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windsurferLA
04-23-08, 02:23 PM
Multiple access points to flood an area.

My attempts to provide reliable wireless access to guest laptop
computers over an area spanning about 100 feet have proved unsuccessful.
I suspect the problem is interference from numerous other wireless
devices in the area. A possible solution would be to position two
separate wireless routers (access points) toward the edges of the area
with each wireless router (access points) hardwire linked to the modem
via (possibly an Ethernet switch and) CAT5 cable.

My current wireless router / access point of choice is the D-Link
DI-524. It has been chosen because the native IP range 192.168.0.X of
the D-Link does not overlap the 192.168.1.X IP address range of the
router built into the 2WIRE2701 modem (wireless option disabled). My
guess is that I can either: (1) configure each D-Link wireless router so
they have non-overlapping IP address ranges and feed them in parallel
from a switch, or (2) disable the DHCP in one of the units, and feed it
(the second in the chain) from the first unit.

Will either of these schemes work? How do I best configure the D-Link
DI-524 devices so they act in parallel to flood the area with signal?

WindsurferLA

Bill Kearney
04-23-08, 05:06 PM
> Multiple access points to flood an area.

Better describe "the area".

> I suspect the problem is interference from numerous other wireless devices
> in the area.

Possibly. But without describing where you're trying to do this it's
impossible to say. If you have any control over the other devices it might
be possible to reduce the amount of interference. But if they're not yours
and you can't contact who's running them then it may not be possible to do
what you're after. Rather it might be possible, but perhaps only with more
access points, each running at a lower power.

Likewise if the interferring systems don't need to be covering such a wide
area it may be advantageous for THEM to reduce their own radio power levels.

> A possible solution would be to position two separate wireless routers
> (access points) toward the edges of the area with each wireless router
> (access points) hardwire linked to the modem via (possibly an Ethernet
> switch and) CAT5 cable.

Without better info it's impossible to say if that's right or not. But yes,
in general, you put an access point where you want coverage and run wire
back to the switch.

> My current wireless router / access point of choice is the D-Link DI-524.
> It has been chosen because the native IP range 192.168.0.X of the D-Link
> does not overlap the 192.168.1.X IP address range of the router built into
> the 2WIRE2701 modem (wireless option disabled)

All devices of this sort have configurable options for their IP address
and/or IP range. Chosing one based on that is like chosing a green car
because you think it's faster than a blue one (everyone knows red is faster
anyway. Heh)

> My guess is that I can either: (1) configure each D-Link wireless router
> so they have non-overlapping IP address ranges and feed them in parallel
> from a switch, or (2) disable the DHCP in one of the units, and feed it
> (the second in the chain) from the first unit.

Use one as a router, use the other as an access point. They can be on the
same subnet, just make one of the run DHCP and disable it on the other.
DHCP requests will be passed through one to the other via the wired ethernet
connection. An access point is basically 'dumb' in that all it does is pass
traffic from the wired network to/from the wireless clients connecting to
it.

ps56k
04-23-08, 06:56 PM
windsurferLA wrote:
> Multiple access points to flood an area.
>
> My attempts to provide reliable wireless access to guest laptop
> computers over an area spanning about 100 feet have proved
> unsuccessful. I suspect the problem is interference from numerous
> other wireless devices in the area. A possible solution would be to
> position two separate wireless routers (access points) toward the
> edges of the area with each wireless router (access points) hardwire
> linked to the modem via (possibly an Ethernet switch and) CAT5 cable.
>
> My current wireless router / access point of choice is the D-Link
> DI-524. It has been chosen because the native IP range 192.168.0.X of
> the D-Link does not overlap the 192.168.1.X IP address range of the
> router built into the 2WIRE2701 modem (wireless option disabled). My
> guess is that I can either: (1) configure each D-Link wireless router
> so they have non-overlapping IP address ranges and feed them in
> parallel from a switch, or (2) disable the DHCP in one of the units,
> and feed it (the second in the chain) from the first unit.
>
> Will either of these schemes work? How do I best configure the D-Link
> DI-524 devices so they act in parallel to flood the area with signal?

as the other reply has indicated....
we really need more details.

