running two wireless routers with one cable modem

Basically heres what trying to achieve.

Internet---->modem---->encrypted wireless network(ap1)----->open wireless network(ap2)
(acces point 1+2)

I've been successful up until the last part of it. Everything is fine up to (ap1) the problem starts when trying to get on the internet on (ap2). When you first open the internet browser you are able to access the internet but after a few moments you are unable to get on the internet anymore unless you power cycle (ap2) and then the whole process starts over again. I know it is probably just a setting that I'm missing but any help would be appreciated.

What I'm using

Cable co.--->motorola surfboard 5100 (provided by cable co.)---->linksys wrt54g--->
linksys wrt54g

do this.

internet--->router1--->AP1(on channel x with encryption)
internet--->router1--->AP2(on channel y without encryption)


or try putting the unecrypted one first and making sure they are on differnt channels and give them different SSIDS

Forgot to mention I've changed SSID's so they dont match. I also changed freqencies and the routers are 25' apart. they are also hardwired.

Thanks
J B

Ok make sure both have different SSIDs (which you have) put them on different channels, and dont broadcast the ssid on the encrypted one. what is probably going on is the computer is seeing both and wants to connect to both so it gets confused. make it so it cant see both or so that it can more easily tell the difference (before encryption even occurs) and it will be less confused. Putting them on different channels will probably help a bit but not broadcasting one of the SSIDs will help a lot Im thinking.

What if two internet connections isn't an option. Is what i'm trying to do possible?

From a security point of view.... Why would you have an untrusted-unencrypted Wireless Access Point on the "secure" side of the Encrypted WAP... It doesn't make sense and might work better of you go:-

Modem ---> Unencrypted ---> Encrypted

Also, change the channel of one of the WAPs to another frequecy.... It sounds like one is interfering witrh the other.

in my original illistration I was saying use one router then split to two APs instead of putting them in a chain, not two seperate connections. lol sorry I tryed ot make that clear.

ok i will try the unencryted on first and i have already tried different channels. it was one of the first things I did.
Thanks for the speedy help i'll try putting the unencrypted on firtst right now.
J B

and dont broadcast one of the SSIDs (if possible, easieset would not be broadcasting the encrypted since the people who want on already need one piece of info, getting them the second would be easier as opposed to having to give every user atleast one piece of info.)

oh, and set priority to the one you want in your wireless manager. also be sure you are only using one wireless manager.

no luck. i even tried leaving them both open but i got the same result. i could only get on the internet on the 2nd ap for a few moments then i could no longer access it. any other suggestion would be GREATLY appreciated
Thanks for the ideas so far
JB

ok, so I've still not gotten a clear picture. You have a surfboard 5100...single ethernet jack, right?

And you have 2 WRT54G devices. Where's this 'router' you mention? And is it really a switch? There is no reason this shouldn't work, if you set it up right.

Some questions:
1. How many IP's will your ISP allow you to have? Often it's only 1, but could be more.
2. How are you actually, *PHYSICALLY* connecting these devices. I don't care about channels, ssid's, wep/wpa/ROT13, I wanna know WHICH CABLE goes WHERE.
3. What is your final intent?

I am not trying to sound like a smart-ass nor am I claiming to be an expert on this matter but could it be because your PC is trying to connect to the AP it is receiving the highest signal strength and seeing how it is in the middle of two AP's it keeps bouncing back and forth between the two, one being encrypted and one being open?

I am attaching a "paper" titled "Routing and Channel Assignment in Multi-Channel Multi-Hop Wireless Networks with Single NIC Devices" by one Jungmin So and a Nitin H. Viada from the University of Illinois at Urbana-Champaign, that I found a few months back, I can't even remember what led me to find it, I think trying to find out if the signal comming out of an AP would constitute as a burst transmission or streaming, that I was surprised that I still had. It doesn't go into mixing open and encypted signals, and after about 5 pages I have no clue of what they are talking about, but maybe it could be of some use to you?

Cheers

As interesting as this all sounds noone seemed to ask if both AP's have the same IP or not.... You mentioned that they were both Linksys (192.168.1.1)... are they the wrt54g as in routers? or are they access points?

zencoder brings up a good point, if you dont have a router its not going to work but if you have

Code:

---

cable modem----unsecured wireless router-------secured wireless router
xx.xx.xx.xx        192.168.1.1                                192.168.1.2

---

that will work

or if you really want to stay even more security minded i would put the secured wireless router on a completely different subnet as the unsecured one. eg 172.xxx.xxx.1 or 10.x.x.1 etc

At this point it should (and does) work fine

Looking at all of the above...

