LTM_B1

Communication (a)   , both local (within a building or building complex) and long distance, both voice and data, has been growing at a high and steady rate for decades.

The first item, (a)   , refers to the need to make efficient use of transmission facilities that are typically shared among a number of communicating devices.

To communicate, a device must (a)   with the transmission system.

All the forms of communication discussed in this book depend on the use of electromagnetic signals propagated over a transmission medium. Thus, once an interface is established, (a)   is required for communication.

Not only must the signals be generated to conform to the requirements of the transmission system and receiver, but also there must be some form of (a)   between transmitter and receiver.

Beyond the basic matter of deciding on the nature and timing of signals, there is a variety of requirements for communication between two parties that might be collected under the term (a)   .

(a)   are required in circumstances where errors cannot be tolerated.

(a)   is required to assure that the source does not overwhelm the destination by sending data faster than they can be processed and absorbed.

Next are the related but distinct concepts of (a)   . When more than two devices share a transmission facility, a source system must indicate the identity of the intended destination.

(a)   is a concept distinct from that of error correction. Recovery techniques are needed in situations in which an information exchange, such as a database transaction or file transfer, is interrupted due to a fault somewhere in the system.