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- Digital Technology – Part
- Basic concepts
- Industry 4.0 overview......................................................................................................................................................................................................................
- The role of Information Systems
- Mega-trends
- Cloud computing
- Data intelligence
- Collaboration..............................................................................................................................................................................................................................
- Mobility
- Pervasive computing
- Business Innovation – Modal ICT
- Business information value chain
- Producing value: the business information value chain
- The IT Infrastructure – Technology aspect
- The Interdependence Between Organizations and Information Technology
- Information Systems: more than PCs
- The two-way relationship between Organization and ICT
- The marriage between Organization and ICT
- Effects on the Organizations
- Contemporary approaches to Information Systems
- The socio-technical perspective
- The importance of architecture
- “Infrastructure” versus “Architecture”.....................................................................................................................................................................................
- The purpose of the Enterprise Architecture
- Introducing Enterprise Architectures, The Zachman’s Framework
- Introduction to ARCHIMATE
- Levels of abstraction in architecture
- Enterprise architecture and its representation
- Enterprise Architecture: describing coherence
- Main concepts
- ArchiMate core
- Service notation (ArchiMate)
- Layers and services
- Service: an important concept for digital technology
- Anatomy of business service
- Service oriented architecture
- Layers and services
- Serving relationship
- Business layer...........................................................................................................................................................................................................................
- Processes
- Basic process components
- Aggregating elements
- Technology Infrastructure layer
- Infrastructure components
- Technology level: different aggregation levels
- Process
- Grouping
- Derived relationships
- Data sources, database technology and data formats
- File Organization Terms and Concepts
- Why a DB? Problems with Traditional File Processing
- First point: how can I share data between application?
- Problems with the Traditional File Environment
- Database Management Systems
- Human Resources Database with Multiple Views
- Logical data models - Relational DBMS
- Logical view Relational Database Tables
- The 3 basic operations of a Relational DBMS
- Capabilities of Database Management Systems
- Integrating data: towards ERPs
- Designing relational Databases
- How to design a database Conceptual model An Entity-Relationship Diagram
- Normalized Tables Created from Order
- BIG DATA
- The challenge of Big Data
- Typical database Size (order of magnitude)
- Big data: many sources Variety
- Non-relational (Not-only relational) Databases
- Big data: Velocity
- Data exchange and formats
- Data sources 2nd part: IoT, Mobile computing
- IoT
- Factory 4.0 pillars
- Representing IoT elements in ArchiMate
- Rest API
- IoT in ArchiMate.......................................................................................................................................................................................................................
- The problem of object identification.............................................................................................................................................................................................
- Identification – basics...............................................................................................................................................................................................................
- Technologies needed:
- Identifiers:
- NFC Near Fiels Communication
- Mobile computing
- Contemporary Hardware Platform Trends
- Localization technology
- What are Beacons?
- How do beacons work?
- Comparing Beacons with similar technologies
- COVID-19 contact tracing
- How to solve Privacy problems?
- App Immuni..............................................................................................................................................................................................................................
- Possible issues
- The Paradigm Shift Servitization and Cloud
- The NIST framework for the definition of Cloud Computing
- Cloud Computing – 5 essential characteristics
- The service models (delivery) - SaaS
- The service model (delivery) - PaaS...............................................................................................................................................................................................
- The service model (delivery) - IaaS................................................................................................................................................................................................
- Deployment models
- Cloud usage within the firm
- Cloud Computing and ICT as-a-Service..........................................................................................................................................................................................
- Technological foundations – Virtualization
- Virtualization – What is it?
- Technological foundations – Virtualization and consolidation
- Technological foundation – Virtualization Characteristics
- Technological foundations – Virtualization Hypervisor
- Technological foundations – Multitenancy
- Economics of Cloud Computing: General principles
- What elements are opposing the adoption of Cloud solutions within your company?............................................................................................................
- The real benefits
- Key aspects to consider for Cloud Service evaluation
- Cloud major benefits
- Adoption paths and ongoing trends (Cloud Journey)
- Cloud journey: strategic assumptions
- The decision process: mixing strategic and operative perspectives
- The implementation journey… towards a hybrid Information System
- Public SaaS adoption
- Social media as data source...................................................................................................................................................................................................
