Identify and describe one primary functional component of a software application

Circuit-Switched Networks

Jean Walrand, Pravin Varaiya, in High-Performance Communication Networks (Second Edition), 2000

5.6.3 Functional Components

We briefly describe the functional components, the atomic actions on network resources, in five types of network operations.

Control of Processing

The functional components for control of processing are of two types: to provide instructions when the SSP asks the SCP to take control of the call processing and to effect the release of control when the SCP returns the control to the SSP after servicing the request.

Connection Request

A connection request involves the following functional components: creating a leg between an SSP and another network element, joining a leg to an ongoing call, splitting a leg from an ongoing call, and freeing a leg to release the resource.

User Interaction Request

Two types of functional components are invoked in user interactions: sending information such as a prerecorded announcement to a call participant and receiving specific information such as dialed digits from a call participant.

Network Resource Status Request

Network resource status requests are used by the SLP in processing some call control. Monitoring is a functional component that instructs the SSP for notification of a particular event on a specified leg, such as on-hook, flash-hook, and off-hook.

Network Information Revision Request

Network information revision requests enable the SLP to change the data stored in the SSP tables.

In summary, INA is a culmination of a long development in which network element functions or operations are separated from the control of those functions. This separation permits the creation of new services as programmable sequences of functional components. Sophisticated customers can program these sequences by themselves. A very important example is 800 number services. Companies, such as credit card and direct order companies that provide direct customer services over the 800 number phone, can route customer calls to different parts of the country or to different operators depending on the time of day, the subscriber's location, and other information provided by the subscriber via the telephone keypad.

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Formulating the Functional Architecture

Richard F. Schmidt, in Software Engineering, 2013

10.2.1 Functional component

A functional component represents a complex task the software product must perform. A functional component is activated when control is transferred to the component for execution. Every function transforms one or more data items, in the form of an input or global or local variables, into an output data item or processed variable. Functional complexity is apparent when any of the following conditions exists:

A function involves several data transformation actions and at least one action has no clear, uncomplicated solution.

A function involves distinguishable conditional responses.

A function involves multiple interfaces with other functions or external systems, users, or other software applications, such as databases.

Functional complexity compels the solution to be further decomposed into less complex functional components. Decomposition requires that a functional component be broken down into two or more subfunctions. The designation of a function as a component indicates that it involves a lower level of functional detail to unambiguously express the manner by which the data processing or transformation is performed. Several layers of decomposition may be necessary to establish a noncomplex solution.

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Genesis of SDN

Paul Göransson, ... Timothy Culver, in Software Defined Networks (Second Edition), 2017

3.2.5 ForCES: Separation of Forwarding and Control Planes

The Forwarding and Control Element Separation(ForCES) [19] work produced in the IETF began around 2003. ForCES was one of the original proposals recommending the decoupling of forwarding and control planes as well as a standard interface for communication between them. The general idea of ForCES was to provide simple hardware-based forwarding entities at the foundation of a network device, and software-based control elements above. These simple hardware forwarders were constructed using cell switching or tag switching technology. The software-based control had responsibility for the broader tasks often involving coordination between multiple network devices (e.g., Border Gateway Protocol routing updates).

The functional components of ForCES are as follows:

Forwarding Element: The Forwarding Element(FE) would be typically implemented in hardware and located in the network. The FE is responsible for enforcement of the forwarding and filtering rules that it receives from the controller.

Control Element: The Control Element(CE) is concerned with the coordination between the individual devices in the network, and for communication of forwarding and routing information to the FEs below.

Network Element: The Network Element(NE) is the actual network device which consists of one or more FEs and one or more CEs.

ForCES Protocol: The ForCES protocol is used to communicate information back and forth between FEs and CEs.

