Need to build a wireless network with roaming capabilities. How does this look?

[Icyice]

Hey guys! This is my first post on this forum, and I have a question about networking. I posted this in OCN, but I'd like more opinions.

An uncle recently bought a large house, and he asked me to help him setup his wireless network. The property is large, with 13,000 squared feet and two independent buildings: The main house and the guests house.

The modem/router his ISP provided him is just not enough to provide internet access to the whole property. There even are problems to have WiFicoverage in the main house. Because of this, a custom system is required.

My idea is the following:

* Install a powerful router, such as an Asus RT-N66U with DD-WRT as the main Router/Wireless Access Point somewhere in the house.
* Install two Linksys WAP300N Access points, both of them connected to the main router via Ethernet.
* Use the same SSID, security protocol and password for the Wireless network broadcasted by the router and access points, this to allow roaming between the access points while walking through the house.

This is the hardware I'm planning to use

Main Router: Asus RT-N66U with DD-WRT
Access Points: Linksys WAP300N

What I want to know is: What do I need to set up in this network, aside from the same SSID, Security protocol and password (And different channels on each AP) to allow for roaming?

For example, if I'm using an iPad with Skype, and I walk around the house, I want the iPad to automatically switch from the main router, to AP1 or AP2 to remain connected to my wireless network and not drop the call. At the same time, I desire to have the entire property with WiFi coverage.

Here's what the network map would look like

http://cdn.overclock.net/8/88/900x900px-LL-889b0676_map.jpeg

Is there anything I need to consider, to have this working, the way I intend it to? A friend told me that I need to assign different IP ranges to each AP. For example:

* In the main router, change its IP to 192.168.0.1
* In AP1 I'd have to change the IP range to 192.168.1.1
* In AP2, change it to 192.168.2.1

Is this correct? I thought AP's didn't assign IP addresses, that it was the router who had to do that.

One more thing: Should I go grab one of these AC monsters instead of the N router I listed?

Any extra input and/or opinions are welcome

 

[stevech]

see the FAQ here on the subject of increasing WiFi coverage.
The way to do this is to add access points (APs), each connecting to the one and only router in the network. Each AP is located as needed to improve coverage.
Each AP connects to the router via either
cat5 cable if any way possible
IP on power line a.k.a. HomeIP. Pair of $40 devices to use home AC wiring instead of cat5
MoCA - same ideas as above, but using existing TV coax outlets or ones you can more easily add than running cat5 cable

Using wireless in lieu of cat5 or one one of the above - is last choice. Always problematic.

A booming high power router will NOT cure the problem -because the transmitted power of the client devices becomes the constraint in this kind of "unbalanced" system.

ANY WiFi router can be re-purposed as an AP. The WAN port goes unused. There's a FAQ on how to do that on this web site.

You'll use just ONE subnet like 192.168.1.x. The IP address given to APs is just for admin purposes - doesn't affect traffic flows. Be sure to disable DHCP server in re-purposed routers, as per the FAQ. Don't use two IP ranges (subnets).

This is a common problem, so read up on this web site's FAQs and this forum and you'll see it's not too hard to accomplish.

 

[Icyice]

see the FAQ here on the subject of increasing WiFi coverage.
The way to do this is to add access points (APs), each connecting to the one and only router in the network. Each AP is located as needed to improve coverage.
Each AP connects to the router via either
cat5 cable if any way possible
IP on power line a.k.a. HomeIP. Pair of $40 devices to use home AC wiring instead of cat5
MoCA - same ideas as above, but using existing TV coax outlets or ones you can more easily add than running cat5 cable

Using wireless in lieu of cat5 or one one of the above - is last choice. Always problematic.

A booming high power router will NOT cure the problem -because the transmitted power of the client devices becomes the constraint in this kind of "unbalanced" system.

ANY WiFi router can be re-purposed as an AP. The WAN port goes unused. There's a FAQ on how to do that on this web site.

You'll use just ONE subnet like 192.168.1.x. The IP address given to APs is just for admin purposes - doesn't affect traffic flows. Be sure to disable DHCP server in re-purposed routers, as per the FAQ. Don't use two IP ranges (subnets).

This is a common problem, so read up on this web site's FAQs and this forum and you'll see it's not too hard to accomplish.