You seem to mixing lots of different technical topics,
but at the same time, don't really have a handle on technology.
The entire paragraph on router "native IP range" tends to magnify that.

SO - what is the real situation, and the area you are trying to cover ?
Wait - 100ft ??? Are you kidding ? A single AP will do that - it's like 3
houses ?
I can see my AP from up and down the block in all directions,
along with several neighbors....

What is the Internet connection available to you ?
Is it just a simple DSL line via your 2WIRE2701 modem ?

Where will the AP's be located ?
How powered ?
and how connected back to your DSL modem or main router ?

windsurferLA
04-23-08, 11:03 PM
reply at bottom..

ps56k wrote:
> windsurferLA wrote:
>> Multiple access points to flood an area.
>>
>> My attempts to provide reliable wireless access to guest laptop
>> computers over an area spanning about 100 feet have proved
>> unsuccessful. I suspect the problem is interference from numerous
>> other wireless devices in the area. A possible solution would be to
>> position two separate wireless routers (access points) toward the
>> edges of the area with each wireless router (access points) hardwire
>> linked to the modem via (possibly an Ethernet switch and) CAT5 cable.
>>
>> My current wireless router / access point of choice is the D-Link
>> DI-524. It has been chosen because the native IP range 192.168.0.X of
>> the D-Link does not overlap the 192.168.1.X IP address range of the
>> router built into the 2WIRE2701 modem (wireless option disabled). My
>> guess is that I can either: (1) configure each D-Link wireless router
>> so they have non-overlapping IP address ranges and feed them in
>> parallel from a switch, or (2) disable the DHCP in one of the units,
>> and feed it (the second in the chain) from the first unit.
>>
>> Will either of these schemes work? How do I best configure the D-Link
>> DI-524 devices so they act in parallel to flood the area with signal?
>
> as the other reply has indicated....
> we really need more details.
>
> You seem to mixing lots of different technical topics,
> but at the same time, don't really have a handle on technology.
> The entire paragraph on router "native IP range" tends to magnify that.
>
> SO - what is the real situation, and the area you are trying to cover ?
> Wait - 100ft ??? Are you kidding ? A single AP will do that - it's like 3
> houses ?
> I can see my AP from up and down the block in all directions,
> along with several neighbors....
>
> What is the Internet connection available to you ?
> Is it just a simple DSL line via your 2WIRE2701 modem ?
>
> Where will the AP's be located ?
> How powered ?
> and how connected back to your DSL modem or main router ?
>
>
>

Thanks for prompt reply... It looks like I've found some real experts.

The area I'm trying to cover is the top floor of an apartment house
occupied by ten friends and potentially ten lap top computers. The
building is 100 feet from front to back and 30 feet wide. The building
is in an area with lots and lots of students, many of who have their own
wireless access points. A check of networks in range will usually turn
up at least ten networks and often many more. I really don't know who
those other user are let alone being able to coordinate channel
selection and power settings with them.

The users on the top floor have a variety of laptop computers, none of
which are set up to use MIMO or any of the proprietary range extension
techniques. Currently, there is one wireless router located in the
center of the top floor; it is set for maximum power on the least used
channel. Although the current router and others that we have tried claim
to deliver range to 100 feet, reception beyond 30 feet is marginal (one
bar) to useless, especially at night when many others seem to power up
their computers and wireless equipment. A directional antenna
advertised as providing 10 db of gain did not seem to help significantly
independent of its positioning. (It was a pole antenna that supposedly
achieved its gain by flattening the radiation pattern.) It seems to be
possible to get reception through two walls, but any more that that and
reception is unacceptable. Each user wants to be able to connect from
his/her desk and not relocate to the kitchen counter because of its
closer position to the central source.

I'm aware that the you can change the IP address ranges on most all
routers, but having units whose default states don't conflict makes
network repair easier; it is one less thing to have to reset when
something goes wrong.

