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Term Description S (System) Reference Point An ISDN terminal or terminal adapter interface using four wires and alternate space inversion (ASI), sometimes referred to as pseudo-ternary, data coding. Up to eight devices can be connected in a multi-drop configuration to an S interface. S (System) Reference Point (ISDN) Interface between Terminal Adapters (TA) or terminal and Network termination SACD Super Audio Compact Disc SAR Segmentation, assembly and reassembly sublayer. It converts PDUs into appropriate lengths and formats them to fit the payload of an ATM cell format. At the destination end-station, the SAR extracts payloads from the cells and converts them back into PDUs to be ultimately used by applications. SAS Subscriber Authorization System.The SAS is responsible for generating the actual entitlement messages, following the specifications of the encryption standard used. Satellite Direct broadcast satellites that transmit TV programs can also provide Internet access. The satellite dish can deliver download speed of up to 350Kbps. Upload speeds are limited to ordinary analog modem speeds. Scaleable Font A font which can be scaled to any size, used as an alternative term for an outline font. Scan lines The parallel lines across a video screen, along which the scanning spot travels in painting the video information that makes up a monitor picture. NTSC systems use 525 scan lines to a screen; PAL systems use 625. Scanner Fundamentally, a scanner works similar to a digital camera. An image is scanned through a lens and onto either a CMOS sensor or a charge-coupled device (CCD), which is an array of light-sensitive diodes. The sensor chip is typically housed on a daughter card along with numerous A/D converters. The CCD and its circuitry create a digital reproduction of the image. It does this through a series of photodiodes-each containing red, green, and blue filters-that respond to different ranges of the optical spectrum. Once the picture is scanned the DSP and pixel co-processor produce a JPEG (joint photographic experts group) image that can be displayed on a screen. SCART Connector-standard used for TV/VCR devices. Also referred to as "Euro-connector". Scatternets (Bluetooth) Comprises of multiple interconnected Piconets schematic Design entry method where the logic is described graphically with symbols from a library. SCPC Abbreviation for Single Channel per Carrier. Scrambling Encryption of data to be transmitted for a specific service. scratch pad A temporary memory. Usually small and very fast. Used to hold intermediate data or information during complex or large computations. SCSI Small Computer Systems Interface SDLC Synchronous Data Link Control SDMI Secure Digital Music Initiative SDP Service Discovery Protocol SDSL Symmetric Digital Subscriber Line. Single-pair symmetric DSL. SECA Abbreviation for Societé Européene de Controle D'Access. SECAM format SEquential Couleur A Memoire (sequential color with memory), the French color TV system also adopted in Russia. See also NTSC, PAL. Secure MP3 MP3 files that are secure (encypted) and can be opened by a key. Segmented Routing Ability to tap off the routing lines at predefined intervals. SelectI/O Versatile I/O's that are used to select the appropriate I/O standard for the application. Eliminates the need for external level tranlsation chips, reducing the number of chips and board cost. SelectRAM+ SelectRAM+ refers to Distributed and Block RAM memories that are found in some Xilinx FPGA's. Sequential logic A flip-flop, synchronous RAM, or Latch. Service A sequence of programs under the control of a broadcaster which can be broadcasted as part of a schedule. Service Information Service Information data is a part of all the EPG data. Service Provider A company that collects the contents from a number of program/content providers and distributes the services to customers. Services Gateway Concept is being enabled by network operators or service providers (SP) such as telephone operators, ISP, cable TV operators, utilities. Session Arbitrating, establishing, and maintaining dialogs between applications. Session layer The Session Layer provides the means for two application layer entities to synchronize and manage their data exchange. It basically controls the communications between applications across a network .It sets up a communication channel between two Application - or - Presentation layer entities for the duration of the network transaction, manages the communication, and terminates the connections. Testing for out-of-sequence packets and handling two-way communication are also handled here. Set-top Box Set Top Boxes have revolutionized home entertainment by providing vibrant television images with crystal clear sound, along with e-mail, web surfing, customized information such as stock quotes, weather and traffic updates, on-line shopping, and video-on-demand right through a traditional television. Setup time Amount of time required for data to be stable prior to the clock for flip flops, memory or latches. Shannon Limit Refers to Shannon's noisy channel coding theorem. Which states that given a channel, one can associate