Lecture notes on introduction to computer networks and protocol

1. 1
Tutun Juhana
Telecommunication Engineering
School of Electrical Engineering & Informatics
Institut Teknologi Bandung
Introduction
Computer Networks

2. Reference
• TCP/IP Protocol Suite, Fourth Edition,
Behrouz A. Forouzan, McGraw-Hill

3. The Menu
• Theories
• Hands-on

4. A Brief History
• A network is a group of connected,
communicating devices such as
computers and printers
• An internet is two or more networks that
can communicate with each other
• The most notable internet is called the
Internet

5. internetsociety.org

6. Internet today

7. http://scoop.intel.com/what-happens-in-an-internet-minute/

8. PROTOCOLS AND STANDARDS

9. Protocol
• A protocol is a set of rules that governs
communication
http://www.teracomtraining.com/online-coursescertification/samples/lesson1104-protocols-andstandards.htm

10. • For communication to occur among
entities, they must agree on a protocol
We agree
to talk in
English…

11. • In computer networks, communication
occurs between entities in different
systems

12. • The key elements of a protocol
– Syntax
– Semantics
– Timing
A protocol defines what is communicated,
how it is communicated, and when it is
communicated

13. Syntax
• Syntax refers to the structure or format of
the data, meaning the order in which they
are presented

14. Semantics
• Semantics refers to the meaning of each
section of bits

15. Timing
• Timing refers to two characteristics
– When data should be sent
– How fast it can be sent

16. http://dev.opera.com/articles/view/http-basic-introduction/

17. Standards
• Standards are essential in
– creating and maintaining an open and competitive
market for equipment manufacturers
– guaranteeing national and international
interoperability of data and telecommunications
technology and processes
• Standards provide guidelines to manufacturers,
vendors, government agencies, and other
service providers to ensure the kind of
interconnectivity necessary in today’s
marketplace and in international
communications

18. • De facto standard ( “by fact” or “by
convention”)
– Standards that have not been approved by an
organized body but have been adopted as
standards through widespread use are de
facto standards
– Examples of de facto standards are MS Office
and various DVD standards

19. • De jure standards ( “by law” or “by
regulation”)
– Standards that have been legislated by an
officially recognized body

20. STANDARDS ORGANIZATIONS
Standards Creation Committees

21. Forum
To accommodate the need for
working models and
agreements and to facilitate the
standardization process, many
special-interest groups have
developed forums made up of
representatives from interested
corporations

22. Regulatory Agencies

23. INTERNET STANDARDS
• An Internet standard is a thoroughly tested
specification that is useful to and adhered
to by those who work with the Internet
• It is a formalized regulation that must be
followed
• There is a strict procedure by which a
specification attains Internet standard
status

24. • A specification begins as an Internet draft
• Upon recommendation from the Internet
authorities, a draft may be published as a
Request for Comment (RFC)
• Each RFC is edited, assigned a number, and
made available to all interested parties
• RFCs can be found at http://www.rfc-editor.org

25. Maturity Levels of RFC

26. RFC Requirement Levels

27. INTERNET ADMINISTRATION
ietf.org

28. • Internet Assigned Numbers Authority (IANA) and
Internet Corporation for Assigned Names and
Numbers (ICANN)
– IANA, supported by the U.S. government, was
responsible for the management of Internet domain
names and addresses until October 1998
– ICANN, a private nonprofit corporation managed by
an international board, assumed IANA operations
• Network Information Center (NIC)
– Responsible for collecting and distributing information
about TCP/IP protocols