Telecommunications — page 67 of 85

Telecommunications terms

6601. scanning line length In facsimile systems, the total length of a scanning line, equal to the spot speed divided by the scanning line frequency.
6602. scanning line period In facsimile systems, the time interval between (a) the instant at which the scanning spot probes or writes to a given spot on one scanning line, and (b)…
6603. scanning line rate Synonym scanning line frequency.
6604. scanning pitch The distance between the centers of consecutive scanning lines.
6605. scanning rate In facsimile and television systems, the rate of displacement of the scanning spot along the scanning line.
6606. scanning spot In facsimile systems, the area on the object, i.e., the original, covered instantaneously by the pickup system of the scanner.
6607. Scatter When refering to photons and light, scattering describes the phenomenon of a source absorbing, and then emanating light in all directions.
6608. Scattering The process in which a beam of light is diffused or deflected by collisions with particles suspended in the atmosphere.
6609. scattering center In the microstructure of a transmission medium, a site at which electromagnetic waves are scattered.
6610. scattering coefficient The factor that expresses the attenuation caused by scattering, e.g., of radiant or acoustic energy, during its passage through a medium.
6611. scattering cross section The area of an incident wavefront, at a reflecting surface or medium, such as an object in space, through which will pass radiant energy, that, if…
6612. scattering loss The part of the transmission (power) loss that results from scattering within a transmission medium or from roughness of a reflecting surface.
6613. scavenge To search, without authorization, through residual data to acquire sensitive information. [2382-pt.8]
6614. scavenging Searching through object residue to acquire data. [INFOSEC-99]
6615. SCC (1) Standing Consultative Commission (Treaty negotiation related term). (2) Space Control Center. 258
6616. Scene an area, object, or person external to the examining forensic laboratory facility, from which evidence is identified, documented, collected, and/or…
6617. scene cut Video imagery in which consecutive frames are highly uncorrelated.
6618. scene cut response In video systems, the perceived impairments associated with a scene cut.
6619. schematic A diagram, drawing, or sketch that details the elements of a system, such as the elements of an electrical circuit or the elements of a logic diagram for…
6620. scintillation In electromagnetic wave propagation, a small random fluctuation of the received field strength about its mean value.
6621. scrambler A device that transposes or inverts signals or otherwise encodes a message at the transmitter to make the message unintelligible at a receiver not…
6622. scratch pad store (SPS) Temporary key storage in crypto-equipment. [INFOSEC-99]
6623. scream Synonym bang.
6624. screen A screen is a set of criteria against which you measure stocks or other investments to find those that meet your criteria.
6625. screen capture In computers, the process or act by which the data currently displayed on a monitor, usually representing a single frame of information, are stored or…
6626. screened subnetwork A subnetwork that permits access from both untrusted external networks and from trusted internal networks, but does not permit traffic flow between the…
6627. screened-host gateway Synonym bastion host.
6628. screening router A network router capable of discriminating network-based traffic on the protocol type and the value of the protocol fields within the packet. [2382-pt.35]
6629. script A text "file" that is a program intended to be executed directly rather than compiled to another form of file before execution.
6630. scripting language A programming language designed specifically for Web site programming. Examples include JScript and Microsoft Visual Basic Scripting Edition (VBScript).
6631. scroll In a display device, to move the display window of the screen vertically to view the contents of a stored document.
6632. scroll-mode terminal A terminal in which the data are displayed (or pass by) a line at a time.
6633. SCSI Small Computer Systems Interface.
6634. SDARS See satellite digital audio radio service.
6635. SDLC Synchronous Data Link Control ( TelComm /Computer term).
6636. Seal To mark a document with a seal; to authenticate or make binding by affixing a seal. Court seal, corporate seal.
6637. Search Engine A program that enables search for keywords or phrases, such as on web pages throughout the World Wide Web.
6638. search robot See bot, droid.
6639. search time In data processing systems, the time interval required to locate a particular data element, record, or file in a storage device.
6640. SECAM Acronym for système electronique couleur avec memoire. A television signal standard (625 lines, 50 Hz, 220 V primary power) used in France, eastern…
6641. second (s) In the International System of Units (SI), the time interval equal to 9,192,631,770 periods of the radiation corresponding to the transition between the…
6642. second dialtone Dialtone presented to the call originator after an access code has been dialed for access to a second, outside, telecommunications system or service. 2.
6643. second window Of silica-based optical fibers, the transmission window at approximately 1.3 m.
6644. secondary channel In a system in which two channels share a common interface, a channel that has a lower data signaling rate (DSR) capacity than the primary channel.
6645. secondary emission Particles or radiation, such as photons, Compton recoil electrons, delta rays, secondary cosmic rays, and secondary electrons, that are produced by the…
6646. secondary frequency standard A frequency standard that does not have inherent accuracy, and therefore must be calibrated against a primary frequency standard.
6647. secondary radar A radiodetermination system based on the comparison of reference signals with radio signals retransmitted from the position to be determined.
6648. secondary radiation See secondary emission.
