I have an existing WiFi network in my home: a Belkin router attached
to my DSL modem, and set up with 128-bit WEP encryption, generated by
a passphrase.  The network works fine for two desktops.

I recently bought a Sony Vaio V505EX notebook computer, which has
built in WiFi.  It recognizes the network, but does not give me the
option of entering a passphrase, or setting 128-bit encryption.  It
asks instead for a network key -- I don't know what that is.  (I'm
able to connect to a Starbucks hotspot with it, so the hardware is
working.)  How do I get this to work?

davidh1967-ga:

Thank you for your Question!

You made an excellent choice in purchasing the VAIO V505EX, it's a
beautiful notebook.

The notebook comes with Windows XP, which features built-in wireless
networking support. You have already encountered this, as you've come
to the cryptic and poorly explained 'Network key' entry field. This is
quite different from the Belkin router and adapters that you are most
likely using with the two desktop PCs. The Belkin equipment would have
come with their own client software for use with pre-XP operating
systems. That client software supports the idea of a passphrase to
generate the 128-bit key.

In the case of Windows XP, you need to supply the 128-bit key, in
hexadecimal format, as the network key. The best way to do this is to
change the 128-bit key on the router and the two desktop PCs to a key
that you can remember or write down.

The rules for creating a 128-bit key are actually quite simple. You
need to use 26 hexadecimal numbers. Hexadecimal numbers are
represented by the digits 0 through 9, and the letters A through F.
That is:

0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F	

which represents values from zero through sixteen. An example of a
128-bit key, therefore, could be:

0123456789ABCDEF0123456789

That's 26 characters long, using hexadecimal numbers.

When you enter the network key in XP, XP automatically recognizes
whether you have entered a 13 character key (64-bit encryption) or a
26-character key (128-bit encryption) and sets the WEP encryption
level accordingly.

It is annoying that Windows XP does not support passphrases, but as
the passphrase concept is not part of the 802.11b/g standards, and
since passphrase algorithms can be implemented differently by
different manufacturers, this is probably for the best.

Please let me know if you run into any problems setting up the WEP key
in your VAIO, using the Request Clarification button above.

Enjoy!

aht-ga
Google Answers Researcher

I did what you suggested and it worked -- thanks!  (FYI: my Belkin
manual says that a 64-bit key would be 10 hex characters.  This seems
odd, but it doesn't affect me since I'm using 128-bit.)

davidh1967-ga:

Thanks for the tip!

As for the 10 hex characters part; 64-bit WEP keys are actually 40-bit
with 24-bit initialization vector (similarly, a 128-bit key is 104-bit
with a 24-bit initialization vector). My reference to 13 above is a
typo, it should be 10 as per your Belkin manual. The 10 hex characters
form the 40-bit part, with the 24-bit initialization vector being the
responsibility of the wireless equipment (based on an algorithm
defined by the 802.11b standard). For the 104-bits of the 128-bit key,
you need 26 characters (104 / 4 = 26). I was focusing on 128-bit keys
in the Answer, so slipped up on the 64-bit info, sorry! It's a good
thing you are using 128-bit, so that my typo didn't cause any
problems!

Regards,

aht-ga
Google Answers Researcher