IS 425

1
IS 425

• Enterprise Information ILECTURE 3
• Spring 2005

2
Agenda

• Exercise reviewing Week 2 material
• Risk Management Analysis Primer
• Software Development / Architecting
• Security
• Disaster Recovery

3
Hot Topics from Week 2

• CRM
• Delivering shareholder value
• Code of ethics
• Outsourcing
• Security

• Regulatory impact (SOX)
• IT Spending
• Cost Control
• Business Integration
• Employee Retention
• Open Source

4
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?
• Building a responsive IT infrastructure
• Facilitating and Managing Business Process
  Redesign
• Developing and managing distributed systems
• Developing and implementing an information
  architecture
• Planning and managing communication networks
• Improving the effectiveness of software
  development
• Making effective use of the data resource
• Recruiting and developing IS human resources
• Aligning the IS organization within the
  enterprise
• Improving IS strategic planning
• Implementing and managing collaborative support
  systems
• Measuring IS effectiveness and productivity

5
The Debate

• Discussion Forum Debate Topics will open till
  week 4.
• 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 groups name.

6
This Session

• Software engineering/architecting is about
  ensuring that certain thing happen
• Security engineering is about ensuring that
  certain things do NOT happen

7
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

8
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

9
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 lt PC then ignore
• If EL gt PC then investing in PC is
  reasonable

10
Risk Analysis Steps
11
What is the appropriate level
12
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.

13
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

14
Software Development/Architecting

• Software Architecture definitions--
• 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.
• The observable properties of a software system
  (aka the form of the system) including
• Static forms
• Dynamic forms
• Encompasses OO and Analysis methodologies
• Software Architecting means process of creating
  software architectures.

15
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

16
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

17
Software Product Life Cycle
EngineeringDesign View
Management View
Software Engineering View
ArchitecturalView
18
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--

19
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

20
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

21
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

22
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?

23
Security Engineering

• Definition building systems to remain
  dependable in the face of
• Malice
• Error
• Mischance.
• To mitigate, reduce, the effects of threats
• Unintentional
• Intentional

24
Security Threats
25
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

26
Security Engineering Tools

• Protocols
• Passwords
• Access controls
• Cryptography
• Distributed Systems
• Monitoring Systems

27
Encryption Transaction SecuritySecret vs.
Public Key Encryption

• Secret-Key Encryption (single key)
• Symmetric encryption, DES
• Use a shared secret key for encryption and
  decryption
• Key distribution disclosure
• fast, for bulk data encryption

• Public-Key Encryption (Pair of keys)
• Asymmetric encryption, RSA (Rivest, Shamin,
  Adlemann)
• Private/Public keys
• Need digital certificates and trusted 3rd parties
• Slower
• For less demanding applications

28
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

29
Internet security

• Consumers entering highly confidential
  information
• Number of security attacks increasing
• Four requirements of a secure transaction
• Privacy information not read by third party
• Integrity information not compromised or
  altered
• Authentication sender and receiver prove
  identities
• Non-repudiation legally prove message was sent
  and received
• Availability
• Computer systems continually accessible

30
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

31
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?