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As an information system, a computer aided software system needs the capabilities to deal with the variety, complexity, and changes of design needs. Three basic strategies to deal with the variety, complexity, and changes are to (i) modularize system architecture, (ii) make functional components flexible, and (iii) support system integration (Bi and Zhang 2001a,b; Bi et al. 2008). To implement these strategies, functional modules must be interoperated, collaborated, and integrated. Therefore, servers and networking technology play a significant role to advance CATs. A server acts as an agent to accept and perform tasks and to generate the results of a task to requesters. Networking allows a number of the servers working collaboratively to solve a holistic problem, whose solution consists of a set of sub‐solutions that are used to divide subproblems with the given constraints. For example, networking makes the following technologies possible in computer aided application systems.

Parallel computing is a type of computation in which many calculations or the execution of processes are carried out at the same time. Large‐scale design problems should be decomposed into smaller ones, so that the sub‐solutions can be obtained by using a number of computing resources concurrently. Parallel computing may refer to parallel processing by a set of central computing units (CPUs) or graphic processing units (GPUs) in one computer or parallel supercomputers containing hundreds or thousands of processors, networks of workstations, multiple‐processor workstations, and embedded systems (Foster 1995). Computer aided systems, especially CAE systems, need parallel processing capabilities to achieve scalability in solving complex design problems, which may involve multiple physics, transient dynamics, or large‐scale coupled models.

Hardware in the loop (HIL) simulation is a type of real‐time simulation for the design of real‐time control systems. In HIL, the machine or physical part of the system is networked with the control model through actuators and sensors. The rest of the system is represented by the mathematic model in the simulation. HIL assists in developing and testing complex real‐time embedded systems while considering the complexity of the real‐world system. HIL simulation shows how a control model responds to realistic virtual stimuli in a real‐time manner and can be used to determine whether the mathematic model for a physical system is valid (MathWorks 2018).

Distributed database is a storage solution where a common processor accesses the data in a distributed system. Data may be stored in multiple networked computers in the same location or can be dispersed over a network of interconnected computers. A system server distributes collections of data across network servers or independent computers over intranets, extranets, or the Internet. Computer aided systems benefit from the distributed databases in increasing the scalability, modularity, reliability, and flexibility of systems (Wikipedia 2019c).

Cloud computing is the delivery of computing services such as data collections, computing, data mining, analytics, storage, servers, and more over the Internet for faster innovation, flexible resources, and economies of scale (Microsoft 2019). Computer aided systems greatly benefit from cloud computing over a number of aspects. Firstly, cloud computing allows single users, freelance designers, and SMEs to participate in the entire design processes of complex products; large and multinational companies can work with several hundred SMEs and individual designers to seek design solutions. Secondly, this helps to reduce an overall cost of the design and development processes. Cloud computing helps to reduce the investment on computer aided systems. Traditionally, commercial software tools are associated with the licensing and training costs as well as the additional cost on maintenance, software and hardware upgrades, IT personnel, power requirements, and rental costs for additional space. Cloud solutions offer an alternative where licensing costs are substituted with a subscription fee and the expenditure is substantially reduced since the resources are shared by users in the cloud. Thirdly, most of the cloud services offer pay‐as‐you‐go options, where one pays only for the used computational resources. Such services reduce the overall cost for both the provider and the client since the service loads are customized to the needs (Harish 2018).

Manufacturing systems became highly distributed for enhanced flexibility and adaptability to meet the needs of regional markets promptly. The high‐speed 3G, 4G, and 5G wireless networks helped to mobilize product information so that the PLM could be accessed by mobile apps. From the perspective of information technology, we have entered the fourth industrial revolution, where nearly every device will be networked, which allows continuous data streams to populate in memory databases. The Internet of Things (IoT) will transform the manufacturing sector in the coming years. More and more cloud‐based solutions will be available to manufacturing enterprises to support their operations (Bi et al. 2014; Wang et al. 2014; Morley 2014).

Virtual enterprise (VE) is a temporary alliance of businesses for partners to share core competencies, resources, and skills in order to take advantage of emerging business opportunities. VE is facilitated by computer networks (Wikipedia 2019d). The core competencies, resources, and skills in VE are mainly for CATs. Figure 1.17 shows that using the virtual environment over the Internet, designers across different regions, domains, enterprises, and disciplines can collaborate on all of the CAD activities involved in the lifecycle of product development (Wu et al. 2015; Wu 2014).

Figure 1.17 Computer aided collaboration in virtual environment (Wu et al. 2015; Wu 2014).