1. IS 425 Enterprise Information I LECTURE 3 Autumn 2004-2005  2004 Norma Sutcliffe

2. IS425 Autumn 2004-2005 Norma Sutcliffe Session 32 This Session Software engineering/architecting is about ensuring that certain thing happen Security engineering is about ensuring that certain things do NOT happen

3. IS425 Autumn 2004-2005 Norma Sutcliffe Session 33 Agenda Exercise reviewing Week 2 material The Debate Risk Management Analysis Primer Software Development / Architecting Security Disaster Recovery

4. IS425 Autumn 2004-2005 Norma Sutcliffe Session 34 Exercise How do you reconcile the issue rankings below from 1996 to the “hot topics” that we discussed last week? What pressures are different and what pressures are the same for the issues and topics? 1. Building a responsive IT infrastructure 2. Facilitating and Managing Business Process Redesign 3. Developing and managing distributed systems 4. Developing and implementing an information architecture 5. Planning and managing communication networks 6. Improving the effectiveness of software development 7. Making effective use of the data resource 8. Recruiting and developing IS human resources 9. Aligning the IS organization within the enterprise 10. Improving IS strategic planning 11. Implementing and managing collaborative support systems 12. Measuring IS effectiveness and productivity

5. IS425 Autumn 2004-2005 Norma Sutcliffe Session 35 The Debate Discussion Forum “Debate Topics” is now open. If you have a topic that you would like to debate – add a message giving a short description of the topic. If you see a topic that interests you particularly – reply to the topic message stating you are interested giving your section number and your name. Discussion forum is open for next two weeks.

6. IS425 Autumn 2004-2005 Norma Sutcliffe Session 36 Risk Management Analysis Primer A process for assessing threats and determining which ones to ignore, reduce, eliminate level of feasible support for efforts to reduce and eliminate Expected Loss = P1 x P2 x L where: P1 = Probability of attack P2 = Probability attack is successful L = loss occurring is attack is successful

7. IS425 Autumn 2004-2005 Norma Sutcliffe Session 37 Risk Management Analysis Primer A process for assessing threats and determining which ones to ignore, reduce, eliminate level of feasible support for efforts to reduce and eliminate by comparing expected losses to prevention costs

8. IS425 Autumn 2004-2005 Norma Sutcliffe Session 38 Risk Management Analysis Primer Expected Loss or EL = P1 x P2 x L where: P1 = Probability of attack P2 = Probability attack is successful L = Loss occurring is attack is successful PC = Prevention costs If EL < PC then ignore If EL > PC then investing in PC is reasonable

9. IS425 Autumn 2004-2005 Norma Sutcliffe Session 39 Risk Analysis Steps

10. IS425 Autumn 2004-2005 Norma Sutcliffe Session 310 What is the appropriate level

11. IS425 Autumn 2004-2005 Norma Sutcliffe Session 311 Software Development/Architecting The design on a system from multiple viewpoints – some common are: Technology stack (physical) view Object (data) view Use (behavioral) view But need to see attributes such as: Modifiability, Build-ability, Security, Reliability, Performance, Business-oriented qualities.

12. IS425 Autumn 2004-2005 Norma Sutcliffe Session 312 Software Development/Architecting The architectural view is a component or subsystem view of the system Module approach where a module is something that can be replaced by another implementation without causing other elements to change. Relatively small amounts of information are exchanged between modules. Modules are loosely coupled Allows concurrent development

13. IS425 Autumn 2004-2005 Norma Sutcliffe Session 313 Software Development/Architecting Software Architecture definitions-- 1. the description of the elements that compose the system, their interactions, the patterns and principles that guide their composition and design, and the constraints on those patterns. 2. The observable properties of a software system (aka the form of the system) including: 1. Static forms 2. Dynamic forms 3. Encompasses OO and Analysis methodologies Software Architecting means process of creating software architectures.