6649. secondary service area [T]he service area of a broadcast station served by the skywave and not subject to objectionable interference and in which the signal is subject to…
6650. Secondary Station A station that has been selected to receive a transmission from the primary station.
6651. secondary surveillance radar Synonym secondary radar.
6652. secondary time standard A time standard that requires periodic calibration against a primary time standard.
6653. SECORD Acronym for secure voice cord board. A desk-mounted patch panel that provides the capability for controlling (a) sixteen 50-kb/s wideband or sixteen…
6654. Secret Key A cryptographic key that is used with a secret key (symmetric) cryptographic algorithm, that is uniquely associated with one or more entities and is not…
6655. secret key encryption Any encryption process that (a) depends on only one encryption key, known only to message senders and receivers, and (b) is used to both encode and decode…
6656. SECTEL Acronym for secure telephone. See STU.
6657. section An area equal to 640 acres or 1 square mile.
6658. section boundary The boundary that separates a network section from the adjacent circuit section, or separates an access circuit section from the adjacent DTE (data…
6659. Sector A sector is a segment of the economy that shares distinctive characteristics, such as telecommunications or energy.
6660. sector alignment A copy-protection technique for copy protection that determines whether a diskette is an unauthorized copy by checking whether sectors are positioned…
6661. sectoring In magnetic or optical disk storage media, the division of tracks into a specified number of segments, for the purpose of organizing the data stored…
6662. secure communications Telecommunications deriving security through use of type 1 products and/or protected distribution systems. [INFOSEC-99]
6663. secure hash standard [The] specification for a secure hash algorithm that can generate a condensed message representation called a message digest. [INFOSEC-99]
6664. secure operating system Resident software controlling hardware and other software functions in an information system (IS) to provide a level of protection or security appropriate…
6665. secure state [The] condition in which no subject can access any object in an unauthorized manner. [INFOSEC-99]
6666. secure subsystem [A] Subsystem containing its own implementation of the reference monitor concept for those resources it controls.
6667. secure telephone unit See STU.
6668. secure transmission In transmission security, see secure communications. 2. In spread-spectrum systems, the transmission of binary coded sequences that represent information…
6669. secure voice cord board See SECORD.
6670. Security The term "security" covers a broad variety of financial instruments, including stock, promissory notes, bonds, debentures, limited partnership interests…
6671. security administration left
6672. security administrator 1. An authority (a person or group of people) responsible for implementing the security policy for a security domain [ECMATR46]. 2.
6673. security alarm A security-related event that has been identified by a security policy as a potential breach of security. [T1.233-1993]
6674. Security Architecture The portion of the baseline SDS architecture that is responsible for preserving the confidentiality, integrity, and assured service of any of the…
6675. Security Attribute A security-related quality of an object. Security attributes may be represented as hierarchical levels, bits in a bit map, or numbers.
6676. security attributes A set of properties associated with a principal. Security attributes can be associated with a principal by an authentication protocol or by a J2EE product…
6677. security audit 1. Of data processing operations, an independent review and examination of system records and activities to (a) determine the adequacy of system controls…
6678. security audit message left
6679. security audit record left
6680. security audit trail left
6681. security auditor left
6682. Security Category The characterization of information or an information system based on an assessment of the potential impact that a loss of confidentiality, integrity, or…
6683. security certificate A set of security relevant data which is protected by integrity and data origin authentication from an issuing security authority, and includes an…
6684. security class The combination of classification, categories and caveats associated with an object [CESG].
6685. security classification A classification placed on records limiting their accessibility to those having specific authority to retrieve or use them See also restricted access.
6686. security clearance 1. The formal authorization by the Departmental Security Officer for an individual to have access to classified information, following appropriate vetting…
6687. Security Domain A set of subjects, their information objects, and a common security policy.
6688. security enforcing justify
6689. security event manager left
6690. security exchange The mechanism for conveying, or the conveyance of, security-related information between two entities. [After X9.41]
6691. security facility A set of logically associated security functions as used in the security framework [ECMATR46].
6692. security facility interaction The invocation of a function a security facility by another security facility [ECMATR46].
6693. security fault analysis [An] Assessment, usually performed on information system (IS) hardware, to determine the security properties of a device when hardware fault is…
6694. security fault notification Report prepared by a CLEF and initially distributed to the Certification Body (CB).
6695. security filter In communications security, the hardware, firmware, or software used to prevent access to specified data by unauthorized persons or systems, such as by…
6696. security flaw [An] Error of commission or omission in an information system (IS) that may allow protection mechanisms to be bypassed. [INFOSEC-99]
6697. security function A discrete aspect of the performance of a system by which it enforces security automatically on behalf of the System Manager and /or system users [CESG].
6698. security interaction policy Common aspects of security policies necessary in order for interactions to take place between domains [10181-1]..
6699. security kernel 1. In computer and communications security , the central part of a computer or communications system hardware, firmware, and software that implements the…
6700. Security Label Explicit or implicit marking of a data structure or output media associated with an information system representing the FIPS 199 security category, or…