BCP for ISP to block worms at PEs and NAS

Christopher L. Morrow christopher.morrow at mci.com
Sun Apr 17 16:16:33 UTC 2005



On Sun, 17 Apr 2005, Randy Bush wrote:

>
> > On my Cisco-based SP network with RPMs in MGX chassis acting as PEs:
> > I have the ACL below applied on many network devices to block the
> > common worms ports,
>
> if you are a service provider, perhaps filtering in the core will
> not be appreciated by some customers.  of course, as a provider,
> you can choose what 'service' you are providing.  but, if you
> filter ports, it is not clear you are providing internet service.

one approach might be radius installed filters? some contract language to
allow 'customers' to request standard templated filters at little/no-extra
cost to them. Allow them to make the decision to filter themselves (where
'themselves' may be a dial reseller, of course).  Making them responsible
means when odd-application-12 comes along to utilize tcp/135 you won't
have to poke spot holes through your filters to permit this access.



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