Tomcat i7230A S5160 

                                                                     Appendix I: Glossary 

RAID (Redundant Array of Independent Disks): a way for the same data to be stored in 

different places on many hard drives. By using this method, the data is stored redundantly, 

also the multiple hard drives will appear as a single drive to the operating system. RAID level 0 

is known as striping, where data is striped (or overlapped) across multiple hard drives, but 

offers no fault tolerance. RAID level 1 is known as mirroring, which stores the data within at 

least two hard drives, but does not stripe. RAID level 1 also allows for faster access time and 

fault tolerance, since either hard drive can be read at the same time. RAID level 0+1 is both 

striping and mirroring, providing fault tolerance, striping, and faster access all at the same 

time. 

RAIDIOS: stands for RAID I/O Steering, a type of RAID technology from Intel. RAIDIOS is a 

specification used to enable an embedded I/O controller, embedded on the motherboard, to be 

used as just an I/O controller or to be the I/O component of a hardware RAID subsystem. The 

RAIDIOS circuit allows an I/O Processor (either embedded on the motherboard or on an add 

in card) to configure the I/O controller and service the I/O controller's interrupts. The I/O 

controller and the I/O Processor together are two of the primary components of a hardware 

RAID subsystem.  

RAM (Random Access Memory): technically refers to a type of memory where any byte can 

be accessed without touching the adjacent data, is often used to refer to the system's main 

memory. This memory is available to any program running on the computer. 

ROM (Read Only Memory): a storage chip which contains the BIOS; the basic instructions 

required to boot the computer and start up the operating system. 

SATA (Serial ATA): is an evolutionary replacement for the Parallel ATA physical storage 

interface. Serial ATA is a drop in solution in that it is compatible with today's software and 

operating systems.  It will provide for systems which are easier to design, with cables that are 

simpler to route and install, smaller cable connectors, and lower voltage requirements. 

SDRAM (Synchronous Dynamic RAM): called as such because it can keep two sets of 

memory addresses open simultaneously. By transferring data alternately from one set of 

addresses and then the other, SDRAM cuts down on the delays associated with non 

synchronous RAM, which must close one address bank before opening the next. 

Serial port: called as such because it transmits the eight bits of a byte of data along one wire, 

and receives data on another single wire (that is, the data is transmitted in serial form, one bit 

after another). 

SCSI Interrupt Steering Logic (SISL): Architecture that allows a RAID controller, such as 

AcceleRAID 150, 200 or 250, to implement RAID on a system board embedded SCSI bus or a 

set of SCSI busses.  SISL: SCSI Interrupt Steering Logic ( LSI )  (only on LSI SCSI boards) 

SIMM (Single In line Memory Module): formally the most common form of RAM for 

motherboards. They must be installed in pairs, and do not have the carrying capacity or the 

speed of DIMM modules. 

Sleep/Suspend mode: in this mode, all devices except the CPU shut down. 

SRAM (Static RAM): unlike DRAM, this type of RAM does not need to be refreshed in order 

to prevent data loss. Thus, it is faster and more expensive. 

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