- Social Media
- Example CRM
- Example of ISTAT......................................................................................................................................................................................................................
- PROJECT MANAGEMENT AND IT PROJECTS............................................................................................................................................................................
- APPROACHES
- UNCERTAINTY
- INNOVATION
- SIZE
- PROJECT MANAGEMENT TYPES
- PROJECT LIFECYCLE PHASES
- THE 10 SOULS OF A PROJECT
- WORK BREAKDOWN STRUCTURE..................................................................................................................................................................................................
- GANTT CHART
- ORGANIZATIONAL BREAKDOWN STRUCTURE
- RACI MATRIX
- RESOURCE PLANNING
- GRID INFLUENCE/INTEREST...........................................................................................................................................................................................................
- RISK ASSESSMENT
- EXAMPLE RISK PLAN......................................................................................................................................................................................................................
- WATERFALL
- BASIC ASSUMPTIONS WATERFALL
- WATERFALL PROS AND CONS...................................................................................................................................................................................................
- WATERFALL VS AGILE
- LEAN SOFTWARE DEVELOPMENT
- AGILE SOFTWARE DEVELOPMENT VALUES
- SCRUM
- HOW SCRUM WORKS
- ROLES IN SCRUM
- ARTIFACTS IN SCRUM
- CEREMONIES IN SCRUM...........................................................................................................................................................................................................
- DIFFERENT METHODOLOGIES FOR DIFFERENT PROJECTS
- Ethical and Social Issues in Information System
- Behavioral Targeting: Your Privacy is the target?
- Understanding Ethical and Social Issues Related to Systems
- The relationship among ethical, social, political issues in an information society.........................................................................................................................
- Ethics in an information system
- ACM Code of ethics – Association for Computer Machinery
- Introduction to security and privacy – part
- Threats
- Some common principles
- Security – definitions
- Security – properties
- Authentication
- Service availability
- IT resources management.............................................................................................................................................................................................................
- Privacy regulations
- Where are our data?
- Data Collection and Privacy
- Secondary use of information: Privacy threats
- Privacy law
- Some definitions
- Introduction to security and privacy – part
- A small recap
- Data protection principles – Article
- Lawfulness of processing – Article
- Minimal measures for digital data
- Responsibilities of controller & processor: Data breach notification – Article
- Security and cloud computing
- Technologies for security
- Encryption
- Another ingredient – Hash functions
- Cybersecurity
- Knowledge Management and Big Data Technology
- Data, Information , Knowledge DIKW pyramid
- Components of a data warehouse
- Multidimensional data model
- Multidimensional representation
- Data Warehouse
- Dimensional schema (star) example
- Operations on multidimensional data
- Managing Data Resources
- Establishing an information policy
- Data analysis and data mining
- Big Data Technology aspects
- Managing volumes: Scaling
- Using Databases to Improve Business Performance and Decision Making
- Text mining
- Data mining
- Web mining
- Extracting knowledge: Data mining...............................................................................................................................................................................................
- Association rules
- Clustering
- Classification
Basic concepts
All the systems inside an organization are interconnected, there are information flows among them. When you build systems, you need to be sure that all the interconnections are well designed, you also need to identify the components, and you have to decide how many components to have, because you have separated systems or integrated systems. Each user can see one part of the system and not the whole part of the system, so the customer calling will see the interface to him provided by the system to answer to his questions. When we talk about architecture, we want to see how systems are connected to each other.
Industry 4.0 overview
There are other systems where you can have information flow and the need to connect many different components. This is the industry 4.0 paradigm. There is the typical production plant, which gets from suppliers the materials that are needed, and of course they need also to support the logistics and manufacturing activities. So, there is the production plant, where there are clients, and the company needs to give products to clients and monitor the use of objects produced, so the company might have the need of “sensorized” things. For example, if you produce dresses you can put a tag on a dress that can make you track the dress in the shops, in this way you create things which are equipped with tags and you can use this information through the Internet. You can get all these data from all these systems, from the production, logistics and sensors and then all these data can be analyzed. The Big data issue is that we need to analyze all these data because this can be useful in a company in order to predict whether some machine will have some problems in the future, this is called Smart Maintenance. You can avoid damages and improve the global functioning of your production. You want to do an analysis on the machines, on the suppliers, on the services, you are providing to the clients; then all data collected are put in Cloud computing, that provides a theoretical infinite source to store data and do computations. Many systems here need to be connected: you can focus on cyber security; you want to guarantee privacy to your clients. So, you need to tackle all the issues which are related to exchanging data between these systems including new sources of data that are coming from machines, and from sensors. The focus of our class is understanding how to connect these things.