Isn't it possible to set up just one router as a router? Make sure the second router is not doing anything *special* like maybe DHCP... let it just function as a switch / access point

That way I would also understand setting up the first router as "secure". The second would just be an "insecure" switch.

Also, is it possible to connect from AP2 to the internet using a cable in stead of wireless? Or does it then represent the same behaviour?

Just my two cents...

Quote:

---

Originally posted here by Spyrus
As interesting as this all sounds noone seemed to ask if both AP's have the same IP or not.... You mentioned that they were both Linksys (192.168.1.1)... are they the wrt54g as in routers? or are they access points?<snip>

---

Actually, this wouldn't matter IF you have both APs configured properly, since both are NAT'ing any of their clients, they can have identical networking schemes. Someone correct me if I'm wrong.

The WRT54G is Linksys' combo device...Router/Switch/Access Point. It does DHCP, NAT, and DNS (forwards requests) for it's clients. Therefore, both wireless signals would be considered separate network segments. What matters is how the two are physically AND logically connected to the cable modem. That has been the center of this question I posed awhile back. If you daisy-chain these two WRT54G's and run NAT with both (defualt behavior), you are in for nothing but headaches. NAT'ing traffic that is already NAT'ed might work, but I introduces many more points of failure and blinds to obscure what is really happening.

So what's the dealy-o? How have you wired these two devices to the cable modem?

sorry it been a while since my last response.
OK heres what i have

Internet ---(wired)---> modem ---(wired)---> wrt54g(ap1) ---(wired)--->wrt54g(ap2)

(I'm usuing (ap1) + (ap2) simply as a label for the 2 wrt54g's and not as a description to try and keep the confusion down)

The first wrt54g(ap1) is encrypted and is working fine both wirelessly and wired to the internet.
The second wrt54g(ap2)is wired from port 2 on (ap1) to the uplink port on (ap2).

Each wrt54g has 4 ports and an uplink port plus the wireless capability.

lets just forget about the wireless for a second and pretend that it doesn't exist.
because once i get the (ap2) working with a computer wired to it, the wireless will be easy.

Now with the two wrt54g's in the configuration mentioned at the top of this post when i try to get online (remember this is all getting put in place simply for internet access) i am able to get online for a few minutes then my access is gone. my computer says its connected, which it is, and there are no pop ups in the right hand corner of the screen saying anything has changed. The computer is still pulling a proper IP (assigned from ap2 which i set to be in 192.168.1.2xx range and ap1's IP are set to be in 192.168.1.1xx range).

Now linksys suggested i try disabling the DHCP on (ap2) but this had no change in the end
result. After that they told me this was beyond thier tech support. (Thank god for all the people here. People who actually care about networks)

I'll try and answer a few of your Q's now.

My ISP assigns one IP to either the computer or the first device connected to the modem.

They really could care less about how many computers are running through it.

My final intent with this is to have (ap1) used privately in the house by both residents. Then (ap2) will only be used when guest are over with their laptops. Kinda like a hot spot in a cafe.
Now i would just use one ap if i could be thier to set the guest computers up with the encryption but I won't and a lot of these people have trouble just finding the on button on thier computers.

As far as the laptop i'm using having trouble connecting because it's seeing both wireless connection and being confused. In the connection settings i set both connection points (ap1 + ap2) as manual so it won't connected unless i make it. the two ap's are about 25' apart so its not like they are to close and interefering with one another. Plus I set the channels to 1 and 11 respectively. there are no 2.4 ghz phones in the house.

You know what I'd do? I'd set up an 802.11a private network and an 802.11g public network. That way, your computers won't be confused since they work on two complete independently frequencies (you'd just need to make sure you have an 802.11a network card or a 802.11a/b/g combo card). Also, since few people actually use 802.11a outside of the workplace, you wouldn't really have to worry about people seeing it in the first place. I'd do the following:


Internet --> Modem --> Router -->
--> 802.11a WAP (encrypted, disable SSID broadcast, MAC filtering, etc.)
--> 802.11g WAP (open)

AJ

i understand that. the wireless isnt really the issue. the issue is getting (ap2) to actually allow me to get on the internet more than two minutes when i'm hard wired. the wirless part is the easy part. Once i figure out what's causing (ap2) to have this issue then I'll start on the wireless.

The wrt54g s three devices in one ita a wireless access point, a four port switch and a router.
so forget about the wireless for a second. if i took two of these strait out of the box and disabled the wireless i should be able to daisy chain them (wired) and have the second device allow me to access the internet which is plugged into the uplink port on the first device. unfortunetly i'm not having that result.

