RAID 1 has the advantage of providing improved read speeds and additional protection of the hard disks if the controller or the management software enables simultaneous access to more than one storage medium. In case of the former, this is made possible by parallel access to different sectors, in the latter case by comparing the data.
Its greatest strength – complete redundancy – is also its weakness. Since every hard disk in the network must store the same data, lots of potential storage capacity is automatically lost. Conversely, this means that RAID 1 storage is at least twice as expensive (when two hard drives are combined) as individual data carriers with the same storage capacity. Compared to other RAID levels that generate redundancy with the help of parity, the high-cost factor of RAID 1 is a disadvantage.