(When you get an IPSAN, you can roughly judge which model the IPSAN is based on the shape of the IPSAN. There are three types of IPSAN: A20, A10, A9, of which A20 has the best performance, followed by A10, and finally A9. The IPSAN is named according to the number of hard disks that can be plugged into the IPSAN. If the IPSAN of the model A20 can plug in a total of 16 hard disks, the IPSAN is named A2016.)