Re: ROI on IDS/IPS products

[Stefano Zanero <s.zanero () securenetwork it>]

Jeremy Bennett wrote:

> This is a problem with the products, not the customers. The problem
> being that there is still too much IDS thinking inside the IPS. 

Funny, since an IPS is nothing more than an IDS that can drop traffic ;-)

Yes, I'm being humorous here, but really there is not that much
difference in the two things, except for the marketing and the extremely
different defensive posture: an IDS hunts for higher detection rates
even at the cost of some false positives, whereas IPS aim at extremely
low false positive rates.

However:

> So, I *should* be able to purchase an IPS, read the manual, configure it
> according to my own risk profile, and then leave it alone. High-risk
> activity should be blocked. Benign traffic should be let through.

And then villains should be brought over to justice, and the greater
good should prevail.

However, getting back to the real world, doesn't work. You cannot
configure "your risk profile" because there's no way on Earth to express
that sensibly in a single clicky and yummy web interface. You can
configure the system, activating and deactivating specific signatures,
and - sorry - you WILL need to know damn well what you are doing.

It is not just a problem with the products (and boy they are faulty), it
IS a problem with the customers. A huge one.

> Questionable traffic should be logged for later policy reviews. 

What would "questionable" mean ?

> If I do
> not have the ability to continuously monitor the device then I should
> not have to do that. The device should regularly download updates and
> apply them based on my configuration. 

Pray tell, how, exactly ? I think it's high time to stop thinking that
somehow an "expensive enough" box will be able to do our homework for
us. An IPS is a tool for applying specific signatures to traffic and
block specific forms of attacks. Relating that with policies and
weighing risks is a job for a human, and a skilled one, not for an
algorithm.

SZ