ForCES proposes the separation of the forwarding plane from the control plane, and it suggests two different embodiments of this architecture. In one of these embodiments, both the forwarding and control elements are located within the networking device. The other embodiment speculates that it would be possible to actually move the control element(s) off of the device and to locate them on an entirely different system. Although the suggestion of a separate controller thus exists in ForCES, the emphasis is on the communication between CE and FE over a switch backplane, as shown in Fig. 3.4.

Identify and describe one primary functional component of a software application

Fig. 3.4. ForCES design.

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Cognitive Radio Architecture

Joseph MitolaIII, in Cognitive Radio Technology (Second Edition), 2009

14.2.2 Design Rules Include Functional Component Interfaces

The six functional components (see Table 14.2(a) and (b)) imply associated functional interfaces. In architecture, design rules may constrain the quantities and types of components as well as the interfaces among those components. This section addresses the interfaces among the functional components.

Table 14.2(a). CR N-Squared Diagram

From/ToUser SPEnvironmentSys-AppsSDRCognitionEffectors
User SP 1 7 13 PAa 19 25 PAb 31
Environment 2 8 14 SAa 20 26 PAb 32
Sys-Apps 3 9 15 SCMa 21 SDa 27 PDCa,b 33 PEMa
SDR 4 10 16 PDa 22 SD 28 PCb 34 SD
Cognition 5 PECb 11 PECb 17 PCa,b 23 PAEb 29 SCb 35 PEb
Effectors 6 SC 12 18a 24 30 PCDb 36

Note: This matrix characterizes internal interfaces between functional processes. Interface notes 1–36 are explained in Table 14.2(b).

P = primary; A = afferent; E = efferent; C = control; M = multimedia; D = data; S = secondary; others not designated P or S are ancillary.

aInformation services API. bCAPI.

Table 14.2(b). Explanations of Interface Notes for Functional Processes Shown in Table 14.2(a)