The role of Information Systems
Of course, the information system is like a backbone for a company: you need to use information for all the activities and of course you want to improve systems to achieve goals and you can have different strategic business objectives. Growing interdependence between ability to use information technology and ability to implement corporate strategies and achieve corporate goals. Business firms invest heavily in Information Systems to achieve six strategic business objectives:
- Operational excellence
- New products, services, and business models: different degrees in order to upgrade the system, this can be done developing new products and services or even business model (organizing the way to operate using that technology).
- Customer and supplier intimacy
- Improved decision making → you want to improve decision making, so improve a service if there are problems.
- Competitive advantage: we could get with some innovation some competitive advantage.
- Survival: you need to upgrade your system to survive to the market.
Mega-trends
ICT trends are shaping the present-day ICT market thanks to the introduction of new ways of viewing technology. “Mega” trends cut across all ICT-based markets and lead to a radical rethinking of traditional paradigms. New approaches to ICT-based product development, customer experience and innovation are the core elements of market transformation How are information systems transforming business, and why are they so essential for running and managing a business today? Business versus technology. What are the components? Where to start from? Which is the role of new IT-related developments (mega- trends) o Cloud computing o Data intelligence, Artificial intelligence, Big data o Collaboration, Structured processes, Social media o Mobility, Mobile computing o Pervasive Computing, Internet of Things
Collaboration
We have a lot of unstructured communication. We want to create some collaboration flows and so structure processes, to get to a structure process flow, in order to be able to manage our interaction in an ordered way. Collaborative Enterprise In the Official standardized Workflow, you need to be able to decide for the possible requests, then there is a responsible, and then there is a management function (taking orders, providers). This is the order of interactions expected. In reality the flow is much more informal, there are other flows while you are doing the process! What companies want to do is to structure the process and enable the communication in an informal way.
Mobility
One technology, which is used to collect data, is the use of mobile devices like cell phones. This can be used to collect data, to work in a mobile way, so interact from different places and this can be used to increase productivity. What we need to be able to understand is how this connection is going to happen in processes, so how to use data generated by these devices and integrate these data into an information system. The concept is: try to understand what it means to integrate mobility and use it in our system. One focus is the ability to locate the users, for example if we are in a museum and we want to have information about a picture, which is available in the museum, there are several ways to provide this like using a smartphone to provide this information to the user. The important thing to capture is where the user is (the picture) and to link it to a service provided (mobile phone). We need some location technology to do that. There is a trend toward the use of smartphones and other types of mobile devices adopted. We want to focus on different aspects and how to use the other technologies: o Abilities to analyze data o The cloud platform o Legacy Enterprise IT Infrastructures: integrating these to the existing information of the system of the companies, the Legacy is a system already been used by the company o Enterprise Dashboards: gather information from the mobile, like the position. With the mobility we can see that we can gather information from different positions.
Pervasive computing
In general, we want to transform objects into smart objects, something which can be tracked, for example our dresses sold can be tracked or we can gather users’ preferences like favorite colors of the customers. We can make possible the interaction between applications and real world, gathering information and acting directly on the environment. Internet of Things. the network of physical objects - devices, vehicles, buildings, and any item embedded with electronics, software, sensors, and network connectivity - that enables these objects to collect and exchange data. The size of the market is increasing, the units able to collect data from the different sources are increasing. There is attention now on:
- Digitalization: interest in not only getting the experience to get the data, but also the ability to observe the behavior of your machines. You have a twin from your machine where you can do simulation to see possible actions on a machine and analyze the behavior of it.
- Intelligent: we want intelligent objects, autonomous like cars, be able to analyze data.
