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

Zoning is a security and isolation feature on Fibre Channel SANs that controls which HBAs can communicate with which storage ports; it does not affect read speed.

Clustered storage improves capacity, availability, and fault tolerance across multiple nodes but does not inherently accelerate individual read operations.

Storage caching uses fast media such as RAM or SSDs to retain copies of frequently accessed data blocks. When a read request arrives, the cache controller serves the data from fast cache instead of retrieving it from slower HDDs, dramatically reducing latency and increasing throughput. This is the primary hardware and software mechanism used in SAN controllers to boost read performance.

QoS (Quality of Service) prioritizes and throttles traffic between competing workloads but does not increase the raw read access speed of the storage.