that each
manufacturer uses different technology to "enhance" the signal. No two
manufacturers use the same technology to do it.
You could have bought a WRT54GS and gotten the 108Mbps but ONLY with
another Linksys card that supports "speedboost".

"Mad_Unit" <(E-Mail Removed)> wrote in news:1108562129.985780.18290
@g14g2000cwa.googlegroups.com:

> My question is if it is as fast.
> It claims a speed of 54Mbps or half as fast as the D-Link. Is true that
> my connection speed is half as fast or is the issue range, and finally
> is the internal card capable of receiving 108Mbps?

You'll need a Dlink 108mbps card to get the full speed.

Also, with WiFi, I doubt you'll get probably 30 - 40% of the rated speed.
So with a 54mbps AP, expect about ~20 - 25mbps. With a 108mbps AP, you'll
get about 40 - 50mbps. Don't expect to hit 108mbps, you'll need a wired LAN
for that.

--
Lucas Tam ((E-Mail Removed))
Please delete "REMOVE" from the e-mail address when replying.
http://members.ebay.com/aboutme/coolspot18/

The data rates for 802.11a and 802.l1g that are higher than 54 Mbs are
achieved by manufacturer proprietary schemes. To take advantage of the
proprietary schemes, both the Access Point and Client hardware will have to
be from the same manufacturer and capable of their manufacturer-specific
"turbo" scheme. Some manufacturers claim upwards of 72 Mbs, while others
(D-Link) claim upwards of 108 Mbs. I'm using D-Link stuff that claims 108
Mbs for both 802.11a and 802.11g. Of course, the actual throughput is no
where near 108 Mbs. These claims are based on the max rate possible (in
theory) in RF clean lab conditions.

Even though the "turbo" doesn't come close to what it's claimed, I've found
that it does give about 30 percent boost over vanilla 802.11a with my D-Link
stuff, which I'm happy with. Can't say about 802.11g as I don't have any
client hardware 802.11g.

Keep in mind that the proprietary "turbo" schemes, while giving some modest
"boost", will also introduce new limitations. With "turbo" enabled, your
wireless range is somewhat reduced. Can't speak for the other
manufacturers, but with D-Link using "turbo" requires that your center
frequency for "turbo" to be on channel 6 -- which may be more prone to
interference. Also, (at least with D-Link), you have two options for
"turbo" that are either dynamic or static. With "dynamic turbo", if you
have a "turbo enabled" connection established and another connection
(non-turbo) is established, then everything will drop back to vanilla
802.11a/g. With "static turbo", only hardware capable of "turbo enhanced"
connections will be permitted to connect.

Cheers,
-ES

On Wed, 16 Feb 2005 15:10:50 +0100, Ali Babba <(E-Mail Removed)>
wrote:

>the 108Mbps of your d-link router only works with a d-link 108mbps
>enabled wifi card.
>thus if your wifes laptop uses its internal wifi card, it will work at
>54Mbps mode nomatter d-link, linksys or any other 802.11g router.

That statement is not quite true. You do not necessarily need a DLink
108mbps enabled wifi card to obtain such speeds in conjunction with
the DI-624 wireless router. I am able to obtain such speeds using my
Netgear WG511T card when used with the DI-624 and the DWL-2100AP.

I just recently bought a Linksys WRT54GS like you talk about here, and
the matching wireless card for one of my computers. For the first two weeks
of operation, I was getting 125 Mbps showing up on the network monitor. It
rained ( and thunder and lightening) for the first time since I've owned the
setup yesterday, and the connection speed dropped to 54Mbps. I changed the
transmit channels, and the signal speed went back up, but this morning, it's
back to 54Mbps. The access point and the computer are less than 3 feet
apart, with a half-wall spearating them. Anyone have any ideas?



