# Home network situation/questions



## lifeislife (Jul 23, 2004)

I have an interesting home networking/routing situation and wanted to see if someone has an idea what may be going on. 

Recently I implemented the following in my home network:

Telephone line -> DSL modem -> Wired-only router
Wired router's ethernet port1 -> Wireless router's ethernet port1
Wireless router's ethernet port2 -> loopback to "internet" port on the same wireless router

IP address of the DSL modem: 192.168.0.1
IP address of wired router: 192.168.1.1 and DHCP on, starting from 192.168.1.2 for 25 addresses
IP address of wireless router: 192.168.15.1 and DHCP on, starting from 192.168.15.2 for 25 addresses
Also, dynamic routing for wireless router is on, going to 192.168.1.1 with 1 hop. 

Both the routers are WRTP54G from linksys (vonage devices). On the first one I have simply disabled the wireless functionality so that I don't end up having two wireless networks in the house. 

So the problems:

1. First of all, I wanted to put 192.168.1.99 as the IP address of the wireless router. But for some reason I cannot do it. Every time I try to do it it resets back to 192.168.15.1. 
2. 192.168.15.1 would not be too bad but sometimes wireless computers get a 192.168.15.x address and are unable to browse the internet, and worse, I cannot connect to the router configuration pages at 192.168.15.1 or 192.168.1.1. The only way to get out of this jam is to connect the computer with a cable to the wireless router and let it get connected hard-wired. 

Anyone have any suggestions on how I can iron this these kinks in the network? 

BTW, when a hard-wired computer connects even to the wireless router, it gets IP address of 192.168.1.x.


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## deltafowler (Aug 28, 2007)

My head hurts.
Why the heck are you apparently daisy-chaining routers?

Can you do a graphical representation of this layout?


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## deltafowler (Aug 28, 2007)

Is the modem a strictly modem device or does it have routing and DHCP server functionality?
On the hardwired computer with the "wrong" IP, what is the gateway address?


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## lifeislife (Jul 23, 2004)

deltafowler said:


> My head hurts.
> Why the heck are you apparently daisy-chaining routers?
> 
> Can you do a graphical representation of this layout?


Sorry about that, I don't blame you. I tried drawing up the diagram on Visio but could not depict the key information in a way that can be saved and attached nicely. :-(

I am daisy-chaining because I want to be able to use the pre-wiring in my home, but since the control panel is deep inside the closet and since my "main" router also serves up Vonage telephone service, I need to keep the "main" router out in some room. If I keep the one Vonage router in the control panel I risk lowering the signal strength of the wireless signal, and of course my telephone service.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Is the modem a strictly modem device or does it have routing and DHCP server functionality?
> On the hardwired computer with the "wrong" IP, what is the gateway address?


The DSL modem is a Speedstream 4100. I think it does DHCP because the router that connects to it obtains a WAN IP from the DSL modem. Not sure about its routing functionality.

The hard-wired computer seems to have the "right" IP in that I have never had a hard-wired computer not be able to go to the internet. Its the wireless that seems to be getting 192.168.15.x addresses and therefore being unable to go to the internet or anywhere else.


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## deltafowler (Aug 28, 2007)

Is this correct?










If it is, remove the loopback and turn off DHCP on the second (wireless router).
Turn off dynamic routing.
Increase the DHCP pool on router 1 by whatever amount is needed to allocate all devices connected both wirelessly and cabled.

Essentially, you only need to use the second router as a wireless AP and switch. You need neither DHCP or Routing from that device. It's passive.
The Internet port should not be used at all.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Is this correct?
> 
> 
> 
> ...


Wow, deltafowler. That was quick, and 100% accurate! Thanks for doing it, and yes, that is absolutely correct depiction.

I had the setup as you described earlier, but Vonage would need something to come in to the internet port otherwise it would not provide the phone signal. Even though the router is able to "go to the internet", it does not have "incoming internet" and as a result, there is no phone connection. :-(


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## deltafowler (Aug 28, 2007)

Here's how it should look.
In order to configure the second router, manually assign it an IP of 192.168.1.199. I added that after the drawing, but that will allow you to log into it via wired or wireless from either router's clients.


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## deltafowler (Aug 28, 2007)

With it this way, would Vonage not still be hitting the Internet port on the first router, albeit by way of the "switch"?

