Is it time to block all Microsoft protocols in the core?

Jack Bates jbates at brightok.net
Mon Jan 27 10:24:21 UTC 2003


From: "Darren Pilgrim"

>
> Sean Donelan wrote:
>
> > Should ISPs start blocking all Microsoft protocols in self-defense?
>
>
> I don't think it's so much of a problem of programs opening listen
> sockets as it is a problem of admins not properly controlling their
> networks and a certain software company pushing insecure features like
> printing over the internet that refuse to work from behind a firewall
> and have no direct proxy support.
>
>
This is the exact reason why any arguments to management to block NETBIOS
have failed. The reasons it is rejected are always the same:

a) We're not responsible for our users getting infected through their own
ignorance
b) Some of our users refuse to use VPN or lack the knowledge to effectively
use it and want to use NETBIOS services over the Internet
c) We buy Cisco 5200's in mass volume because they support our rural
networks better than any other modem bank we've tried (welcome to Oklahoma
:) and the processor on this wonderful piece of hardware will not support
the overhead of using a per user access-list methodology to filter the
majority and whitelist those who need the service.

If anyone has good recommendations for a strategy of getting around these
arguments, I'd love to hear it. I personally want to protect my users from
their own ignorance, particularly where NETBIOS is concerned. While win32
unbinds it from dialups in some cases, I'm still finding even the newer OS's
binding on the dialups. I'm not sure why this is, but I suspect that virus
infection in my network is coming from methods other than email; although my
email protections do have bugs (need to fix those this week).

Jack Bates
Network Engineer
BrightNet Oklahoma




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