Note No.Process InterfaceExplanation
1 User SP–User SP Cross-media correlation interfaces (video-acoustic, haptic-speech, etc.) to limit search and reduce uncertainty (e.g., if video indicates user is not talking, acoustics may be ignored or processed less aggressively for command inputs than if user is speaking).
2 Environment–User SP Environment sensors parameterize user sensor-perception. Temperature below freezing may limit video.
3 Sys-Apps–User SP Sys-apps may focus scene perception by identifying entities, range, expected sounds for video, audio, and spatial perception processing.
4 SDR–User SP SDR applications may provide expectations of user input to the perception system to improve probability of detection and correct classification of perceived inputs.
5 Cognition–User SP This is the primary control efferent path from cognition to the control of the user SP subsystem, controlling speech recognition, acoustic signal processing, video processing, and related SP. Plans from cognition may set expectations for user scene perception, improving perception.
6 Effectors–User SP Effectors may supply a replica of the effect to user perception so that self-generated effects (e.g., synthesized speech) may be accurately attributed to the <Self/>, validated as having been expressed, and/or cancelled from the scene perception to limit search.
7 User SP–Environment Perception of rain, buildings, indoor/outdoor can set GPS integration parameters.
8 Environment–Environment Environment sensors would consist of location sensing such as GPS or Galileo; ambient temperature; light level to detect inside versus outside locations; possibly smell sensors to detect spoiled food, fire, etc. There seems to be little benefit in enabling interfaces among these elements directly.
9 Sys-Apps–Environment Data from the sys-apps to environment sensors would also be minimal.
10 SDR–Environment Data from the SDR personalities to the environment sensors would be minimal.
11 Cognition–Environment (primary control path) Data from the cognition system to the environment sensors control those sensors, turning them on and off, setting control parameters, and establishing internal paths from the environment sensors.
12 Effectors–Environment Data from effectors directly to environment sensors would be minimal.
13 UserSP–Sys-Apps Data from the user SP system to sys-apps is a primary afferent path for multimedia streams and entity states that effect information services implemented as sys-apps. Speech, images, and video to be transmitted move along this path for delivery by the relevant sys-apps or information service to the relevant wired or SDR communications path. Sys-apps overcomes the limitations of individual paths by maintaining continuity of conversations, data integrity, and application coherence (e.g., for multimedia games). Whereas the cognition function sets up, tears down, and orchestrates the sys-apps, the primary API between the user scene and the information service consists of this interface and its companions—the environment afferent path, the effector efferent path, and the SDR afferent and efferent paths.
14 Environment–Sys-Apps Data on this path assist sys-apps in providing location awareness to services.
15 Sys-Apps–Sys-Apps Different information services interoperate by passing control information through the cognition interfaces and by passing domain multimedia flows through this interface. The cognition system sets up and tears down these interfaces.
16 SDR–Sys-Apps This is the primary afferent path from external communications to the AACR. It includes control and multimedia information flows for all the information services. Following the SDR Forum's SCA, this path embraces wired as well as wireless interfaces.
17 Cognition–Sys-Apps Through this path, the AACR <Self/> exerts control over the information services provided to the <User/>.
18 Effectors–Sys-Apps Effectors may provide incidental feedback to information services through this afferent path, but the use of this path is deprecated. Information services are supposed to control and obtain feedback through the mediation of the cognition subsystem.
19 User SP–SDR Although the SP system may send data directly to the SDR subsystem (e.g., to satisfy security rules that user biometrics be provided directly to the wireless security subsystem), the use of this path is deprecated. Perception subsystem information is supposed to be interpreted by the cognition system so that accurate information, not raw data, can be conveyed to other subsystems.
20 Environment–SDR Environment sensors such as GPS historically have accessed SDR waveforms directly (e.g., providing timing data for air-interface signal generation). The cognition system may establish such paths in cases where cognition provides little or no value added, such as providing a precise timing reference from GPS to an SDR waveform. The use of this path is deprecated because all of the environment sensors, including GPS, are unreliable. Cognition has the capability to “deglitch” GPS (e.g., recognize from video that the <Self/> is in an urban canyon and therefore not allow GPS to report directly, but report to the GPS subscribers, on behalf of GPS, location estimates based perhaps on landmark correlation, dead reckoning, etc.).
21 Sys-apps–SDR This is the primary efferent path from information services to SDR through the services API.
22 SDR–SDR The linking of different wireless services directly to each other is deprecated. If an incoming voice service needs to be connected to an outgoing voice service, there should be a bridging service in sys-apps through which the SDR waveforms communicate with each other. That service should be set up and taken down by the cognition system.
23 Cognition–SDR This is the primary control interface, replacing the control interface of the SDR SCA and the OMG SRA.
24 Effectors–SDR Effectors such as speech synthesis and displays should not need to provide state information directly to SDR waveforms, but if needed, the cognition function should set up and tear down these interfaces.
25 User SP–Cognition This is the primary afferent flow for the results from acoustics, speech, images, video, video flow, and other sensor-perception subsystems. The primary results passed across this interface should be the specific states of <Entities/> in the scene, which would include scene characteristics such as the recognition of landmarks, known vehicles, furniture, and the like. In other words, this is the interface by which the presence of <Entities/> in the local scene is established and their characteristics are made known to the cognition system.
26 Environment–Cognition This is the primary afferent flow for environment sensors.
27 Sys-Apps–Cognition This is the interface through which information services request services and receive support from the AACR platform. This is also the control interface by which cognition sets up, monitors, and tears down information services.
28 SDR–Cognition This is the primary afferent interface by which the state of waveforms, including a distinguished RF-sensor waveform, is made known to the cognition system. The cognition system can establish primary and backup waveforms for information services, enabling the services to select paths in real time for low-latency services. Those paths are set up and monitored for quality and validity (e.g., obeying XG rules) by the cognition system, however.
29 Cognition–Cognition The cognition system as defined in this six-component architecture entails the following: (1) orienting to information from RF sensors in the SDR subsystem and from scene sensors in the user SP and environment sensors; (2) planning; (3) making decisions; and (4) initiating actions, including the control over all of the cognition resources of the <Self/>. The <User/> may directly control any of the elements of the systems via paths through the cognition system that enable it to monitor what the user is doing in order to learn from a user's direct actions, such as manually tuning in the user's favorite radio station when the <Self/> either failed to do so properly or was not asked.
30 Effectors–Cognition This is the primary afferent flow for status information from the effector subsystem, including speech synthesis, displays, and the like.
31 User SP–Effectors In general, the user SP system should not interface directly to the effectors, but should be routed through the cognition system for observation.
32 Environment–Effectors The environment system should not interface directly to the effectors. This path is deprecated.
33 Sys-Apps–Effectors Sys-apps may display streams, generate speech, and otherwise directly control any effectors once the paths and constraints have been established by the cognition subsystem.
34 SDR–Effectors This path may be used if the cognition system establishes a path, such as from an SDR's voice track to a speaker. Generally, however, the SDR should provide streams to the information services of the sys-apps. This path may be necessary for legacy compatibility during the migration from SDR through AACR to iCR, but it is deprecated.
35 Cognition–Effectors This is the primary efferent path for the control of effectors. Information services provide the streams to the effectors, but cognition sets them up, establishes paths, and monitors the information flows for support to the user's <Need/> or intent.
36 Effectors–Effectors These paths are deprecated, but may be needed for legacy compatibility.