Sorry, never had my hands on Vonage stuff.

Perhaps someone else can add to it from here.

At least I got my head to stop hurting


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Here's how it should look.
> In order to configure the second router, manually assign it an IP of 192.168.1.199. I added that after the drawing, but that will allow you to log into it via wired or wireless from either router's clients.


I guess what I should have mentioned is there is a telephone connection missing from the diagram. I have updated the original diagram by a little bit. Attached here.


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## harsh (Jun 15, 2003)

You can't have two routers sharing the same IP address space. Routers are a one address to many type device (NAT).

What you need is one router with wireless enabled and a switch. Alternatively, you might find firmware that will convert your perfectly good wireless router into a dumb wireless bridge.

If your DSL modem is in the wrong room, move it.


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## lifeislife (Jul 23, 2004)

harsh said:


> You can't have two routers sharing the same IP address space. Routers are a one address to many type device (NAT).
> 
> What you need is one router with wireless enabled and a switch. Alternatively, you might find firmware that will convert your perfectly good wireless router into a dumb wireless bridge.
> 
> If your DSL modem is in the wrong room, move it.


What if I change the subnet of the first router (192.168.1.1) to 255.255.255.128 and then give the second router an IP of 192.168.1.99?

I would like to use the pre-wiring in my home and so I am trying to put the DSL modem in the control panel box. Don't think I have any other idea of how to "share" the internet connection to for example the directv box which is in the living room. I know there are bridges and everything, but if you have multiple jacks which can get internet connections, why not use those rather than buy a new device? Right ... ?


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## AlbertZeroK (Jan 28, 2006)

harsh said:


> You can't have two routers sharing the same IP address space. Routers are a one address to many type device (NAT).
> 
> What you need is one router with wireless enabled and a switch. Alternatively, you might find firmware that will convert your perfectly good wireless router into a dumb wireless bridge.
> 
> If your DSL modem is in the wrong room, move it.


actually, lifeislife's diagram with turning the DHCP off and changing the IP of the unit will effectively turn his wireless router into an access point. I've been doing it for years this way. Works fine, lasts long time!

You are wrong about not having two routers in the same IP subnet, you can. you just can't have both of them with DHCP on. This is a great method used to bridge two different networks. Been there done that too.

There are all sorts of cool networking tricks I've used including seting up multiple routers to a single lan for multiple public ip access to the network (just watch your gateways.) But lifeislife's most recent diagram will definately work!


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## lifeislife (Jul 23, 2004)

AlbertZeroK said:


> actually, lifeislife's diagram with turning the DHCP off and changing the IP of the unit will effectively turn his wireless router into an access point. I've been doing it for years this way. Works fine, lasts long time!
> 
> You are wrong about not having two routers in the same IP subnet, you can. you just can't have both of them with DHCP on. This is a great method used to bridge two different networks. Been there done that too.
> 
> There are all sorts of cool networking tricks I've used including seting up multiple routers to a single lan for multiple public ip access to the network (just watch your gateways.) But lifeislife's most recent diagram will definately work!


Wait, which diagram?  There were 2 posted by deltafowler and 1 by me. The one I posted was simply a clarification of deltafowler's diagram with the telephone (Vonage) connection updated.

So given that the Vonage service will not provide a telephone signal without something available in the internet port of the Wireless router, I cannot directly follow deltafowler's suggestion.

Now, if I understand correctly you are saying I may be able to do what I want with the connectivity I have, except that I should turn off DHCP and giving the router 192.168.1.99 or some such address. Right?

But won't turning off DHCP imply the wireless part of the router will not be able to assign IP's to wirelessly connected devices/computers?


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## deltafowler (Aug 28, 2007)

I did assume the phone(s) were plugged into to the green ports at one router or another.

Since you say you've previously tried that topology, but the phones didn't work, I further assume that the phone ports somehow function differently from the switch ports on the router.

Again, I've never seen or touched any Vonnage equipment, so I know nothing about them. Obviously, their phone ports somehow are tied back the WAN side of the router in order to function, rather than on the LAN side?


