Re: A couple of minor issues with NM

[Matthew Saltzman <mjs ces clemson edu>]

On Sun, 24 Dec 2006, Timothy Murphy wrote:

> On Sunday 24 December 2006 17:54, Matthew Saltzman wrote:
>
> > > I checked my access point (a Linksys WRT54LG running dd-wrt)
> > > and there is no mention of "shared" or "open" that I can see.
> > > I am asked if I want to use a key, and if so what kind
> > > (WEP, WPA, RADIUS, etc).
> >
> > My Netgear config page has some Javascript and when I select WEP, it
> > reloads the page with an option for shared or open or automatic (which I
> > assume means the client decides).
> >
> > Does the dd-wrt documentation have anything to say?
>
> The "help" for Wireless=>Wireless Security says
> -----------------------------------------------------
> Security Mode
>
> Help
>
> Security Mode:
>    You may choose from Disable, WEP, WPA Pre-Shared Key, WPA RADIUS, or
> RADIUS. All devices on your network must use the same security mode.
> -----------------------------------------------------
>
> This seems perfectly clear to me.
> It is the NetworkManager choice of "open" or "shared" that I find confusing.
>
> As far as I can see, "open" means "no key" and "shared" means "key".
> Is that your understanding?

Except you know that WPA is not the same as WEP.  So there seems to be 
only one WEP mode, and I guess that would be open, but I'm not sure.

> It is the NetworkManager choice of "open" or "shared" that I find
> confusing.
>
> As far as I can see, "open" means "no key" and "shared" means "key".
> Is that your understanding?

There are two things that involve keys in your wireless link: 
authentication (are you allowed to connect to the access point) and 
encryption (is the data you send and receive over the air encrypted).  If 
you use WEP, then your data is encrypted.  In an "open" system, you are 
allowed to connect no matter what, but you can't send or receive data 
without a key in common with the access point.  In a "shared-key" system, 
you must have a key in common with the access point in order to connect at 
all and a key to share data. These could be the same, but then I don't 
think you get much additional security from a shared-key arrangement.


--
		Matthew Saltzman

Clemson University Math Sciences
mjs AT clemson DOT edu
http://www.math.clemson.edu/~mjs