Mark is regarded as a Cybersecurity thought Leader. In 2002 Mark founded the Atlantic Canada High Technology Crime Investigation Association. In 2015 Mark published the first NIST Cybersecurity Framework Foundation course. Mark was trained by IBM on IBM’s AS400 and worked with IBM Global Services on a Red Team conducting penetration testing against off shore financial institutions.Mark has led the design and implementation of information security programs for many US and Canadian organisations using ISO. Mark led Central 1 Credit Union to become the first Canadian Bank to earn ISO/IEC 27001 Certification. During Mark’s work with BC Government 2008 he also led the Ministry of Finance Division Corporate Account Services to become the first Canadian Government entity to earn ISO 27001 Registration /Certification.

1. Block Cipher – Threats & Vulnerabilities
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Modern block ciphers are based on the iterated product cipher. In 1949 publication, Communication Theory of Secrecy Systems,
Claude Shannon analyzed product ciphers and suggested they would effectively improve security by combining simple substitutions
and permutations. Iterated product ciphers carry out encryption in multiple rounds, each of which uses a different subkey derived
from the original key.
Threats & Vulnerabilities
• Brute-force attacks - Due to a block cipher's characteristic as an invertible function, its output becomes distinguishable from a
truly random output string over time due to the birthday attack. This property results in the cipher's security degrading
quadratically, and needs to be taken into account when selecting a block size.
• Linear cryptanalysis - Linear cryptanalysis is a form of cryptanalysis based on finding affine approximations to the action of a
cipher. Linear cryptanalysis is one of the two most widely used attacks on block ciphers; the other being differential
cryptanalysis.
• Integral cryptanalysis - Integral cryptanalysis is a cryptanalytic attack that is particularly applicable to block ciphers based on
substitution–permutation networks. Unlike differential cryptanalysis, which uses pairs of chosen plaintexts with a fixed XOR
difference, integral cryptanalysis uses sets or even multisets of chosen plaintexts of which part is held constant and another
part varies through all possibilities.
• The development of the boomerang attack enabled differential cryptanalysis techniques to be applied to many ciphers that
had previously been deemed secure against differential attacks