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## lifeislife (Jul 23, 2004)

deltafowler said:


> I did assume the phone(s) were plugged into to the green ports at one router or another.
> 
> Since you say you've previously tried that topology, but the phones didn't work, I further assume that the phone ports somehow function differently from the switch ports on the router.
> 
> Again, I've never seen or touched any Vonnage equipment, so I know nothing about them. Obviously, their phone ports somehow are tied back the WAN side of the router in order to function, rather than on the LAN side?


Yes, I think the Vonage phone ports expect the WAN port to be active, rather than simply trying to connect to the internet from the router. As a result, everything works perfectly except for my phone :-(


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## deltafowler (Aug 28, 2007)

Have you tried connecting Ehternet port on Router 1 to the Internet port on router 2, and then running the setup wizard that way?

Seems to me that the wizard will pickup the presence of Internet signal just as it would if it were coming from the modem as on router 1, and setup accordingly.

You may have manually assign an IP on router 2, since it will probably try to setup using 192.168.15.1 (default).

Sorry... I keep editing....

Try this?


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## harsh (Jun 15, 2003)

lifeislife said:


> What if I change the subnet of the first router (192.168.1.1) to 255.255.255.128 and then give the second router an IP of 192.168.1.99?


The whole point of subnets is to keep different IP ranges on the same basic IP series separate. If you want everything talking, you need to have exactly one DHCP server.

You simply don't need a second router and trying to convert it to a switch or a bridge is a waste. You can sell or donate the extra router and buy a small switch for under $25.


> Don't think I have any other idea of how to "share" the internet connection to for example the directv box which is in the living room.


We call these devices switches. They extend the number of devices that can connect to each other and to a single Internet gateway. In my network, only the SIP and any wireless traffic goes directly to the router. Everything else is connected to two gigabit switches that connect all the computers and NAS devices.

If I get a different kind of Internet connection, I can keep or change the router without tearing up my computer LAN.

You can do what you are trying to do, but it requires a lot of hair pulling and experimenting with firmware and router configurations.


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## bsmith (Sep 29, 2007)

lifeislife said:


> Sorry about that, I don't blame you. I tried drawing up the diagram on Visio but could not depict the key information in a way that can be saved and attached nicely. :-(
> 
> I am daisy-chaining because I want to be able to use the pre-wiring in my home, but since the control panel is deep inside the closet and since my "main" router also serves up Vonage telephone service, I need to keep the "main" router out in some room. If I keep the one Vonage router in the control panel I risk lowering the signal strength of the wireless signal, and of course my telephone service.


Here's an idea why not just plug the phone into the phone one port of the first router. You say you have a prewired house. If it's structured cable no sweat, make some patch cables and be done with it. Go to Home Depot or Lowes or wherever and buy a cheap RJ45 crimp tool and ends. cut off one RJ11 end of a standard phone patch cable and put a 45 on there. using pins 4&5 (the blue pair on a regular network cable). I honestly think you're making this more complicated than it needs to be. Ethernet cable runs are set at a theoretical max of 100m, generally speaking an analog device is good to 1000 feet. 
Also if you plug one port of the switch into the WAN port you are creating a switch loop that can cause all kinds of weird things to happen.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Have you tried connecting Ehternet port on Router 1 to the Internet port on router 2, and then running the setup wizard that way?
> 
> Seems to me that the wizard will pickup the presence of Internet signal just as it would if it were coming from the modem as on router 1, and setup accordingly.
> 
> ...


In this setup, do I set the second router's DHCP serving on? How about dynamic routing?


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## lifeislife (Jul 23, 2004)

harsh said:


> The whole point of subnets is to keep different IP ranges on the same basic IP series separate. If you want everything talking, you need to have exactly one DHCP server.
> 
> You simply don't need a second router and trying to convert it to a switch or a bridge is a waste. You can sell or donate the extra router and buy a small switch for under $25.We call these devices switches. They extend the number of devices that can connect to each other and to a single Internet gateway. In my network, only the SIP and any wireless traffic goes directly to the router. Everything else is connected to two gigabit switches that connect all the computers and NAS devices.
> 
> ...


So let's see, I have two separate situations - being able to get "internet" access from the wall jacks, and being able to get wireless/vonage access reliably.

If I put a switch in the control panel, I may get internet access in all the wall jacks, but will all those jacks have public IP addresses? Not a good idea, right?

Also, if I put a switch "outside" then the wireless range goes down and the phone device will need to be near the panel inside the closet (near the Vonage device). Right?

