Internet sharing with multiple interfaces.

[gregcan]

Hi,

I've been trying (with little success) to get a slightly convoluted network operational in my home.

I have numerous PC's and devices, some I'd like connected wirelessly, others I want to cable. My desired configuration is to have a "Gateway" PC connected to...

A:- Internet via 3G wireless broadband.
B:- Ethernet to WAN port of my Wireless Router.
C:- Wireless home network to provide printer and file sharing.

My problems so far have been in maintaining connectivity to the Internet once the wireless connects, and lack of reliable access to the internet via the wireless router from wireless PC's.

I have tried numerous configurations of router DHCP (on and off) for the LAN and Wireless, and ICS successfully allocated an IP address to the WAN. I've run out of ideas. I'm happy to disable the wireless on the Gateway PC if it's possible to share attached drives and printers via the WAN. The best I've achieved so far is "flaky" internet on the wirelessly connected PC's (as if DNS isn't working) with good internet at the gateway.

Any help would be greatly appreciated.

Cheers
Greg.

 

[00Roush]

First up... Welcome to the site!

So I am wondering why you want to have a "Gateway" (and ICS) in the network. Typical home setups (mine included) are generally setup going Internet source (cable modem, DSL, etc) -- Router (DHCP on) -- Switch -- computers/devices. Is your setup different due to getting your internet over a 3G connection? Is this just a card attached to computer instead of a cable modem type of device?

Just wanted to make sure I get a good picture of how the network is setup.

00Roush

 

[gregcan]

Thanks for the welcome!

Hi and thanks for the welcome!

Yes, you guessed it... My connection is via 3G card in a USB port on a small (Atom based) PC... Why you ask... My home is a 48' yacht so just about any other means of accessing internet is out. I have in the past used additional software on a dedicated gateway PC to share across a network via standard Ethernet switch to cabled PCs, and an AP for wireless machines. In this case though the PC with the 3G card also needs to be accessible to the rest of the network as it serves media and printer functions aswell.

So, I'm aiming for PC with 3G card sharing internet via router WAN port to wireless and wired LAN, while still remaining part of the LAN. As I mentioned earlier, if this can be achieved without having to use the wireless interface I'm happy to simplify things by disabling the wireless on that machine.

Cheers
Greg.

 

[overdrive31]

Disable DHCP on the router and plug into a LAN port not the WAN port of the router, from the gateway PC running ICS(will not work, since ICS DHCP pool uses the whole subnet there is no available address space for the static IP needed for the router to act as a access point). ..it will work by using an IP for the router not in the same subnet as ICS, you just will not be able to easily manage the access point settings.

You could try bridging the 3G connection to the ethernet port and plug it into the WAN port on the router with DHCP enabled, then connect everything to the router including the gateway PC with wireless.

You can also try Connectify(requires gateway PC to be running Windows 7), it supports sharing 3G/4G over ethernet and/or wifi. You then connect to a LAN port on the router with DHCP disabled in order to add more wired devices(or get a cheap switch), and have a choice of whether to use the wireless card on the gateway PC or the router as a wireless access point. Depending on the subnet used by Connectify, you will need to change the LAN IP on the router to something in the subnet(not required, unless you need easy access to manage the AP) and outside of the DHCP pool, that is if there is any address space left outside the DHCP pool.

 

[gregcan]

Bridging here I come!

Thanks overdrive,

I'll try your suggestions out and let you know how it goes!

Cheers
Greg.

 

[overdrive31]

Almost forgot, ICS uses the subnet starting with 192.168.0.1(Windows XP/Vista), and Windows 7 ICS uses the subnet starting with 192.168.137.1 by default. They both use DHCP pools covering the entire subnet, so my first suggestion while seeming the easiest, most likely will not work, you need a static IP for the router's LAN in the subnet and when the DHCP pool has no openings for a static assigned IP, it will not work.

You could make it work if you changed the LAN IP of the router to something like 192.168.2.1 to prevent an addressing conflict, then plug the ethernet into the WAN port with DHCP enabled. You could possibly get local networking(sans DNS and gateway address) using the wireless card on the gateway PC to join the subnet of the router to share stuff with the rest of the devices.

It might prove easier just to buy a CradlePoint or some other 3G router to share the connection.