That's the reason why I plan to buy those two AP's for this project. And yes, the original idea is to connect them both to the main router via Ethernet CAT6.

So let me get this straight: The AP's will not assign IP addresses to the devices, right? That's what the router is meant to do.

Also, should I even consider getting the Asus AC router instead of the N router?

 

[coxhaus]

There is a limit on what can be done with voice traffic and consumer routers roaming. Web pages seem to work fine using multiple APs. You don’t have control over nearest APs using consumer gear. Voice traffic will drop when you switch APs with consumer gear.

There are many ways to handle DHCP but you cannot have 2 DHCP servers on the same network. Multiple physical networks can have multiple DHCP servers or you can have one central DHCP server with multiple scopes.

 

[PrivateJoker]

Yes, like @Coxhaus said your main router is the DHCP server, the other APs are pure APs (DHCP forwarders) and all the computers point to 192.168.1.1 as the gatway.

Just assign all your IPs statically (for the APs and such at least) and make sure your DHCP is set to only hand outs addresses outside that window of static assignments.

You're going to get the most range out of 2.4ghz (it's also worth looking at Ubiquiti & Engenius, they both make high powered APs).

The SSIDs are the same, on 2.4ghz use 20mhz channels only, same WPA2 encryption and p/w all around and same 802.11b/g/n/auto mode selected.

The transition will be pretty seamless but it is outside the realm of physics to have an uninterrupted skype video chat or movie streaming when switching between APs

 

[Nerre]

The problem with such solutions is that you will not get true roaming. Without centrally managed access points no client will be able to automatically switch to the AP with the strongest signal.

When a client first connects it will choose the strongest AP and then stay connected to it until it loses the connection completely. Then it will perform a new scan and connect to the now strongest AP. That is why connections are dropped when switching, it's not because of the switch but because the switch is not done until the connection has dropped.

 

[PrivateJoker]

The problem with such solutions is that you will not get true roaming. Without centrally managed access points no client will be able to automatically switch to the AP with the strongest signal.

When a client first connects it will choose the strongest AP and then stay connected to it until it loses the connection completely.

Part of that is true, you don't get "roaming" like 802.11r roaming, however in my own experience & testing with various firmwares on Apple, Asus, & Linksys hardware, every single client device I have will transparently switch to the strongest AP on the SSID (assuming you use same SSID for all APs). My auxiliary APs are always hardwired to same switch the main router/AP is on, and are DHCP forwarding no-NAT bridges. I can even be streaming high res video and move from one AP zone to another without interruption.

They will *not* switch to strongest AP automatically when using different SSIDs on multiple APs, they will wait until the connection is usually broken with the prior AP they were connected to. This is annoying because they will not then re-associate with the main AP until they have ranged out of the one you were last connected to. Even finessing the various settings in the AP wifi re timing, (DTIM, RTS, beacon, fragmentation threshold, etc) I was never able to make multiple SSIDs on different APs transfer smoothly.

If you go to a hotel or large commercial building with free wifi you'll see they tend to use one SSID and just blanket the building with different channels of that SSID.

 

[Icyice]

Part of that is true, you don't get "roaming" like 802.11r roaming, however in my own experience & testing with various firmwares on Apple, Asus, & Linksys hardware, every single client device I have will transparently switch to the strongest AP on the SSID (assuming you use same SSID for all APs). My auxiliary APs are always hardwired to same switch the main router/AP is on, and are DHCP forwarding no-NAT bridges. I can even be streaming high res video and move from one AP zone to another without interruption.

They will *not* switch to strongest AP automatically when using different SSIDs on multiple APs, they will wait until the connection is usually broken with the prior AP they were connected to. This is annoying because they will not then re-associate with the main AP until they have ranged out of the one you were last connected to. Even finessing the various settings in the AP wifi re timing, (DTIM, RTS, beacon, fragmentation threshold, etc) I was never able to make multiple SSIDs on different APs transfer smoothly.

If you go to a hotel or large commercial building with free wifi you'll see they tend to use one SSID and just blanket the building with different channels of that SSID.

So, based on your experience, my planned setup should work without too much hassle, right?

I still wonder, though: Should I bother with the AC router? I really have my doubts about getting that device.

 

[stevech]

11ac not suggested.

VoIP on WiFi... don't do it.