Both situations, if true, are not optimal.


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## lifeislife (Jul 23, 2004)

bsmith said:


> Here's an idea why not just plug the phone into the phone one port of the first router. You say you have a prewired house. If it's structured cable no sweat, make some patch cables and be done with it. Go to Home Depot or Lowes or wherever and buy a cheap RJ45 crimp tool and ends. cut off one RJ11 end of a standard phone patch cable and put a 45 on there. using pins 4&5 (the blue pair on a regular network cable). I honestly think you're making this more complicated than it needs to be. Ethernet cable runs are set at a theoretical max of 100m, generally speaking an analog device is good to 1000 feet.
> Also if you plug one port of the switch into the WAN port you are creating a switch loop that can cause all kinds of weird things to happen.


There are two problems with the ideas - the first router is not activated for Vonage service and even to try the idea, I will have to deactivate my current ("second") router and activate the old one. Secondly, I can experiment with plugging and replugging and configuring and reconfiguring, but I am not bold enough or knowledgeable enough to start crimping RJ11's and RJ45's  That's a drastic step for me, which I would like to avoid.


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## deltafowler (Aug 28, 2007)

If you mean public addresses in the sense that they are visible from the net, then the answer is no.
That addressing stops at the WAN side of the modem, which uses NAT (Network Address Translation) to mask your home network from us.
http://www.whatsmyip.org/ will show you what your public address is.

Anything on your side of the modem is 192.x.x.x


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## deltafowler (Aug 28, 2007)

I did read that these routers give the phone ports a higher priority when IP traffic is high on the network.
So you should try to continue to use the ports as designed.

Any Vonage forums out there.
It may be best to take post there.
You're welcomed to use the drawings. I'll leave them in the Photobucket account indefinitely.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> If you mean public addresses in the sense that they are visible from the net, then the answer is no.
> That addressing stops at the WAN side of the modem, which uses NAT (Network Address Translation) to mask your home network from us.
> http://www.whatsmyip.org/ will show you what your public address is.
> 
> Anything on your side of the modem is 192.x.x.x


So if I put a 4-port switch instead of router #1, the 4 rooms will end up getting a 192.168.x.x type of address? I thought the DSL modem will simply provide the WAN IP to the device connected to it.


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## bsmith (Sep 29, 2007)

lifeislife said:


> So if I put a 4-port switch instead of router #1, the 4 rooms will end up getting a 192.168.x.x type of address? I thought the DSL modem will simply provide the WAN IP to the device connected to it.


Not anymore. In the old days it would, consumer stuff now days is trying to be all things to everyone. besides you said that your "router" gets it's IP from the modem. which tells me that it will do DHCP on the inside. I'd like to apologize if I get too technical I do this stuff for a living so I tend to blow by the explanations.


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## deltafowler (Aug 28, 2007)

That modem is capable of using DHCP and routing functions, yes.
You may want to check your ISP to see if it is setup that way for your installation.

A QUICK way to verify would be to turn off the router functions on the first router and plug the modem in Ethernet 1 and a PC in Ethernet 2.
If the PC gets an address in the 192.168.0.x octect, then it's issuing addresses for sure.

You could also log into the modem's configuration page and check it there as well.
I believe the defaults are 
username - blank
password - admin

As bsmith said, most of the newer stuff is doing it all these days.
I'm still bewildered as to why they don't install more than one Ethernet port on them, but I guess they're keeping costs down.

Embarq uses one called the 2-wire around here.
It has wireless and 4 Ethernet ports on the DSL modem/router.


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## lifeislife (Jul 23, 2004)

bsmith said:


> Not anymore. In the old days it would, consumer stuff now days is trying to be all things to everyone. besides you said that your "router" gets it's IP from the modem. which tells me that it will do DHCP on the inside. I'd like to apologize if I get too technical I do this stuff for a living so I tend to blow by the explanations.


So per deltafowler's instruction I checked the DSL modem configuration. There is a setting which is: "A very limited number of applications require that the public IP address assigned to the modem be used by the local LAN device.
Let LAN device share Internet address?" Currently this setting is "Yes, use public IP".

Should I switch it to NO and connect a switch and it should end up working as I planned?

btw, a VERY BIG thanks to all for being patient with this and helping me. Its absolutely fantastic of you. Appreciate it.


