Introduction Topic: Application and System Development General security principles The Problem The Controls

Topic: Application and System Development

General security principles

The Problem

The Controls

General Security Principles Accountability Authorization Logging Separation of duties Least privilege Risk reduction Layered defense

Accountability

Authorization

Logging

Separation of duties

Least privilege

Risk reduction

Layered defense

The Initial Problem Access to Information in a Database Release of information Modification of information Denial of service Discretionary vs Mandatory Specific authorization granted and denied Authorization based on assigned classification Relational vs Object Oriented

Access to Information in a Database

Release of information

Modification of information

Denial of service

Discretionary vs Mandatory

Specific authorization granted and denied

Authorization based on assigned classification

Relational vs Object Oriented

Relational Database Tables “ Relation” (Table or set of columns in table) With “Attributes” (Columns) Having “Permissible values” Specific Attribute is “Key” with unique values Occurring in “Instances” (Rows) “ Tuple” of a Relation Instance Views “ Virtual” Relations (tables) With selected “Attributes” Linked by Key attributes

Tables

“ Relation” (Table or set of columns in table)

With “Attributes” (Columns)

Having “Permissible values”

Specific Attribute is “Key” with unique values

Occurring in “Instances” (Rows)

“ Tuple” of a Relation Instance

Views

“ Virtual” Relations (tables)

With selected “Attributes”

Linked by Key attributes

Relational Database Controls Grant/Revoke Privileges by Table, Column, Key set Permissions by View combining specific Tables, Columns, Key sets Conceptually dividing the database into pieces to allow sensitive data to be hidden from unauthorized users Authorizations for specific views having specific attributes, and for actions to perform within those views DAC, by specific grant to user or group by owner MAC, by classification level “ Granularity” - fineness of control permissible in database controls - dependent upon database and implementation

Grant/Revoke Privileges by Table, Column, Key set

Permissions by View combining specific Tables, Columns, Key sets

Conceptually dividing the database into pieces to allow sensitive data to be hidden from unauthorized users

Authorizations for specific views having specific attributes, and for actions to perform within those views

DAC, by specific grant to user or group by owner

MAC, by classification level

“ Granularity” - fineness of control permissible in database controls - dependent upon database and implementation

Relational Database Issues Issues: Verifying access granted - DAC Verifying that View limitations function - MAC Preventing users from creating a copy (becoming “owner”) and granting access to others

Issues:

Verifying access granted - DAC

Verifying that View limitations function - MAC

Preventing users from creating a copy (becoming “owner”) and granting access to others

Object-Oriented Database “ Subjects” “ Objects” “ Methods” of accessing them Controls using Encapsulation, Inheritance, Information hiding “ Granularity” - fineness of control permissible in database controls

“ Subjects”

“ Objects”

“ Methods” of accessing them

Controls using Encapsulation, Inheritance, Information hiding

“ Granularity” - fineness of control permissible in database controls

DAC Object-Oriented Models ORION - Explicit authorization for groups of users to objects based on role Data Hiding (Dr. Elisa Bertino) - Explicit authorization for (groups of) users to objects using “public methods” Control of Function Evaluations (Rafiul Ahad) - Explicit authorization for (groups of) users to execute specific methods Methods Data Hiding (Joel Richardson) - Explicit authorization to execute specific methods determined by the owner

ORION - Explicit authorization for groups of users to objects based on role

Data Hiding (Dr. Elisa Bertino) - Explicit authorization for (groups of) users to objects using “public methods”

Control of Function Evaluations (Rafiul Ahad) - Explicit authorization for (groups of) users to execute specific methods

Methods Data Hiding (Joel Richardson) - Explicit authorization to execute specific methods determined by the owner

DAC Object-Oriented Models - 2 Positive/Negative Authorizations (Dr Eduardo Fernandez) - Explicit positive and negative authorizations View Mechanism (Dr Naftaly Minsky) - Multiple interfaces to objects with a list of laws (rules) governing access

Positive/Negative Authorizations (Dr Eduardo Fernandez) - Explicit positive and negative authorizations

