Which of the following contributes to increased read access performance on a fibre channel SAN?

Caching significantly contributes to increased read access performance on a Fibre Channel SAN (Storage Area Network) by storing frequently accessed data in a faster storage medium, such as RAM or SSDs. When data is retrieved, if it is already stored in the cache, it can be delivered to the requesting application or user much more quickly than if it had to be fetched from traditional disk storage. This reduction in retrieval time enhances overall read operations and improves the performance experienced by users or applications.

While other concepts like zoning, clustered storage, and Quality of Service (QoS) have their roles in storage networks, they do not directly boost read access performance in the same immediate way as caching does. Zoning is primarily concerned with security and traffic management, clustered storage focuses on availability and scalability, and QoS aims to manage and prioritize workloads to ensure fair resource distribution. None of these directly accelerates the retrieval of frequently accessed data as caching does.