The amount of time between a packet of data being sent to it being received between two devices on a network.

This is somewhere between compute and networking really (and in truth they live in the EC2 section of the AWS console), but I stretched the limits of what I could call a “compute service” already, so they’re going here instead.

Referring to the ability to redistribute load (read/write requests) to an alternate path between server and storage device, load balancing helps to maintain high-performance networking. 

A logical unit is a conceptual division (a subunit) of a storage disk or a set of disks. Logical units can directly correspond to a volume drive (for example, C: can be a logical unit). Each logical unit has an address, known as the logical unit number (LUN), which allows it to be uniquely identified. 

A method to restrict server access to storage not specifically allocated to that server. LUN masking is similar to zoning but is implemented in the storage array, not the switch.