View Mechanism (Dr Naftaly Minsky) - Multiple interfaces to objects with a list of laws (rules) governing access

MAC Object-Oriented Models SORION (Dr Bhavani Thuraisingham) - Assigns security/sensitivity levels to subjects, objects and access methods and regulates access via “properties” based on sensitivity levels Millen-Lunt Model - Assigns sensitivity levels to subjects, objects and access methods and regulates access via axioms and three cases: Data is classified Existence of data is classified Reason for classifying data is classified SODA (Dr Thomas Keefe) - Secure Object-Oriented Database Presented as a standard example Assigns classification levels via inheritance

SORION (Dr Bhavani Thuraisingham) - Assigns security/sensitivity levels to subjects, objects and access methods and regulates access via “properties” based on sensitivity levels

Millen-Lunt Model - Assigns sensitivity levels to subjects, objects and access methods and regulates access via axioms and three cases:

Data is classified

Existence of data is classified

Reason for classifying data is classified

SODA (Dr Thomas Keefe) - Secure Object-Oriented Database

Presented as a standard example

Assigns classification levels via inheritance

Object-Oriented Issues ISSUES Polyinstantiation Producing a more defined version of an object by iteratively replacing variables with other variables or values Information located in more than one location for use by more than one user, usually having different security levels Requires sensitive information to be removed when stored at lower levels Insuring integrity with multiple updates going on is difficult Polymorphism Different objects responding to a common command in different ways

ISSUES

Polyinstantiation

Producing a more defined version of an object by iteratively replacing variables with other variables or values

Information located in more than one location for use by more than one user, usually having different security levels

Requires sensitive information to be removed when stored at lower levels

Insuring integrity with multiple updates going on is difficult

Polymorphism

Different objects responding to a common command in different ways

Programming/Data Attacks Salami attack Data diddling Fraud Logic bomb Mistakes Boundary errors Validation errors Time of Check/Time of Use (serialization) errors Covert channels

Salami attack

Data diddling

Fraud

Logic bomb

Mistakes

Boundary errors

Validation errors

Time of Check/Time of Use (serialization) errors

Covert channels

Database Controls Biggest issue still mistakes, omissions Protection by operating system/platform/db Physical data base integrity Logical data base integrity Element integrity Auditability Access control User authentication Availability Two-phase update (Intent/Commit and Lock) Error detection/correction Integrity with multiple instances (polyinstantiation)

Biggest issue still mistakes, omissions

Protection by operating system/platform/db

Physical data base integrity

Logical data base integrity

Element integrity

Auditability

Access control

User authentication

Availability

Two-phase update (Intent/Commit and Lock)

Error detection/correction

Integrity with multiple instances (polyinstantiation)

Applications Beyond the Database Centralized systems Biggest issue still mistakes, omissions Protection by operating system/platform Physical data base integrity Logical data base integrity Element integrity Database and controlled access links Layers of vulnerabilities Examples and Vulnerabilities

Centralized systems

Biggest issue still mistakes, omissions

Protection by operating system/platform

Physical data base integrity

Logical data base integrity

Element integrity

Database and controlled access links

Layers of vulnerabilities

Examples and Vulnerabilities

Applications Beyond the Database Centralized systems Distributed systems More normal now “ Decentralized” - connected or unconnected but related platforms running independent copies of software with independent copies of data

Centralized systems

Distributed systems

More normal now

“ Decentralized” - connected or unconnected but related platforms running independent copies of software with independent copies of data

Applications Beyond the Database Centralized systems Distributed systems “ Decentralized” - connected or unconnected but related platforms running independent copies of software with independent copies of data “ Dispersed” - interconnected and related platforms running the same software and using the same data, one of which (data or software) is centralized Accommodates change Deploys resources Improves performance Lower risk of system failure due to hardware malfunction

Centralized systems

Distributed systems

“ Decentralized” - connected or unconnected but related platforms running independent copies of software with independent copies of data

“ Dispersed” - interconnected and related platforms running the same software and using the same data, one of which (data or software) is centralized