The Internet feed is a simple DSL line via the 2WIRE2701 modem. The
thought is to disable the wireless capability of the 2WIRE2701 (there is
a control panel option for switching it off) and connect one of the four
RJ45 Ethernet ports on the 2WIRE2701 to each of the two D-Link DI-524
wireless access points via a physical CAT5 Ethernet cable. Each D-Link
DI-524 would be powered form a local source. Each would be located near
the opposite ends of the building.

I'm plan again to try the tandem configuration recommended by Bill
Kearney in his post wherein the DHCP is disabled on the second-in-line
router.

windsurferLA
04-23-08, 11:06 PM
Bill ... Thanks for prompt reply.

Your suggestion makes sense.

I'm going to give your tandum feed configuration a try. It is going to
be a few days before my second DI-524 arrives and I have the opportunity
to lash it up.

see reply to ps56k's posting for my more detailed explanation.

WindsurferLA.

Bill Kearney wrote:
>> Multiple access points to flood an area.
>
> Better describe "the area".
>
>> I suspect the problem is interference from numerous other wireless
>> devices in the area.
>
> Possibly. But without describing where you're trying to do this it's
> impossible to say. If you have any control over the other devices it
> might be possible to reduce the amount of interference. But if they're
> not yours and you can't contact who's running them then it may not be
> possible to do what you're after. Rather it might be possible, but
> perhaps only with more access points, each running at a lower power.
>
> Likewise if the interferring systems don't need to be covering such a
> wide area it may be advantageous for THEM to reduce their own radio
> power levels.
>
>> A possible solution would be to position two separate wireless routers
>> (access points) toward the edges of the area with each wireless router
>> (access points) hardwire linked to the modem via (possibly an Ethernet
>> switch and) CAT5 cable.
>
> Without better info it's impossible to say if that's right or not. But
> yes, in general, you put an access point where you want coverage and run
> wire back to the switch.
>
>> My current wireless router / access point of choice is the D-Link
>> DI-524. It has been chosen because the native IP range 192.168.0.X of
>> the D-Link does not overlap the 192.168.1.X IP address range of the
>> router built into the 2WIRE2701 modem (wireless option disabled)
>
> All devices of this sort have configurable options for their IP address
> and/or IP range. Chosing one based on that is like chosing a green car
> because you think it's faster than a blue one (everyone knows red is
> faster anyway. Heh)
>
>> My guess is that I can either: (1) configure each D-Link wireless
>> router so they have non-overlapping IP address ranges and feed them in
>> parallel from a switch, or (2) disable the DHCP in one of the units,
>> and feed it (the second in the chain) from the first unit.
>
> Use one as a router, use the other as an access point. They can be on
> the same subnet, just make one of the run DHCP and disable it on the
> other. DHCP requests will be passed through one to the other via the
> wired ethernet connection. An access point is basically 'dumb' in that
> all it does is pass traffic from the wired network to/from the wireless
> clients connecting to it.
>
>

Bill Kearney
04-24-08, 06:32 AM
> Thanks for prompt reply... It looks like I've found some real experts.
>
> The area I'm trying to cover is the top floor of an apartment house
> occupied by ten friends and potentially ten lap top computers. The
> building is 100 feet from front to back and 30 feet wide.

> The building is in an area with lots and lots of students, many of who
> have their own wireless access points.

You're screwed. Trying to curb the amount of interference from all the
poorly configured routers will be like herding cats.

Unlicensed wireless can lead to just what you've encountered, a conflicting
mess.

> Currently, there is one wireless router located in the center of the top
> floor; it is set for maximum power on the least used channel.

For that small an area max power is probably not needed, nor desired.

Although the current router and others that we have tried claim
> to deliver range to 100 feet, reception beyond 30 feet is marginal (one
> bar) to useless, especially at night when many others seem to power up
> their computers and wireless equipment. A directional antenna advertised
> as providing 10 db of gain did not seem to help significantly independent
> of its positioning. (It was a pole antenna that supposedly achieved its
> gain by flattening the radiation pattern.) It seems to be possible to get
> reception through two walls, but any more that that and reception is
> unacceptable. Each user wants to be able to connect from his/her desk and
> not relocate to the kitchen counter because of its closer position to the
> central source.