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## deltafowler (Aug 28, 2007)

Again, Vonage is something with which I have zero experience.
I'm guessing that Vonage is using the public IP and thus it must be setup this way.

The question then becomes whether this is turned on just for Vonage or is it on globally?

Run the Symantec security test and see what it tells you.
http://security.symantec.com/


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Again, Vonage is something with which I have zero experience.
> I'm guessing that Vonage is using the public IP and thus it must be setup this way.
> 
> The question then becomes whether this is turned on just for Vonage or is it on globally?
> ...


Ok, so I unplugged router #1 and inserted a 4-port hub (don't have a switch handy, but I presume the hub will do essentially the same thing) between the DSL modem and the Vonage router.

I also made the DSL modem provide a local IP address instead of sending over the WAN IP.

I connected the hub output to the internet port of the router instead of the ethernet port1. Turned off dynamic routing on the wireless/vonage router. Power cycled it.

Vonage worked. No internet.

Should I have dynamic routing enabled, because there are still 2 "routers" on the network, aren't there?

My sorry attempt to update the diagram is attached.

Edit/Update: My bad. It looks like it is working fine! I am not sure why it did not work earlier, maybe just refreshing IP's or whatever. I could connect hard-wired (was never a problem) with 192.168.1.x and could browse the internet and now I am on wireless with 192.168.1.x and can browse the internet.

Thanks all! I will monitor the connections for a few hours and see how it behaves. Otherwise, I am pretty much set!


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## deltafowler (Aug 28, 2007)

Did you renew your IP on the computer by either rebooting it or "repairing" the connection?

What does the PC that cannot access the net show for:
IP - 
Gateway - 
DHCP Server - 
DNS Servers -

Post back results or request more information on how to obtain this information.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Did you renew your IP on the computer by either rebooting it or "repairing" the connection?
> 
> What does the PC that cannot access the net show for:
> IP -
> ...


I actually edited my earlier post, saying things look good so far. But let me monitor, especially the wireless part for a few more hours (took a break in the afternoon after getting it to work!  ) .. and I will post the information back.


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## deltafowler (Aug 28, 2007)

Good deal!
If possible, backup the router's settings to a file.
Should be an option from the configuration menu on the router.

Sorry it took so many tries to get it worked out.

With the single connection, the hub should do fine, as there's no traffic for a switch to manage anyway.

An 8 port hub is an 8 lane intersection with no traffic lights. Traffic bumps into each other until something gets through.
A switch adds traffic lights and directs traffic where it needs to go.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Good deal!
> If possible, backup the router's settings to a file.
> Should be an option from the configuration menu on the router.
> 
> ...


I *think* I am finding out the no-traffic-lights part now. Keep losing connection to the internet randomly, both wired as well as wirelessly. Maybe it is time to get that darn switch 

Edit: Nope, I was wrong, unfortunately it is not a hub but actually a 5-port switch. Still there seems to be dropping of "internet" access every few seconds. :-(


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## deltafowler (Aug 28, 2007)

Check the system event log on the problematic PC.
I'm wondering about an IP conflict for some reason.

Right-click My Computer icon and choose Manage.
Then go to Event Viewer.

You may also try power cycling all equipment, if you haven't already.
Been a lot tweaks and changes done in the last couple of days.


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## harsh (Jun 15, 2003)

The switch will work best down-stream of the one and only router. Putting it upstream will get the DHCP information from your ISP, not the router. The router doesn't respond to DHCP requests from the WAN side.

The answer continues to be to move the modem to where the wireless router works best. If worse came to worse, you might be able to use one Ethernet cable for both TCP/IP and phone traffic as 100baseT uses two pair and phone uses one pair.


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## lifeislife (Jul 23, 2004)

harsh said:


> The switch will work best down-stream of the one and only router. Putting it upstream will get the DHCP information from your ISP, not the router. The router doesn't respond to DHCP requests from the WAN side.
> 
> The answer continues to be to move the modem to where the wireless router works best. If worse came to worse, you might be able to use one Ethernet cable for both TCP/IP and phone traffic as 100baseT uses two pair and phone uses one pair.


Yes, I understand the best case is to move the modem close to the router. That is how I started. But partly to reduce the clutter, and partly to use some existing pre-wiring, I decided to go down this complicated path.