- Mesh (network): block chain and smart spaces, how to create them and how to manage them. There are cross cutting aspects like Digital Ethics and Privacy, and Quantum Computing. Business Innovation – Modal ICT ICT can be considered as a commodity, so it is something which can be used like a service, like electricity, where we can switch on and switch off the light. ICT can be considered as innovation in a company if it is something new, we want to exploit ICT as a strategic goal as something new, in a company this can be used to gain competitive advantage. The role of ICT. We can improve efficiency, manage processes, and also introduce innovation in our company, and we discuss it through the business information value chain.
Business information value chain
We want to be able to increase the profitability of the firm and keep the position toward strategic goals. Doing data collection, I am using data in our system. We have to split 2 different points of view of the Value Chain:
- At the top, we think about production companies to manage Supply Chain, the Enterprise, Customers, and the Knowledge Management that derives from these.
- At the bottom, we have the Management view which deals with Planning, Controlling and Decision Making, which are essential to manage the process, improve it and to take strategic decisions.
Producing value: the business information value chain
Business organizations are hierarchies consisting of three principal levels: Senior management, Middle management, and Operational management. Information systems serve each of these levels. Scientists and knowledge workers often work with middle management.
Information Systems: more than PCs
Using information systems effectively requires an understanding of the organization, management, and information technology shaping the systems. An information system creates value for the firm as an organizational and management solution to challenges posed by the environment.
The two-way relationship between Organization and ICT
Two point of view to introduce a new technology:
- Requirements pull you need a new technology. So, from the organizational point of view, you have the need to provide a new service that an Information technology can support. You need to develop a new project which is developing this technology for you, or you have to decide which technology you can find in the market to realize your requirements.
- Technology push: on the other hand, in many cases when you consider a competitive advantage you have to use a new technology, otherwise if you don’t use a new technology you will lose it. You have to use a new technology, because otherwise different companies will adopt it, and if you don’t use it, you will lose your competitive position. In this case the technology is coming from the market, it is available, and you need it to incorporate into your organization. The way to do this is mediated from different factors which influence the way some technologies can be accepted or not in a given place.
- Working environment
- Culture
- The way you structure the company
- Business processes
- Different management decisions: internal to the company or some external factors
- Politics The goal is to analyze how projects are done and understand the different factors.
The marriage between Organization and ICT
Implementing Information Systems has consequences for task arrangements, technology, structures, and people. According to this model, to implement change, all four components must be changed simultaneously. In order to implement an Information system, we have to consider:
- Structure
- Technology
- Normally used by People
- Task
Effects on the Organizations
Information systems can reduce the number of levels in an organization, by providing managers with information to supervise larger numbers of workers and by giving lower-level employees more decision-making authority. You might change the structure of the company because you could provide some data analysis tools that simplify management activities, so the structure could become less complex.
Contemporary approaches to Information Systems
The study of information systems deals with issues and insights contributed from technical and behavioral disciplines. Several approaches are taken from the Information systems the 2 categories are:
- Technical approaches (Management science, Computer science, Operations Research)
- Behavioral approaches (Psychology, Economics and Sociology) IT systems evolution → We can imagine we start from a system that already exists and we want to introduce something new. IT Systems are evolving systems
- From current system → AS – IS
- To future system → TO – BE
The socio-technical perspective
In a socio-technical perspective, the performance of a system is optimized when both the technology and the organization mutually adjust to each other until a satisfactory fit is obtained. One approach, which used to put together Technology and Organization, is trying to study the technological and organizational aspects in a different way from the other alternatives considered. You see that when you start you will have some distance between what will be technologically variable and what is considered from the organizational point of view. So, you try to develop your design of the project, in order to put together these 2 views to get to something which is through a set of alternatives that in the end will be our system developed. So, we have a Final design of the technology and a Final design of the organization to have a system that is going to properly work in a company. We have to avoid having only Technological projects and also to have only Organizational projects, otherwise the system will not satisfy the requirements, even if we have Technology push or Requirements pull. We need to have both of them in order to have the system properly working.