Some construction materials will block enough of the signal to prevent
decent reception. Older buildings usually, but new buildings with metal
stud walls can also be problematic. The only solution, really, is to use
more access points at lower power.

> I'm aware that the you can change the IP address ranges on most all
> routers, but having units whose default states don't conflict makes
> network repair easier; it is one less thing to have to reset when
> something goes wrong.

Again, you're making a choice based on a less-than-smart plan. If you want
reset programmability then get a router that can have a 3rd party firmware
loaded. Configure that firmware ahead of time to your desired setup (by
recompiling the firmware) and load that on each. Frankly, that's a lot more
trouble than it's worth. Once you have this setup properly there really
should be no need to reset the devices to factory settings.

> The Internet feed is a simple DSL line via the 2WIRE2701 modem. The
> thought is to disable the wireless capability of the 2WIRE2701 (there is a
> control panel option for switching it off) and connect one of the four
> RJ45 Ethernet ports on the 2WIRE2701 to each of the two D-Link DI-524
> wireless access points via a physical CAT5 Ethernet cable. Each D-Link
> DI-524 would be powered form a local source. Each would be located near
> the opposite ends of the building.

Probably not opposite but more like the lobes of a barbell. As in:

|-------------(*)-----------------------------(*)-----------------|

> I'm plan again to try the tandem configuration recommended by Bill Kearney
> in his post wherein the DHCP is disabled on the second-in-line router.

No, leave it enabled in the central router, the 2wire unit. Disable it in
the others, configure them as just dumb access points. This way you'll only
have to deal with DHCP and other settings on the one router. You could use
one or the other of the Dlink units but it's six of one, half-dozen of
another. If you use the 2wire you'd be able to reboot the wireless units
independently without losing connectivity on the other. Likewise if you
temporarily need to add more wifi routers it'll be trivial to set them up as
an access point and nothing else.

But you're still going to be faced with the interference problems. This may
not be solvable without cooperation from the other device owners.

-Bill Kearney

seaweedsl
04-24-08, 10:42 AM
I''m thinking the same as Bill's suggestion; assuming that you are
using omni antennas (makes sense here), set up your routers not at the
very ends but in the barbell shape, maybe with a third in the middle.

Considering that you are trying to cover a long area, you may want to
go ahead and keep the 2-wire radio operating as well.

Placement is going to be everything. Luckily, your area is only 30 ft
wide, so it will be a line, not a grid. Try to set up so there is
always an AP within 2 walls of any user.

Here's a suggestion:
Make a map of the walls and the needed coverage to play around with
locations for the APs.
Place one AP two walls in from the end of your desired coverage. Go
four walls over and place the middle router. Go four walls further
and place the end router. Hopefully you have now covered the whole
thing. Make sure that your middle router is on a different channel
than your end ones at least.

Who knows if it will ever work with all the other APs that seem to be
present. I would do a site survey first to see what the channel
mapping currently is. You might be able to prevail upon one or two
key AP owners to switch channels so that everything works better.
Failing any of that, doing it blindly, I would assume that most are
set to channel 6 and that using 1 and 11 for your APs will help.

windsurferLA
04-28-08, 12:01 AM
Bill & "seeweeds" - thanks again for suggestions...

I'm aware that getting around interference from 20 (by actual count
although they may not all be present at the same time) within range
networks presents a challenge. I planned to use the dumbbell placement
scheme suggested by "seeweeds," as well as leaving the 2WIRE operating
in the middle as well. I currently don't see why lowering the power
settings on my access points will improve my signals; I can see it
making for less problems for the others.

Does this procedure appear correct?