After a while i thought one of them was bad so i plugged each one directly into the modem (individually) and tested each port and they both worked.


Thanks guys
still frustraded, J B

Quote:

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Originally posted here by zencoder
Actually, this wouldn't matter IF you have both APs configured properly, since both are NAT'ing any of their clients, they can have identical networking schemes. Someone correct me if I'm wrong.

The WRT54G is Linksys' combo device...Router/Switch/Access Point. It does DHCP, NAT, and DNS (forwards requests) for it's clients. Therefore, both wireless signals would be considered separate network segments. What matters is how the two are physically AND logically connected to the cable modem. That has been the center of this question I posed awhile back. If you daisy-chain these two WRT54G's and run NAT with both (defualt behavior), you are in for nothing but headaches. NAT'ing traffic that is already NAT'ed might work, but I introduces many more points of failure and blinds to obscure what is really happening.

So what's the dealy-o? How have you wired these two devices to the cable modem?

---

What I was getting as was.... are both AP's the IP address 192.168.1.1... AFAIK you cant have both with the same IP address connected to the same network :rolleyes: . That is why i brought it up. One should have a different IP than the other so that they don't collide and not work(but he has clarified that they are seperate IPs). Now that I think about it would it make more sense to disable DHCP and NAT on AP2 so that they arent both trying to hand out addresses.

Or could he just put AP2 in the DMZ of AP1 and then let it handle its own NAT but still disable DHCP on AP2? Or is this even more confusing ;)

Edit:
When you had your PC connected to AP2, did you try to ping 192.168.1.1 (or whatever AP1's IP is?) did it work after you lost internet? what about when you try to ping 192.168.100.1 (this is your cable modem). Can you ping either one?
Also try putting AP2 in AP1's DMZ. I dont see how this could hurt anything other than port configurations should pass through AP1 easier.

How about posting the IP, subnet mask, and default gateway for the PC and both sides of each router? It looks like there would be problems getting traffic from a 192.168.1.2xx IP to a 192.168.1.1xx IP on another subnet if you used the typical 255.255.255.0 subnet mask. I'm not sure how that would cause it to work and then stop, though.

Also, unless you reverse them, I don't see the point in doing this. Traffic from your unsecured network will just be another node on your secured LAN. Aside from issues related to NAT, hosts on the unsecured network will have the same connectivity to the hosts on your secured network as if they were also directly on the secured network.

thanks for giving me some more options guys as soon as i can try them i'll post back


Thanks
J B

Quote:

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Originally posted here by josby
...traffic from a 192.168.1.2xx IP to a 192.168.1.1xx IP on another subnet if you used the typical 255.255.255.0 subnet mask...

---

Josby is on the right track. If you have one ap running 192.168.1.1 and the other running 192.168.1.2, and the subnet mask is 255.255.255.0, both aps are on the same network segment and will conflict with each other. To separate the network segments, you must run one ap on 192.168.1.x and the other on 192.168.2.x (or whatever your favorite private IP range is). Set the subnet mask to 255.255.255.0. This makes it possible to set a range of IPs on one ap DHCP to 192.168.1.1 - 255 and the other to 192.168.2.1 - 255. This places the two units on completely different network segments. Configure one secure and one open, however you want.

If you want your client system to use the secure net, set it up with the ap and security, then set that as the preferred.

Thanks everyone for all the help!
I got it taken care of because of you.

Rapier57 you hit it right on the nose. Once I changed the second ap's IP to 192.168.2.1 the problem disappeared. i'm actually typing this through the second ap.

this is what it looks like now

Internet---(wired)--->wrt54g(192.168.1.1)---(wired)--->wrt54g(192.168.2.1)

it works great!


Thanks everyone
JB

Cool...all those times I've had to learn subnet masking for certifications and classes have finally been useful for something...hehe

Just to be a smartass, you also could have changed your subnet masks to 255.255.255.128, giving you two subnets, 192.168.1.1-126 and 192.168.1.129-254 :)

Thanks guys, this solved a problem I was having with sharing my dialup connection through an old dell optiplex (internet gateway) and a microsoft router I had found on the side of the road somewhere. I had set the WAN subnet of the router and the wired NIC of the gateway as the same as the subnet on the other side of the router, and used NAT32 to route traffic from the router to the internet thru the gateway over dialup. It was giving me intermittent connection problems, and the traceroute wasn't detecting my gateway, but it'd detect everything else just fine. I couldn't connect to the gateway from inside the network nor from over the internet, but I COULD route packets thru for short periods of time.

I had completely forgotten about the conflicts of two DHCP-offering devices.

Changing the subnet on the gateway solved pretty much every problem I was having. Thanks again.