This coordination of protocols creates a protocol family. By: Justin Stoltzfus Contributor, Reviewer. By: Satish Balakrishnan. Dictionary Dictionary Term of the Day. Machine Intelligence. Techopedia Terms.
Connect with us. Sign up. 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. The receiving device independently calculates the BCC and compares the two calculations.
From the Figure, it can be seen that each message has three parts:. SYN characters are used to establish synchronization between the sender and receiver. The message block follows the SYN characters. In this scheme, sender breaks each message into blocks of small messages for transmission. The trailer for each block consists of a block check character BCC.
Both the sender and the receiver generate distinct BCC during the transmission of message. At the end of receiving the trailer, the receiver compares its own BCC against that of the senders. If they are the same, this indicates the block has been successfully received without any error.
In this case, the receiver will reply using a positive acknowledge ACK. If the BCC of the receiver does not match that of the sender, the receiver knows an error has occurred during transmission, and will instruct the sender to retransmit the block by replying with a negative acknowledge NACK. This is also explained with the help of Figure. Bisync scheme has one major disadvantage in distinguishing between the control characters and the same text in a binary file.
If a control character like ETX occurs in the text field, the receiver would interpret this as the end of the text field and take the next character as the BCC. This is incorrect. This is overcome by using a technique called data transparency. If the receiver gets a DLE code, it knows the next byte is a control code. The receiver discards the DLE control character. What happens if the sender has a DLE code as part of the text block? In this case the sender precedes it with a DLE, and the receiver discards the first and uses the second as a data byte.
Dinesh Thakur is a Freelance Writer who helps different clients from all over the globe. For any type of query or something that you think is missing, please feel free to Contact us. Network protocols are the reason you can easily communicate with people all over the world, and thus play a critical role in modern digital communications. Neither local area networks LAN nor wide area networks WAN could function the way they do today without the use of network protocols.
Network protocols take large-scale processes and break them down into small, specific tasks or functions. This occurs at every level of the network, and each function must cooperate at each level to complete the larger task at hand. The term protocol suite refers to a set of smaller network protocols working in conjunction with each other. Network protocols are typically created according to industry standard by various networking or information technology organizations. While network protocol models generally work in similar ways, each protocol is unique and operates in the specific way detailed by the organization that created it.
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