IDS mailing list archives

RE: Can Of Worms - Attack Mitigation Systems vs. Network IPS


From: "Bob Walder" <bwalder () spamcop net>
Date: Fri, 30 Jan 2004 10:20:46 +0100

Joel,

One of the most sensible and well thought out responses to this type of
thread I have seen so far. Excellent explanation on where these types of
products fit, and why it is so difficult and dangerous to try and
pigeonhole them exactly.

Instead, potential purchasers need to define their requirements and then
examine products that provide the required functionality, instead of
just looking at all those products that now have the "IPS" box ticked on
their marketing literature.

An example of how difficult it is to categorise these things came out of
our latest IPS report (www.nss.co.uk/ips) where we were asked afterwards
by one person why the Top Layer device received NSS Approved status when
it performed so poorly in our signature coverage tests compared to the
likes of TippingPoint, NAI, ISS, etc. 

My reply was that it would have been very unfair to compare the Top
Layer device directly against products from those other vendors and thus
rate it poorly as an "IPS", since we would define it more as an "attack
mitigator" - thus when you look at what the product is DESIGNED to do,
it actually does it very well - hence we felt it deserved the NSS
Approved.

The poor old purchaser needs to become adept at reading between the
lines and seeing beyond those "vendor comparison" checklists that all
vendors are so fond of creating to show their products in the best
light. This market is still very immature and so there are still genuine
differences in the way these devices are architected, which means that
different products are more (or less) suitable for different
environments and tasks.

Our report attempts to explain that as much as possible but it remains a
difficult task, and will do until these devices are well established,
adopt a "generic" feature set that begins to look the same across all of
them, and start to become commodity items.... But don't be holding your
breath for that just yet... :o)

Regards,

Bob Walder
Director
The NSS Group




-----Original Message-----
From: Joel Snyder [mailto:Joel.Snyder () Opus1 COM] 
Sent: 30 January 2004 04:14
To: Andy Cuff; focus-ids () securityfocus com
Subject: Re: Can Of Worms - Attack Mitigation Systems vs. Network IPS


Hmmm.  Well, I just handed in a huge story to Network World, 
comparing 
11 of these products, and I also divided them into "rate based" IPS 
(i.e., things which tend to not look at content very much) 
and "content 
based" IPS.

The problem with those characterizations is that there are products 
which do a little of both. For example, Top Layer is an outstanding 
rate-based IPS, but it also does content-based IPS.  Tipping 
Point is an 
outstanding content-based IPS, but it also does rate-based 
IPS.  (These 
are not the only examples, just two which come to mine easily).  And 
BOTH types of IPS do the same protocol anomaly stuff---it is easy to 
detect malformed TCP packets and LAND attacks, no matter 
what your area 
of specialty.  So both content-based and rate-based are also 
anomaly-detecting.  (this is why calling content-based IPS 
"signature-based" IPS is very incorrect)

I believe that, over time, the good IPS products will tend 
to include 
both technologies as they understand them better.

It is also, I believe, a severe mis-characterization to call every 
content-based IPS an "IDS with the IPS bit set."  For example, Check 
Point's InterSpect IPS (a very content-oriented IPS) would 
never do as 
an IDS; it's just not in its heritage. The reason that this 
statement is 
made is that IDS companies are ideally suited to do 
content-based IPS, 
ergo there are many IPS which *are* IDS with IPS 
functionality added. 
ISS is the most obvious example which comes to mind.

What will happen in the long run is IPS technology will be 
incorporated 
into all sorts of products.  I realize that there's a lot of 
incentive 
to try and pigeonhole products (Gartner specializes in that sort of 
destructive characterization), but it seems better to 
consider products 
against a 2-space or 3-space of features and functions and 
place them 
there: firewall-ish, or content-based IPS-ish, or rate-based 
IPS-ish, 
for example.  This way we avoid putting products where they 
don't belong 
or unfairly comparing products which aren't really designed with the 
same goals in mind.

jms


Andy Cuff wrote:

Hi Folks,
Please pardon the above pun but this is another of those IDS 
terminology issues that I'd like to thrash out to 
understand what the 
members of this list think.

Intrusion Prevention Systems are certainly the current 
flavor of the 
month, Gartner's death of IDS has added to the marketing 
fervor for 
vendors to have an IPS in their stable of products.  But 
what products 
fit into the category?  There seems to be an ever 
increasing number of 
DOS/Attack Mitigation Systems that are labelling 
themselves as IPS, 
therefore after some offlist consultation I'd like to see 
what list 
members feel about this statement that was passed to me by a 
kind-hearted individual last week

The main definition between NIPS and Mitigators would be 
Mitigators 
are designed to do one specific job - detect and mitigate against 
DOS/DDOS attacks and bilateral effects of worm activity. NIPS are 
designed to detect malicious traffic and drop the 
packet/stream. NIPS 
are not always necessarily good at mitigating DOS/DDOS attacks. 
Mitigators generally do not have the signature coverage to provide 
good NIPS functionality. NIPS are like IDS but in-line. 
Mitigators are 
like firewalls but designed to detect and prevent DOS 
attacks rather 
than enforce policy.

I have moved many of the attack mitigators from my list of IPS at 
http://www.securitywizardry.com/inline.htm to a new Attack 
Mitigation 
System page at 
http://www.securitywizardry.com/idsdosmit.htm >> of which 
I 
currently have 12 products listed

Thanks for any time you can devote to this cause.

take care
-andy
Talisker Security Tools Directory http://www.securitywizardry.com



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-- 
Joel M Snyder, 1404 East Lind Road, Tucson, AZ, 85719
Phone: +1 520 324 0494 (voice)  +1 520 324 0495 (FAX)
jms () Opus1 COM    http://www.opus1.com/jms    Opus One


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