NIST Special Publication $800-175$B Revision $1-$ Guideline for Using Cryptographic Standards in the Federal Government: Cryptographic Mechanisms

NIST SP $800-175$B provides guidance to the $($US$)$ Federal Government for using cryptography and NIST's cryptographic standards to protect sensitive but unclassified digitized information during transmission and while in storage. The cryptographic methods and services to be used are discussed.

ITSP$\mathrm{.}40\mathrm{.}111-$ Canadian Centre for Cyber Security $-$ Cryptographic Algorithms for UNCLASSIFIED, PROTECTED A$,$ and PROTECTED B Information

ITSP$\mathrm{.}40\mathrm{.}111$ provides guidance on the use of Communications Security Establishment $($CSE$)$ approved cryptographic algorithms to protect UNCLASSIFIED, PROTECTED A$,$ and PROTECTED B information. For requirements on the use of CSE$-$approved cryptography to protect PROTECTED C and Classified information, refer to CSE's ITSD$-01$A: IT Security Directive for the Application of Communications Security using CSE$-$Approved Solutions.

Canadian Government $-$ Levels of Security

Description of different levels of security for sensitive government information and assets, organizations and personnel.

Questions

Q$1)$ As of $2021,$ which block cipher symmetric encryption algorithms are approved$/$common to both the Canadian and US governments for applying cryptographic protection $($i$.$e$.$ encrypting$)?$

Q$2)$ Which block cipher symmetric encryption algorithm is approved by the Canadian government for applying cryptographic protection $($i$.$e$.$ encrypting$)$ but not the US government?

Q$3)$ What is the principle reason DES$-56$ bit is no longer considered secure$?($Chapter $4-$ Cryptography and Network Security$)$

Q$4)$ Describe a simple application where DES$-56$ might be considered computationally secure$?($Review the definition$/$criteria of "computationally secure$"$ in Chapter $3-$ Cryptography and Network Security$)$