Accommodates change

Deploys resources

Improves performance

Lower risk of system failure due to hardware malfunction

Applications Beyond the Database Centralized systems Distributed systems “ Decentralized” - connected or unconnected but related platforms running independent copies of software with independent copies of data “ Dispersed” - interconnected and related platforms running the same software and using the same data, one of which (data or software) is centralized “ Interoperable” or “Cooperative” - interconnected platforms running independent copies of software with independent copies of data Combines processing from dissimilar platforms Independently execute/test each component

Centralized systems

Distributed systems

“ Decentralized” - connected or unconnected but related platforms running independent copies of software with independent copies of data

“ Dispersed” - interconnected and related platforms running the same software and using the same data, one of which (data or software) is centralized

“ Interoperable” or “Cooperative” - interconnected platforms running independent copies of software with independent copies of data

Combines processing from dissimilar platforms

Independently execute/test each component

Definitions Loose coupling weak dependencies between modules High cohesion modules perform discrete functions Together, design supporting distributed systems Agent Client/server local link to other areas of system, performs information preparation & exchange for client or server

Loose coupling

weak dependencies between modules

High cohesion

modules perform discrete functions

Together, design supporting distributed systems

Agent

Client/server local link to other areas of system, performs information preparation & exchange for client or server

Potential Vulnerabilities Data problems Aggregation - building new objects from existing objects Inference deriving information not explicit Object reuse/garbage collection - reclaiming information from dynamic storage Data contamination

Data problems

Aggregation - building new objects from existing objects

Inference deriving information not explicit

Object reuse/garbage collection - reclaiming information from dynamic storage

Data contamination

Potential Vulnerabilities Malicious Code Trojan horse - program with hidden and undesirable functions Virus - malicious, usually destructive, code that infects other programs to propagate itself Logic bomb - hidden code designed to perform undesirable activities upon receiving or observing a specific condition Letter bomb - email attachment with malicious code Worm - a program that uses communications methods to propagate itself between systems Applet - platform-independent download-and-run mini-program used in Java programming

Malicious Code

Trojan horse - program with hidden and undesirable functions

Virus - malicious, usually destructive, code that infects other programs to propagate itself

Logic bomb - hidden code designed to perform undesirable activities upon receiving or observing a specific condition

Letter bomb - email attachment with malicious code

Worm - a program that uses communications methods to propagate itself between systems

Applet - platform-independent download-and-run mini-program used in Java programming

Other Definitions Java Sun “platform-independent” programming language Object-oriented, distributed, interpreted ActiveX Microsoft replacement for Java - stripped OLE, designed to run on slow Internet links

Java

Sun “platform-independent” programming language

Object-oriented, distributed, interpreted

ActiveX

Microsoft replacement for Java - stripped OLE, designed to run on slow Internet links

Potential Vulnerabilities Access problems Trap door - secret way in Back door - unapproved method of accessing the system Covert channel - Unapproved communications link between application and another Covert storage channel - Writing to storage through one process, and reading by another (lower security level) Covert timing channel - Processes signal to one another by modulating system use Physical access to the area

Access problems

Trap door - secret way in

Back door - unapproved method of accessing the system

Covert channel - Unapproved communications link between application and another

Covert storage channel - Writing to storage through one process, and reading by another (lower security level)

Covert timing channel - Processes signal to one another by modulating system use

Physical access to the area

Vulnerabilities Summary Spoofing/Eavesdropping Unable to identify/track access/updates Theft of information or hard assets Improper access to information Improper update of information Improper destruction of information Lack of or inadequate data validation Data overwrites Incorrect internal processing Direct data access

Spoofing/Eavesdropping

Unable to identify/track access/updates

Theft of information or hard assets

Improper access to information

Improper update of information

Improper destruction of information

Lack of or inadequate data validation

Data overwrites

Incorrect internal processing

Direct data access

Definitions Data mining Analyzing databases for trends/anomalies using automated tools without knowledge of data Knowledge-base system System to query a collection of knowledge expressed using a formal knowledge representation language Artificial Neural Network Simple processors networked on a uni-directional communications channel that operate on local data and input from the connection able to learn from example and to generalize

