Is there a wireless router or AP that can handle this???!!

I am very confused by all the talk about max throughput, etc. I even
call the vendors technical sales support on 3Com and D-Link and I get
widly different answers. Even when I call D-Link back and talk to a
different tech sales rep I get a different answer.

Here is my scenario...

I have a wireless computer lab with 24 computers. The students use
the computers to connect to a website that is very heavy on Flash and
Shockwave (it is an interactive learning website). We are told, by
the makers of the website, that each user requires the capability of
60Kb/sec in order to run the flash or shockwave files. Now based on
this, is there a wireless router or ap that can handle this kind of
load with 24 computers all downloading 60+Kb/sec???!!

D-Link originally told me no. Then another sales rep told me their
DWL-1000AP product, and to top it all off, 3Com rep told me that there
wasn't a router/ap product available in the market to handle that type
of bandwidth usage over so many users. Who is right, who is wrong??!!
Can someone explain, and give me their insight?

Thanks in advance,
Sean

Assuming you mean 60 kilobits/sec/station, the total bandwidth is 1.44
Megbits/sec. It's hard to believe an 802.11b router can't handle that. But -
if you mean 60 kiloBYTES/sec, then we're talking 11.52 Megabits/sec total,
clearly out of the question for 802.11b. If it supports a turbo mode, then
the nominal bandwidth probably stretches to 22 Megabits/sec, but you still
may not get a full 11 Megabits/sec in reality. But - an 802.11g, router
should easily support this.

The comment by the 3Com rep suggests that the problem is switching over a
large number of users. This makes sense to me. An AP intended for SOHO or
small business is relatively inexpensive. It probably does store-and-forward
to make bridging and filtering easy, which means memory copies. This adds
per-port-latency which means that if you have more than a small number of
clients concurrently active, the actual available bandwidth may take a
nosedive.

I'm sure there are expensive routers that switch over a high-speed internal
bus and do all of the data manipulation in hardware, but these will cost
thousands.

"Sean" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> I am very confused by all the talk about max throughput, etc. I even
> call the vendors technical sales support on 3Com and D-Link and I get
> widly different answers. Even when I call D-Link back and talk to a
> different tech sales rep I get a different answer.
>
> Here is my scenario...
>
> I have a wireless computer lab with 24 computers. The students use
> the computers to connect to a website that is very heavy on Flash and
> Shockwave (it is an interactive learning website). We are told, by
> the makers of the website, that each user requires the capability of
> 60Kb/sec in order to run the flash or shockwave files. Now based on
> this, is there a wireless router or ap that can handle this kind of
> load with 24 computers all downloading 60+Kb/sec???!!
>
> D-Link originally told me no. Then another sales rep told me their
> DWL-1000AP product, and to top it all off, 3Com rep told me that there
> wasn't a router/ap product available in the market to handle that type
> of bandwidth usage over so many users. Who is right, who is wrong??!!
> Can someone explain, and give me their insight?
>
> Thanks in advance,
> Sean

"gary" <(E-Mail Removed)> wrote...
> Assuming you mean 60 kilobits/sec/station, the total bandwidth is 1.44
> Megbits/sec. It's hard to believe an 802.11b router can't handle that.
But -
> if you mean 60 kiloBYTES/sec, then we're talking 11.52 Megabits/sec
total,
> clearly out of the question for 802.11b. If it supports a turbo mode,
then
> the nominal bandwidth probably stretches to 22 Megabits/sec, but you
still
> may not get a full 11 Megabits/sec in reality. But - an 802.11g, router
> should easily support this.

I think you need to recheck you math...

Seems you are overscaling by at least a factor of 10...

Sean wrote:

> I am very confused by all the talk about max throughput, etc. I even
> call the vendors technical sales support on 3Com and D-Link and I get
> widly different answers. Even when I call D-Link back and talk to a
> different tech sales rep I get a different answer.
>
> Here is my scenario...
>
> I have a wireless computer lab with 24 computers. The students use
> the computers to connect to a website that is very heavy on Flash and
> Shockwave (it is an interactive learning website). We are told, by
> the makers of the website, that each user requires the capability of
> 60Kb/sec in order to run the flash or shockwave files. Now based on
> this, is there a wireless router or ap that can handle this kind of
> load with 24 computers all downloading 60+Kb/sec???!!
>
> D-Link originally told me no. Then another sales rep told me their
> DWL-1000AP product, and to top it all off, 3Com rep told me that there
> wasn't a router/ap product available in the market to handle that type
> of bandwidth usage over so many users. Who is right, who is wrong??!!
> Can someone explain, and give me their insight?
>
> Thanks in advance,
> Sean

60 KB/s * 24 = 1.44 MB/s ~= 12 Mb/s, which wildly exceeds the peak
download bandwidth of typical broadband, whether cable or DSL.

