Synchronization protocols
Protocols that allow users to view, modify, and transfer or update data between a cell phone or personal digital assistant (PDA) and a PC or vice versa. The two most common synchronization protocols are Microsoft’s ActiveSync and Palm’s HotSync.
Synchronous communication
The transmission of data at very high speeds using circuits in which the transfer of data is synchronized by electronic clock signals. Synchronous communication is used within the computer and in high-speed mainframe computer networks.
Synchronous optical network (SONET)
A physical layer standard that provides an international specification for high-speed digital transmission via optical fiber. At the source interface, signals are converted from electrical to optical form. They are then converted back to electrical form at the destination interface.
Synchronous transmission
The serial transmission of a bit stream in which each bit occurs at a fixed time interval and the entire stream is preceded by a specific combination of bits that initiate the timing.
Syntax error
An error resulting from the expression of a command in a way that violates a program’s syntax rules. Syntax rules specify precisely how a command, statement, or instruction must be given to the computer so that it can recognize and process the instruction correctly.
Syslog
A protocol that specifies a general log entry format and a log entry transport mechanism. Log facility is the message type for a syslog message.
System
A discrete set of information resources organized for the collection, processing, maintenance, use, sharing, dissemination, or disposition of information. A generic term used for briefness to mean either a major/minor application (MA) or a general support system (GSS).
System administrator
A person who manages a multiuser computer system, including its operating system and applications, and whose responsibilities are similar to that of a network administrator. A system administrator would perform systems programmer activities with regard to the operating system and network control programs.
System availability
(1) A timely, reliable access to data, system, and information services for authorized users. (2) A measure of the amount of time that the system is actually capable of accepting and performing a user’s work. (3) The availability of communication ports and the amount or quantity of service received in a given period. (4) Can be viewed as a component of system reliability. The availability of a computer system can be expressed as a percentage in several ways, as follows:
Availability = (Uptime)/(Uptime + Downtime) × 100
Availability = (Available time/Scheduled time) × 100
Availability = [(MTTF)/(MTTF + MTTR)] × 100
Availability = (MTTF/MTBF) × 100
System confidentiality
Assurance that information is not disclosed to unauthorized individuals, processes, or devices.
System development life cycle (SDLC)
A systematic process for planning, analyzing, designing, developing, implementing, operating, and maintaining a computer-based application system. The scope of activities associated with a system, encompassing the system’s initiation, development and acquisition, implementation, operation and maintenance, and ultimately its disposal that instigates another system initiation.
System development methodologies
Methodologies developed through software engineering to manage the complexity of system development. Development methodologies include software engineering aids and high-level design analysis tools.
System high
The highest security level supported by a system at a particular time or in a particular environment (e.g., military/weapon systems, aircraft systems, and nuclear systems).
System integrity
(1) Quality of a system or product reflecting the logical correctness and reliability of the operating system; verification that the original contents of information have not been altered or corrupted. (2) The quality that a system has when it performs its intended function in an unimpaired manner, free from unauthorized manipulation of the system, whether intentional or accidental.
System integrity exposure
A condition that exists when there is a potential of one or more programs that can bypass the installation’s control and (a) circumvent or disable store or fetch protection, (b) access a protected resource, and (c) obtain control in authorized (supervisor) state. This condition can lead to compromise of systems protection mechanisms and data integrity.
System inventory
Organizations require a system inventory in place. All systems in the inventory should be categorized as a first step in support of the security planning activity and eventually in the assessment of the security controls implemented on the system.
System life
A projection of the time period that begins with the installation of a system resource (e.g., software or hardware) and ends when the organization’s need for that resource has terminated.
System low
The lowest security level supported by a computer system at a particular time or in a particular environment.
System manager
The IT manager who is responsible for the operation of a computer system.
System parameter
A factor or property whose value determines a characteristic or behavior of the system.
System reliability
The terms system reliability and system availability are closely related and often used (although incorrectly) synonymously. For example, a system that fails frequently but is restarted quickly has high availability even though its reliability is low. To distinguish between the two, reliability can be thought of as the quality of service and availability as the quantity of service. System reliability is measured in terms of downtime hours in a given period of time.
System resilience
The ability of a computer system to continue to function correctly despite the existence of a fault or faults in one or more of its component parts.
System security plan
Formal document that provides an overview of the security requirements for the information system and describes the security controls in place or planned for meeting those requirements.
System-specific control
A security control for an information system that has not been designated as a common security control or the portion of a hybrid control that is to be implemented within an information system.
Systems engineering
The systematic application of technical and managerial processes and concepts to transform an operational need into an efficient, cost-effective system using an iterative approach to define, analyze, design, build, test, and evaluate the system.
Systems software
(1) A major category of programs used to control the computer and process other programs, such as secure operating systems, communications control programs, and database managers. (2) Contrasts with applications software, which comprises the data entry, update, query, and report programs that process an organization’s data. (3) The operating system and accompanying utility programs that enable a user to control, configure, and maintain the computer system, software, and data.
System transparency
Transparency is the ability to simplify the task of developing management applications, hiding distribution details. There are different aspects of transparency such as access failure, location, migration replication, and transaction. Transparency means the network components or segments cannot be seen by insiders and outsiders and that actions of one user group cannot be observed by other user groups. It is achieved through process isolation and hardware segmentation concepts.