So let's recap the basic points/issues:

1. Wireless router is also a Vonage phone adapter, and therefore (for both reasons) it is hard to put it inside the closet in/near the control panel of the house. 
2. By putting the DSL modem in the control panel, I do have a theoretical chance to "light up" the wall jacks in 4 rooms with internet. The main purpose to even go there, is to be able to connect my DirecTV receiver to the internet. But there are other reasons too, like possibly connecting a Slingbox (whenever they finally release the SlingCatcher  ). I know both of these can use the wireless adapter but for a variety of reasons I would like to avoid that and use what I already have. 
3. In order to provide connectivity (LAN or WAN) to the 4 rooms I need to be able to split the DSL modem's connectivity somehow, router, switch, hub, whatever. 
4. Also, in order to be able to share files across devices, ideally all devices need to be on the same subnet (is it true?) and therefore I cannot have 192.168.16.2 talking to 192.168.1.2. I am not sure, but I think this is true.

As a result, I went deep into the crap in the garage and found an abandoned older router and started with a 2-router config. After much discussion it came down to maybe using a switch and a router.

The switch-router combination seems to be trouble because of conflicting IP addresses on the network (deltafowler, you were right. Again.) and so that idea seems to be falling off too.

You point out that the switch should ideally not be upstream from the router. But given that I want to spread the connectivity from the control panel as well as make a router available in the bedroom/office (for Vonage), how could the setup work?


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## lifeislife (Jul 23, 2004)

deltafowler said:


> Check the system event log on the problematic PC.
> I'm wondering about an IP conflict for some reason.
> 
> Right-click My Computer icon and choose Manage.
> ...


There were conflicting IP issues, you are right. The DirecTV device is connected directly to the switch and when I connected a computer, it tried to work with the same IP (192.168.1.64, which is the DHCP address given out by the DSL modem). At some point it looks like the wireless router was getting confused and stopping to do its work, and when I connect a computer explicitly, I was getting a Windows error message.

So it looks like a switch in general may not work because it does not divide a single "incoming" IP address into multiple ones. Right?


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## deltafowler (Aug 28, 2007)

The switch has no DHCP function. DHCP simply passes through a switch from the modem/router to a device.

With it cabled this way, the DirecTV receiver is being subjected to DHCP services from both the router and the modem.

I would try turning off the DHCP server on the router, allowing the DHCP server on the modem to manage the entire network.
Power cycle everything.
If everything works this way, fine.

If you lose connectivity below the router (wireless or Vonage), then try manually assigning an IP to the receiver and use one that is not in conflict with other devices anywhere on the network.
Note: write down the Gateway and DNS information before making the change, as they will have to be entered manually as well.


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## deltafowler (Aug 28, 2007)

The more I think about, the more I'm inclined to say go the easiest route and assign a manual IP to the receiver.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> The more I think about, the more I'm inclined to say go the easiest route and assign a manual IP to the receiver.


So the setup would be DSL modem -> Switch -> Router with the router not doing DHCP.

Or by assigning the DirecTV receiver a static IP.

The problem with assigning DirecTV a static IP is that it may not be the only device that connects to the switch. Won't the IP conflict happen when pretty much any time I have two devices connecting to the switch? If not, why is it only happening with the receiver/computer combination connecting?


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## deltafowler (Aug 28, 2007)

I'm thinking the receiver is getting its IP from the modem and the other devices are getting theirs from the router.

You may want to try turning off DHCP on the router and seeing if the clients plugged into it can still get their IP's from the modem. if they do, and the phones still work, it would be an easy fix.

Each device has a unique hardware identifier called a MAC address.
When a device needs an IP, it identifies itself to the DHCP server by the MAC address.
The DHCP server then issues the device a lease on an IP, based on its MAC address.
As long as that MAC is active, it will renew that IP from the DHCP server every time the lease expires.
If the Mac is not active (the device is turned off or removed), the DHCP server places that IP back in its pool of available addresses.

With everything that's been changed and re-configured on your network, it's possible that the receiver has managed to get a lease from one DHCP server and the PC from another, but they both have the same IP, and are thus in conflict with each other.