14. IS425 Autumn 2004-2005 Norma Sutcliffe Session 314 Software Development/Architecting VIEWS have PHASES which Distinct – once completed Never Overlap Contain ACTIVITIES which Overlap Repeat Can contain many non-decomposable STEPS Part of problem-specific TASKS

15. IS425 Autumn 2004-2005 Norma Sutcliffe Session 315 Enterprise Architecture Business (process) architecture Business strategy Governance Organization Key business processes (BPs) Information Technology (IT) architecture Software infrastructure supporting BPs Information (Data) architecture Logical and physical data assets Data management resources Application (software) architecture Internal physical structure Problem models to aid developing implementation- independent models

16. IS425 Autumn 2004-2005 Norma Sutcliffe Session 316 Software Product Life Cycle Management View Software Engineering View Engineering Design View Architectural View

17. IS425 Autumn 2004-2005 Norma Sutcliffe Session 317 Management View Phases constitute a development cycle Inception when need identified Gathering or capturing requirements aka specification of requirements Construction when product is implemented (coded), unit tested & system tested When transitioned to users--

18. IS425 Autumn 2004-2005 Norma Sutcliffe Session 318 Software Engineering View Multiple chains of activities running concurrently & overlapping Inputs to activities are “whats” Outputs are “hows” RAS – understand the actual problems Design – transforming reqs into a technically feasible solution I & T – source code D & M – to users

19. IS425 Autumn 2004-2005 Norma Sutcliffe Session 319 Engineering Design View Taken from mechanical engineering Phases are sequential but can be overlapping Information flows from phase to phase PP –problem is defined and req list created CD –problem analyzed and solution concepts created/revised ED –main design or draft design DD –physical arrangement, dimensions and other material properties are specified

20. IS425 Autumn 2004-2005 Norma Sutcliffe Session 320 Architectural View Phases are sequential and milestone driven Product planning and study the entire enterprise context DA- understand completely needs of acquirers and users SD- prepares the architectural-level design DD- refining the architectural description and selecting among alternative designs BP- construct system

21. IS425 Autumn 2004-2005 Norma Sutcliffe Session 321 Pulling It Together If firms are trying to minimize costs why would they embrace “software architecting”? Is there a possible relationship between software architecting and the value chain? Is this type of software architecture prevalent now? What kind of risk analysis can be done on a software development project?

22. IS425 Autumn 2004-2005 Norma Sutcliffe Session 322 Security Engineering Definition == building systems to remain dependable in the face of Malice Error Mischance. To mitigate, reduce, the effects of threats Unintentional Intentional

23. IS425 Autumn 2004-2005 Norma Sutcliffe Session 323 Security Threats

24. IS425 Autumn 2004-2005 Norma Sutcliffe Session 324 General Controls Physical controls Physical design of data center to limit access and protect from elements Access controls Restriction of unauthorized user access to a system Data Security controls Protecting data From disclosure to unauthorized persons From destruction/modification by unauthorized Administrative Controls Issuing guidelines / monitoring compliance Programming Controls Development/Testing standards and procedures Application Controls Inputs/Processing/Output

25. IS425 Autumn 2004-2005 Norma Sutcliffe Session 325 Security Engineering Tools Protocols Passwords Access controls Cryptography Distributed Systems Monitoring Systems

26. IS425 Autumn 2004-2005 Norma Sutcliffe Session 326 Network Protection To protect Internet and E-Commerce Most common security measures are: Access control (PINs) Encryption Cable testers with protocol analyzers Firewall systems that enforce access control between two networks

27. IS425 Autumn 2004-2005 Norma Sutcliffe Session 327 Disaster Recovery Planning Purpose is to keep business running after a disaster. Backups –onsite and offsite Offsite computing arrangements made in advance with hot-site vendors Offsite office arrangement made in advance with cold-site vendors Critical applications identified and recovery procedures addressed Written plan kept in several locations

28. IS425 Autumn 2004-2005 Norma Sutcliffe Session 328 Pulling It Together What kind of aptitude does a security engineer need? What skills does a security engineer need? What kind of aptitude does a software engineer need? What skills does a software architect need? Are they different?