The CR N-squared diagram of Table 14.2(a) characterizes CR interfaces. These constitute an initial set of CR APIs, augmenting the established SDR APIs. This enables basic CRs to accommodate the dynamic spectrum behavior of the Defense Advanced Research Projects Agency (DARPA) NeXt-Generation (XG), and Wireless Network after Next (WNaN) radio communication programs.

In other ways, these APIs supersede the existing SDR APIs. In particular, the SDR user interface (GUI) becomes the user sensory and effector API. User sensory APIs include acoustics, voice, and video, and the effector APIs include speech synthesis to give the CR <Self/> its own voice. In addition, wireless applications are growing rapidly. Voice and short-message service provide an ability to exchange images and video clips with semantic tags among wireless users. The distinctions between cell phone, personal digital assistant (PDA), and game box continue to disappear.

These interface changes enable the CR to sense the situation, to interact with the user, and to access radio networks on behalf of the user according to its situational assessment. This matrix characterizes internal interfaces between functional processes. Interface notes 1 to 36 are explained in Table 14.2(b).

The preceding information flows, aggregated into an initial set of CR APIs, define an information services API (ISAPI) by which an information service accesses the other five components (interfaces 13–18, 21, 27, and 33 in Table 14.2(a)). They would also define a CAPI by which the cognition system obtains status and exerts control over the rest of the system (interfaces 5, 11, 17, 23, 25–30, and 35 in Table 14.2(a)). Although the constituent interfaces of these APIs are suggested in this table, it would be premature to define these APIs without first developing detailed information flows and interdependencies. We will define and analyze these APIs in this chapter. It would also be premature to develop such APIs without a clear idea of the kinds of RF and user domain knowledge and performance expected of the CR architecture over time. These aspects are developed in the balance of this chapter, enabling one to draw some conclusions about these APIs in the final part of this chapter.

A fully defined set of interfaces and APIs would be circumscribed in RXML.

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Protecting Virtual Infrastructure

Edward G. Amoroso, in Computer and Information Security Handbook (Third Edition), 2017

3 Hypervisor Security

The most important functional component in any virtual infrastructure is the hypervisor. Ensuring that the underlying hypervisor is sufficiently secure is an important first step toward overall virtualization security. The US National Institute for Standards and Technology (NIST) published a guide for securing the hypervisor that serves as a useful reference on 22 best practices in this area [1]. Some of the more important techniques recommended in the NIST guide include:

Hypervisor configuration: As with traditional OSs, hypervisors can be configured properly or improperly. Example hypervisor misconfiguration problems include rogue virtual machines gaining too much access to underlying hardware resources.

