I have often maintained that wired networks are fundamentally more secure than Wireless, purely because anyone can intercept wireless broadcast so your only line of defense is the encryption key. WPA is without doubt a more secure way to go wireless but a recent article on Slashdot.com shows that even this is under threat. The high processing capacity of some graphics cards has made brute force attacks on WPA keys a real possibility. The bottom line as I see it is that WPA is not yet broken, but make sure you have longs keys and secure pass phrases
I have heard of ways to crack WPA keys via packet flooding (Daniela seems to have touched on this issue in her thread). This method could potentially be a lot more efficient than a brute force method too. There are articles which show how to do this that aren't very hard to find which is a bit worrying.
My point is, with evidence available which suggests that Wireless 'security' really isn't as secure as we are led to think, what can be done to further protect ourselves from intrusion to our networks? Will we ever really be 'secure'?
As much as there are possibilities of future ability to crack wireless encryption such as WPA and WPA2 you have to consider that for every person that uses an up to date security scheme on their wireless (ideally WPA2) if you scan the area you are just as likely to find several surrounding networks that are not encrypted at all or are still using WEP. Short of someone being specifically targeted, the likelihood that someone will make the effort to build an array of 20 machines to spend a week cracking a personal wifi network is ridiculous. Why not just spend 5 min in Backtack 3 and get access to the next persons WEP network. I understand the principle behind questioning the security of WPA but in a practical sense I do not see a reason to feel unsecured for quite some time. Are we ever really secure? Not if you consider that for every, say, 1000 programmers you have designing a new encryption scheme, you probably have an online community of well over 1 million working against you.
I agree with your view Steve, that wired networks fundamentally being more stable and secure in comparison to wireless networks. There are ways in which to ensure that you dont make it easy for the attackers by making sure your key/password is a lot of characters including upper/lower class characaters, symbols, digits. However, it's inevitable, I dont think wireless networks will ever really be 100% secure. As technology advances it's only a matter of time when certain people with dedication find ways to crack them. I mean it happens all the time, with operating systems and programs such as Adobe Photoshop and Dreamweaver. How many of us can say we use a legit paid for version? If people can crack operating systems like Windows Vista who knows they could crack WPA? Theres people out there who have the extreme knowledge to be able to hack into wireless networks even with WPA2. How many of them are out there, will be limited. So the chances of us being on edge or feeling vunerable to having someone stealing our internet I think is slim.
The vast majority of people are still using WEP as there wireless encryption, therefore as 'mdtreibe' said, these will initally be the users which will be targeted. With video tutorials (packet flooding as Abid mentioned) describing how to crack WEP it seems pointless for anyone to want to spend so much money in trying to crack a WPA2 key.
Mike, you bring up a good point about the use of Backtrack and its ability to crack WEP networks. However, my take on this is that if it were really that easy and convenient for people to simply make use of a Linux Distro to crack/bypass a network key, everyone would be doing it.
To address your point about scanning the area and finding the majority of networks to be unsecured. I'm afraid I'd have to disagree. With the amount of news/campaigning going on these days, promoting wireless security and educating users of the benefits of using a network key; there has been a sudden increase in the amount of networks showing up as 'secured'. Certainly so since the time I first got wireless until now.
Again, I'd have to disagree with your statement about someone 'building an array of 20 machines to spend a week cracking a personal wifi network'. That may have been the case 5 years ago, but not now. With the possibility to make use of Nvidia and ATI GPUs along with apps which carry out dictionary brute-force attacks, there comes an extremely effective WPA/WPA2 cracking solution.
Still not convinced? Well here's a statistic to maybe sway your mind. It has been tested and proven that a Tesla S1070 can crack 52400 passwords a second. You have to admit, that's pretty impressive.
My point was not that any average Joe will be attempting to hack his neighbours Wifi, but that it is becoming increasingly easier as more tools and methods become available, for someone with malicious intent to penetrate the networks we deem as being 'secure'.