 

[00Roush]

My opinion is the easiest setup for you is most likely going to be just having your gateway PC and no router. This is because the gateway PC is basically doing all the functions your router is doing. So now you have Internet --- Router 1 (Gateway PC) --- Router 2 --- Computers/devices. You could probably use this setup and just have everything (wireless and LAN clients) connect to Router 2 but you would not be able to access any shared files/printers on Router 1. So instead just take Router 2 out of the picture.

The other option I see is exactly what overdrive31 said... "buy a CradlePoint or some other 3G router to share the connection." So instead of having a 3G USB card that has to be plugged into a PC you have a 3G router that takes the place of needing your Gateway PC running ICS. You could then re-purpose the Gateway PC to share files and/or printers.

Hope that helps. Let us know how it goes.
00Roush

 

[claykin]

My vote is to purchase an "appliance" to handle your needs. I haven't used Cradlepoint, but I've done similar with a Zyxel USG. Cradlepoint seems to support more USB cellular modems. I'm sure there are others, just try to avoid typical consumer gear.

 

[overdrive31]

I had always thought a router turned access point needed to have an IP in the network subnet to work, guess it was just preferred to have it with an IP in the same subnet for configuration purposes.

It turns out that the access point doesn't need to have an address in the subnet for it to work, it technically is just a ethernet to wireless bridge/dumb switch.

So, my first suggestion I had thought wouldn't work with ICS will actually work just fine, you just will not have the ability to manage the access point settings without first manually assigning a static IP on a client to be in the access points own subnet, when done managing it, just set the client back to DHCP. This will require setting the LAN IP on the router/ap to something not located in either of the ICS subnets. eg. 192.168.10.1

 

[gregcan]

where to from here...

Hi Guys,

Thanks again for all the input... I'm trying to avoid purchasing any more gear (The minister for war and finance thinks I have too much geeky stuff already)... I'm also really keen to use the existing modem because it's dual channel and ridiculously fast.

I'm going to try the bridged connection idea first simply because it seems closest to what I'm trying to achieve. I had previously considered this option but an IT guru I worked with many years ago scared me off the option with his tails of unpredictable "Notworks"...

Report on findings to follow.

Cheers
Greg.

 

[overdrive31]

BTW the 3G/4G routers actually accept usb modems like you've got, rather than having internal radios like you may have thought.

 

[gregcan]

curiouser and curiouser...

Gents,

A small brick wall (that's a metaphorical brick wall not an actual one or any visible indication of one) seems to be preventing me from bridging my 3G card to the LAN port of my PC... once both interfaces are connected and selected there is no "Bridge Connections" option in the menu. I can select wireless and LAN and the option appears but as soon as I try to select the 3G card and any other interface the option disappears.

I've also noted that the router WAN port connected to the LAN port of the PC appears as "Unknown network and I can't change either the icon or the name...

Overdrive, thanks for the tip on the 3g card being able to e used in the router but it can't be done with either of my devices. The router I want to use has noUSB port, and the one that does have a port doesn't have the necessary software to drive the dual channel modem...

Keep the suggestions coming... I don't give up easily!

Cheers
Greg

 

[00Roush]

Gents,

A small brick wall (that's a metaphorical brick wall not an actual one or any visible indication of one) seems to be preventing me from bridging my 3G card to the LAN port of my PC... once both interfaces are connected and selected there is no "Bridge Connections" option in the menu. I can select wireless and LAN and the option appears but as soon as I try to select the 3G card and any other interface the option disappears.

I think only ethernet type devices can be included in a bridge...

So have you tried taking the router out and just using ICS on the computer the 3G card is connected to? You could still utilize the router as an wireless access point or as a switch if you wanted/needed.

00Roush

 

[overdrive31]

Well bummer, seems the easiest is still to buy an CradlePoint like router. In my last post I didn't mean you can use just any router with a usb port, I was talking about routers designed for 3G/4G, some routers with usb ports have firmware written only for file/printer sharing and not for the use of usb modems, but some of these routers can be modified with 3rd party firmware to support usb modems. In most cases you will not lose any speed you may be getting @ the PC currently, if you're so concerned with such. There are cheaper solutions than CradlePoint... please provide details on the modem model/service provider, PC OS, and router model to help further.