RE: IDS\IPS that can handle one Gig
From: Peter Schawacker (ps_at_tenablesecurity.com)
To: "'Andrew Plato'" <firstname.lastname@example.org> Date: Wed, 1 Jun 2005 10:41:04 -0700
I always enjoy reading your posts. Thanks for replying to mine. I've
answered some of your comments inline below.
I would be remiss if I were not to warn readers that (here comes the
"full-disclosure" statement...) I used to pimp IPS and VM for a certain
company and that I now pimp VM, SIM and related technologies for a different
This is a really important conversation, the IPS/VM balance problem. Let's
keep it going. Having worked with both, I for one would like to get more
thoughts about the relationship between IPS and VM out on the table.
From: Andrew Plato [mailto:email@example.com]
Sent: Wednesday, June 01, 2005 9:12 AM
To: firstname.lastname@example.org; email@example.com
Subject: RE: IDS\IPS that can handle one Gig
> Another option, and one that many organizations are beginning to
> is to forget the current, "fashionable" notions of IPS and return
> to basics -- to focus more closely on vunerability and information
> management. I believe that if you have a comprehensive, continuous
> and meaningful flow of information about the environment and an
> effective vulnerability remediation program, the need for IPS
> appliances and agents (band-aids) can be reduced dramatically.
I hear this every now and then from security people, and I think this is
an attitude borne out of lack of experience with IPS.
PES>> Actually, it is an attitude borne out of entirely too much experience
with IPS. (I won't go into detail on my experience, but you can google for
me if you'd like.)
I have yet to see an environment (and I am a consultant so I see
hundreds per year) where there is an effective patch and vulnerability
management that can keep pace with the exploits in the wild. Quite
simply, it is impossible to think you can keep a large enterprise
continuously patched and therefore resistant to the latest
PES>> I have seen a few environments that have deployed patch and
configuration management systems that are effective. I can't mention any by
name, but they're amongst the top 100 of the Fortune500. Granted, they are
On average, it can take 20 to 30 days for an organization to roll out a
single Microsoft Windows patch. That includes testing, troubleshooting,
and deployment. In 30 days, your environment could be crawling with all
sorts of filth thanks to unpatched machines.
PES>> Yes, on _average_ companies struggle mightily with patch roll-outs.
But not all companies take 20-30 days. My point is that patch management
can be done. Frankly, most IPS roll-outs fail also and for much the same
reasons as patch/config management. IPS rules require testing, although
folks tend not to do bother, just as most don't bother testing patches and
other changes. Let's also bear in mind that most shops don't test patches
before deployment -- at least in any sort of formal way.
PES>> The point of my last post, just to refine it a bit, is that the better
your Vulnerability Management (including patch and configuration management)
the less you need IPS. I suppose the converse is also true. I would
qualify my point by saying that VM and IPS are far from perfect, which is
why we ("we" being InfoSec practitioners) are constantly faced with weighing
trade-offs between them.
Furthermore, if you look at the timeline of when an vulnerability is
"discovered", then when an exploit hits the streets - that time can be
days, even hours. In that case, its still weeks before MS or anybody
releases a patch, and then even more time before you could patch all
your machines. In this case, even under reasonable, well controlled
situation most organizations are three to six weeks out from patching
systems when an exploit is released. That is a ridiculously long period
of time. A period where that environment could become infested.
PES>> Yep, the zero-day threat is real, but it's not the whole problem.
NIPS is but one arrow in the quiver and it has its own virtues and defects.
Furthermore, a "comprehensive, continuous and meaningful flow of
information about the environment" means eyeballs. Somebody needs to be
watching that meaningful flow of information. And while highly trained
security engineers are an important part of a security team - they won't
work 24 hours day. People are the most important part of information
security, but technology works longer hours.
PES>> Indeed, most security information management and VM systems are
useless and expensive -- but not all... (I'll spare you the commercial.)
People also make mistakes and miss things. Its insane to think a
security admin or a network admin has the time or concentration to sift
through mountains of data everyday. Nobody will do that job for long -
or do it well.
PES>> I couldn't agree more. Fortunately, there are ways to automate the
Now, with a good IPS deployment, I can load up a signature update
(hopefully released BEFORE the exploit hit the streets), and now my
entire network is secure from the new exploit. I go home and rest easy.
If I have host-IPS I can update all my workstations too. Now, my patch
management team has time to roll-out patches in a more controlled and
logical manner. They are not dashing around at 4AM trying to put out
PES>> Agreed. We're talking about a healthy, well-balanced IPS/VM
IPS gives people control over their environment. And well-run IT
departments have control over their equipment. They're not constantly
flailing around or giving themselves impossible tasks.
PES>> I think you're overselling IPS here, but I've sold IPS too, so I get
where you're coming from. The gist of what you're saying is largely true.
That much said, I agree that IPS is sometimes given unrealistic
expectations. For this, I point the finger squarely at the legions of
Blackberry pecking vendor reps and cell phone yacking volume resellers
who say things like "If you're not using <insert technology here>,
you're not secure!" (that's an actual line, from an actual ad I saw).
These people could care less about security, they just want to sell
something. So, they'll tell you anything you want to hear about an IPS.
And they rely on the ignorance of IT departments to fall for marketing
However, when you peel away the sales people, I sincerely do not think
IPS is some "fashionable notion." It's a serious and effective way to
proactively defend a network. I've have seen the benefits.
PES>> Don't cast aspersions on "fashionable notions"! :-) Just because an
idea is overblown doesn't mean it's entirely bad. These days it's just not
possible to sell any nascent technology, no matter how good it is, without
declaring it a panacea. It's just the nature of the InfoSec Marketing Beast
to which we are all in some way victims.
Andrew Plato, CISSP
ANITIAN ENTERPRISE SECURITY
3800 SW Cedar Hills Blvd, Suite 280
Beaverton, OR 97005
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GPG public key available at: http://www.anitian.com/corp/keys.htm
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