The ReadyNAS systems support both RAID levels. RAID 5 is an industry-standard RAID level whereas X-RAID is an Infrant patented RAID technology that simplifies and automates the RAID management process. X-RAID utilizes a one-volume technology with built-in volume expansion support, either by adding more disks or by replacing existing disk with larger capacity disks. For instance, you can start out with one disk, and add up to 3 more disks when you need more capacity or when you can afford them. Volume management is automatic. Add a 2nd disk, it becomes a mirror to the first, providing protection from a disk failure; add a 3rd, the capacity doubles; add a 4th, and your capacity triples . the expansion occurring while maintaining redundancy.
X-RAID also provides further expansion capability. At a future point in time, each disk can be replaced one by one, have it finish rebuilding, and after the last disk is replaced, your volume automatically expands utilizing the new capacity. This future-proof technology allows you to continuously expand as higher-capacity disks become available.
Performance-wise, X-RAID is optimized for larger sequential access request pattern, such as video streaming and editing. Performance overRAID 5 in large data transfer can be as much as 15-20% better.