The importance of architecture
Enterprise Architecture:
- How to organize components: how to design the architecture of the system
- Bridge between Technology and Organization
- Networked e-business: interaction
- Internal architecture: coordination between components we want to adopt. Actors → Four main actors:
- Suppliers of hardware and software: suppliers of the components
- Business firms
- Managers and employees: internal resources like managers and employees who are going to use the system.
- Firm’s environment (legal, social, cultural context): the environment is fundamental, because some systems could be adopted in some countries and in other not adopted because of the cultural context in which they are considered. The ICT Professional’s Curriculum Vitae ICT deals with:
- Technology
- Business fundamentals
- Information system The last one is a system that is considering business and technological aspects. On the one hand, thanks to Information system, we need to be able to communicate (teamwork) and on the other hand, we have to provide an overview of the system since we need to be able to do analytical and critical thinking in order to consider an information system development. Building an IS can be tough! You have a system which is containing different software components. Another view is the infrastructure of the system: how the information system is interconnected. There are other aspects related to communication and organizational structure which are also important. Finally, also users and people involved in the service you provide, when you provide a system and a service you have to calculate the needs which underline all these perspectives.
“Infrastructure” versus “Architecture”
You want to design your system not only going through an infrastructural way, but also calculating the Architecture: you plan how to put your components together in order to have a system which is manageable, who is going to do what, and this is going into the direction of some components that are linked together and that are supporting the different aspects. The architecture is an enabling factor to provide service in a way that is in line to provide the company needs. ICT Infrastructure is a set of hardware and network technologies that can support enterprise operations, enabling the use of resources and services. ICT Architecture is a group of static and dynamic (and in-between logics) granting alignment between enterprise’s strategy and operational activities.
Enterprise Architecture – A framework
What Zachman said is told in this framework. On the columns there are the questions of this framework: What, How, Where, Who, When and Why. Our scopes are the rows: Contextual, Conceptual, Logical, Physical, and then Detailed representation. In the contextual row: there is basically texts, so you want to describe things, you use reports and write the main lists you want to have (Function), requirements and constraints to consider your planning, you have a geographical perspective (Where). Then we come to what is more important which is being able to represent this through the Conceptual model. Then there is the Logical data model, so if you study the Relationship data model is one type of model for the system. You don’t have to consider specific system but design the system. Going on you have to consider physical aspects with Physical models, so you want to create indexes so that your access to the data is more efficient, you want to store data giving different access to people. The first column is that you have a list of data and you have details of the list that is represented. The same can be done for all the columns, so you have the functions, so you go from a list of services you want to provide so the Business processes to represent them in a Business process model. We will focus on design the Technology infrastructure: how people are going to access to the system. We will focus less on motivation. We will distinguish between what are the conceptual concept we have to manage and the project that is involving them and how they are supporting the physical infrastructure. Then you will have to design exactly how you store these data, so an implementation of the different relations into tables and database, the indexes, the file, all things needed to manage data in your Data Management system.
Introduction to ARCHIMATE
ArchiMate is a graphical notation, we want to draw some pictures which are showing us how the system is done. This is following the approach we have seen in Zachman. ArchiMate is a graphical notation which uses colors to represent the system more clearly. There are some elements in the notation. We will focus on what is called the ArchiMate Core, a set of symbols which is always used when using ArchiMate to describe structures of an IT system which is providing services to customers. We saw in Zachman different perspectives, different aspects but we want to have an integrated design. So, we design one system, not several, different systems. But of course, when the system is complex, with many elements we cannot see it in just one picture, so we will have different layers of a system. The goal of the notation is to understand the system and all the component, to facilitate the governance. This is a reference model for your company that will be used to understand how things are related. One important thing on which is important to focus from the measurement point of view is change management. We have already a system, we need to create new functionalities, or to reorganize the system to integrate new technologies. We have to represent which elements are going to change, which elements are going to be transformed. It is a way to design a system understanding what are the changes that will be affected by a given problem. Of course, this is helping in understanding the relationship between the different elements and we want to know if I do a change in one part of the system, which are the other elements that will be affected by this change, and this is important when you are doing an IT project because you have to manage this change and to create the different steps for managing it.
