For example, an Apple iPhone can send an email to an Android device using a standard mail protocol. A Windows-based PC can load a webpage from a Unix-based web server using a standard web protocol. Protocols exist for several different applications. Examples include wired networking e. The Internet protocol suite, which is used for transmitting data over the Internet, contains dozens of protocols. These protocols may be broken up into four catagories:. Link layer protocols establish communication between devices at a hardware level.
In order to transmit data from one device to another, each device's hardware must support the same link layer protocol. Internet layer protocols are used to initiate data transfers and route them over the Internet. Transport layer protocols define how packets are sent, received, and confirmed. Application layer protocols contain commands for specific applications. For example, a web browser uses HTTPS to securely download the contents of a webpage from a web server.
An email client uses SMTP to send email messages through a mail server. Each protocol has its own method of how to handle data in the following situations. A protocol is a standard set of rules that allow electronic devices to communicate with each other. Protocols exist for several different applications. Examples include wired networking e. The internet and most other data networks work by organizing data into small pieces called packets.
Because protocols like Internet Protocol often work together in layers, some data embedded inside a packet formatted for one protocol can be in the format of some other related protocol a method called encapsulation.
In telecommunication, a communication protocol is a system of rules that allow two or more entities of a communications system to transmit information via any kind of variation of a physical quantity. Protocols may be implemented by hardware, software, or a combination of both. The process of communication refers to the transmission or passage of information or message from the sender through a selected channel to the receiver overcoming barriers that affect its pace.
The process of communication is a cyclic one as it begins with the sender and ends with the sender in the form of feedback. Data communications DC is the process of using computing and communication technologies to transfer data from one place to another, and vice versa. It enables the movement of electronic or digital data between two or more nodes, regardless of geographical location, technological medium or data contents.
A protocol is a set of rules and guidelines for communicating data. Rules are defined for each step and process during communication between two or more computers.
Networks have to follow these rules to successfully transmit data. Perhaps the most important computer protocol is OSI Open Systems Interconnection , a set of guidelines for implementing networking communications between computers.
The Importance of Standards. Standards provide people and organizations with a basis for mutual understanding, and are used as tools to facilitate communication, measurement, commerce and manufacturing.
Standards are everywhere and play an important role in the economy, by: facilitating business interaction. Standards are needed to assure safety of products, to ensure that products and materials are tailored-made for their purpose, promote the interoperability of products and services, facilitate trade by removing trade barriers, promote common understanding of a product.
What is a Protocol? Protocol is a set of rules that governs communication. The key elements of protocol are syntax, semantics and timing. Still, each serves as a key that unlocks a given network device or service. Different network protocols have been invented over the years, each attempting to support certain types of network communication. The three basic characteristics that distinguish one type of protocol from another are:. The common network protocols in public use belong to the Internet Protocol family.
IP is the basic protocol that enables home and other local networks across the internet to communicate with each other. IP works well for moving individual messages from one network to another.
It does not support the concept of a conversation a connection over which a stream of messages can travel in one or both directions. HyperText Transfer Protocol is used by web browsers and servers worldwide.
The internet and most other data networks work by organizing data into small pieces called packets. To improve communication performance and reliability, each large message sent between two network devices is often subdivided into smaller packets by the underlying hardware and software.
These packet switching networks require packets to be organized in specific ways according to the protocols the network supports. This approach works well with the technology of modern networks as these handle data in the form of bits and bytes digital 1s and 0s.
Each network protocol defines rules for how its data packets must be organized. Because protocols like Internet Protocol often work together in layers, some data embedded inside a packet formatted for one protocol can be in the format of some other related protocol a method called encapsulation.
Protocols typically divide each packet into three parts—header, payload, and footer. Some protocols, like IP, do not use footers. Packet headers and footers contain the contextual information required to support the network, including addresses of the sending and receiving devices.
Payloads contain the data to be transmitted. Headers or footers often include special data to improve the reliability and performance of network connections, such as counters that keep track of the order in which messages were sent and checksums that help network applications detect data corruption or tampering. The operating systems of network devices include built-in support for some lower-level network protocols.
Many smartphones support Bluetooth and protocols from the Wi-Fi family. These protocols connect to the physical network interfaces of a device, like its Ethernet ports and Wi-Fi or Bluetooth radios. Network applications support the higher-level protocols which talk to the operating system.
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