Data mining

Analyzing databases for trends/anomalies using automated tools without knowledge of data

Knowledge-base system

System to query a collection of knowledge expressed using a formal knowledge representation language

Artificial Neural Network

Simple processors networked on a uni-directional communications channel that operate on local data and input from the connection

able to learn from example and to generalize

Definitions OLE MS Object Linking & Embedding CORBA Common Object Request Broker Architecture (Object Management Group) Structured Programming Using programming rules and procedures and pre-programmed modules

OLE

MS Object Linking & Embedding

CORBA

Common Object Request Broker Architecture (Object Management Group)

Structured Programming

Using programming rules and procedures and pre-programmed modules

Controls - Personnel Issues Accountability and Risk Reduction Background checks of all personnel Separation of Duties Separate responsibilities for application development, approval, implementation, support

Accountability and Risk Reduction

Background checks of all personnel

Separation of Duties

Separate responsibilities for application development, approval, implementation, support

Application System Development Implement a Systems Development Life Cycle Quality Assurance program Involve QA/QC, Audit, Information Security Enforce review and approval of all applications

Implement a Systems Development Life Cycle

Quality Assurance program

Involve QA/QC, Audit, Information Security

Enforce review and approval of all applications

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance

Systems Development Life Cycle

Applies to new development AND system maintenance

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance Include infosec reviews at each milepost of cycle Verify that security requirements have been met Perform review of design and code

Systems Development Life Cycle

Applies to new development AND system maintenance

Include infosec reviews at each milepost of cycle

Verify that security requirements have been met

Perform review of design and code

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance Include infosec reviews at each milepost of cycle Project Initiation Involve information security in initial discussion of project Perform Risk Assessment to Define sensitivity of information Define criticality of system Define security risks Define level of protection needed Ensure regulatory/legal/privacy issues are addressed Ensure requirements can be met by application

Systems Development Life Cycle

Applies to new development AND system maintenance

Include infosec reviews at each milepost of cycle

Project Initiation

Involve information security in initial discussion of project

Perform Risk Assessment to

Define sensitivity of information

Define criticality of system

Define security risks

Define level of protection needed

Ensure regulatory/legal/privacy issues are addressed

Ensure requirements can be met by application

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance Include infosec reviews at each milepost of cycle Project Initiation Project Definition (Design Analysis) Functional/system design requirements Determine acceptable level of risk Level of loss Percentage of loss Permissible variance Identify security requirements and controls Determine exposure points in process Define controls to mitigate exposure Ensure requirements can be met by application

Systems Development Life Cycle

Applies to new development AND system maintenance

Include infosec reviews at each milepost of cycle

Project Initiation

Project Definition (Design Analysis)

Functional/system design requirements

Determine acceptable level of risk

Level of loss

Percentage of loss

Permissible variance

Identify security requirements and controls

Determine exposure points in process

Define controls to mitigate exposure

Ensure requirements can be met by application

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance Include infosec reviews at each milepost of cycle Project Initiation Project Definition (Design Analysis) System Design (Design Specification) Detailed planning of functional components Design program controls Design security mechanisms Design test plan Design verification Mathematical verification of model and design correspondence

Systems Development Life Cycle

Applies to new development AND system maintenance

Include infosec reviews at each milepost of cycle

Project Initiation

Project Definition (Design Analysis)

System Design (Design Specification)

Detailed planning of functional components

Design program controls

Design security mechanisms

Design test plan

Design verification

Mathematical verification of model and design correspondence

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance Include infosec reviews at each milepost of cycle Project Initiation Project Definition (Design Analysis) System Design (Design Specification) Programming/Training (Software Development) Development personnel should be authorized to work on system Document security Training of support personnel and users

Systems Development Life Cycle

Applies to new development AND system maintenance

Include infosec reviews at each milepost of cycle

Project Initiation

Project Definition (Design Analysis)

System Design (Design Specification)

Programming/Training (Software Development)

