subnet LAN subnet structure

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GuruG

8 posts

Wannabe Geek

#63183 22-Jun-2010 11:00

Hi there I need some help adding to a WiFi set up and want to know if this new structure is possible:
I have a work LAN connecting to a subnet through BEFSX41 Linksys router to WRT54G Linksys & WAP54G for WifFi handheld devices.
I want to extend the WiFi range so have a new WRT54G to add on but can't cable it back to the subnet (it's too far away). Can I place this on the LAN and get data back to the subnet ?

So would look like this:
WRT54G(new) -> LAN -> BEFSX41 <- WRT54G(old) + WAP54G(old)

I have given the new device an IP address on the subnet range, but it will only respond when plugged into the existing WRT54G.

Thanks to any network officianodos

Oldhat

180 posts

Master Geek

Lifetime subscriber

#344707 23-Jun-2010 23:14

Most wireless routers can handle up to 10 devices connected wirelessly before you start getting bandwidth issues.

Just looking at your current hardware I would suggest changing the set up slightly. I'll leave it up to someone more network savvy, but my understanding is that LAN traffic and routers don't mix.

You may be better off trying WDS using the two WRT54G routers for the LAN. One of the main handicaps of WDS is that the wireless connection is shared between the wireless devices and the wireless communication between the routers. Normally this will mean a 50% reduction in throughput.

                                                 |--------WRT54G ~~WDS~~WRT54G
                                                 |              |                            |
                                                 |         Work PCs                 Work PCs
Internet---------BEFSX41----------|
                                                 |
                                                 |-------WAP54G
                                                                |
                                            Home PCs & Wireless Devices

This setup would cause potential problems if you have a VPN setup. One possible work-around would be to set the WRT54G up in a DMZ.

webwat

2036 posts

Uber Geek
+1 received by user: 145

Trusted

#344891 24-Jun-2010 14:05

We need to clarify a couple of things... A subnet is "virtual" part of a network at the IP layer that is basically a range of IP numbers, so for example the subnet mask 255.255.255.0 could create a subnet of 192.168.1.xxx. This IP subnet could be on the same LAN, a VLAN (Ethernet group where ports on your main switch/router arent allowed to talk directly to other ports on different VLANs) or a separate LAN (eg behind a router).

Since IP numbers are the way computers find each other on a LAN, it can allow you to setup security permissions on your servers for different ranges of IP numbers in sensitive parts of your LAN. Sometimes wifi is classified as a security risk and installed with a different IP subnet or VLAN in front of a firewall, so that wifi devices can easily be blocked from a secure network or separated from desktop PCs. The IP subnet is not a security feature by itself but the routers can protect whatever network is behind them.

If your main gateway is the BEFSX41 and doesn't have any special setting for the Wireless routers, so its probably all on the same LAN and makes no difference, but you really want to fix that. Its actually the secure parts of your network that need to be protected behind a router/firewall. Heres a suggestion for a generic network if your main router doesnt have a built in "wifi zone":

BEFSX41? (main internet gateway) ?> "untrusted" network (wifi + public network) ?> "trusted" network (work firewall) ?> work LAN.

If you have something like a monowall firewall running on an old PC, then it combines some of those functions by creating separate zones for "public", wifi, and "trusted" network.

Time to find a new industry!

ArcticSilver

731 posts

Ultimate Geek
+1 received by user: 148

#344936 24-Jun-2010 16:21

Would you mind drawing out your topology? (layout) of the network? and maybe in a different colour the device you want to add in, what you wrote above to me is a little unclear.

GuruG

8 posts

Wannabe Geek

#344965 24-Jun-2010 17:47

Oldhat had the layout pretty much right.

network layout

The last WAP54G is in repeater mode, not wired in.
I need more wifi coverage about 40m away, which by cable is around 90m.
Perhaps I'm using the wrong tools for this, but I thought I could add in another WRT54G to the network without having to wire it back to the existing WRT54G.
First thought was to join it to the LAN to get to the .200 subnet - didn't work
The new WRT54G I have is v7, which seems to be limited reading the web.

webwat

2036 posts

Uber Geek
+1 received by user: 145

Trusted

#347268 2-Jul-2010 12:49

Presumably you have a less secure network on your 192.168.1.x subnet (which is a WAN from the BEFSX41 perspective), hence the need to use the BEFSX41 to protect the 192.168.200.x subnet. The BEFSX41 has to do NAT to get traffic to 192.168.200.x because its not a routable address which only exists on the LAN side of the router, ie a LAN is not a public network.

If you dont want to buy 90m of cable and connect each end to a patch panel or jackpoint somewhere, then your new access point must connect on the LAN side of the BEFSX41.

Time to find a new industry!