a "channel capacity" such that there exist control codes that allow transmission across the channel at rates less than the channel capacity with an arbitrary small bit error rate. SI Service Information. Service Information data is a part of all the EPG data. SIF (Standard Interchange Format) Format for exchanging video images of 240 lines with 352 pixels each for NTSC, and 288 lines by 352 pixels for PAL and SECAM. At the nominal field rates of 60 and 50 fields/sec, the two formats have the same data rate. SIM Subscriber Identification Modules SIMM Acronym for Single Inline Memory Module. Type of memory package used to increase memory density on the printed circuit board. Simulation Software process of verifying the functionality of a design. Sixel Graphics A method of encoding bitmap graphics so that they may be reliably transmitted using Serial communication links. Skew The difference in arrival times of the same signal between two or more destinations. Slave (or Target) The Slave (or Target) is the target on the PCI bus. SLIC Subscriber Loop Interface Circuit. Electronic version of the two- to four-wire hybrid interface that supplies an analog signal from a line card to a subscriber's phone or network terminal equipment. It provides what is known as the BORSCHT functions in telephony (Battery Feed, Overvoltage Protection, Ringing, Signaling, Coding, Hybrid, and Test). Slice Two slices form a CLB within Virtex and Spartan-II families. Slot time The "slot time" is a key parameter for half-duplex Ethernet network operation. It is defined as 512 bit times for Ethernet networks operating at 10 and 100 Mb/s, and 4096 bit times for Gigabit Ethernet. In order for each transmitter to reliably detect collisions, the minimum transmission time for a complete frame must be at least one slot time, and the time required for collisions to propagate to all stations on the network must be less than one slot time. Smart Card A credit card size card containing updateable magnetic or chip memory, used for accessing encrypted TV services, e.g. when inserted in the decoder. Smart devices Any device that contains computing intelligence. Examples include PCs, set-top boxes, scanners, printers, web phones, etc. Smart-IP Xilinx IP that exhibits high performance, predictability, repeatability, and flexibility. SMS Subscriber Management System (other names: CMS, Customer Care and Billing System). The SMS is a part of a technical chain, referred to as the entitlement control chain. The SMS contains all customer relevant information and is responsible for keeping track of placed orders, credit limits, invoicing and payments, as well as the generation of reports and statistics. When an order is placed and accepted by the SMS, the system will support all administrative tasks regarding the customer, e.g. invoicing, payments and business reporting. SNMP Simple Network Management Protocol. SNMP is the network management protocol of choice for TCP/IP based Internets providing a means to monitor and set network configuration and runtime parameters. SNR Signal-To-Noise Ratio. A measure of the magnitude of a desired signal relative to the magnitude of an undesired signal or noise. Soft Font An alternative term for a downloaded font. Software Driver A generic term for a software utility such as a printer driver. Software Elements (HAVi) Software elements are basic mechanisms in HAVi to achieve interoperability. Each element provides a certain functionality. The Software Elements that are needed for interoperability between HAVi devices are the Messaging System, the Registry, the Event Manager, the Resource Manager, the Stream Manager and the DCM. SOHO Small Office, Home Office. SOHO Routers Synonomous with Home Servers and Residential Gateways. Communications processor that connects asynchronous devices to a LAN or WAN through network. SONET SONET stands for Synchronous Optical NETwork. The SONET format allows different types of formats to be transmitted on one line. SONET is a long term solution for a mid-span-meet between vendors. The other major advantage is that SONET allows ADDING and DROPING signals with a single multiplexer. Spatial resolution The number of points per unit length into which an image is divided. For example, 200 dots per inch (dpi). Spectral Compatibility Spectral usage of three services (POTS, UADSL & home phoneline networking) share the same phone line by operating at different frequencies. Spectrum A series of radiated energies arranged in order of wavelength. The radio spectrum extends from 20 kHz upward. Speed Throughput of a laser or ink jet printer measured in p.p.m or i.p.m. Splitter Filter to separate high-frequency ADSL and low-frequency POTS data. Requires costly installation in home. DSL G.Lite is splitterless, meaning it eliminates the need for an external splitter. Splitter / combiner A transmission component which divides or sums power between two or more ports. Spread spectrum (SS) A radio transmission technology that "spreads" the user information over a much wider bandwidth than otherwise required in order to gain benefits such as improved interference tolerance and unlicensed operation. This technique was developed by the military