"f/fgeorge" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On 16 Feb 2005 05:55:30 -0800, "Mad_Unit" <(E-Mail Removed)>
> wrote:
>
>>Hello guys. I'm fairly new to wireless tech, but have set up a few
>>basic systems for some of my customers. I have just purchased a laptop
>>for my wife. The computer has Intel® PRO/Wireless 2200BG internal
>>network card. I purchased a D-Link DI-624 108 Mbps High Speed 802.11g
>>Wireless router. The router was DOA and the store I got it from is an
>>hour away. I ran down to the local Radio Shack and got at Linksys
>>WRT54G 2.4Ghz 802.11g wireless router. My question is if it is as fast.
>>It claims a speed of 54Mbps or half as fast as the D-Link. Is true that
>>my connection speed is half as fast or is the issue range, and finally
>>is the internal card capable of receiving 108Mbps? Thank you guys for
>>clearing some of this up for me.
>
> The "standard" for the 802.11g is 54Mbps. To get beyond that each
> manufacturer uses different technology to "enhance" the signal. No two
> manufacturers use the same technology to do it.
> You could have bought a WRT54GS and gotten the 108Mbps but ONLY with
> another Linksys card that supports "speedboost".
>

"SomeGuy" <(E-Mail Removed)> wrote in message
news:k4CdncO3FY6C7NjfRVn-(E-Mail Removed)...
> I just recently bought a Linksys WRT54GS like you talk about here, and
> the matching wireless card for one of my computers. For the first two
weeks
> of operation, I was getting 125 Mbps showing up on the network monitor.
It
> rained ( and thunder and lightening) for the first time since I've owned
the
> setup yesterday, and the connection speed dropped to 54Mbps. I changed
the
> transmit channels, and the signal speed went back up, but this morning,
it's
> back to 54Mbps. The access point and the computer are less than 3 feet
> apart, with a half-wall spearating them. Anyone have any ideas?

As someone else replied, the data rates over 54 Mbs are usually proprietary
mechanisms. I'm using D-Link and not overly familiar with Linksys, but
there are some settings with D-Link that cause what you are seeing. With
D-Link, on the AP's that are capable of their proprietary 108 Mbs "turbo"
mode there is an option for the turbo to be either dynamic or static. If
it's set to "dynamic", then connections can be made to the AP with turbo
enabled or disabled on the client's end. If any client connects to the AP
without turbo in use, then turbo is disabled for all connected clients --
regardless if they can support it or not. Also, the signal has to be
relatively strong in order for turbo to be used. If it is set to "static",
then only clients capable of "turbo" are permitted to connect. If there are
no "non-turbo" clients connected, check the signal level when it "drops" to
54 Mbs. May want to try moving the two as well. It could be possible that
three feet apart, even through the half-way, is too close.

As for the true data throughput, 108/125 Mbs (and even 54 Mbs) are more
marketing numbers than anything else. Thats the theoretical max throughput
if used in an RF clean lab. Real world use, of course, is much different.
Do a google for a program called "NetPerSec". Its a small little program
that will give the actual data throughput. If you can, try to hunt down
version 1.1 -- as that version not only gives current data throughput, max
data throughput, but also an average. Unfortunetly, I don't remember the
exact location that I found this version at (took some digging) other than
it was on an Italian website.

Cheers,
-Eric

> "SomeGuy" <(E-Mail Removed)> wrote in message
> news:k4CdncO3FY6C7NjfRVn-(E-Mail Removed)...
> I just recently bought a Linksys WRT54GS like you talk about
> here, and the matching wireless card for one of my computers. For
> the first two weeks of operation, I was getting 125 Mbps showing up
> on the network monitor.
> It
> rained ( and thunder and lightening) for the first time since I've
> owned the setup yesterday, and the connection speed dropped to
> 54Mbps. I changed the transmit channels, and the signal speed went
> back up, but this morning, it's back to 54Mbps. The access point
> and the computer are less than 3 feet apart, with a half-wall
> spearating them. Anyone have any ideas?


I forget the exact reasons/setting, but sure somebody here can tell you what
it is. While the link starts out at the highest speed, the first time it
gets a certain number of errors, it drops to a lower speed to try and keep
on going error free. But it never increases the speed again. I have heard
people say that after a while it will even keep going down and down in
speed, until they reconnect/restart.