Protocols

• A protocol is a set of rules that governs(control) data communications.
• A protocol defines what is communicated, how is communicated, and when it is communicated.
• The key elements of a protocol are :

1. Syntax,
2. Semantics
3. Timing.

Elements of Protocols

Syntax

• Structure or format of the data.
• Indicates how to read the bits – field delineation (border or boundary).
• Syntax should be same in sender and receiver for to communicate.

Semantics

• Interprets the meaning of the bits
• Knows which fields define what action
• Interpretation of the syntax should be same

Timing

• When data should be sent and what
• Speed at which data should be sent or speed at which it is being received

Standards

• Standards provide guidelines to manufacturers, vendors, government agencies, and other service providers to ensure the kind of inter-connectivity necessary in today’s marketplace and in international communications.
• Standards are essential in creating and maintaining an open and competitive market for equipment manufacturers and in guaranteeing.
• Data communication standards fall into two categories:
  • de facto (meaning “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. De facto standards are often established originally by manufacturers who seek to define the functionality of a new product or technology.
  • de jure (meaning “by law” or “by regulation”)
    Those standards by law or by regulation. These are the standards recognized officially by an Organization.

Standards Organizations
Standards are developed through the cooperation of standards creation committees, forums, and government
regulatory agencies.

Standards Creation Committees

• International Organization for Standardization (ISO): The ISO is a multinational body whose membership isdrawn mainly from the standards creation committees of various governments throughout the world. The ISO is active in developing cooperation in the fields of scientific, technological, and economic activity.
• International Telecommunication Union-Telecommunication Standards Sector (ITU-T): This committee was devoted to the research and establishment of standards for telecommunications in general and for phone and data systems in particular.
• American National Standards Institute (ANSI): Despite its name, the American National Standards Institute is a completely private, nonprofit corporation not affiliated with the U.S. federal government. However, all ANSI activities are undertaken with the welfare of the United States and its citizens occupying primary importance.
• Institute of Electrical and Electronics Engineers (IEEE): It is the largest professional engineering society in the world. International in scope, it aims to advance theory, creativity, and product quality in the fields of electrical engineering, electronics, and radio as well as in all related branches of engineering. As one of its goals, the IEEE oversees the development and adoption of international standards for computing and communications.
• Electronic Industries Association (EIA): Aligned with ANSI, It is a nonprofit organization devoted to the promotion of electronics manufacturing concerns. Its activities include public awareness education and efforts in addition to standards development. In the field of information technology, the EIA has made significant contributions by defining physical connection interfaces and electronic signaling specifications for data communication.