Levels of abstraction in architecture
We have several architectures when we talk about IT system. There is an increasing abstraction that is going from the instance architecture to the reference architecture. We will work on a system of one organization to provide services to customers. So, we work on an instance architecture. When you design a system, you design an instance architecture. The instance is your system. It is the architecture of your system. However, systems are changing over time and in many cases, you want to add another part in your system which is similar to different cases. For instance, you are managing many shops and you want to add a new one. So, for doing that, you create standard architecture which is an abstraction of what is an architecture that you can use in that case. So, to create a new shop you already have a blueprint giving you a basic representation of what you have to develop and normally you have to do some personalization to make it works for your single case. So, the standard architecture is something that is in your library of architectures that you can use when you have a similar part of the system to develop inside the system itself. A standard architecture is a reusable diagram that you will re-use again when you have similar part of the system to be developed again. It can happen that you have to do the same project but in different parts of your organization. There is another architecture level, we call reference architecture. Reference architecture is the case when we have several organizations that are putting together efforts to create an architecture that can be used in a given community. For instance, if you have different companies which are working in the same supply chain, in the same sector, so you can create a reference architecture for e-commerce, for IOT systems, for big data, what you are doing is: you are trying to define the terms that everybody is going to use, to have systems interacting with each other. So, we know that we have systems that are going to interact, we cannot expect that there is one design for all of them, but we can create reference architecture to establish which are the main references, define them and of course to do this we can use notation to represent the architecture. It is a reusable architecture for several organizations. So, this architecture can be used by different organizations in different companies.
Enterprise architecture and its representation
- Zachman: definitions of framework based on aspects and perspectives
- ArchiMate (Open Group modelling notation) We have started from Zachman, so we saw there are aspects and perspectives, the columns and the rows and we will adopt this new notation that is called ArchiMate which is becoming internationally used. There is a group which is called Open Group that re- sharing their result, tools. This is a notation for sharing the design of information systems. When we were talking about Zachman, we were focusing on different questions (What, How, Where, When, Who) and we will focus in our case in the core ArchiMate notation which will be focused mainly on some aspects (what, how, a bit of where and who) and on some of the perspectives: we will go from what is the enterprise model, the conceptual view, so we are going to provide services to customers and this is what we want to do with our system. But then we want to design our system. So, when we will talk about ArchiMate Core we will focus on some of the Zachman aspects. We want to have relations across a given perspective (horizontally but also vertically). We want to see how elements are interconnected. When we talk about conceptual level we will talk about letter to a customer, when we talk about system models, we are focusing on producing documents, we have customers data. We want to have a logical representation of the system. And then we have technology: databases, servers, the notation will be telling us which servers will be used to provide a given service to the customers. So, focus on understanding the elements and relations to be able to describe the system.
Service: an important concept for digital technology
- A service is a (formal or informal) contract between a consumer and a provider about the provision of defined goods and/or services
- The contract specifies the duties and obligations for both parties
- The premise is that the consumer of the goods or service finds some value in using the service, and the provider obtains some benefit too in providing the service. A contract can be formal or informal: for instance, now, you are expecting that Teams is working reasonably with a given performance, but you didn’t sign a formal contract for establishing which is the service level expected from Teams. Different services can provide different service level to establish which are the acceptable condition to perform the service. This is normally specified in the duties and obligations of both the parties. Normally even if we are using an online service we have to sign and accept the condition which are telling you how you can use the service and so on. Service can be an infrastructure service, so I can provide a computational service or can be a service that I can provide such as an editing tool to write a letter.
