Exam 7: Data Link Control Protocols

It is usually desirable to have a physically separate communications path for control information.

In a data link control protocol,________ control is achieved by retransmission of damaged frames.

In the high level data link control frame structure the flag,address,and control fields that precede the information field are known as a ________.

Error control enables a receiver to regulate the flow of data so that the receiver's buffers do not overflow.

Most data link control protocols allow a station to cut off the flow of frames from the other side by sending a ________ message,which acknowledges former frames but forbids transfer of future frames.

The form of flow control where A and B are connected via a full-duplex link and A maintains a list of sequence numbers that it is allowed to send without receiving any acknowledgment and B maintains a list of sequence numbers that it is prepared to receive is ________ flow control.

The beginning and end of each frame must be recognizable for effective communication between two directly connected transmitting-receiving stations.

The sending station must not send frames at a rate faster than the receiving stations can absorb them.

________ control is achieved by retransmission of damaged frames that have not been acknowledged or for which the other side requests a retransmission.

High level data link control defines three types of frames,each with a different control field format.They are: information frames,unnumbered frames,and

Only one frame may be in the pipe at a time with sliding-window flow control.

An error detecting code calculated from the remaining bits of the frame, exclusive of flags,is the ________.

The receiver must be able to distinguish control information from the data being transmitted.

DLHC is a widely used data link control.

Containing virtually all of the features found in other data link control protocols,________ is a widely used data link control protocol.

The initiation,maintenance,and termination of a sustained data exchange require management procedures for the exchange.

________ control refers to mechanisms that detect and correct errors that occur in the transmission of frames.

The layer of control that provides error detection and error and flow control is known as a ________ protocol.

It is necessary to impose a layer of control in each communicating device that provides functions such as flow control,error detection,and error control.

Each ________ includes a field that holds the sequence number of that frame plus a field that holds the sequence number used for acknowledgment.