490 QMCS - Class Today
Handing back the exam Projects Certificates and Chaining SSL and "Spot the Plaintext"
March 2005
R. Smith - University of St Thomas - Minnesota
1
Exam
76 points total Median: 88% (-9 points); Lowest: 82% Let's work through the problems
Problem 2 first it's easy
Just about everyone got it I wanted to see physical security in sensible places I wanted to see access control policies/procedures Locks, access cards, whatever Specify who gets in and who is excluded
March 2005
R. Smith - University of St Thomas - Minnesota
2
Problem 1
Tradeoff study You don't list shared features! I.e. choose between jeep and Hummer
4WD Gasoline powered Internal combustion engine Seats for driver and passengers
Which is most common today for linking sites? If I didn't come away convinced, you got 4 points off. If you listed shared features, 2 points off
IDEALLY: 2 "real" reasons for/against each
Less than that, or wrong direction, and I took 4 points
March 2005 R. Smith - University of St Thomas - Minnesota 3
Problem 1 rough "answer"
Link encryption
Established technology (so says the book) Potential crypto protocol weaknesses (replay, etc.) Expensive to deploy renting dedicated links (so says the book) Expensive to add new links new hardware EVERYWHERE
IPSEC crypto
More complex technology (so says the book) Broader protections (anti replay, anti tamper) Cheaper to deploy just need an Internet connection Cheaper to expand just add the new site's hardware
March 2005
R. Smith - University of St Thomas - Minnesota
4
Problems 3 and 4
What are the 3 types/classes of firewall? Problem 3: how can the different classes be used by a government to information?
suppress Points for identifying `real' mechanisms Points for linking it to information worth suppressing Political items and commentary Culturally inappropriate material (porn)
Problem 4: how can dissidents or other troublemakers circumvent these 3 firewalls?
At least 1 practical example for each for getting access Not interested in plain old troublemaking
March 2005 R. Smith - University of St Thomas - Minnesota 5
Project Schedule
Team and project THIS WEEK
Tell me next Tuesday What you're doing; who you're working with
Three page Outline by December 4
Major `facts and elements' of the topic List of information sources you will use
Final Project Due last week of class
March 2005
R. Smith - University of St Thomas - Minnesota
6
Continuing with Certificates
Can someone tell me how a certificate works? How does Firefox/Explorer, etc, validate a server certificate?
Crypto credentials URL
How does `certificate chaining' work?
Commercial certification authorities Web of trust and confidence in keys
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