Automatic antispoofing rules on access servers.

[Lincoln Yeoh <lyeoh () POP JARING MY>]

I believe antispoofing filters won't really use up much CPU. So probably
one of the main reasons ISPs don't use them at their access servers is the
administrative cost in maintaining the rules.

However I recently noticed that Cisco has a feature which seems to make
this simpler to do.

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121newft/121
t/121t2/rpf_plus.htm

Do other major router/access server manufacturers have similar features?

If such features were more widely used, smurfing and spoofing stuff would
be a lot more difficult than it is now.

Are there any problems which would discourage use by ISPs?

Cheerio,
Link.