Question

For file storage, systems are faced with the goal of getting the most out the hardware at its disposal. Software solutions are employed in order to overcome existing hardware limitations.

Compare and contrast the distributed system architecture to the centralized and decentralized architectures. Under what circumstances would each one of these architectures would be most ideal?

Answer 1

Distributed Systems

A distributed system does not have a single centralized node. In distributed systems users have equal access to data. It helps in sharing ownership of data. The hardware and softwares are also available to the users which help in increasing the horizontal and vertical scaling of resources. There is an individual failure of components. It is difficult to set up.

They are helpful in online gaming and SOA based systems. Internet is also a good example of it.

Disadvantage

• Difficult to reach to a unified solution i.e consensus
• Difficult to get the global view of system as there is no global clock

Centralized Systems

In centralized systems there is a client-server architecture in which one or more nodes are connected to a centralized server. It is used in many organisations. It uses global clock. Only vertical scaling is possible.If central component fails then entire system fails. It is easy to set up.

These are used in universities,institutions etc.

Disadvantage

• Bottleneck occurs when there is high traffic. Denial of Service takes place when there is a lot of traffic.
• Frequent failure occurs
• Less possibility of data backup.

Decentralized Systems

In decentralized system each node takes its own decision and the aggregate of the decisions is the final behavior. There is no global clock and there are multiple central units. One central node failure causes a part of system to fail not the whole system. Vertical scaling is possible each node can add resources to increase the performance of system.

It is used in Bitcoin etc.

Disadvantage

• Regulation of nodes is difficult
• Sometimes there is a problem of coordination
• Not suitable for small systems