You can log into the router and view the active IP leases.
On my Linksys, it is under Status / Local Network / DHCP Clients Table


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## harsh (Jun 15, 2003)

lifeislife said:


> So the setup would be DSL modem -> Switch -> Router with the router not doing DHCP.


1. The router cannot NAT for anything that is on the WAN side of the router.

2. In order to accomplish both internal communications between devices and Internet connectivity at the same time, everything needs to be downstream of the router. Anything upstream of the router won't understand how to get to addresses behind the router no matter what you assign the IP number and subnet mask to.

3. Your ISP represents another router that you can't control the DHCP or DNS configuration of and it will answer any requests from the WAN side of the router.

4. You can certainly hard code the IP address, but the DNS servers can change and without DHCP, you won't know when it happens.


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## harsh (Jun 15, 2003)

deltafowler said:


> I'm thinking the receiver is getting its IP from the modem and the other devices are getting theirs from the router.


Of course this is what is happening. The problem is that the ISP will only issue one IP address per modem and the different devices keep stealing it from each other as they find out they don't own it any more. This is why it comes and goes unexpectedly.


> You may want to try turning off DHCP on the router and seeing if the clients plugged into it can still get their IP's from the modem. if they do, and the phones still work, it would be an easy fix.


The ISP is not your personal router. They will give your modem exactly one IP address any any device connected to it is going to have to compete for it.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> I'm thinking the receiver is getting its IP from the modem and the other devices are getting theirs from the router.
> 
> You may want to try turning off DHCP on the router and seeing if the clients plugged into it can still get their IP's from the modem. if they do, and the phones still work, it would be an easy fix.
> 
> ...


If I make DHCP off on the router, the wireless laptop cannot connect to the network. Also, the DirecTV receiver picked up the IP from the DSL modem and I could set it up with a fixed IP but I am afraid I will have conflicting IP's if two computers connect hard-wired too. Right?


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## lifeislife (Jul 23, 2004)

harsh said:


> Of course this is what is happening. The problem is that the ISP will only issue one IP address per modem and the different devices keep stealing it from each other as they find out they don't own it any more. This is why it comes and goes unexpectedly.The ISP is not your personal router. They will give your modem exactly one IP address any any device connected to it is going to have to compete for it.


So, the DSL modem (SpeedStream 4100) is not "DHCP-ing" like the home broadband routers do, is that right?

If that is the case, then there is absolutely no chance of my DSL modem -> Switch -> Router working.

If not, what can be done?


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## lifeislife (Jul 23, 2004)

harsh said:


> 2. In order to accomplish both internal communications between devices and Internet connectivity at the same time, everything needs to be downstream of the router. Anything upstream of the router won't understand how to get to addresses behind the router no matter what you assign the IP number and subnet mask to.


That's why I had a hard-wired router in between the DSL modem and wireless/vonage router. But in those cases I was seeing an intermittent problem with the wirelessly connecting devices, which were somehow getting 192.168.15.x (from the wireless router) addresses instead of 192.168.1.x (from the wired router) addresses.

Any idea how to wire it up ideally? (see the nice topo drawing done by deltafowler up at the beginning of this thread)


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## deltafowler (Aug 28, 2007)

harsh,
It is my understanding that this model modem features routing, NAT, and DHCP services for the LAN. It's an all-in-one device.

I could be completely wrong about that, as the modem can be configured a number of ways, depending on the ISP.

But the capabilities are there for it issue IP addresses to multiple LAN clients while it can certainly be DHCP client itself to the ISP or WAN.
http://shadow.sentry.org/~trev/adsl4200/docs/feature_matrix.pdf

lifeislife,
You can check this by shutting down the Linksys router and connecting your laptop to one of the Ethernet ports on the switch.
When the laptop is powered on, it should get an IP address similar to that of the DirecTV receiver, with the last octet being different only.
The gateway and DNS servers should identical and the DHCP server address should be the IP of the modem on the LAN side.

Rather than moving equipment around as described by harsh, is there any way that you could manipulate the cabling so that the DirecTV receiver is fed back from the Linksys router and the switch is removed completely?


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## deltafowler (Aug 28, 2007)

As for the ISP changing DNS servers and thus risking the loss of Internet connectivity to the receiver, that would be RARE.
My ISP and the other major provider in my area have used the same DNS servers for the last three years without them changing.

