IS 425

Enterprise Information LECTURE 3

Winter 2006-2007

IS425 Winter 2004-2005 Session 3 2

Agenda

IT architecture & infrastructure (cont.) Exercise reviewing Week 2 materials Risk Management Analysis Primer Software Development / Architecting Security Disaster Recovery

IS425 Winter 2004-2005 Session 3 3

IS425 Winter 2004-2005 Session 3 4

IS425 Winter 2004-2005 Session 3 5

Hot Topics from Week 2 Web 2.0 Storage consolidation –server

virtualization Staffing for PM positions E-commerce Business intelligence (data

mining) Quality assurance IT information management IT staffing with business

knowledge Growing the business Information & data security,

identity management

Disaster recovery Service oriented architecture Portfolio management IT offshore outsourcing and IT

skills Service oriented architecture Regulatory Compliance Reduce architecture

complexity Information and data security Software as service

IS425 Winter 2004-2005 Session 3 6

ExerciseHow 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 infrastructure2. Facilitating and Managing Business Process Redesign3. Developing and managing distributed systems4. Developing and implementing an information architecture5. Planning and managing communication networks6. Improving the effectiveness of software development7. Making effective use of the data resource8. Recruiting and developing IS human resources9. Aligning the IS organization within the enterprise10. Improving IS strategic planning11. Implementing and managing collaborative support systems12. Measuring IS effectiveness and productivity

IS425 Winter 2004-2005 Session 3 7

The Debate

Discussion Forum “Debate Topics”. 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 group’s name.

IS425 Winter 2004-2005 Session 3 8

This Session

Software engineering/architecting is about ensuring that certain thing happen

Security engineering is about ensuring that certain things do NOT happen

IS425 Winter 2004-2005 Session 3 9

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

IS425 Winter 2004-2005 Session 3 10

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

IS425 Winter 2004-2005 Session 3 11

Risk Analysis Steps

IS425 Winter 2004-2005 Session 3 12

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

Software/Application architecture Internal physical structure Problem models to aid developing implementation-independent

models

IS425 Winter 2004-2005 Session 3 13

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.

IS425 Winter 2004-2005 Session 3 14

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

IS425 Winter 2004-2005 Session 3 15

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 forms2. Dynamic forms

3. Encompasses OO and Analysis methodologies

Software Architecting means process of creating software architectures.

IS425 Winter 2004-2005 Session 3 16

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

IS425 Winter 2004-2005 Session 3 17

Software Product Life Cycle

Management View

Software Engineering View

EngineeringDesign View

ArchitecturalView

IS425 Winter 2004-2005 Session 3 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--

IS425 Winter 2004-2005 Session 3 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

IS425 Winter 2004-2005 Session 3 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

IS425 Winter 2004-2005 Session 3 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

IS425 Winter 2004-2005 Session 3 22

Source: Verdon & McGraw: Risk analysis in software design, IEEE Security & Privacy, July 2004

IS425 Winter 2004-2005 Session 3 23

Source: Verdon & McGraw: Risk analysis in software design, IEEE Security & Privacy, July 2004

IS425 Winter 2004-2005 Session 3 24

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?

IS425 Winter 2004-2005 Session 3 25

Security Engineering

Definition == building systems to remain dependable in the face of Malice Error Mischance.

To mitigate, reduce, the effects of threats Unintentional Intentional

IS425 Winter 2004-2005 Session 3 26

Security Threats

IS425 Winter 2004-2005 Session 3 27

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

IS425 Winter 2004-2005 Session 3 28

Source: Verdon & McGraw: Risk analysis in software design, IEEE Security & Privacy, July 2004

IS425 Winter 2004-2005 Session 3 29

What is the appropriate level?

Source: Chokhani: Trusted products evaluation, CACM, july 92

NCSC Guidelines

IS425 Winter 2004-2005 Session 3 30

Source: Chokhani: Trusted products evaluation, CACM, july 92

IS425 Winter 2004-2005 Session 3 31

Security Engineering Tools

Protocols Passwords Access controls Cryptography Distributed Systems Monitoring Systems

IS425 Winter 2004-2005 Session 3 32

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

IS425 Winter 2004-2005 Session 3 33

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

IS425 Winter 2004-2005 Session 3 34

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

IS425 Winter 2004-2005 Session 3 35

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

IS425 Winter 2004-2005 Session 3 36

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?

IS425 Winter 2004-2005 Session 3 37

Quiz Next Week

DL students should download the quiz from COL. Complete the form and then submit it on COL.