If you can't get it down the fat pipe, it doesn't much matter how
inefficiently the router shares the bandwidth amongst the 24 skinny
(virtual) pipes; and, 802.11 protocol is far from efficient.
--
Cheers, Bob

"Bob WIllard" <(E-Mail Removed)> wrote...
> Sean wrote:
>
> > I am very confused by all the talk about max throughput, etc. I even
> > call the vendors technical sales support on 3Com and D-Link and I get
> > widly different answers. Even when I call D-Link back and talk to a
> > different tech sales rep I get a different answer.
> >
> > Here is my scenario...
> >
> > I have a wireless computer lab with 24 computers. The students use
> > the computers to connect to a website that is very heavy on Flash and
> > Shockwave (it is an interactive learning website). We are told, by
> > the makers of the website, that each user requires the capability of
> > 60Kb/sec in order to run the flash or shockwave files. Now based on
> > this, is there a wireless router or ap that can handle this kind of
> > load with 24 computers all downloading 60+Kb/sec???!!
> >
> > D-Link originally told me no. Then another sales rep told me their
> > DWL-1000AP product, and to top it all off, 3Com rep told me that there
> > wasn't a router/ap product available in the market to handle that type
> > of bandwidth usage over so many users. Who is right, who is wrong??!!
> > Can someone explain, and give me their insight?
> >
> > Thanks in advance,
> > Sean
>
> 60 KB/s * 24 = 1.44 MB/s ~= 12 Mb/s, which wildly exceeds the peak
> download bandwidth of typical broadband, whether cable or DSL.
>
> If you can't get it down the fat pipe, it doesn't much matter how
> inefficiently the router shares the bandwidth amongst the 24 skinny
> (virtual) pipes; and, 802.11 protocol is far from efficient.
> --
> Cheers, Bob

Sounds like they need a local, caching proxy server...

"Graham in Melton" <(E-Mail Removed)> wrote in message
news:BBC5AD4D.16C1D%(E-Mail Removed)...
> >
> > Sounds like they need a local, caching proxy server...
> >
> Or someone to redesign the website more like - Flash movies do not take
> 60k/s unless they are transmitting unnecessarily large files etc all the
> time.

Copy the site to CDROM, and make a copy for each machine?

On 29/10/03 5:24 pm, in article
jMSnb.63463$(E-Mail Removed), "Darrel Toepfer"
<(E-Mail Removed)> wrote:

> "Bob WIllard" <(E-Mail Removed)> wrote...
>> Sean wrote:
>>
>>> I am very confused by all the talk about max throughput, etc. I even
>>> call the vendors technical sales support on 3Com and D-Link and I get
>>> widly different answers. Even when I call D-Link back and talk to a
>>> different tech sales rep I get a different answer.
>>>
>>> Here is my scenario...
>>>
>>> I have a wireless computer lab with 24 computers. The students use
>>> the computers to connect to a website that is very heavy on Flash and
>>> Shockwave (it is an interactive learning website). We are told, by
>>> the makers of the website, that each user requires the capability of
>>> 60Kb/sec in order to run the flash or shockwave files. Now based on
>>> this, is there a wireless router or ap that can handle this kind of
>>> load with 24 computers all downloading 60+Kb/sec???!!
>>>
>>> D-Link originally told me no. Then another sales rep told me their
>>> DWL-1000AP product, and to top it all off, 3Com rep told me that there
>>> wasn't a router/ap product available in the market to handle that type
>>> of bandwidth usage over so many users. Who is right, who is wrong??!!
>>> Can someone explain, and give me their insight?
>>>
>>> Thanks in advance,
>>> Sean
>>
>> 60 KB/s * 24 = 1.44 MB/s ~= 12 Mb/s, which wildly exceeds the peak
>> download bandwidth of typical broadband, whether cable or DSL.
>>
>> If you can't get it down the fat pipe, it doesn't much matter how
>> inefficiently the router shares the bandwidth amongst the 24 skinny
>> (virtual) pipes; and, 802.11 protocol is far from efficient.
>> --
>> Cheers, Bob
>
> Sounds like they need a local, caching proxy server...
>
Or someone to redesign the website more like - Flash movies do not take
60k/s unless they are transmitting unnecessarily large files etc all the
time.