Hypervisor patch and vulnerability management: As with any software, hypervisors are likely to become subject to required patches and vulnerability updates, so hypervisor administrators must put commensurate processes in place.

Privileged operation execution management: Because hypervisors sit between guest OSs and the underlying hardware, privileged operations must be managed carefully during execution.

Enterprise IT and security staff should not be surprised by these types of recommendations for securing hypervisors, because they closely match the types of OS security recommendations that have been around for years. As a general rule, if a heuristic, tool or procedure is in place to protect an OS, something comparable has probably been proposed to protect the hypervisor (see checklist: “An Agenda for Action for Implementing Security Recommendations for the Hypervisor”) [1].

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Secure Development Life Cycle

Zhendong Ma, ... Paul Murdock, in Smart Grid Security, 2015

8.1 Introduction

Since the Smart Grid is basically defined as an addition to the existing power grid infrastructure with an extended information and communication technology layer, there will be virtually no Smart Grid component that does not include software. In order to gain an overview of where security lifecycle assessments can be most complex, it makes sense to distinguish components according to their functionality, rather than their exact position in the overall technical system. Taking this perspective, the Smart Grid is an example of a classical automation system with a field layer (sensors and actuators), an automation layer (communication systems and controllers) and a management layer (centralised systems). One of the ongoing discussions in this context is how much computation actually will take place in a distributed form in substations, customer gateways, etc. and how much of it will be centrally located in different data centres of different stakeholders (distribution grid operator, aggregator, electric mobility provider, etc.). In different countries, there might be different answers to this question. The following discussion takes a Central European view.

A comprehensive overview of functional components in a Smart Grid can be found in (SGCG, 2012). In order to gain insight into the specific tasks accomplished by software-implemented functionality, only three prominent examples shall be discussed in the following, rather than covering all potential components in a Smart Grid. These examples are selected from the power distribution domain and focus on the components in which the introduction of Smart Grid concepts leads to significant changes and extensions of the components from the pre-Smart Grid era.

Example 1: The Customer Gateway

The question of how to interface the energy end users with the management and coordination systems in a Smart Grid is one of the central discussion points in the Smart Grid community, and it can be said that this question is not yet fully solved. Certain appliances, such as heating systems, photovoltaic inverters or charging stations for electric cars will have to be managed in the future and require IT interfaces for this purpose. These can be either be realised on a per-appliance basis, with individual solutions for heat pumps, inverters etc. Alternatively, a central Smart Grid interface for all appliances at a customer’s site can be instantiated that handles all Smart Grid-related coordination. From a security perspective, the latter solution may be preferred because a single interface offers a smaller attack surface, which can be secured in a much simpler manner than a large variety of different interfaces with slightly different purposes.

The German Bundesamt für Sicherheit in der Informationstechnik (BSI) has coordinated a large exercise to define the security measures that are required for such a central interface (BSI, 2012). This interface is a software-heavy component, comparable to a firewall, managing security and privacy for the management of grid-relevant generators and loads on the customer’s site. This can be a private household, but also a larger site of a small enterprise or even an industrial installation. The main tasks of this interface are billing, generation shedding in case of grid congestion and management of load and generation flexibility in combination with aggregators or virtual power plants.

Example 2: Secondary substation automation

Another point in the system where changes are taking place is the secondary substation, which is the last transformer station down the line feeding the low voltage network in which most end customers are connected. It can be seen as a counterpart on the power grid side to the customer interface discussed above. While these secondary substations in the past were mostly mere passive installations with a transformer, fuses as well as hand-operated breakers and re-connectors, IT equipment is finding its way into these substations.

