Chapter 5. Understanding DSS Architecture, Networking & Security Issues PDF

Chapter 5. Understanding DSS Architecture, Networking, and Security Issues  Introduction ◼ Managers need to take steps to design an infrastructure that meets the following evaluation criteria: 1. Minimizes support costs and maximizes user...

Chapter 5. Understanding DSS Architecture, Networking, and Security Issues  Introduction ◼ Managers need to take steps to design an infrastructure that meets the following evaluation criteria: 1. Minimizes support costs and maximizes user productivity; 2. Avoids system crashes and other performance problems; 3. Reduces infrastructure impediments that delay the deployment of new IS/IT applications. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-2  Introduction ◼ These three topics of architecture, networking, and security are closely intertwined and are very important issues for building DSS. ◼ Unless one builds a DSS on a stand-alone computer in a secured office environment and keeps the computer under the watchful eye of the manager who is using it. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-3  DSS Architecture and Infrastructure Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-4  DSS Architecture and Infrastructure ◼ The tools for building the user interface are sometimes termed DSS generators, query and reporting tools, and front-end development packages. ◼ A thin-client architecture, where a user interacts using a Web browser. ◼ Thick client architecture, where a program resides on a DSS user’s computer. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-5  DSS Architecture and Infrastructure ◼ The DSS architecture and network component refers to how hardware is organized, how software and data are distributed in the system, and how components of the DSS are integrated and physically connected. ◼ Networking issues create challenges for many types of DSS, but especially for a geographically distributed, multiparticipant DSS. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-6  DSS Architecture and Infrastructure ◼ A DSS architecture can often be diagrammed in terms of four layers: 1. the business decision process flow chart, 2. The systems architecture, 3. The technical architecture, 4. A user interface design. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-7  DSS Architecture and Infrastructure ◼ The architecture also defines the structures and controls that define how the platform can be used, and the categories of applications that can be created on the platform. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-8  DSS Framework and Architecture Issues Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-9  Defining the DSS Architecture ◼ An architecture document helps developers work together, improves planning, increases the development team’s ability to communicate system concepts to management, increases the team’s ability to communicate needs to potential vendors, and increases the ability of other groups to implement systems that must work with the DSS. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-10  Defining the DSS Architecture ◼ DSS architecture should define and specify the following components: 1. Database or databases 2. Model or models. 3. Software tools for users to access the database and the models, and software tools that system administrators can use to manage the database and the models. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-11  Defining the DSS Architecture ◼ DSS architecture should define and specify the following components: 4. Hardware and operating system platforms. 5. Networking and communication capabilities needed to connect the hardware platforms.. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-12  A Client/Server Architecture ◼ Taylor explains that client/server architectures are: 1. A combination of a client or front-end portion that interacts with the user and a server or back- end portion that interacts with the shared resource. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-13  A Client/Server Architecture ◼ Taylor explains that client/server architectures are: 2. The client and server have fundamentally different requirements for computing resources such as processor speeds, memory, disk speeds and capacities, and input/output devices. 3. Scalable Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-14  Networking Issues ◼ Typical physical connections for hosts include Ethernet, token ring, serial line, and modems. ◼ Communication languages on computer networks are referred to as network protocols. ◼ A network protocol is a set of rules and formats that governs how information is sent and in what format it is sent. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-15  Sharing Resources ◼ The fundamental purpose of computer networks is to provide access to shared resources. ◼ A LAN has several primary components: 1. A network interconnection and hubs. 2. Network Interface Circuitry (NIC). 3. The shared resources, like a database server, each with their own NIC connected to the network. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-16  Sharing Resources ◼ A LAN has several primary components: 4. Software on a personal computer that uses the NIC to access the shared resources. 5. Software on the shared resource that coordinates with the software on the individual machines to provide access to the shared resources for users. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-17  Sharing Resources ◼ A NOS is an operating system that manages network resources. It manages multiple requests concurrently and provides the security needed in a multi-user environment. ◼ A wide area network (WAN) is a much larger network than a LAN, and all machines are not directly connected. A group of LANs are often connected to form a WAN. LANs and WANs can be directly connected to the global Internet. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-18  Connecting the Resources: TCP/IP ◼ The general concept of connecting a network of dissimilar computers arose from research conducted by the U.S. Defense Advanced Research Projects Agency (DARPA). During that research, DARPA developed the TCP/IP suite of protocols to communicate among networks, and implemented a network called ARPAnet, which later evolved into the Internet. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-19  Connecting the Resources: TCP/IP ◼ Also, the Internet is a packet-switched network. A packet-switched network transmits information in small segments, called packets. If one computer transmits a lengthy file to another computer, the file is divided into many packets at the origin and then reassembled at the destination. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-20  TCP/IP Protocol ◼ The objective of TCP/IP is to get data from one host to another host, with the assumption that the connection may be difficult. IP provides three capabilities: 1) a delivery service; 2) a means to fragment and reassemble data packets; and 3) routing functions to move data packets on the network. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-21  TCP/IP Protocol ◼ The TCP/IP protocol suite includes a number of protocols or rules. ◼ The Internet Protocol is a low level protocol that transports raw data over networks. ◼ The Transmission Control Protocol (TCP) sends data between programs using IP. ◼ As with all other communications protocol, TCP/IP is composed of layers. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-22  Why TCP/IP? ◼ The growing acceptance of TCP/IP is due to several factors. ◼ First, TCP/IP has been used since the early 1970s. ◼ Second, in the early 1980s it was distributed as a core part of Berkeley’s UNIX Version 4.2 and UNIX workstations became primary servers on the Internet. Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-23  Why TCP/IP? ◼ Third, TCP/IP is dependable. ◼ The modular design allows the construction of very large networks with less central management. ◼ The Internet Protocol was developed to create a network of networks called the Internet. Individual machines are first connected to a LAN. TCP/IP shares the LAN with other uses Business Information Systems (BIS), Faculty of Commerce, Assiut University Slide 1-24