Re: firewalls and the incoming traffic problem

[Leonard Miyata <leonard () geminisecure com>]

The solutions to this problem does exist, but the traditional
'Red Book' 'Orange Book' view of network security has been
abandoned by the firewall community long ago. Bellovin and
Cheswick warned against the 'hard crunchy shell with the
soft chewy center' solution years ago in their 'Firewalls 
and Internet Security'.

The MLS viewpoint was designed for the traditional military
catagories of 'Secret', 'Top Secret' and 'UnClassfied'. The
hierarchy of a subject that contains multiple levels probably
would not apply to commercial applications. The concept of
'Multiple Single Levels' can be applied to a business model.
Instead of 'Secret', 'Top Secret' and 'Unclassified', you could
have 'R&D', 'Administration' and 'Marketing'. VPN channels can
be established to their remote Single Level counterparts, with
defence in depth DAC, I&A, Audit, and MAC (thats Mandatory
Access Control, not to be confused with the E-mail term). High
security levels would have physical and virtual isolation from
networks allowed public internet access. A combination of physical
network topology, plus  'Orange Book' Guards and Proxy Bastion 
Hosts would control cross level data transfer, and limit the 
amount of information exposed during a possible 'incident'.

With the current business environment for network security, I 
don't see 'Red Book' technology being accepted, but I can dream...


Personal Opinions Provided by
Leonard Miyata
aka leonard () geminisecure com
Gemini Computers Inc.