This is primarily motivated by the ongoing smart metering rollout. The majority of European smart meter installations use power line communication for the last mile from secondary substation to the customer, which means that a power line communication endpoint (called the data concentrator) has to be installed in most secondary substations. For collecting metering data from these concentrators, technologies like direct RF links, GPRS or fibre optics in urban areas are used. This results in a large number of secondary substations becoming “online”.

Many grid operators have taken this opportunity to add substation automation equipment to secondary substations for monitoring and remote control purposes, since this comes with marginal additional costs when combined with the data concentrator installation. Functionalities realised here include meter data collection, monitoring and local grid control systems (e.g. for optimal tap position of the transformer), access control and others. This includes a number of communication stacks such as DLMS-COSEM for metering, IEC 60870-5-104 or even IEC 61850 for automation, Modbus for local sensors and actuators. See Chapter 5 for a description of these communication protocols. Again, these functions are mostly implemented in software.

Example 3: Distribution Management Systems

Distribution Management Systems (essentially SCADA systems for distribution power grids) are not new and existed before the advent of the Smart Grid concept. Distribution grids were originally designed for supplying loads rather than carrying away power generated from distributed generators. With the significant rise of generation capacities in power distribution systems, the functionality required from the management systems has changed. Today’s Distribution Management Systems typically contain online details of the medium voltage level. A central functionality is to depict the system status on form of typically large visualisations (screens, projections) and to allow operators to interact with all the active components in the system (switches, on-load-tap-changer transformers, compensation circuits, etc.) The low voltage level is usually not included here, because there is no remote monitoring and control system in place and the level of detail required to depict these systems could not be managed by the low number of operators being in charge of system operation.

The rising number of generators in the low voltage network (mainly photovoltaics) has resulted in two different trends on how to handle this situation in distribution management: the first is a straight-forward extension of existing Distribution SCADA systems to parts of the low voltage systems, usually combined with an advanced alarming solution that allows to draw the attention of the operators to the low voltage only in case of special events. The second trend is to develop low voltage management systems out of the geographical information systems (GIS) that most grid operators maintain for their complete distribution systems. The state of manually operated components such as switches can be, e.g. reported by field operators using an on-line version of the software on a handheld device.

8.1.1 The Development of Software for the Smart Grid

Current trends show that a large amount of resource is and will continue to be invested in software development for the Smart Grid. According to Groom Energy (Energy, 2013), there are over 300 companies that are active in the area of Smart Grid software solutions in the market, offering a broad range of products for energy mangers and operators to monitor and optimising energy consumptions based on business rules, intelligence, and user behaviour. The Smart Grid software vendor landscape includes companies for building management systems, utility bill payment, carbon management, energy management, demand response, industrial control, and sub-meters. The nature of the companies developing Smart Grid software include engineering companies, computer and enterprise software companies, network and communication equipment companies, and companies specialised in embed systems.

Depending on the organization, different system development lifecycle methodologies can be used, for example, waterfall, V-model, Rapid Application Development (RAD), prototype, and the spiral model. The waterfall model is probably the most common development lifecycle method. It is a linear and sequential process, including requirements, design, implementation, verification, and a maintenance phase. Equally popular is the V-model, which extends the waterfall model by associating each of the development phases with verification and validation. The RAD model is an alternative to the waterfall model, which aims at reducing effort for planning, and emphasizes development that results in using more prototypes instead of design specifications. The prototype model focuses on creating prototypes, which involve steps to identify basic requirements and to iteratively develop, review, and revise prototypes. The spiral model is a combination of the waterfall and prototype model, which uses a risk-driven process to guide multiple parties in large and complex development projects. It involves a cyclic approach for defining requirements and incrementally developing and refining prototypes.

It can be seen from this discussion that software is playing an increasingly important role in Smart Grid. Consequently, secure development practices, which are integrated into existing development lifecycles, are mandatory.