Development personnel should be authorized to work on system

Document security

Training of support personnel and users

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance Include infosec reviews at each milepost of cycle Project Initiation Project Definition (Design Analysis) System Design (Design Specification) Programming and Training (Software Development) Installation, Evaluation and Testing Development staff should not conduct evaluation/testing Certification of security functionality Certification of processing integrity Desk check, operational test

Systems Development Life Cycle

Applies to new development AND system maintenance

Include infosec reviews at each milepost of cycle

Project Initiation

Project Definition (Design Analysis)

System Design (Design Specification)

Programming and Training (Software Development)

Installation, Evaluation and Testing

Development staff should not conduct evaluation/testing

Certification of security functionality

Certification of processing integrity

Desk check, operational test

Definitions Acceptance Verification that performance and security requirements have been met Accreditation Formal acceptance of security adequacy, authorization for operation and acceptance of existing risk (QC) Certification Formal testing of security safeguards Operational assurance Verification that a system is operating according to its security requirements Assurance Degree of confidence that the implemented security measures work as intended

Acceptance

Verification that performance and security requirements have been met

Accreditation

Formal acceptance of security adequacy, authorization for operation and acceptance of existing risk (QC)

Certification

Formal testing of security safeguards

Operational assurance

Verification that a system is operating according to its security requirements

Assurance

Degree of confidence that the implemented security measures work as intended

Application System Development Systems Development Life Cycle Applies to new development AND system maintenance Include infosec reviews at each milepost of cycle Project Initiation Project Definition (Design Analysis) System Design (Design Specification) Programming and Training (Software Development) Installation, Evaluation and Testing Destruction

Systems Development Life Cycle

Applies to new development AND system maintenance

Include infosec reviews at each milepost of cycle

Project Initiation

Project Definition (Design Analysis)

System Design (Design Specification)

Programming and Training (Software Development)

Installation, Evaluation and Testing

Destruction

The Real World Systems Development Life Cycle Organizations understaffed, wear too many hats Separation of duties seldom complete Infosec seldom involved in initial stages of development Risks seldom adequately assessed Exposure points and controls seldom adequately determined Code checks are often skimped Approvals are often perfunctory Development process continues without formal approval Few limits on access to program code Change control for programs only

Systems Development Life Cycle

Organizations understaffed, wear too many hats

Separation of duties seldom complete

Infosec seldom involved in initial stages of development

Risks seldom adequately assessed

Exposure points and controls seldom adequately determined

Code checks are often skimped

Approvals are often perfunctory

Development process continues without formal approval

Few limits on access to program code

Change control for programs only

Operational Issues Implementation and Operation Code issues - Change Control Data issues Access Integrity Personnel issues

Implementation and Operation

Code issues - Change Control

Data issues

Access

Integrity

Personnel issues

Controls Implementation and Operation Authorization - All support personnel should be authorized

Implementation and Operation

Authorization -

All support personnel should be authorized

Controls Implementation and Operation All support personnel should be authorized Risk Reduction - All code should be reviewed prior to implementation - Change Management

Implementation and Operation

All support personnel should be authorized

Risk Reduction -

All code should be reviewed prior to implementation - Change Management

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Separation of Duties - Development staff should not review, implement systems

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Separation of Duties -

Development staff should not review, implement systems

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Separation of Duties - Development staff should not review, implement systems Development staff should not support production data

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Separation of Duties -

Development staff should not review, implement systems

Development staff should not support production data

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Separation of Duties - Development staff should not review, implement systems Development staff should not support production data Development staff should not manage security function

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Separation of Duties -

Development staff should not review, implement systems

Development staff should not support production data

Development staff should not manage security function

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Development staff should not review, implement systems Development staff should not support production data Development staff should not manage security function Accountability - Production data should be managed through programs No access should be permitted directly to database

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Development staff should not review, implement systems

Development staff should not support production data

Development staff should not manage security function

Accountability -

Production data should be managed through programs

No access should be permitted directly to database

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Development staff should not review, implement systems Development staff should not support production data Development staff should not manage security function Accountability - No access should be permitted directly to database Production data should be managed by users, not support staff

