Short for Synchronous Optical Network, a standard for connecting fiber-optic transmission systems. SONET was proposed by Bellcore in the middle 1980s and is now an ANSI standard.
SONET defines interface standards at the physical layer of the OSI seven-layer model. The standard defines a hierarchy of interface rates that allow data streams at different rates to be multiplexed. SONET establishes Optical Carrier (OC) levels from 51.8 Mbps (OC-1) to 9.95 Gbps (OC-192). Prior rate standards used by different countries specified rates that were not compatible for multiplexing. With the implementation of SONET, communication carriers throughout the world can interconnect their existing digital carrier and fiber optic systems.
The international equivalent of SONET, standardized by the ITU, is called SDH.
Short for Small Outline Package, it’s a low-profile rectangular surface-mount component package. Its chip is bonded to an inner land contact area (usually a lead frame). External terminals exit parallel to the seating plane on two opposite sides of the moulded, flat package. SOPs use gull wing formed leads, and is a surface mount package […]
Acronym for Spam and Open Relay Blocking System. SORBS was originally an anti-spam project where a daemon would check, in real time, all servers from which it received e-mail to determine if that e-mail was sent via various types of proxy and open-relay servers. SORBS has evolved into SORBS DNSbl (DNS-based blacklist) which now includes […]
- SO DIMM
Short for Small Outline DIMM, a small version of a DIMM used commonly in notebook computers. Whereas a full-size DIMM has 168 pins and supports 64-bit transfers, a SO DIMM has only 72 pins, which supports only 32-bit transfers, or 144 pins, which supports a full 64-bit transfer.
Short for stack page, a reserved space in Windows of 4K of memory that a 32-bit device driver uses to hold data and instructions as it works. The default setting in Windows sets one stack page for device drivers and two spare pages for temporary allocations. The spare pages are called MinSPs, short for minimum […]
Short for Scalable Processor Architecture, a RISC technology developed by Sun Microsystems. The term SPARC® itself is a trademark of SPARC International, an independent organization that licenses the term to Sun for its use. Sun’s workstations based on the SPARC include the SPARCstation, SPARCserver, Ultra1, Ultra2 and SPARCcluster.