What is a key characteristic of a tightly coupled system in a computing environment?

A key characteristic of a tightly coupled system is indeed the shared resources for fault tolerance. In tightly coupled systems, components are interdependent and often operate within the same machine or close proximity, which facilitates direct communication and resource sharing. This arrangement can enhance system reliability, as the failure of one component can be mitigated by the use of redundant resources or backup systems that are readily available within the tightly integrated architecture.

For instance, these systems might utilize shared memory or storage, allowing them to quickly recover from failures without significant downtime. Additionally, because the components are closely linked, they can efficiently coordinate and replicate data to ensure continuity of operations. This contrasts with loosely coupled systems, where autonomy and independence of components can lead to greater performance issues, as each unit operates more independently and may lack redundancy measures.

The focus on shared resources for fault tolerance makes tightly coupled systems particularly well-suited for critical applications that require high availability and minimal downtime, as they are capable of quickly responding to failures.