Reading guidelines for Chapter 4 and Chapter 8, covering both E-mail security and PKI

Chapter 4: Key Distribution and User Authentication

This chapter gives an overview of three common standards for E-mail security. There is also an introduction to e-mail standards, RFC-5322, MIME, etc.

4.1 Remote User Authentication Principles

This is a general introduction to the principles of user authentication. Read carefully, except "The NIST Model for Electronic User Authentication", which can be read briefly.

4.2 Symmetric Key Distribution Using Symmetric Encryption

Read carefully this introduction, which explains the basic design alternatives and introduces the concept of Key Distribution Center.

4.3 Kerberos

Read the introduction part carefully.

The first part in the subsection "Kerberos Version 4" section explain the design of Kerberos in a step-by-step manner. Read carefully, and make sure you understand the basic design. It is important that you understand the fundamentals of Kerberos, with Authentication Server, Ticket Granting Server, tickets, and authenticators. In particular, how does Kerberos protect against replay attacks and stolen tickets?

The second part in subsection "Kerberos Version 4", starting from "Kerberos Realm and Multiple Kerberi," describes how a Kerberos system is organized, with concepts such as realms and principals. Read carefully.

Subection "Kerberos Version 5" describes the latest version of Kerberos. Read briefly, to familiarize yourself with the reasons why another version was defined. What are the shortcomings in and concerns with Kerberos version 4 that motivates version 5?

4.4 Key Distribution Using Asymmetric Encryption

Introduces the concept of public-key certificates. Read carefully.

4.5 X.509 Certificates

Read the subsection "Certificates" carefully to understand what information is present in a certificate.

Subsection "Obtaining a User's Certificate" describes how certificates can be organized in a hierarchy, and how they are verified step-by-step by following a chain of certificates. Read carefully.

Also read carefully about "Revocation of Certificates".

Read briefly the subsection "X.509 Version 3".

Introduces the concept of public-key certificates. Read carefully.

4.6 Public-Key Infrastructure

This section gives a brief introduction to PKI as defined by the IETF and the PKIX working group. Read carefully.

4.7 Federated Identify Management

Skip

Chapter 8: Electronic Mail Security

The first to sections is a repetition of Internet email. Read to refresh your knowledge!

8.1 Internet Mail Architecture

A background to Internal email. Read to recapitulate the fundamentals of how mail works on the Internet.

8.2 E-Mail Formats

A background to the format of email messages, MIME in particular. It is important to be familiar with the format of email messages in order to understand the integration of support for security in Internet email.

8.3 E-Mail Threats and Comprehensive E-Mail Security

Read carefully.

8.4 S/MIME

Read to get a general understand of the basic principles of S/MIME. All of it is relevant, although at a more detailed level than we cover in the course.

The subsection about "S/MIME Certificate Processing" discusses the S/MIME trust model and the procedure for certificate validation. This is related to PKI, where S/MIME represents the oligarchy trust model. Read carefully.

Other Reading

Kerberos is based on the Needham-Schroeder Symmetric Key Protocol. The textbook does not describe or discuss Needham-Schroeder. For an alternative introduction to Kerberos, look at the lecture slides about Needham-Schroeder.