Stupied network - Why can't it be friendly?

[Dan Williams]

On Tue, 2004-10-12 at 10:18 -0400, Charles R. Anderson wrote:
> On Tue, Oct 12, 2004 at 10:13:04AM -0400, Dan Williams wrote:
> > For your local crossover links question, NM supports static IP addresses
> > that you've configured with system-config-network (NetworkManager pulls
> > config info from /etc/sysconfig/network-scripts/ifcfg-* files), so if
> > you have that set up, your crossover connection between two computers
> > should work fine.
> 
> Does NetworkManager support automatic link-local addressing
> (169.254.x.x with duplicate IP detection/prevention)?  Then no
> preconfigured static addressing would be needed for ad-hoc connections
> like this.

Not at this time, but the big question is How Do You Detect That You
Need It.  The only thing that comes to mind right now is that if DHCP on
that link fails, then revert to automatic addressing.  That's at least
how Mac OS X does it, not sure about Windows.  However, the user
experience in that case is "I chose this network, why can't I get to the
Internet?" when DHCP fails on normal operation (ie, not using crossover
cables).

So, you have the specific case of using crossover cables, and then the
more general case that, if DHCP fails, the user can't get on the
internet at all.  Partial solutions:

1) Pop up a dialog stating that NetworkManager couldn't get
configuration info from the local network, and that it will now use an
"automatic" address.  But how many users know what that means and what
the behavior of "automatic" addresses is?  How do we address the user
who just wants to get connectivity, but can't because DHCP failed?  I
mean, "automatic" configuration is great for advanced users who know
what the heck they are doing, but its not "automatic" by any means for
all users.

2) Create the concept of an "ad-hoc" mode (supported by either wired or
wireless connections) that the user would have to _explicitly_ enable,
wherein NM would give interfaces "automatic" addresses.  We'd need to
figure out the user experience for this, how the menu applet would work,
whether the whole thing could be in ad-hoc mode, or whether one
interface could be in ad-hoc mode but another in infrastructure mode,
etc.

3) ???

I think (2) is a better path in the long run.  Currently, OS X's Airport
uses a "Create a network..." or some such menu item in the Airport menu
applet which switches the card to ad-hoc mode explicitly.  That's a good
feature for a later release :)

Dan