There are also many free alternative DNS servers available to the masses, so you do not have to be tied to the ISP's DNS.

http://www.opendns.com/ is one such service.
Not only is it free DNS, but you can setup filters to keep out the nasties.


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## deltafowler (Aug 28, 2007)

One last comment and I'm out of this one.
lifeislife,
You may want to consider running an ad in Craigslist for help with the setup.
I'm certain there are some college CS students who could get it all worked out in a matter of minutes.
Nothing like being there.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> harsh,
> It is my understanding that this model modem features routing, NAT, and DHCP services for the LAN. It's an all-in-one device.
> 
> I could be completely wrong about that, as the modem can be configured a number of ways, depending on the ISP.
> ...


deltafowler,

I tried that last night out of loss of hope for any other setup working reliably. I put the vonage router and my cordless phone base station inside the closet (man, the wife's going to be shocked with the cabling that suddenly sprouted out there!) and it worked just fine. Nothing special there, and of course I expected it to work well there.

I was not sure about the wireless range, and it looks like it worked ok. The main inconvenience was the phone being inside the closet. Also of course, now with the wireless being served from the panel, I cannot shut off the panel door, or have to find a way to stick the router on the outside of the panel. That is minor, though.


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## lifeislife (Jul 23, 2004)

deltafowler said:


> One last comment and I'm out of this one.
> lifeislife,
> You may want to consider running an ad in Craigslist for help with the setup.
> I'm certain there are some college CS students who could get it all worked out in a matter of minutes.
> Nothing like being there.


Thanks for all the help. I will try posting locally.


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## harsh (Jun 15, 2003)

The works first time and always solution is Modem->Router->Switch (if necessary).

It simply doesn't make sense to try to do it any other way.

You can draw and modify diagrams and theorize until we're all dead and gone and you'll still be scratching your head.


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## lifeislife (Jul 23, 2004)

harsh said:


> The works first time and always solution is Modem->Router->Switch (if necessary).
> 
> It simply doesn't make sense to try to do it any other way.
> 
> You can draw and modify diagrams and theorize until we're all dead and gone and you'll still be scratching your head.


So you are essentially ruling out the possibility of having two home network routers and file sharing among devices connected separately to those routers?

I think nothing is impossible, it is just a matter of time and money.


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## harsh (Jun 15, 2003)

lifeislife said:


> So you are essentially ruling out the possibility of having two home network routers and file sharing among devices connected separately to those routers?


You catch on... just not very quickly.


> I think nothing is impossible, it is just a matter of time and money.


As I said, if you brain one of the routers and turn it into a bridge or a switch, you could theoretically use two devices that started life as a routers. You can have only ONE device serving up DHCP which means only one router. Beyond that, all of those devices must be served (downstream) of the one and only functioning router.

While you were trying to re-tool sketches, I presented a logical proof that it cannot be done with multiple DHCP sources (Post #43).


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## lifeislife (Jul 23, 2004)

harsh said:


> You catch on... just not very quickly.


It was a rhetoric question which needed no response, but oh well.



harsh said:


> As I said, if you brain one of the routers and turn it into a bridge or a switch, you could theoretically use two devices that started life as a routers. You can have only ONE device serving up DHCP which means only one router. Beyond that, all of those devices must be served (downstream) of the one and only functioning router.
> 
> While you were trying to re-tool sketches, I presented a logical proof that it cannot be done with multiple DHCP sources (Post #43).


I actually do have it working with multiple DHCP sources, but my issue is that Vonage cannot provide me a telephone signal without something being present on the internet port of the "downstream" device which happens to be an all-in-one wired/wireless/vonage device.

So what I am faced with is not just a 2-routers-with-DHCP issue but more like 2-routers-with-DHCP-and-one-of-them-with-Vonage issue.

In any case, as deltafowler suggested I contacted someone locally who can help me set it up in person.


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## deltafowler (Aug 28, 2007)

Best way to do this one.
I'm sure I could get it going, but it needs some hands on.

Good luck and let us know how it turns out.
I'd love to see a finished and working drawing on it!

I like my drawings.
A picture is worth....


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## puckwithahalo (Sep 3, 2007)

> A picture is worth....


A lot of laughs if photoshopped correctly?


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## deltafowler (Aug 28, 2007)

See fark.com


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