Re: Limited or no connectivity @ school

On Wed, 3 May 2006 15:54:01 -0700, DB <DB@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

Again, because you are connecting to the access point and obtaining an APIPA
address (169.254.x.x) I don't think encryption is the issue. If that was the
case you would be seeing a "validating identity" message.

I don't think that you get the point about APIPA - the APIPA address is self
assigned by the computer, because it is not connecting to the DHCP server, or
not associating with the AP.

The WiFi term "connected" is misleading. After it is "connected", the WiFi
client has to be "associated" with an AP before it gets an IP address from DHCP.
Only then will the client have network / Internet access.

Chuck, I still have to disagree. Getting to the "limited or no connectivity"
definitely means they cannot obtain an IP address and therefore get an APIPA,
as I think we agree. I disagree with the rest. I don't think you would ever
see the "limited or no connectivity" message on an encrypted access point
that you don't have the key/certificate to. It would stop at the "validating
identity" stage. As far as APIPA is concerned, it makes little difference,
but that wasn't my point. To get to the "limited" message, a connection is
made to the access point. From that point it cannot contact a DHCP server,
but the "connection" has been made to the access point, just not to the
network itself. As far as I can see, there can be two causes, the AP is not
connected to the network or DHCP has been configured not to give addresses to
unknown machines.

Are you saying that there is a situation where a computer lacks the network
key/certificate to make the most basic connection to an access point yet
still bypassess the "validating identity" stage to request an IP address and
then arrive at the "limited or no connectivity" stage? If it exists, I'd
like to know what it is.

No, what I'm saying is that the computer assigns itself the IP address, after:
# It's been refused connectivity ("association") by the Access Point, OR
# It's been refused an address by the DHCP server, OR
# There is no DHCP server.

APIPA is self assignment of IP address. The computer detects that it has no
assigned address, so it assigns one itself, and throws up the "Limited or no
connectivity" message.
<http://support.microsoft.com/?id=220874>
http://support.microsoft.com/?id=220874
<http://nitecruzr.blogspot.com/2005/07/limited-or-no-connectivity.html>
http://nitecruzr.blogspot.com/2005/07/limited-or-no-connectivity.html

--
Cheers,
Chuck, MS-MVP [Windows - Networking]
http://nitecruzr.blogspot.com/
Paranoia is not a problem, when it's a normal response from experience.
My email is AT DOT
actual address pchuck mvps org.
.

Relevant Pages

  • Re: Limited or no connectivity @ school
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    (microsoft.public.windowsxp.network_web)
  • Re: repost - Intermittent DHCP failure?
    ... No connectivity problem has ever been observed when connecting ... >> ad-hoc network, that's set to use DHCP anyway, that could ... >indicates that the wireless connection is active and connected. ... >network that does have a DHCP server, can you have some nodes that have fixed IP ...
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