What Is Network Protocol?

In the field of telecommunications, network protocol means a set of sequences that power must be interpreted by two or more machines or host (computer, telephone, printer, etc.) in the same way to establish an interpretative communication. Adherence to the protocol ensures that two software running on different machines can communicate properly, even if they were made independently.

To better understand a protocol (communication) is, in general, a set of rules that are set to establish proper communication (an Italian and a Chinese man could reach agreement in the use, for example, the English language to communicate ).

Service with and without connection.

When a client and a server started reporting it can exchange control packets before sending the actual data.

These procedures gave the handshaking prepare the two components to communication. These procedures are the basis, for example, TCP.

Exceptions may also be services that send data directly as in the case dell’UDP.

The majority of applications, including proxy servers, however, need to send data securely and reliably so that the handshake does just that task. We understand how the TCP connection, for example, is safer but also slower because trade is not only real data but also data services.

Protocol Levels

Each protocol normally applicable only some of the aspects of a communication. The various protocols are organized with a system called “levels”, and at each level a specific protocol is used.

The division is made in layers so that each of them using the services offered by the lower level and provides more “rich” to the higher. The different levels in a host communicate with each other through the interfaces called SAP (Service Access Point). Each layer talks only with those immediately above and with the next smallest layer. The protocols govern the communication between two entities instead of the same level, which serves to provide services to the higher level.

The various levels are organized into protocol stacks. The protocol stacks are a flexible way to combine components to create a service.

Structure used to fulfill certain tasks:

• Error control;
• Flow control;
• Fragmentation and reassembly;
• Multiplexing, so that higher layer sessions can share a single connection of the lowest layer;
• Establishment of the connection.

This architecture has advantages of conceptual and structural although some were opposed in a decisive manner as a thick layer duplicates the functionality of another layer repetitive.

For example, the ADSL service is delivered in different ways, the most common are called PPP over ATM (or Point to Point Protocol uses the services provided by ATM Protocol) and PPP over Ethernet.

The lowest level is called “physical layer” and handles the transmission of signals through the means of transport (cable, fiber optic, infrared, etc.). The highest level is called “application layer” and is what allows the user to create the message to communicate.

The division into levels is rather rigid in terms of specific protocols, and implementation levels are often deployed together in a single software module.

It is not said that two machines that communicate use the same protocol stack. For example, if you connect to the internet through a modem, you support the network layer IP over a PPP connection while the server you connect to the network likely supports IP over an Ethernet connection.

In a packet network each level of the “protocol stack” adds a header to packets through an operation called enveloping. The term also applies to some circuit-switched networks such as SDH, where the enveloping is a dedicated circuit to transmit control information.

The ISO

The International Organization for Standardization (ISO) in 1979 established the Protocol Open Systems Interconnection (OSI), with the intention of creating a standard for use in telecommunications networks around the world. In practice, however, the de facto standard that is commonly used in most networks, the TCP / IP, defined in RFC 1155. The key differences of the two standards are simple: the first was set to table-partisan organization, while the second is the work of those who physically built the first networks and expand the field. Furthermore, the standard ISO / OSI assigns a certain task at each level while the TCP / IP is more “elastic” and allows you to develop protocols that are more than a task-based.

Continued…

Related Posts:

• What Is Network Protocol | Part 2