Names and Directories Introduction

Names may not be the most obvious part of distributed systems, but distributed systems depend on naming. The World Wide Web, for example, is made possible by a global namespace that allows anyone to publish and anyone else to find it. Service identity is about more than names, but we name almost every object around us and so names become one of the most common attributes stored with an identity.

Once you’ve named a bunch of objects, you want to be able to find them. This is called discovery. Directories are one of the fundamental building blocks of discovery. As a result, distributed systems are full of directories. There are directories for files, directories for email addresses, directories for domain names, and even directories for running processes. The simplest directories associate a name with something else, such as a file, address, IP number, or process.

This lesson will discuss names, discovery, directories and the role that these play.

Lesson Objectives

After completing this lesson, you should be able to

  1. Distinguish names, namespaces, and addresses and describe the importance of each.
  2. Understand URIs as an example of names and namespaces.
  3. Explain the purpose of directories and directory services and how they relate to names.
  4. Describe the purpose of directory aggregating and distinguish methods for achieving it.
  5. Explain domain name service (DNS) and understand its importance in distributed systems.,
  6. Understand the problem of name discovery and methods for discovery.

Required Reading/Viewing

Additional Resources