We can define a protocol as set of rules. So communication protocol is a set of rules which are used for communication. for example when we log on to MSN Messenger and we do chat with our friends then this is communication between us and protocols which are used for this are known as communication protocols.
Now we can define communication protocol as a set of rules which enable communication between two or more than two users in the form of voice, video and messaging.
TCP/IP is a communication protocol. Transmission Control Protocol is used to control the data exchanged between two ends these ends can be computers or any other device. It is guaranteed that data will be reached on the destination in the form in which it was sent from the source. Similarly SSL, USB are also known as communication protocols.
One another very popular communication protocol is SIP. Session Initiation Protocol (SIP) is used for initiating, establishing, terminating, managing any form (voice, video, messaging) of communication between two users. This is very popular protocol as Skype, MSN messenger, and many telephone card companies are using this protocol. Reason for its popularity is that it is so reliable and powerful that it can support large number of users at a time.
Answer. There are three components on which a communication system can be based. 1. Transmitter 2. Channel 3. Receiver Transmitter: Transmitter is responsible for transmitting or sending the data. This data may be in the form of analog data stream or digital data stream. 1. The Transmitter is responsible for multiplexing data. 2. The Transmitter is responsible for modulating data. 3. The Transmitter is responsible for Encryption of data. 4. Transmitter is also responsible for Encoding of data as well as compression of data. Channel: Data transmitted by transmitter travel through the specified channel. There are different types of channels through which we can transmit the data. Data travels through these channels to reach there destination receiver. List of these channels is given as below. 1. Copper cable. 2. Unshielded twisted pair / Shielded twisted pair(UTP/STP) 3. Air. 4. Fiber Optics. Channels have a vital role in proper transmission of data but unfortunately every channel has impurities i.e. Attenuation, Delay Distortion and Noise which will cause a substantial decrease in the speed of data traveling. Receiver: Finally, the receiver receives the transmitted data from the specified channel. This data may be in the form of analog data stream or digital data stream. 1. The Transmitter is responsible for multiplexing data. 2. The Transmitter is responsible for demodulating data. 3. The Transmitter is responsible for decryption of data. 4. Transmitter is also responsible for decoding of data as well as decompression of data.
There are three main component of data communication system. These are transmitter, receiver and transmission medium. The computer or device sending the data is called transmitter. The device or computer that receives the data is called receiver. The means through which data is sent from one location to another is called transmission medium. In electronic data communication, both the transmitter and the receivers are usually computers. A receiver can also be printer or a fax machine. The receiver and transmitter may be located within a building. In this case receiver and transmitter are connected by wire. If they are located at different locations, they may be connected through telephone lines, fiber optics or microwave. The coaxial cable, twisted pair cable, telephone lines, fiber optics and microwave acts as transmission medium.
The rules according to which data is transmitted and received are called communication protocol. Different component of communication system such as receiver and transmitter must strictly follow these rules for successful transmission of data. First rule is "how data is to be communicated". How transmitter and receiver will communicate with each other and how transmitter knows that the receiver has received the data.
Data communication software is a type of software that is used to correspond with other computers. The process of data traveling in the form of software is usually called protocol. This protocol is a set of rules for interchanging information between computers. These protocols define: • How the communication channel is established • How information is broadcasted • How errors are noticed and removed.
Key Elements of Protocol: Three key elements of a protocol are as follows: 1. Syntax Syntax refers to the structure or format of data. 2. Semantics Semantics refers to the meaning of each section of bits. It includes how should a particular pattern be interpreted and what action should be taken. For example, an address may identify the route to be taken or the final destination of the message. 3. Timing Timing indicates when data should be sent and how fast it can be sent. For example, a sender may produce data at 100 Mbps when receiver can process data at only 1 Mbps- The transmission will overhead the receiver and data will be lost.
Functions of Communication Protocols: The main functions of communication software or protocols are as follows: 1. Data Sequencing A process of breaking a long message into smaller blocks is called data sequencing. A long message is divided into smaller packets of same size. This technique reduces the amount of data that is retransmitted if an error is detected. 2. Data Routing Data routing is the process of finding the most efficient path between source and destination before sending data. This technique increases the efficiency of data communication. 3. Data Flow All computers are not equally efficient in terms of speed. 4. Error Control Error detecting and recovering is one of the main functions of communication protocol. It ensures that data is transmitted without any error. It also solves the problem if an error is detected.