Information Management

- Goal is splitting complex communication into subtasks

- modern communication is always in layers:

--> Protocol for addressing, for common understandable representation, for operational intent

- Participants perceive communication as "horizontal" --> actually it's vertical except lowest layer

1. Application: which kind of communication takes place? (sending email)

HTTP Hypertext transfer protocol: most used Service on web

-       Transmits websites and content from web server to browser

-       Connection is established for transfer, terminated after completion

SMTP Simple Mail Transfer Protocol: standard mail transfer

-       Protocol used for transmission Port 25

-       Transfers emails between servers (Gmail to GMX)

FTP File Transfer Protocol: transfers files over internet, oldest TCP/IP Service

-       Allows upload and download of files (Port 20 for data, Port 21 for commands)

-       Client/ Server Architecture

Advantage to HTTPs: allows inspection of file trees, no html code needed

2. Host to host: which software is used for communication? (Server)

TCP Transmission Control Protocol: provides complete transmission

- data put into correct order for recipient

- if packets lost --> TCP needs new transmission

UDP User Datagram Protocol: provides incomplete transmission

- Data processed by recipient in order of arrival

- if packets lost --> then it's lost

3. Internet: Which computer is addressed (IP address 10.17.21.1 e.g.)

IP Internet Protocol: establishment, dismantlement of transmission

- Routing (find the way) --> if target not in local network, router forwards traffic to computer in direction of target destination

- Confirmation of receptivity (PING)

4. Network access: How are data transmitted physically (radio link, cable etc.)

- Ethernet

- Token ring

- FDDI

IP Version 4:

-       32 bit

-       Four numbers between 0 to 255 separated by dots: e.g. 216.27.61.137

-       Number of possible addresses: 2^32 = 4.3 Billion ( not enough today)

IP Version 6:

-       128 bit (increases possible addresses to 2^128)

-       Eight blocks of 16 bit each, hexadecimal, separated by colons

-       e.g. 2001:0db8:85a3:08d3:1319:8a2e:0370:7344

Domain Name System/Server: Converts easy-to understand domain names like fhnw.ch (HTTP Requests) into complete IP Address

Hypertext Transfer Protocol Secure HTTPS

- Ensures security of website ( https://)

- Supported encryption method can be used on all internet- enabled computers without other installation

--> Used on sensitive data websites (e-banking)

Transport Layer Security TLS

basis for other protocols (HTTP --> HTTPS)

encrypted and secure communication over internet

-       Prevents interception of connection and manipulation of transmitted data

-       Encryption alone is not sufficient for secure communication

Certificate: Guarantees identity of certificate holder (domain holder)

--> like ID card

certificate is digitally signed so a change is noticeable

Virtual Private network: data transmitting over encrypted connection (secure tunnel)

-       Through tunnel: computer gains access to private network and can access internal resources

-       Connection gets established between VPN Server and VPN client

- Consists of and is assigned to one or more attributes

- Identifies a record of a relation

- Value of a primary should never be changed and cannot be empty (null)

- each attribute can be made the primary key, but it must be unique (artificial attributes like Numbers)

Combined Primary Key: primary key consists of several attributes

--> must be minimal (uniqueness lost when removing any attribute from the table)

--> often consists of secondary key

- attribute related to primary key of another relation (Foreign key)

Relationship:

- relation can contain any number of secondary keys

- primary and secondary key must have same data type (but not same name)

- if no input required for secondary key attribute, it may also be empty (Null values)

- Secondary Keys belonging to primary key may never be empty

- Two tables with 1:1 relation: either take the primary key of first table and add it as secondary key in second table or vice versa

- Primary Key in first table gets placed as secondary key in second table (secondary key is always placed in table with the n!)

- the primary keys of both tables (entity types) become secondary keys and form a new relation together.

e.g. Branches (n) sell Items (m) --> new relation: Sales (Branch No, Item No)

--> In new Relation the secondary keys can become combined primary key

Referential Integrity: prevents database changes from causing secondary key values to reference non-existing records (primary key values)

Is a Relationship type between same entity type --> entities of same type are related (same rules apply as for different entity types)

e.g.

