In telecommunications, a "carrier grade" or "carrier class" refers to a system, or a hardware or software component that is extremely reliable, well tested and proven in its capabilities. Carrier grade systems are tested and engineered to meet or exceed "five nines" high availability standards, and provide very fast fault recovery through redundancy (normally less than 50 milliseconds).
"Carrier grade" is not a standard or very clearly defined term but, rather, a set of features and qualities that make the product acceptable by a carrier. The feature set that enables the carrier to utilize the business with use of that equipment are: high quality and very good MTBF (some requirements are stated in TR-144 chapter 7.17), redundancy (if one part goes down, there is an alternative), easy and cost-efficient operations and maintenance (O&M), all of which are standardized as much as possible.
Safety engineering is an engineering discipline which assures that engineered systems provide acceptable levels of safety. It is strongly related to industrial engineering/systems engineering, and the subset system safety engineering. Safety engineering assures that a life-critical system behaves as needed, even when components fail.
An uninterruptible power supply (UPS) or uninterruptible power source is a type of continual power system that provides automated backup electric power to a load when the input power source or mains power fails. A UPS differs from a traditional auxiliary/emergency power system or standby generator in that it will provide near-instantaneous protection from input power interruptions by switching to energy stored in battery packs, supercapacitors or flywheels. The on-battery run-times of most UPSs are relatively short but sufficient to "buy time" for initiating a standby power source or properly shutting down the protected equipment. Almost all UPSs also contain integrated surge protection to shield the output appliances from voltage spikes.
Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that are glued together with adjacent layers, having both glued with each other at right angle. It is an engineered wood from the family of manufactured boards, which include plywood, medium-density fibreboard (MDF), oriented strand board (OSB), and particle board.
Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of both water clarity and water quality.
Educational assessment or educational evaluation is the systematic process of documenting and using empirical data on the knowledge, skill, attitudes, aptitude and beliefs to refine programs and improve student learning. Assessment data can be obtained by examining student work directly to assess the achievement of learning outcomes or it is based on data from which one can make inferences about learning. Assessment is often used interchangeably with test but is not limited to tests. Assessment can focus on the individual learner, the learning community, a course, an academic program, the institution, or the educational system as a whole. The word "assessment" came into use in an educational context after the Second World War.
Gas chromatography (GC) is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture. In preparative chromatography, GC can be used to prepare pure compounds from a mixture.
AM stereo is a term given to a series of mutually incompatible techniques for radio broadcasting stereo audio in the AM band in a manner that is compatible with standard AM receivers. There are two main classes of systems: independent sideband (ISB) systems, promoted principally by American broadcast engineer Leonard R. Kahn; and quadrature amplitude modulation (QAM) multiplexing systems.
Evolution-Data Optimized is a telecommunications standard for the wireless transmission of data through radio signals, typically for broadband Internet access. EV-DO is an evolution of the CDMA2000 (IS-2000) standard which supports high data rates and can be deployed alongside a wireless carrier's voice services. It uses advanced multiplexing techniques including code-division multiple access (CDMA) as well as time-division multiplexing (TDM) to maximize throughput. It is a part of the CDMA2000 family of standards and has been adopted by many mobile phone service providers around the world particularly those previously employing CDMA networks. It is also used on the Globalstar satellite phone network.
Radiation hardening is the process of making electronic components and circuits resistant to damage or malfunction caused by high levels of ionizing radiation, especially for environments in outer space, around nuclear reactors and particle accelerators, or during nuclear accidents or nuclear warfare.
Reliability engineering is a sub-discipline of systems engineering that emphasizes the ability of equipment to function without failure. Reliability describes the ability of a system or component to function under stated conditions for a specified period. Reliability is closely related to availability, which is typically described as the ability of a component or system to function at a specified moment or interval of time.
The Service Availability Forum is a consortium that develops, publishes, educates on and promotes open specifications for carrier-grade and mission-critical systems. Formed in 2001, it promotes development and deployment of commercial off-the-shelf (COTS) technology.
A paper bag is a bag made of paper, usually kraft paper. Paper bags can be made either with virgin or recycled fibres to meet customers' demands. Paper bags are commonly used as shopping carrier bags and for packaging of some consumer goods. They carry a wide range of products from groceries, glass bottles, clothing, books, toiletries, electronics and various other goods and can also function as means of transport in day-to-day activities.
Fault tolerance is the ability of a system to maintain proper operation despite failures or faults in one or more of its components. This capability is essential for high-availability, mission-critical, or even life-critical systems.
Avionics Full-Duplex Switched Ethernet (AFDX), also ARINC 664, is a data network, patented by international aircraft manufacturer Airbus, for safety-critical applications that utilizes dedicated bandwidth while providing deterministic quality of service (QoS). AFDX is a worldwide registered trademark by Airbus. The AFDX data network is based on Ethernet technology using commercial off-the-shelf (COTS) components. The AFDX data network is a specific implementation of ARINC Specification 664 Part 7, a profiled version of an IEEE 802.3 network per parts 1 & 2, which defines how commercial off-the-shelf networking components will be used for future generation Aircraft Data Networks (ADN). The six primary aspects of an AFDX data network include full duplex, redundancy, determinism, high speed performance, switched and profiled network.
High availability (HA) is a characteristic of a system that aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period.
An alarm monitoring center, central monitoring station, or alarm receiving center is a company that provides services to monitor burglar, fire, and residential alarm systems. The Central Monitoring Station may also provide watchman and supervisory services.
Communications servers are open, standards-based computing systems that operate as a carrier-grade common platform for a wide range of communications applications and allow equipment providers to add value at many levels of the system architecture.
OpenSAF is an open-source service-orchestration system for automating computer application deployment, scaling, and management. OpenSAF is consistent with, and expands upon, Service Availability Forum (SAF) and SCOPE Alliance standards.
Industrial process data validation and reconciliation, or more briefly, process data reconciliation (PDR), is a technology that uses process information and mathematical methods in order to automatically ensure data validation and reconciliation by correcting measurements in industrial processes. The use of PDR allows for extracting accurate and reliable information about the state of industry processes from raw measurement data and produces a single consistent set of data representing the most likely process operation.
Network functions virtualization (NFV) is a network architecture concept that leverages IT virtualization technologies to virtualize entire classes of network node functions into building blocks that may connect, or chain together, to create and deliver communication services.