Protocols and network communications

Protocols and network communications

1. Basic aspects of communication

   • Networks may vary in size, shape and function
   • For communication to occur, devices must know "how" to communicate.
   • Communication begins with a message, or information, that must be sent from a source to a destination. Sending this message, either through face-to-face communication or through a network, is governed by rules called "protocols". These protocols are specific to the type of communication method in question.

2. Establishment of rules

   • The protocols must account for the following requirements:
     • An emitter and a receiver identified
     • Language and common grammar
     • Speed ​​and delivery time
     • Confirmation or acknowledgment requirements

3. Coding of messages

   • One of the first steps to send a message is to code it.
     • Coding is the process by which information is converted into another form acceptable for transmission.
     • The decoding reverses this process to interpret the idea.

4. Format and encapsulation of the message

   • When a message is sent from the origin to the destination, a specific format or structure must be used.
   • A message that is sent through a computer network follows specific format rules so that it can be delivered and processed.

5. Synchronization of the message

   • These are the rules of participation for message synchronization.
     • Access method
       • Computers must define an access method. Hosts in a network need an access method to know when to start sending messages and how to respond when a collision occurs.
     • Flow control
       • Synchronization also affects the amount of information that can be sent and the speed at which it can be delivered. If one person speaks too quickly, the other person will have difficulty hearing and understanding the message.
     • Waiting time for the response
       • Network hosts also have rules that specify how long a response should wait and what to do if the response timeout times out.

6. Protocol interaction

   • HTTP
     • it is an application protocol that governs the way in which a web server and a web client interact. HTTP defines the content and format of the requests and responses exchanged between the client and the server.
   • TCP
     • it is the transport protocol that manages the individual conversations. TCP divides HTTP messages into smaller parts, called "segments." These segments are sent between the processes of the server and the web client running on the destination host.
   • IP
     • It is responsible for taking the formatted segments of the TCP, encapsulating them in packets, assigning the appropriate addresses and selecting the best route to the destination host.
   • Ethernet
     • Is a network access protocol that describes two main functions: communication through a data link and physical transmission of data in network media.