Distributed System

https://www.techopedia.com/definition/18909/distributed-system

A distributed system is a network that consists of autonomous computers that are connected using a distribution middleware. They help in sharing different resources and capabilities to provide users with a single and integrated coherent network.

The key features of a distributed system are:

• Components in the system are concurrent. A distributed system allows resource sharing, including software by systems connected to the network at the same time.
• There can be multiple components, but they will generally be autonomous in nature.
• A global clock is not required in a distributed system. The systems can be spread across different geographies.
• Compared to other network models, there is greater fault tolerance in a distributed model.
• Price/performance ratio is much better.

The key goals of a distributed system include:

• Transparency: Achieving the image of a single system image without concealing the details of the location, access, migration, concurrency, failure, relocation, persistence and resources to the users
• Openness: Making the network easier to configure and modify
• Reliability: Compared to a single system, a distributed system should be highly capable of being secure, consistent and have a high capability of masking errors.
• Performance: Compared to other models, distributed models are expected to give a much-wanted boost to performance.
• Scalability: Distributed systems should be scalable with respect to geography, administration or size.

Challenges for distributed systems include:

• Security is a big challenge in a distributed environment, especially when using public networks.
• Fault tolerance could be tough when the distributed model is built based on unreliable components.
• Coordination and resource sharing can be difficult if proper protocols or policies are not in place.
• Process knowledge should be put in place for the administrators and users of the distributed model.