Applications & Systems Development A very brief overview of the SDLC and the security issues involved.

Generic Systems Engineering Process  Discover Needs  Define System Requirements  Design System Architecture  Develop Detailed Design  Implement System  Assess Effectiveness of System

System Requirements Software Requirements AnalysisProgram Design CodingTesting Operations & Maintenance A simplistic software development model

System Requirements System Requirements AnalysisDesignCodingTesting Operations & Maintenance The Waterfall development model Going back only one stage limits rework and enhances control

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance A modified Waterfall development model that enforces comparison against specific baselines Validation Verification Unit Testing Verification System Test Revalidation Verification: doing the job right Validation: doing the right job

The Spiral Model

Cost Estimation Models :-) Basic COnstructive COst Model COCOMO –Cost as a function of lines of code Man Months (MM) = 2.4 * 1000s of delivered source instructions Development Schedule = 2.5(MM).38 Function Point Measurement Model –I/O types, internal file types, interfaces, etc Software Life Cycle Model (SLIM) –Manpower buildup index –Productivity factor

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance Security life cycle components Validation Verification Unit Testing Verification System Test Revalidation Info sec policy, standards, legal issues, early validation of concepts

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance Security life cycle components Validation Verification Unit Testing Verification System Test Revalidation Threats, vulnerabilities, sec requirements., reasonable care, due diligence, legal liabilities, cost/benefit, level of protection desired, test plans, validation

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance Security life cycle components Validation Verification Unit Testing Verification System Test Revalidation Incorporating security specs, adjust system & security test plans & data, determine access controls, design docs, evaluate encryption options, verification, business continuity plans

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance Security life cycle components Validation Verification Unit Testing Verification System Test Revalidation Develop security related code, unit testing, reuse other modules if possible, support business continuity plans, docs

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance Security life cycle components Validation Verification Unit Testing Verification System Test Revalidation Integrate security components, test integrated modules per plans, refine docs, conduct security related product verification

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance Security life cycle components Validation Verification Unit Testing Verification System Test Revalidation Install security software, run system conduct acceptance testing, test security software, certify docs & accreditation (if necessary)

System Requirements Software Requirements Product Design CodingIntegration Product Implementa- tion Operations & Maintenance Security life cycle components Validation Verification Unit Testing Verification System Test Revalidation Revalidate security controls, penetration testing, vulnerability analyses, manage change requests, implement change control, make changes, evaluate performance, update docs, recertify

Testing Unit testing Done by separate personnel Check all I/O, modules, files, security, etc

Extreme Programming (XP) Principles Feedback: most useful if it is done rapidly. Assuming simplicity: treating every problem as if it can be solved "extremely simply". Incremental changes: small releases Embracing change: not working against changes but embracing them.

Manifesto for Agile Software Development We are uncovering better ways of developing software by doing it and helping others do it. Through this work we have come to value: –Individuals and interactions over processes and tools –Working software over comprehensive documentation –Customer collaboration over contract negotiation –Responding to change over following a plan That is, while there is value in the items on the right, we value the items on the left more.

Maintenance Phase 1.Request Control Establish request priorities, do Cost estimates User Interface Determine tools to use, determine change effects on other code 2.Change Control Recreate & Analyze the problem Develop changes & tests Quality Control Document changes, & recertify 3.Release Control

Software Capability Maturity Model (CMM) Phase 1: Initiate –Format improvement initiative –Management approval Phase 2: Diagnose –Assess current systems Phase 3: Establish Action Plan Phase 4: Action Phase 5: Leverage –Review changes and process looking for improvements

Object Oriented Systems OO Requirements Analysis OO Aanalysis Domain Analysis OO Design OO Programming Object Request Brokers: CORBA, SOAP

Artificial Intelligence Systems Expert Systems (ES) –algorithm + data structures = Normal Program –Inference engine + knowledge base = ES Blackboards Bayesian Networks Fuzzy logic Neural Networks: weighted inputs to “neurons” yield outputs, “training period” Genetic Algorithms: evolutionary computing, fitness values, cross breeding, mutation

Database Systems Hierarchical Mesh Object Oriented Relational

DB Security Issues Views Granularity Aggregation: –combining higher sensitivity with lower Inference –Users “guessing” higher level values Multiple connections, backups, etc Data warehousing & Mining

Application Controls Service Level Agreements –Turn around time, avg response time, number of users, system utilization rates, up times, transaction volumes, problem resolution Control Types –Preventative –Detective –Corrective

Preventative Controls Accuracy –Data checks, forms, custom screens, validity checks, contingency planning, & backups Security –Firewalls, reference monitors, sensitivity labels, traffic padding, encryption, data classification, one-time passwords, separation of development & testing Consistency –Data dictionary, programming standards & database

Detective Controls Accuracy –Cyclic redundancy checks, structured walk- throughs, hash totals, reasonableness checks Security –Intrusion detection systems, audit trails Consistency –Comparison controls, relationship tests, reconciliation controls

Corrective Controls Accuracy –Backups, control reports, before/after imaging, checkpoint restarts Security –Emergency response & reference monitor Consistency –Program comments & database controls

System Architecture Issues Distributed Systems –Agents, applets, “sandbox,” virtual machines –P2P Centralized –Easier to protect Real Time