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HASARD

Hong Zhu, ... Yanlong Zhang, in Relating System Quality and Software Architecture, 2014

5.5.2 The object system

The object of the case study is an e-commerce system for online trading of medicine. The system is operated by the Medicine Trading Regulation Authority of the Hunan Province, P. R. China, to supply medicines to all state-owned hospitals in the province. Its main functions include (a) customer relationship management, (b) product catalogue management, (c) online trade management, (d) online auction of medicine supply bids, (e) order tracking and management, (f) advertisement release, and (g) a search engine for medicine information. The system was implemented in the J2EE technology.

The system includes the following functional components.

Management component: Supports the management activities, including the management of information release, trading centers, users' membership, manufacture membership, permission of trade and/or production of medicine, and log information of online activities.

Content management: Manages information contents stored, processed, and displayed by the system, such as medicine catalogues, prices, geographical information, and sales information.

Online trading: Provides an interface and facilities for online trading activities and the links to other information contents such as catalogue, product information, and contract templates.

Public relationship: Maintains the public relationship between the organization and its various types of customers, including sending out invitations to the public to bid on auctions, and so on.

Order tracking: Provides the interface and facilities to track the business process of each deal.

Communication management: Provides the secure communications facilities for sending messages and manages the mails sent and received by the system.

Report generation: Answers queries from managers about various statistical data of the online trading and generates financial reports.

The case study was conducted after the object system was released and in operation for more than 1 year. However, the problems in the operation of the system were not revealed to the analysts involved in the case study before the predictions of the system's problems were made. This enables us to see how well the result of quality analysis matches the reality.

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Detection Systems

Clifton L. Smith, David J. Brooks, in Security Science, 2013

Types of Detectors

The principle of detection relies on sensing technology to discover the presence of a person or object within its field of view. That is, if the purpose of security technology is to detect the presence or activities of people, then the detection methods must be devised to respond to these stimuli. Thus, the detection of the presence or activities of people will require the development of appropriate sensors, and is currently a major applied scientific endeavor for the protection of assets.

A schematic approach to the functional components of security detection for the detection of the presence or activities of people requires the following:

A signal must be produced by the person or the actions of the person to be sensed by the detector. The signal could be in the form of reflected light (detected by a camera), near-infrared radiation through body heat (detected by a passive infrared [PIR] detector), a sound (detected by a microphone), by movement when touching a fence (detected by a microphonic cable embedded in the fence), or from a molecular vapor from a package of drugs (detected by specific molecular sensors). All of these examples describe a signal for detection.

The function of a sensor in security detection system responds to a signal for which it is compatible. That is, the sensor is capable of detecting the source that produced the signal, complying with the application of the detector in a DiD strategy. There is a wide range of sensors in security technology systems, including break-glass detectors that are microphones tuned to the frequencies of breaking glass, to X-ray detectors for the presence of explosives. Some other examples of sensors include charge-coupled device (CCD) chips in cameras to detect low levels of light, and the disturbances in magnetic fields produced by the presence of ferromagnetic metals.

Usually, a low-amplitude signal is received by the sensor in a detector, and so it is necessary to increase the level of signal through an amplifier. The signal-to-noise ratio (SNR) is increased by the amplifier to detect a change in the signal strength from the presence of a person. The effect of the amplifier is to increase the sensitivity of the detection function so that it may detect subtle changes in intrusion within the system's field of view. Depending on the type and style of sensors used in the security technology, the amplifier will possess functions to increase the signal strength. Typically, fiber-optic cable could use laser amplification and opto-electronic solid-state amplifiers can be applied to light intensifiers.

The function of the analyzer is to decide if a signal has been detected, or if the only noise has been received. Even after amplification, some signals are still weak and need to be discriminated against background noise. Discriminant analysis is often included in the circuitry to determine if the immediate signal shows that a change has occurred. That is, if a small change in signal quality can be detected, then this effect will indicate the presence of an intruder. Discriminant analyzers incorporate intelligence into the logic circuits of detection systems to better differentiate between active signals and background noise. Thus, these “smart” detection systems are able to discern signals against predetermined criteria to accept or reject the detection signal.