Anatomy of business service
Another important aspect of services is that they are providing you some functionalities that are provided through some interfaces. Moreover, the service is provided by using some service level agreements which is normally represented (especially if it is an IT system) as parameters that are denoting quality of service. Sometimes we may have different service level agreements. So, for a service you could have a normal mode , an emergency mode if for instance the infrastructure is not working very well. You may have different service level that are agreed with the single consumer or you might offer service at different levels: free services might have lower performances and paid services higher performances. To perform a service in a system you will need physical resources. This is something that the user of the service will not see. The user is expecting just some service level agreed. Physical resources are proving the infrastructure to provide the service. At the consumer level you don’t want to see the physical resources. Example business service SLA (simplified) Service: manage shopping cart in e-commerce application. Typical service level parameters are the ones shown in the table. To define a specific service level agreement, you typically define levels that can be measured, and you can define some functions (Maximum response time that you consider acceptable, Average, Minimum). They come together with the description of not only the cost of the service but also the penalties that will be paid in case you are not respecting. Penalties could be in terms of money or could be compensation. What we see here are the typical parameters that are measured. You have parameters, you agree on who, when, how you are going to measure it and then you are going to define the thresholds that could be maximum, average, and minimum. So, when we are saying that we have a service level agreement we are defining those conditions. So, we know which are the functionalities, interfaces, and conditions. This is creating a service which is used by some users. Users can be at different levels.
Service oriented architecture
This is also in IT systems, emphasizes what is called a service-oriented architecture. You see that you have a service provider which is the one providing the service at given conditions. The requestor must define the possible services which are provided and typically the service provider will publish its services in the service registry. Technologically, this could be done in different ways. Once a list of services provided by a given provider is available in a registry, the service requestor can request to this registry which are the services with some characteristics. So basically, providing some search mechanism for finding the services, find it, and then access to the service of the provider directly. There will not be a central authority which will make this binding, but the requestor will call the services which are provided using the interfaces that have been declared by the provider and stored in the registry. In the service-oriented architecture we will be able to ask for resources which can be for infrastructural level, technological, business to a provider directly. Services are there to be used and are used calling them also possibly dynamically. If I’m a provider, I have to publish somewhere my services, to make them available to somebody who’s going to look for them and then once the service that has to be used has been identified, the requestor will be able to ask the service accessing directly to the provider platform to call the service. This can be done at all the levels. Once you know which service you are going to use you go directly to the provider. Potentially the user knows about the provider service through the service registry but then when the consumer wants to access the service will directly access the service at the provider site.
Layers and services This is what we will study in ArchiMate. We have customers which are served by business services. We are providing business services to the customers. Business services are realized by the business process. So, the business processes are realizing the business services. To support a business process, we need some software components. So here we are served by application services which are realized by application components. The software component is realizing an application service which is serving the business process. The application component must be served by a service infrastructure otherwise it cannot be executed, and the infrastructure service will be realized by infrastructure components. Relationship between the different elements represented in ArchiMate. Infrastructure component is the Node component, which is for instance a service, a software and so on which is providing, realizing an infrastructure service.
Serving relationship
Here we have some examples. Service relationship is used to connect different layers. Here connection between the business layers and the application layers. The service is serving process. Another way to look at it: the register Order is using the order recording. Pay invoices is served by payment service.
Business layer
If we want to describe completely a business layer, we want to provide a business service. This is realized by a business process. Somebody will have to execute the business process. So, we will have the responsibility for the business process. So, you will always have a business role assigned to a business process. So, you see here the active element. You need to say who’s going to be responsible of that business process. In our exercises, in many cases, it will be the company which is providing the service. In the other part we can see the connection to the application layer. To perform a business process, it should be supported by an application service. We can also be capable of decomposing the business process in many subprocesses.
Processes
- Flow of activities with the goal to provide a service
- Activities can be considered as processes
- Activities linked by a trigger relation
- Events (significant ones) How processes can be detailed? We need connectors between the different activities of a process, and this is a trigger relation.
Basic process components
If we are taking our starting representation of the business level, how do we detail a business process? A business process might contain:
- Subprocesses
- Trigger relation
- Event Symbol of the event is: We put events only if they are important for us. The ending event might be interesting if you might end the process with different states, so you want to represent those ending events which are the final states of your process. Here we have a new arrow that is the trigger arrow. You have your company which is responsible of the process. At the beginning we were focusing on “John reads a book” (business role, business process, business object). Then we introduced that we are actually providing a business service. Here now, we are providing a new element: we need an interface (considered as a component of the business role) for providing this service which is assigned to the business service. For a given business role we may have several interfaces to provide the service, for instance if we have more channels (here we have just one channel that is the web channel). Others could be telephone service, web services for the same process and service.