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Development staff should not review, implement systems

Development staff should not support production data

Development staff should not manage security function

Accountability -

No access should be permitted directly to database

Production data should be managed by users, not support staff

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Development staff should not review, implement systems Development staff should not support production data Development staff should not manage security function Accountability - No access should be permitted directly to database Production data should be managed by users, not support staff All access to production data should be logged

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Development staff should not review, implement systems

Development staff should not support production data

Development staff should not manage security function

Accountability -

No access should be permitted directly to database

Production data should be managed by users, not support staff

All access to production data should be logged

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Development staff should not review, implement systems Development staff should not support production data Development staff should not manage security function No access should be permitted directly to database Production data should be managed by users, not support staff All access to production data should be logged Least Privilege Access control Access should be given to necessary data fields only

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Development staff should not review, implement systems

Development staff should not support production data

Development staff should not manage security function

No access should be permitted directly to database

Production data should be managed by users, not support staff

All access to production data should be logged

Least Privilege

Access control

Access should be given to necessary data fields only

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Development staff should not review, implement systems Development staff should not support production data Development staff should not manage security function No access should be permitted directly to database Production data should be managed by users, not support staff All access to production data should be logged Access should be given to necessary data fields only Layered Defense Access controls should be used in addition to system access

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Development staff should not review, implement systems

Development staff should not support production data

Development staff should not manage security function

No access should be permitted directly to database

Production data should be managed by users, not support staff

All access to production data should be logged

Access should be given to necessary data fields only

Layered Defense

Access controls should be used in addition to system access

Controls Implementation and Operation All support personnel should be authorized All code should be reviewed prior to implementation Development staff should not review, implement systems Development staff should not support production data Development staff should not manage security function No access should be permitted directly to database Production data should be managed by users, not support staff All access to production data should be logged Access should be given to necessary data fields only Access controls should be used in addition to system access Configuration Management

Implementation and Operation

All support personnel should be authorized

All code should be reviewed prior to implementation

Development staff should not review, implement systems

Development staff should not support production data

Development staff should not manage security function

No access should be permitted directly to database

Production data should be managed by users, not support staff

All access to production data should be logged

Access should be given to necessary data fields only

Access controls should be used in addition to system access

Configuration Management

The Real World Implementation and Operation Organizations understaffed, wear too many hats Separation of duties seldom complete Development staff often support production systems IT staff often maintain production data Access is often granted on basis of “least effort”

Implementation and Operation

Organizations understaffed, wear too many hats

Separation of duties seldom complete

Development staff often support production systems

IT staff often maintain production data

Access is often granted on basis of “least effort”

An Example: Y2K Remediation Y2K remediation being done off site 3rd party? Overseas? Background checks?

Y2K remediation being done off site

3rd party?

Overseas?

Background checks?

An Example: Y2K Remediation Y2K remediation being done off site Code returned Reviewed by qualified staff? Gartner estimates at least one $Billion loss due to illicit code in Y2K fixes

Y2K remediation being done off site

Code returned

Reviewed by qualified staff?

Gartner estimates at least one $Billion loss due to illicit code in Y2K fixes

An Example: Y2K Remediation Y2K remediation being done off site Code returned Data corrections being performed by IT remediation staff

Y2K remediation being done off site

Code returned

Data corrections being performed by IT remediation staff

Definitions Loose coupling weak dependencies between modules High cohesion modules perform discrete functions Due Care minimum and customary practice of responsible protection of assets that reflects a community or societal norm Due Diligence prudent management and execution of due care

Loose coupling

weak dependencies between modules

High cohesion

modules perform discrete functions

Due Care

minimum and customary practice of responsible protection of assets that reflects a community or societal norm

Due Diligence

prudent management and execution of due care

Final Considerations What does the development life cycle and change control implementation cover? Applications programs? Supporting libraries? Operating systems? Proportionality

What does the development life cycle and change control implementation cover?

Applications programs?

Supporting libraries?

Operating systems?

Proportionality