Computer terms

Computer terms

Physical layer

Physical layer is the first layer in the OSI model consisting of seven layers. This layer comprises of the most fundamental networking hardware transmission technologies of a network. The physical layer provides compatibility between the mechanical or electrical interface and the physical medium. This layer, for instance, establishes the way to place a stream of bits from the data link layer on to the pins for a radio carrier, an optical fiber transmitter, or a parallel printer interface.

Data link layer

The data link layer marks out the data format on the network. The entire data transmitted via the network is compiled into a single frame that is executed at this stage. The frame is an unvarying means for transmitting the data together the error checking capacities and address information.

Network layer

The network layer administers the entire addressing concerns. This layer attends to the data packets, establishes the best route, and deals with the network issues, like data congestion. Also, the conversion of network names and addresses to the MAC addresses of the machines also takes place at the network layer. The network layer is also capable of allowing two distinct networks employing contradictory schemes of addressing for sending data to one another.

Transport layer

The fundamental operation executed at the transport layer is to receive data from the upper layer, divide it into small bits as per the requirement, and transmit the smaller, manageable packets of data to the lower layer. The transport layer, on the destination side, combines all the packets and again forms the original bigger unit. Also, this layer checks whether the order of the layers is correct when the data is received. In case an error is found in one of the packets, then a request is transmitted for the transmission of the packets.

Session layer

The session layer permits the applications running on the systems to communicate employing a session. The session layer first opens, then employs, and lastly closes the link of communication. Also, it serves as a dialog control method that administers who is capable of transmitting. This layer establishes who is capable of transferring at the present time.

Presentation layer

The presentation layer serves as a translator amid the network and the application layer. Dissimilar to the lower layers, the presentation layer is concerned with the semantics and the syntax if the transmitted data. Varying computer systems have the data stored in them in varying formats. For the purpose of permitting such computer systems to send and receive data to one another, the presentation layer converts the data into a standard format for being employed on the network.

Application layer

The application level imparts services which directly shore up the users' applications, like the database access, file transfer, e-mail, and user interface. The application layer provides the applications with the access to the network by means of the lower layers. Also, it transfers files amid the computers. Some computer systems have the file names stored differently or they denote text lines ...