There is a global standard to how devices transmit and receive data in a communication network or even just two devices on a point to point connection. The ISO or the International Standards Organization has designed a set of rules for how communication of data should be carried out. These standards involve network service layers and user end function layers that ensure that you transmit and receive the data or information with no errors over physical digital equipment.
1. Network Layers
The Physical Layer – The primary focus of this layer is the physical and mechanical factors that transmit data from one point to another. This involves transmitting data bits to and from devices through specified physical connectors, types of wire or cable, and the type of signal.
- Data Link Layer - This layer controls and formats the information being sent and makes sure that it is free from errors.
- Network Layer – Controls the flow of information by putting it into data packets and finding the best route to deliver the data.
- Transport Layer – This layer breaks down the data into smaller packets for transmitting. They are all sent in sequence but take different routes so they could possibly arrive out of sequence.
- Session Layer – This layer establishes the connection between two users and also handles the termination of data transmission.
- Presentation Layer – Special character sets and graphics are defined so that they can be encoded for transmission and decoded upon reaching their destination.
- Application Layer – Pertains to the program that uses the communicated data with a set of standards to translate it into the final product.
2. Node functions in network protocols
Nodes can either be transmitters or receivers, and network protocols are put into effect to prevent these nodes from colliding with each other. In a situation where you have multiple nodes transmitting data, the protocols follow a method wherein nodes watch out for other transmitting nodes and only transmit when the network is free. But in some cases where collision is unavoidable, the network protocols ensure that the transmission is set back on course using time delays or ranking. Time delays will reset the colliding nodes and will transmit only when a node’s time delay has expired. By ranking nodes, only the higher ranked nodes will get to transmit first, and other lower ranked nodes will get to transmit only when the higher ranking nodes have completed transmission.
There are several variations to how these communication network protocols work in transmitting and receiving data in multiple nodes in a network, so they won’t conflict with one another in displaying or presenting data that is error free. This introduction to network protocols covered just a few points, and there are other protocols for communication networks but these are the widely used network protocols.