1:1: persons is married to Persons --> Persons (PNo, Name, Firstname, PartnerNo)

1:n: Employee (1) leads Employees (n) --> Employees (ENo, Name, Firstname, SuperiorNo)

n:m: Products/Parts (n) contains Products/Parts (m) --> New Relation: Components (SuperiorNo, SubNo)

Designing a database where redundancies can be avoided

Use:

- detect and eliminate redundancies

- transform existing data into relational model

- create stable and flexiblie data structure that needs to be changed as little as possible

- transforms complex relations n:m into hierarchal relations 1:n

Normalization takes place step-by-step from one normal form to the next

the higher the normal form (1NF, 2NF etc.), the higher the degree of normalization --> meaning less redundancies

To determine the degree of normalization:

relation must be examined: value of each attribute, dependencies between attributes of each relation

Functional Dependency: attribute of A is related to exactly one attribute of B e.g. Persons (PNo, Name, Firstname)

Full Dependency: Attributte B is functionally dependent on all Atrributes in A e.g. Sales (CNo, ANo, Salesdate)

Transitive Dependency: Non-key attribute B is dependent on A and attribute C is functionally dependent on B, But A not functionally dependent on C e.g. Persons (PNo, Name, DepNo, Department)

1NF: if in each table only one value is contained and all atrributes are atomic (indivisble)

2NF: if the relation is in first normal form and every non key attribute is fully functionally dependent on the primary key

3NF: if the relation is in the second normal form and there are no transitive dependencies

Modifications turn the Descriptive model (ERP): business model (current state)

 into..

The Prescriptive model: IT model (traget state)

EM: models digital transformation of an enterprise (Data Model)

-->generates value, promotes business efficiency, agility, durability etc.

Organization view (WHO) : Org. Structure, HR, Hierarchy,

Data view (WHAT): Entity and Data Models (e.g. ER Model)

Control view (HOW): Connects other views to a time-logical schedule (e.g. Process flow diagrams)

Function view (WHERE): Activities within/across business functions (e.g. hierarchy trees)

Product and Service View (WHAT FOR): P&S portfolio (e.g. Product Models)

1. Requirements specification (standards)

2. Data Processing concept

3. Implementation: technical realization

Process: logical sequence of activities (start and termination event)

Business Process: chain of tasks than contribute value for company--> derieved from corporate strategy

- Order-to-Cash (e.g. amazon order): customer submits order, product delivered

- Quote-to-Order: Supplier receives request for purchase quote (purchase order)

- Procure-to-Pay: need for p&s in company--> p&s delivered and payed

- Application-to-Approval (building permit etc): Application for benefit: benefit approved or denied

- Issue-to-Resolution (IT service): customer raises problem/issue --> issue resolved

Activities

- Oversight of Organization Performance --> Manages entire chain of events, activities, decisions

- Improvements (reducing costs, execustion time, error rates

- Tools to design, analyze, execute, monitor business processes

Benefits

- Business-IT alignment: Process Models can be understood by both business and IT people

- Process Improvements: High quality management (cost, time, quality, flexibility), Process automation (workflow, control, efficiency), Business information system integration

1. Initial Ad-Hoc: Enterpreneurial management ( Process known but not documentet)

2. Managed Documentation: Base management (documented process, not modelled)

3. Defined Modelled Process: Process definition (standard processes)

4. Quantitatively Managed: Process measurement (measures with key-figures)

5. Optimizing: Process management, change management (quality feedback and insights from experts)--> very expensive

higher levels: Quality, Productivity

lower levels: risk not meeting customer needs

Purpose:

- Basis for decision making (communicating, analysis)

- Documentation of facts (knowledge, design, automation)

Methods (in control view of ARIS)

- EPC Event-driven Process Chain

- BPMN Business Process Model and Notation

Event driven Process: Mapes start and end state as well as activity, direct graph of function or tasks

1. Events (e.g. order received): does not consume time or money, passive (hexagones)

2. Task function (e.g. check stock): verb plus object, (rectangles with rounded corners)

3. Operators: connector, identify logical links (circle with < and, > and/or, x or)

4. Control flow: temporal, logical dependencies of events and functions

- at least one start and end event --> events followed by event or connector

- functions and events have exactly one incoming and outgoing edge (except start or end event)

- connectors have either several incoming and one outgoing event, or one incoming and several outgoing event

BPMN: for business and IT, simple process notation, Representation by Business Process Diagram

1. Flow Objects: events (circles), activities (rectangles), Gateways/operators  (diamonds)

2. Connecting objects

3. Participants (pool, swimlanes)

Differences to EPC:

- BPD shows how to convert charts into machine readable process descriptions

- has help of workflow engine