Share internet connection over AirPort

[miyan]

I connect to the internet with an USB DSL modem. I want to share this connection over AirPort. I have a wifi WPA2 network which is provided by an AirPort Express. In the system preferences > sharing I can select AirPort, but have to create an unsecure WEP network. How can I share the internet connection over my existing secure WPA2 network. I don't want to create an extra unsecure computer-to-computer network but share internet over the WPA2 network for all computers that connect.

I hope you get what the problem is. I would be very thankful for any help or advice from you.

 

[wordmunger]

I think you're misunderstanding what "sharing" is.

If you want other computers to be able to connect to your airport express, all they need is the network name and the password.

Sharing is for when you want to use your computer as a way to extend your network.

For example, if you have another computer that doesn't have a wifi card, you can physically connect it to your computer that accesses the internet via the wireless network.

Or if you have a computer physically connected to the network, you can share its connection via its airport card.

Make sense?

 

[miyan]

If you want other computers to be able to connect to your airport express, all they need is the network name and the password.

Another computer, an iBook, can connect to the airport network. But how do I get internet to airport? I connect to the internet on a MacMini. How does this connection come into the air?

Thanks for your help!

 

[wordmunger]

Another computer, an iBook, can connect to the airport network. But how do I get internet to airport? I connect to the internet on a MacMini. How does this connection come into the air?

Thanks for your help!

I don't think you need the airport at all. Just use internet sharing through your Mac mini.

You might be able to share your internet connection with your airport express using ethernet from your mini. Then the airport express could provide the internet connection to other computers via wifi. I'm not sure this will work though.

You cannot connect a USB modem directly to the Airport Express. Another option would be to get an ethernet modem and connect that to the AE, which then provides internet service for all your computers.

 

[corbywan]

Just to be clear and not to overlook the obvious, your DSL modem has absolutely zero Ethernet on it? What make/model is it? Who is your provider? I'll bet they could provide a more normal box for you because that sounds weird to me to offer a customer a USB-only DSL modem.

 

[oordoo]

I'm new to this forum and say hello to everybody

the issue is not uncommon because it applies also to USB-only 3G mobile modems, as in my case
I succeded in doing what you need by avoiding Internet Sharing at all (by instance I.S. does not even allow devices on the Airport network to share files and printers) and applying instead and applescript like the following:

............................................................................................
do shell script "sysctl -w net.inet.ip.forwarding=1" with administrator privileges
delay 1
do shell script "natd -interface ppp0" with administrator privileges

delay 1
do shell script "ipfw add divert natd ip from any to any via ppp0" with administrator privileges
..............................................................................................
that means to activate a processing where all messages from/to LAN networks are NATed via the ppp0 connection (in my case ppp0 is the connection name of the USB modem showed by the ifconfig terminal command, you have to check if also with your modem has the same name)
With this all IP devices (PCs, MACs,satellitar decoder) attached to a router (wirelessly/WPA2 or Ethernet) are sharing the 3G internet connection