Application layer, DNS, and domain names

The application layer, DNS, and domain names are the core concepts of this lesson, which focuses on the network architecture layer enabling programs and applications to communicate over the Internet.

The text introduces key application protocols—such as HTTP, SMTP, and FTP—and examines the workings of DNS, the system that translates human-readable domain names into the numerical addresses used by devices.
The lesson then explains the hierarchical structure of domains, distinguishing between TLDs, second-level domains, subdomains, and FQDNs.

Finally, the roles of nameservers, registrars, and registries are presented, clarifying how domain names are registered, managed, renewed, and administered on the Internet.

Bibliography

Primary sources

Mockapetris, P. (1987). Domain Names — Concepts and Facilities. RFC 1034. IETF / RFC Editor.

Mockapetris, P. (1987). Domain Names — Implementation and Specification. RFC 1035. IETF / RFC Editor.

Elz, R., & Bush, R. (1997). Clarifications to the DNS Specification. RFC 2181. IETF / RFC Editor.

Fielding, R., Nottingham, M., & Reschke, J. (2022). HTTP Semantics. RFC 9110. IETF / RFC Editor.

Fielding, R., Nottingham, M., & Reschke, J. (2022). HTTP/1.1. RFC 9112. IETF / RFC Editor.

Klensin, J. (2008). Simple Mail Transfer Protocol. RFC 5321. IETF / RFC Editor.

Postel, J., & Reynolds, J. (1985). File Transfer Protocol. RFC 959. IETF / RFC Editor.

IANA. Root Zone Database.

IANA. Root Zone Management.

ICANN. List of Accredited Registrars.

ICANN. Registering Domain Names.

Secondary sources

Kurose, J. F., & Ross, K. W. Computer Networking: A Top-Down Approach. Pearson.

Tanenbaum, A. S., & Wetherall, D. J. Computer Networks. Pearson.

Comer, D. E. Computer Networks and Internets. Pearson.

Peterson, L. L., & Davie, B. S. Computer Networks: A Systems Approach. Morgan Kaufmann.

Stevens, W. R. TCP/IP Illustrated, Volume 1: The Protocols. Addison-Wesley.

Liu, C., & Albitz, P. DNS and BIND. O’Reilly.

Mockapetris, P., & Dunlap, K. J. (1988). Development of the Domain Name System. ACM SIGCOMM Computer Communication Review.

Index

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