What is the Difference Between Parallel and Distributed Computing

The main difference between parallel and distributed computing is that parallel computing allows multiple processors to execute tasks simultaneously while distributed computing divides a single task between multiple computers to achieve a common goal.

A single processor executing one task after the other is not an efficient method in a computer. Parallel computing provides a solution to this issue as it allows multiple processors to execute tasks at the same time. Modern computers support parallel computing to increase the performance of the system.  On the other hand, distributed computing allows multiple computers to communicate with each other and accomplish a goal. All these computers communicate and collaborate with each other by passing messages via the network. Organizations such as Facebook and Google widely use distributed computing to allow the users to share resources.

Key Areas Covered

1. What is Parallel Computing
   –Definition, Functionality
2. What is Distributed Computing
  –Definition, Functionality
3. What is the Difference Between Parallel and Distributed Computing
  –Comparison of key differences

Key Terms

Distributed Computing, Parallel Computing

What is Parallel Computing

Parallel computing is also called parallel processing. There are multiple processors in parallel computing. Each of them performs the computations assigned to them. In other words, in parallel computing, multiple calculations are performed simultaneously. The systems that support parallel computing can have a shared memory or distributed memory. In shared memory systems, all the processors share the memory. In distributed memory systems, memory is divided among the processors.

There are multiple advantages to parallel computing. As there are multiple processors working simultaneously, it increases the CPU utilization and improves the performance. Moreover, failure in one processor does not affect the functionality of other processors. Therefore, parallel computing provides reliability. On the other hand, increasing processors is costly. Furthermore, if one processor requires instructions of another, the processor might cause latency.

What is Distributed Computing

Distributed computing divides a single task between multiple computers. Each computer can communicate with others via the network. All computers work together to achieve a common goal. Thus, they all work as a single entity. A computer in the distributed system is a node while a collection of nodes is a cluster.

There are multiple advantages of using distributed computing. It allows scalability and makes it easier to share resources easily. It also helps to perform computation tasks efficiently. On the other hand, it is difficult to develop distributed systems. Moreover, there can be network issues.

Difference Between Parallel and Distributed Computing

Definition

Parallel computing is a type of computation in which many calculations or execution of processes are carried out simultaneously. Whereas, a distributed system is a system whose components are located on different networked computers which communicate and coordinate their actions by passing messages to one another. Thus, this is the fundamental difference between parallel and distributed computing. 

Number of computers

The number of computers involved is a difference between parallel and distributed computing. Parallel computing occurs in a single computer whereas distributed computing involves multiple computers.

Functionality

In parallel computing, multiple processors execute multiple tasks at the same time. However, in distributed computing, multiple computers perform tasks at the same time. Hence, this is another difference between parallel and distributed computing. 

Memory

Moreover, memory is a major difference between parallel and distributed computing. In parallel computing, the computer can have a shared memory or distributed memory. In distributed computing, each computer has its own memory. 

Communication

Also, one other difference between parallel and distributed computing is the method of communication. In parallel computing, the processors communicate with each other using a bus. In distributed computing, computers communicate with each other via the network.

Usage

Parallel computing helps to increase the performance of the system. In contrast, distributed computing allows scalability, sharing resources and helps to perform computation tasks efficiently. So, this is also a difference between parallel and distributed computing.

Conclusion

Parallel computing and distributed computing are two types of computations. The main difference between parallel and distributed computing is that parallel computing allows multiple processors to execute tasks simultaneously while distributed computing divides a single task between multiple computers to achieve a common goal.

Reference:

1.“ Parallel Computing.” Wikipedia, Wikimedia Foundation, 1 Feb. 2019, Available here.
2.“Distributed Computing.” Wikipedia, Wikimedia Foundation, 13 Feb. 2019, Available here.

 Image Courtesy:

 1.”Distributed and parallel systems” By Miym-Own work, (CC BY-SA 3.0) via Commons Wikimedia
2.”Functional levels of a manufacturing control operation” By Daniele Pugliesi-Own work, (CC BY-SA 3.0) via Commons Wikimedia