In this article, we will go through the concept of Encoding and Decoding the message in Communication Process in Distributed Systems in detail.
Encoding and Decoding in Communication Process:
Encoding refers to “Codes that are used to convert a body of information from one system to another.” The secret meaning of a code is represented by a set of characters, symbols, or signs. Coding, according to John Fiske, “Includes both signs and rules that govern how and when these signals are used, as well as how they might be combined to construct more sophisticated messages.” The following diagram clearly illustrates the effective communication process.
The encoder or source gives individuals structure to the message, idea, or information in the aforementioned process, i.e. proper encoding of the message in the mind of the individual, and then sends it to the destination or receiver. The receiver then interprets the message based on his prior experience. Therefore, no communication is possible without the source. As a result, it is the most crucial factor. However, it must be very straightforward and clear so that the receiver may grasp the receiver’s statements.
The communication process has been observed to be continuous. Because one encodes the message and the other decodes it, there is no end to it.
Decoding refers to the process in which the decoder decodes or interprets a message that has been encoded by a source using his experiences and intellect. The message has been kept simple and basic. As a result, the decoder will be able to quickly and easily decode the received message and send it back to the source. In other words, we can say that the communication process will be understandable, as the receiver will readily comprehend the simple and clear message, and will decode the message to the source using all of his fine sense. Decoding is the technical term for the receiver or destination.
The message must be clear, factual, and meaningful, and it must be crafted in such a way that listeners, readers, and viewers do not misunderstand the meaning and goal.
Why Encoding and Decoding in Communication Process is required?
The data in a message should be useful to the receiving process. While transmitting data from the sending process’s address space to the receiving process’s address space the program objects structure should be maintained. But this is not the possibility in the case of a heterogeneous system, as the sending and receiving processes are carried out on machines having different architectures. It is also a challenging situation in the homogeneous systems as well due to the following reasons:
- An absolute pointer value loses its meaning when transferring from one process address space to another. Hence, the software objects which use the value of absolute pointer cannot be transferred in their original form and will require representation in some other way.
- The amount of storage take up varies with different program objects. To be meaningful, a message should typically contain a variety of program objects, such as variable-length character strings, long numbers, small integers, and so on. In this instance, the receiver must be able to determine which program object is stored wherein the message buffer and also determine space utilization by each program object for the message to be relevant to the receiver.
Due to these problems Encoding and Decoding in Communication Process are carried out. Message buffers are used to store program objects after they have been transformed to a stream format appropriate for transmission. Encoding of message data is the name for this conversion procedure that takes place on the sender’s side. The received message on the receiver side must be converted back to the original program objects from the stream form before it can be further used. Hence, Decoding refers to reconstructing program objects from message data by the receiver.
Representations for encoding and decoding message data:
The Tagged and Untagged are the two representations for encoding and decoding message data:
- Tagged Representation: Here, the encoding is done on the type of each program object, and its value. In this representation, the coded data format describes itself quite well which helps the receiving process to check the type of each program object in the message using this manner.
- Untagged representation: The message data in an untagged representation simply contains program objects and contains no information about the kind of each program object. In this representation, receiving process must know in advance regarding the procedure of decoding the incoming data because coded data format is not able to describe itself.