for use in reliable, secure, mission-critical wireless LAN communications systems. Spread-spectrum, imparts noise-like characteristics to an RF signal and is designed to trade off bandwidth efficiency for reliability, integrity, and security. In other words, more bandwidth is consumed than in the case of narrowband transmission, but the tradeoff produces a signal that is, in effect, louder and thus easier to detect, provided that the receiver knows the parameters of the spread-spectrum signal being broadcast. If a receiver is not tuned to the right frequency, a spread-spectrum signal looks like background noise. There are two types of spread spectrum radio: frequency hopping and direct sequence. This communications technique spreads a signal over a wide range of frequencies for transmission and then de-spreads it to the original data bandwidth at the receiver. SRAM Static Random Access Memory. SRAM consists of one flip-flop per bit of memory. Unlike DRAMs, static RAM retains its contents as long as power is applied. Because there is no need to refresh the contents of memory addresses which are read, SRAM is faster than DRAM, but it is more expensive and typically is available in much smaller sizes than DRAM because each bit occupies more space on the chip. SSL Secure Sockets Layer. A transport-level technology for authentication and data encryption between a Web server and a Web browser. SSTL Acronym for Stub Series Terminated Logic. It is a high-speed memory standard commonly used for chip to memory interface. Stability This determines whether a system exhibits oscillatory behavior or not. Standard Cell An ASIC technology that uses building blocks that are placed into standard size areas. Standby State (Bluetooth) Not connected to a Piconet, but occasionally monitors for inquiries from other devices, but not synchronized with any other devices. State Machine Design methodology that controls the output values of the logic based on the current state and the input values. StateCAD Software used to graphically design state machines. It is included in the Foundation ISE series software. Static Current Amount of current the device uses when powered on and inactive. Static State or DC State In this state, there are no switching signals within the device and the inputs and outputs are not transitioning. Static State or DC State It is the device used to change the voltage levels. Example: Device taking 220 Volts as Input and stepping down to 110 Volts as Output. STB Set-top Box Stream Manager (HAVi) One of the Software Elements that comprise the basic mechanisms in HAVi to achieve interoperability. Each element provides a certain functionality. The Software Elements that are needed for interoperability between HAVi devices are the Messaging System, the Registry, the Event Manager, the Resource Manager, the Stream Manager and the DCM. Streaming Audio Streaming refers to the playback of audio in real-time as it is transferred across the Internet The advantage of this approach is that the user does not have wait for the entire music file to be downloaded before hearing it. The tradeoff is that the music must be highly compressed in order to support the access rates that most users have, typically 28.8 to 56 Kbps This gives Net users instant gratification but relatively poor playback quality. In addition streaming audio players do not capture the content, so each time the clip is played it is transferred again. SVC Stored Value Card S-VHS or Super VHS A higher-quality extension of the VHS home videotape format, featuring higher luminance and the ability to produce better copies. S-video Type of video signal used in the Hi8 and S-VHS videotape formats. S-video transmits luminance and color portions separately, using multiple wires, thus avoiding the NTSC encoding process and its inevitable loss of picture quality. Also known as Y/C video. SWAP Shared Wireless Access Protocol. HomeRF Specification Switch A switch is a networking device that transfers data based on the destination addresses of the individual packets. It selects a path or circuit for sending a unit of data to its next destination. A switch is a simpler and faster mechanism than a router, which requires knowledge about the network and how to determine the route. Switches work like routers in that they divide the network into segments, and each segment operates without interference from local traffic to any of the other segments. Switching The operations involved in interconnecting circuits in order to establish communications. Symbol Width This is the number of bits per symbol. Synchronous Any operation that proceeds under control of a clock or timing mechanism. Synchronous Logic It is the amount of resources used in the device. The resources are: logic cells, IO cells, flip-flops and interconnect. Synthesis Process of converting HDL designs into FPGA specific features for Place And Route (PAR). System clock management Designing to minimize the clock skew or delay to different parts of the system, board or chip. System gates Methodology for measuring the amount of logic a device can implement. Originally created for ASIC market.   A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z