I'll reset the IP address of each DI-524 units from 192.168.0.1
(default) to perhaps 192.168.0.2 and 192.168.0.3, so I can access the
control panel of each independently. The DHCP feature in each D-Link
router will be turned off. Two CAT5 cables will be run from RJ45 LAN
jacks on the 2WIRE to one of the four RJ45 LAN jacks on each of the
D-Link (no longer router) access points. I am assuming that the 2WIRE
DHCP will assign non-conflicting IP addresses each of the D-Link routers
and all DI-524 wireless clients without manual intervention.

WindsurferLA


Bill Kearney wrote:
>> Thanks for prompt reply... It looks like I've found some real experts.
>>
>> The area I'm trying to cover is the top floor of an apartment house
>> occupied by ten friends and potentially ten lap top computers. The
>> building is 100 feet from front to back and 30 feet wide.
>
>> The building is in an area with lots and lots of students, many of who
>> have their own wireless access points.
>
> You're screwed. Trying to curb the amount of interference from all the
> poorly configured routers will be like herding cats.
>
> Unlicensed wireless can lead to just what you've encountered, a
> conflicting mess.
>
>> Currently, there is one wireless router located in the center of the
>> top floor; it is set for maximum power on the least used channel.
>
> For that small an area max power is probably not needed, nor desired.
>
> Although the current router and others that we have tried claim
>> to deliver range to 100 feet, reception beyond 30 feet is marginal
>> (one bar) to useless, especially at night when many others seem to
>> power up their computers and wireless equipment. A directional
>> antenna advertised as providing 10 db of gain did not seem to help
>> significantly independent of its positioning. (It was a pole antenna
>> that supposedly achieved its gain by flattening the radiation
>> pattern.) It seems to be possible to get reception through two walls,
>> but any more that that and reception is unacceptable. Each user wants
>> to be able to connect from his/her desk and not relocate to the
>> kitchen counter because of its closer position to the central source.
>
> Some construction materials will block enough of the signal to prevent
> decent reception. Older buildings usually, but new buildings with metal
> stud walls can also be problematic. The only solution, really, is to
> use more access points at lower power.
>
>> I'm aware that the you can change the IP address ranges on most all
>> routers, but having units whose default states don't conflict makes
>> network repair easier; it is one less thing to have to reset when
>> something goes wrong.
>
> Again, you're making a choice based on a less-than-smart plan. If you
> want reset programmability then get a router that can have a 3rd party
> firmware loaded. Configure that firmware ahead of time to your desired
> setup (by recompiling the firmware) and load that on each. Frankly,
> that's a lot more trouble than it's worth. Once you have this setup
> properly there really should be no need to reset the devices to factory
> settings.
>
>> The Internet feed is a simple DSL line via the 2WIRE2701 modem. The
>> thought is to disable the wireless capability of the 2WIRE2701 (there
>> is a control panel option for switching it off) and connect one of the
>> four RJ45 Ethernet ports on the 2WIRE2701 to each of the two D-Link
>> DI-524 wireless access points via a physical CAT5 Ethernet cable.
>> Each D-Link DI-524 would be powered form a local source. Each would be
>> located near the opposite ends of the building.
>
> Probably not opposite but more like the lobes of a barbell. As in:
>
> |-------------(*)-----------------------------(*)-----------------|
>
>> I'm plan again to try the tandem configuration recommended by Bill
>> Kearney in his post wherein the DHCP is disabled on the second-in-line
>> router.
>
> No, leave it enabled in the central router, the 2wire unit. Disable it
> in the others, configure them as just dumb access points. This way
> you'll only have to deal with DHCP and other settings on the one
> router. You could use one or the other of the Dlink units but it's six
> of one, half-dozen of another. If you use the 2wire you'd be able to
> reboot the wireless units independently without losing connectivity on
> the other. Likewise if you temporarily need to add more wifi routers
> it'll be trivial to set them up as an access point and nothing else.
>
> But you're still going to be faced with the interference problems. This
> may not be solvable without cooperation from the other device owners.
>
> -Bill Kearney

Bill Kearney
04-28-08, 09:13 PM
> I currently don't see why lowering the power settings on my access points
> will improve my signals; I can see it making for less problems for the
> others.

