I have had a couple of people ask me how to connect their Macs to Wireless networks (WLANs) so I threw this post together to be a point of reference and to help them out.
First off, the easiest way of connecting is to use DHCP – DHCP is a way of automatically configuring computers on a network. Whether you will be able to use DHCP will depend on the configuration of the wireless router you are connecting to. Many of them will be configured as dhcp servers – to serve the network configuration to their clients, in which case, all you have to do is select “Using DHCP” in the IPv4 dropdown in Network -> Airport -> Configuration -> TCP/IP
Strength of signal isn’t really a factor in serving pages (unless the strength drops to zero obviously!). If you have any signal at all, you should be able to browse. If you are connected but can’t view web pages it is most likely to be a dns issue. A way to test this is to open Terminal (Applications -> Utilities -> Terminal) and type “ping 22.214.171.124” – that’s the ip address of http://www.google.ie and it responds to pings by ip address. If you get a response, you are connected to the Internet. To stop the ping, hold down the ctrl key and hit the z key. Note – you can also use the Ping tab of the Network Utility app in OS X (Applications -> Utilities -> Network Utility) to do this.
If you do have a connection and want to check if your dns is set correctly, type in “ping http://www.google.ie”. If you get a response, you should now be good for browsing. If you don’t get a response, you probably have a dns settings problem.
Most wireless routers can act as dns servers, so if you have a dns problem, check the ip address of the router in the Airport TCP/IP config screen and add it to the DNS Servers field.
If you still have a problem, then the wireless router isn’t set as a dns server. In this case it is a little more difficult – you need to know who the ISP of the wireless router is and add their dns server’s ip address to the dns server field. Now, you can add as many servers as you want to this field, so if you can get a list of the major ISPs dns servers, it might be well to add them to this field – it shouldn’t be too hard to get this info – Google for it, or ring the ISPs helplines!
If that fails, move on to the next wireless spot – it is probably not worth wasting any more time on this one!
If you have a good dns connection (i.e. pinging http://www.google.ie responds) and you still can’t browse, then it is likely a browser config issue. Make sure there are no Proxies set in the browser, try resetting the browser to default settings, or try another browser.
I think this should cover you for most eventualities – if there is anything I have missed, feel free to let me know through the comments and I will update this post.