Areca ARC-1130 User Manual

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speed, switched architecture. Each PCI Express link is a serial commu-

nications channel made up of two differential wire pairs that provide 

2.5 Gbits/sec in each direction. Up to 32 channels may be combined, 

creating a parallel interface of independently controlled serial links.

(PCI extended) an enhanced PCI bus technology is backward compat-

ible with existing PCI cards. PCI and PCI-X slots are physically the 

same. PCI cards run in PCI-X slots, and PCI-X cards run in PCI slots at 

the slower PCI rates. First introduced in 1999, PCI-X offered increased 

speed over PCI and has steadily increased to more than 30 times that 

of the original PCI bus.  

(Redundant Array of Independent Disks) a disk subsystem that is used 

to increase performance or provide fault tolerance. RAID can also be 

set up to provide both functions at the same time. RAID is a set of 

two or more ordinary hard disks and a specialized disk controller that 

contains the RAID functionality. RAID has been developed initially for 

servers and stand-alone disk storage systems. RAID is important espe-

cially when rebuilding data after a disk failure.

When a RAID array enters into a degraded mode, it is advisable to 

rebuild the array and return it to its original configuration (in terms of 

the number and state of working disks) to ensure against operation in 

degraded mode.

The evolution of the ATA (IDE) interface that changes the physical 

architecture from parallel to serial and from master-slave to point-

to-point. Unlike parallel ATA interfaces that connect two drives; one 

configured as master, the other as slave, each Serial ATA drive is con-

nected to its own interface. At initial introduction, Serial ATA (SATA) 

increases the transfer rate to 150 MB/sec (1.5Gb/s) and SATA2 to 300 

MB/sec.