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connected to access point but no internet found

I have a friend with a T30 Thinkpad (Win XP Home, SP2) and a new Linksys Wi-Fi card who has a problem that just keeps coming up. We have no problem getting on the internet where there is unsecured access. As long as there is no authentication to go through, it's fine. But at several venues, where there is authentication, we always fail to get on. The signal can be nice and strong, but our attempts to log on always fail. The software says something like "Connected to Access Point, no internet found."

We have the correct password, we enter it using both 64-bit and 128-bit encryption, we watch closely to use the correct case for the letters. Nothing succeeds. To my knowledge, she has in fact never succeeded in logging on when authentication is required. (but this has been at only two places that I know of).

Can anyone suggest to us what is wrong here?? She's in Madrid now emailing me for advice.

thanks,

-g

Reply to
glenn
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"glenn" hath wroth:

WEP has a problem converting from ASCII to Hexadecimal. There are two (or more) algorithms for converting from ASCII to Hex. Windoze only supports one of these. If you use the Hex key, it should always work. Yes, I know that nobody likes to type 26 Hex characters.

However, if you have control over the access point configuration, I

*STRONGLY* suggest you switch to WPA encrytion and abandon WEP. WEP offers very little security as it is easily cracked.
Reply to
Jeff Liebermann

"Two (or more) algorithms"?? - that sounds pretty nuts, Jeff. You mean you can get different hex keys from the exact same passphrase depending on a version of WEP you have?? -or is it because of a bug?

I've passed this info to my friend and told her to try the hex key directly (getting it from someone who can log on ok). We'll see if that's it.

thanks for your input!

-g

Reply to
glenn

Exactly. The actual WEP key is in Hex. The access points and client software make it easy for users to "generate" a Hex key by providing a function that converts an ASCII text key into Hex. The problem is that since this is nowhere to be found in IEEE 802.11 specifications, they did it any old way they thought was interesting. The results are not consistent. There are two ASCII to Hex conversion algorithms that I know about, and I may have identified one more creative algorithm. When Windoze Wireless Zero Config asks for an encryption key, it goes through all the possible algorithms and protocols that it knows about until it finds a successful match. Unfortunately, it only supports one of the two ASCII to Hex conversion schemes. I haven't spent any time figuring out which manufactories and models support which algorithm. Don't assume that it's consistent among products from a given manufactory.

Sample code:

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Not really a bug since there's no standard way of converting from ASCII to Hex. However, the problem has been known for at least 8 years, and none of the manufactories appear interested in either fixing or documenting the problem.

It should work (famous last words).

Reply to
Jeff Liebermann

Jeff Liebermann hath wroth:

Sample output. The 40/64bit output is just the first five letters of the WEP key used to generate the Hex key.

C:\\wep> perl wep.pl abcdefghijklm

Converting ASCII string 'abcdefghijklm' to hexadecimal using common wifi driver algorithms.

40 bit Prism II (D-Link, Apple) key 0: 10 c2 1d 26 69 key 1: 75 04 af 53 68 key 2: 5a 65 4d 6e b2 key 3: 5e a2 f1 df ef

104 bit Prism II (D-Link, Apple) f343dcef2a6ea4ce5d63dabc4557b53a or for apple: f343dcef2a6ea4ce5d63dabc45

40 bit Hermes (Orinoco) 6162636465

104 bit Hermes (Orinoco)

6162636465666768696a
Reply to
Jeff Liebermann

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