Internet Edge and Defense in Depth

[robert at timetraveller.org (Robert Brockway)]

On Tue, 6 Dec 2011, Holmes,David A wrote:

> Some firewall vendors are proposing to collapse all Internet edge 
> functions into a single device (border router, firewall, IPS, caching 
> engine, proxy, etc.). A general Internet edge design principle has been 
> the "defense in depth" concept. Is anyone collapsing all Internet edge 
> functions into one device?

Hi David.  A principle of network firewall design has long been that you 
want to minimise services (proxy, etc) running there as they can be a 
vector for attack against the firewall itself.

In the end this is about risk analysis.  In most cases I would recommend 
against loading the firewall with additional functionality, for a variety 
of reasons.  In some cases it may make sense to do so.

This is completely separate to whether servers should even have a firewall 
or IPS in front of them.  That's another (interesting) discussion :)

Cheers,

Rob

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