If it is 60kBytes and not 60kbits, then that the equivalent of a single
512kADSL line per user - nobody designs to that spec do they ?

The OP seems to have been confused by the difference between a ROUTER and a
broadband interface - given a large server located locally, then it is
possible (use Gig ethernet to connect them all to the same router and server
for example) but "online" across the internet, is possible but only if you
have seriously big fat pipes.

Superjanet in the UK could cope for student online in some halls for
example, but once into the public side of the world, as you say, no.

"Enkidu" <(E-Mail Removed)> wrote...
> "Graham in Melton" <(E-Mail Removed)> wrote...
> > >
> > > Sounds like they need a local, caching proxy server...
> > >
> > Or someone to redesign the website more like - Flash movies do not
take
> > 60k/s unless they are transmitting unnecessarily large files etc all
the
> > time.
>
> Copy the site to CDROM, and make a copy for each machine?

"I have a wireless computer lab with 24 computers."

Guess you missed that point? A local cache would allow the "wiress"
network function as designed, given the limited pipe that they have
feeding it...

In article <TzTnb.63483$(E-Mail Removed)>,
Darrel Toepfer <(E-Mail Removed)> wrote:
:"Enkidu" <(E-Mail Removed)> wrote...
:> Copy the site to CDROM, and make a copy for each machine?

:"I have a wireless computer lab with 24 computers."

:Guess you missed that point?

How so? Is 'wireless computer' inherently incompatible with 'CDROM' ?
--
Rump-Titty-Titty-Tum-TAH-Tee -- Fritz Lieber

Since this is an interactive learning website, I assumed that it would be
locally-provided over fast Ethernet. If it is to be accessed via the
Internet, then the suggestion about a local caching site is probably the
best solution for the WAN side.

As everybody agrees, 802.11b can't handle it. 11.5 Mbps - this is the
correct number - is about 20% of the nominal bandwidth of an 802.11g
network. So, you'd think it would be okay on g. But, as someone else
mentioned, 802.11 networks don't necessarily behave nicely with multiple
users. For one thing, any single station that gets a weak signal because of
distance from AP, reflection problems, whatever, could drop to a lower rate
and pull down the whole net with it. Even if all the stations maintain the
nominal rate of 54Mbps for each transmission, with 24 users it's not
entirely clear how much time will be wasted backing off and retrying with
larger windows. Again, 20% of nominal bandwidth "sounds" low, but is it? One
user could easily sustain 11.5Mbps - but could you really chop it up among
24 users? You might consider enabling RTS/CTS for this kind of load.

I also wonder if low-cost SOHO routers can internally handle this many users
at this rate, especially considering this application requires bridging
between Ethernet and 802.11 ports, which means exchanging 802.3/802.11 frame
wrappers - if it's done to a mcmory copy by one processor, then the delay
for each port is proportional to the number of active ports.

There are APs out there that support load-balancing, for example the Proxim
Orinoco line. They cost more, but that might be the way to go for this kind
of load. Having two or more APs also reduces the risk of one weak station
dragging the whole net down.

"Darrel Toepfer" <(E-Mail Removed)> wrote in message
news:TzTnb.63483$(E-Mail Removed). ..
> "Enkidu" <(E-Mail Removed)> wrote...
> > "Graham in Melton" <(E-Mail Removed)> wrote...
> > > >
> > > > Sounds like they need a local, caching proxy server...
> > > >
> > > Or someone to redesign the website more like - Flash movies do not
> take
> > > 60k/s unless they are transmitting unnecessarily large files etc all
> the
> > > time.
> >
> > Copy the site to CDROM, and make a copy for each machine?
>
> "I have a wireless computer lab with 24 computers."
>
> Guess you missed that point? A local cache would allow the "wiress"
> network function as designed, given the limited pipe that they have
> feeding it...
>
>