Link level: In the hierarchical structure of a primary or secondary station, the conceptual level of control or data processing

Data processing

Computer data processing is any process that a computer program does to enter data and summarise, analyse or otherwise convert data into usable information. The process may be automated and run on a computer. It involves recording, analysing, sorting, summarising, calculating, disseminating and...

 logic that controls the data link

Data link

In telecommunication a data link is the means of connecting one location to another for the purpose of transmitting and receiving information. It can also refer to a set of electronics assemblies, consisting of a transmitter and a receiver and the interconnecting data telecommunication circuit...

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Note: Link-level functions provide an interface between the station high-level logic and the data link. Link-level functions include (a) transmit bit

Bit

A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...

 injection and receive bit extraction, (b) address

Network address

Network address may refer to:*Base address*Classful address*IP address*IPX address*Logical address*Network layer address,*X.25/X.21 address*MAC address-See also:*Autonomous system *Host address*Link layer*Subnet mask...

 and control field interpretation, (c) command

Command (computing)

In computing, a command is a directive to a computer program acting as an interpreter of some kind, in order to perform a specific task. Most commonly a command is a directive to some kind of command line interface, such as a shell....

 response generation, transmission

Transmission (telecommunications)

Transmission, in telecommunications, is the process of sending, propagating and receiving an analogue or digital information signal over a physical point-to-point or point-to-multipoint transmission medium, either wired, optical fiber or wireless...

 and interpretation, and (d) frame check

Cheque

A cheque is a document/instrument See the negotiable cow—itself a fictional story—for discussions of cheques written on unusual surfaces. that orders a payment of money from a bank account...

 sequence

Sequence

In mathematics, a sequence is an ordered list of objects . Like a set, it contains members , and the number of terms is called the length of the sequence. Unlike a set, order matters, and exactly the same elements can appear multiple times at different positions in the sequence...

computation and interpretation.