Infrastructure components
We have in a node its elements. The node is an active element, it will be able to execute the software. You can have different types of software: the application software that is the realization of the application that we are talking about, the DBMS for storing data and then sometimes we want to also show the specific operating system. In the infrastructure level you will see where the infrastructure is running.
Linking infrastructure components
Communication network: → How you link the nodes?
- LAN (Local Area Network) → in campus area or within a company
- Internet which is not considered very reliable for the security’s POV If they are not connected at the infrastructure level, they are not going to exchange data at the application level.
Technology level: different aggregation levels
Here we can have different elements listed together. You can have device within server and inside the device you can see the software component. And you might be interested to mention the functionalities and services. You can nest the different levels. You decide the level of detail you want.
Process
Junction
- And – both paths are taken
- Or - alternative As we said we might have different parts in a process and basically here we have an example. What we have here are 2 paths in a process. Here we have a process with a starting and ending event and then start activity which is followed by 2 paths. The full junction is telling us that we are going to do both activity 1 and activity 2 and then you can join the path. If we instead have an alternative, we can use another symbol which is a junction that is empty. If we have alternative paths in a process you can use this symbol to follow them. If it is important for you to specify the condition you can express that you go one way just by labelling the activity in an appropriate way which is telling you why you took this way. If you have to go in a process to do 2 different things for instance if I’m preparing parcels and if it is heavy, I go this way and if it is light, I go to the other way. In activity 1 I will write “heavy sending” and in activity 2 I will write “light sending”. You can also have events along the 2 paths, and you will express them if they are relevant. To wrap it all up
Grouping
The grouping element is used in cases like this, where we want to show, that there is something together. This is used especially for things that are external, that are providing a given service. We are not inserting something new; we want to say just that they are aggregated.
- Aggregate elements together
- Aggregate elements of the same (external) organization We use this aggregation component if we want to take this element out of the group. All these elements and their relations belong to a group, that in this case provides a service. This is just to show that we might use group to show things that are used together. To put things together we can use aggregation and composition. When we use the group, as in this case, we have the empty arrowhead, we are saying that this process exists beyond belonging to a group, so has his independent life. So, each element in this group has its own life without being linked to the group. So, thinking about the interface, the interface belongs to the component, so, it has the arrowhead all black, to say that it hasn’t an independent life (composition).
Derived relationships
Relationships ordered by strength:
- Influence (weakest) → it is just a link between two elements like the one that links a node to LAN.
- Access
- Serving → for the serving relation
- Realization → for the realized action
- Assignment → for an active component
- Aggregation
- Composition (strongest) If two structural or dependency relationships r:R and s:S are permitted between elements a, b, and c such that r(a, b) and s(b, c), then a structural relationship t:T is also permitted, with t(a, c) and type T being the weakest of R and S.
Data sources, database technology and data formats
To recap, we look at ArchiMate and we try to locate which are the different element of an information system. We can use framework approach, using ArchiMate we can divide the different elements in three layers:
- Business layer: what a company is doing to serve the customers
- Application layer: how system interacts with the business process that supports
- Technology layer: Different technologies that we are using, such as functionalities, software components and storing data We want to understand how to manage data of different types and which are the problems in manipulating data that comes from different sources, as happen usually in an organization. For storing data, we have DBMS and then we will discuss the issues related to a traditional Information System which is managing Big Data. When we are talking about model, we will start with the relational model. At the business level we have business services, for example answering customer complaints, requests, and order and so on. When we talk about data at this layer, we will talk about business level objects, like costumer’s answers, enrollment... instead, when we talk about application layer, we have all the functionalities that we need to manage data or to exchange them between application because we want to use them from an app to another one. At the technology layer we want to present data objects that we want to manipulate. We are still not thinking of the physical objects that are stored at technological level, but we want to have objects that are understood by the application. We want to be able, at this level, to store data and develop software components that are needed to realize applications. Firstly, we are separating the variables (the data is not stored, in this case the variable is alive only when I run the program) and those components that allow to store data permanently for us, if we want to manage data in a company, we have to manage them in a permanent way. Here we focus two main ways for storing the data: files or databases (DB). If we talk about technological level, we can see that the different levels are visible and can be seen in different levels of detail as it is shown in the picture.