The function of an alarm in a detection system is to indicate that an anomalous signal has been detected. The signal may have been generated by the presence of an unauthorized person or action, and it indicates that a response is required to investigate the anomalous incident. However, the issue of unwanted alarms, where spurious signals are generated by sources other than actual unwanted intruders or actions, requires the authenticity of the alarm condition. It is necessary to have an understanding of the reliability (false alarms through instability of a device) and validity (unwanted alarms through environmental sources) of the detection system to achieve optimum effectiveness for the protection of assets. The discrimination between an actual attack on the detection system and a spurious signal from the surroundings will determine the validation level of the system. The incorporation of intelligence into the discrimination function of a detection system will reduce the frequency of unwanted alarms.

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The IEEE 802.16m Convergence Sub-Layer

Sassan Ahmadi, in Mobile WiMAX, 2011

Publisher Summary

This chapter provides a description of the functional components and protocols associated with the IEEE 802.16m service-specific Convergence Sublayer (CS). The convergence sublayer is located on top of the IEEE 802.16 MAC sublayer and interfaces the MAC sublayer with the network layer protocols. The convergence sublayers of the IEEE 802.16m and IEEE 802.16-2009 standard have very similar behavior; the only differences are in the assignment and use of connection identifiers in the two standards, as well as exclusion of some unused legacy protocols. The Internet Protocol CS (IPCS) and Generic Packet CS (GPCS) are two types of the service-specific CS that are supported by IEEE 802.16m, which are used to transport packet data over the air interface. When using GPCS, the classification is performed in protocol layers above the CS, and the relevant information for performing classification is transparently provided during connection set-up or change. The Asynchronous Transfer Mode CS (ATM CS) and Ethernet CS variants that were specified in the IEEE 802.16-2009 standard are no longer supported in IEEE 802.16m due to a lack of industry interest. Other air interface standards such as 3GPP LTE also use such logical interfaces between their Layer 2 service access points and the network layer protocols. The Packet Data Convergence Protocol (PDCP) in 3GPP LTE performs ciphering and encryption of the MAC PDUs. This is an important difference between the MAC functions of IEEE 802.16 and 3GPP LTE.

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Cloud Computing Infrastructure for Data Intensive Applications

Yuri Demchenko, ... Charles Loomis, in Big Data Analytics for Sensor-Network Collected Intelligence, 2017

Abstract

This chapter describes the general architecture and functional components of the cloud-based big data infrastructure (BDI). The chapter starts with the analysis of emerging Big Data and data intensive technologies and provides the general definition of the Big Data Architecture Framework (BDAF) that includes the following components: Big Data definition, Data Management including data lifecycle and data structures, generically cloud based BDI, Data Analytics technologies and platforms, and Big Data security, compliance, and privacy. The chapter refers to NIST Big Data Reference Architecture (BDRA) and summarizes general requirements to Big Data systems described in NIST documents. The proposed BDI and its cloud-based components are defined in accordance with the NIST BDRA and BDAF.

This chapter provides detailed analysis of the two bioinformatics use cases as typical example of the Big Data applications that have being developed by the authors in the framework of the CYCLONE project. The effective use of cloud for bioinformatics applications requires maximum automation of the applications deployment and management that may include resources from multiple clouds and providers. The proposed CYCLONE platform for multicloud multiprovider applications deployment and management is based on the SlipStream cloud automation platform and includes all necessary components to build and operate complex scientific applications.

The chapter discusses existing platforms for cloud powered applications development and deployment automation, in particularly referring to the SlipStream cloud automation platform, which allows multicloud applications deployment and management.

The chapter also includes a short overview of the existing Big Data platforms and services provided by the major cloud services providers which can be used for fast deployment of customer Big Data applications using the benefits of cloud technologies and global cloud infrastructure.

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URL: https://www.sciencedirect.com/science/article/pii/B9780128093931000027

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