If your unit isn't seeing the others, due to lower power and antenna aiming
then it won't have to retry. Unfortunately the cards in the laptops will
probably not be as configurable.

> I'll reset the IP address of each DI-524 units from 192.168.0.1 (default)
> to perhaps 192.168.0.2 and 192.168.0.3, so I can access the control panel
> of each independently. The DHCP feature in each D-Link router will be
> turned off. Two CAT5 cables will be run from RJ45 LAN jacks on the 2WIRE
> to one of the four RJ45 LAN jacks on each of the D-Link (no longer router)
> access points. I am assuming that the 2WIRE DHCP will assign
> non-conflicting IP addresses each of the D-Link routers and all DI-524
> wireless clients without manual intervention.

Sounds like a plan. You may want to configure the D-link units with static
addresses; ones not in the DHCP range. That way they'll always be
accessible at known addresses, not at the mercy of DHCP leases, which will
change eventually.

And whosuggested the barbell layout? Hmmm?

seaweedsl
04-29-08, 02:42 PM
On Apr 28, 12:01 am, windsurferLA <ps144...@yahoo.com> wrote:

> I'll reset the IP address of each DI-524 units from 192.168.0.1
> (default) to perhaps 192.168.0.2 and 192.168.0.3, so I can access the
> control panel of each independently.

Yep.

>The DHCP feature in each D-Link
> router will be turned off.

Yep.

>Two CAT5 cables will be run from RJ45 LAN
> jacks on the 2WIRE to one of the four RJ45 LAN jacks on each of the
> D-Link (no longer router) access points.

Yes.

>I am assuming that the 2WIRE
> DHCP will assign non-conflicting IP addresses each of the D-Link routers
> and all DI-524 wireless clients without manual intervention.
>

Nope, you already assigned non-conflicting addresses to the two D-
links yourself. They are now fixed. What the 2wire's DHCP will do
is assign IP addresses to the clients of the D-links, rather than the
D-links trying to do it themselves. That way everybody is on the same
subnet with a unique address.

Again, channel assignment may make a big difference. Don't forget
about that. Do a Netstumbler survey to map the existing APs and
where they are stronger to help you sort that out.

Also, if BILL's barbell (with 2Wire added) scheme doesn't work, then
there are other possible approaches to try. But that seems like the
best

Steve

windsurferLA
05-01-08, 12:15 AM
Thanks again for the suggestions. I was unaware of Netstumbler as
similar tools.

I been successful at getting the first of the two peripheral wireless
routers working as access points in a close in lash up, so it looks like
I've got the IP issues under control. Now I just need to finish
stringing CAT5 cables.

Thanks again...
WindsurferLA


seaweedsl wrote:
> On Apr 28, 12:01 am, windsurferLA <ps144...@yahoo.com> wrote:
>
>> I'll reset the IP address of each DI-524 units from 192.168.0.1
>> (default) to perhaps 192.168.0.2 and 192.168.0.3, so I can access the
>> control panel of each independently.
>
> Yep.
>
>> The DHCP feature in each D-Link
>> router will be turned off.
>
> Yep.
>
>> Two CAT5 cables will be run from RJ45 LAN
>> jacks on the 2WIRE to one of the four RJ45 LAN jacks on each of the
>> D-Link (no longer router) access points.
>
> Yes.
>
>> I am assuming that the 2WIRE
>> DHCP will assign non-conflicting IP addresses each of the D-Link routers
>> and all DI-524 wireless clients without manual intervention.
>>
>
> Nope, you already assigned non-conflicting addresses to the two D-
> links yourself. They are now fixed. What the 2wire's DHCP will do
> is assign IP addresses to the clients of the D-links, rather than the
> D-links trying to do it themselves. That way everybody is on the same
> subnet with a unique address.
>
> Again, channel assignment may make a big difference. Don't forget
> about that. Do a Netstumbler survey to map the existing APs and
> where they are stronger to help you sort that out.
>
> Also, if BILL's barbell (with 2Wire added) scheme doesn't work, then
> there are other possible approaches to try. But that seems like the
> best
>
> Steve
>
>