ITEE FE cheat sheet

IT governance assigns decision rights for IT investment; common archetypes are business monarchy, IT monarchy, federal, duopoly, and anarchy.

Portfolio management scores candidate projects on value, risk, cost, and strategic fit; a weighted scoring model makes the ranking explicit and repeatable.

Net present value discounts all cash flows at the required rate; accept projects with NPV above zero, and prefer the highest NPV among mutually exclusive options.

Return on investment equals (benefit minus cost) divided by cost; payback period is the time until cumulative benefit equals cumulative cost.

Risk exposure equals probability of the event multiplied by its monetary impact; mitigation lowers probability, contingency lowers impact.

A RACI matrix assigns each activity exactly one accountable role, with responsible, consulted, and informed roles distributed among stakeholders.

Total cost of ownership sums acquisition, licensing, operations, support, and retirement costs over the asset life, not just the purchase price.

A service level agreement states measurable targets such as availability percentage, response time, and resolution time, plus remedies for misses.

Strategic alignment means IT objectives trace to business objectives; each funded initiative should map to at least one stated business goal.

OSI layers from one to seven are physical, data link, network, transport, session, presentation, and application.

TCP is connection-oriented with sequencing and retransmission; UDP is connectionless with no delivery guarantee and lower overhead.

IPv4 addresses are 32 bits and IPv6 addresses are 128 bits; a subnet mask splits the address into network and host portions.

Common ports: 22 SSH, 25 SMTP, 53 DNS, 80 HTTP, 443 HTTPS, and 3389 RDP.

Symmetric encryption such as AES uses one shared key and is fast; asymmetric encryption such as RSA uses a public and private key pair.

A digital signature is produced by hashing the message and encrypting the hash with the sender's private key, giving integrity and non-repudiation.

RAID 1 mirrors data for redundancy, RAID 5 stripes with single parity and survives one disk failure, RAID 0 stripes with no redundancy.

Virtualization runs multiple isolated guest systems on one physical host through a hypervisor, raising utilization and lowering hardware cost.

The CIA triad defines information security goals: confidentiality limits disclosure, integrity prevents unauthorized change, availability ensures timely access.

The waterfall model proceeds through sequential phases with formal sign-off; changes after a phase completes are costly.

Agile iterations are short fixed timeboxes producing a potentially shippable increment; backlog items are reordered each iteration by value.

Scrum roles are product owner, scrum master, and development team; artifacts are product backlog, sprint backlog, and increment.

Continuous integration merges code to a shared trunk frequently and runs automated build and test on every change.

Continuous delivery keeps the mainline always deployable; continuous deployment additionally releases every passing change automatically.

Test levels run from unit through integration, system, and acceptance; the test pyramid favors many fast unit tests over few slow end-to-end tests.

Version control branching strategies include trunk-based development with short-lived branches and feature branching with longer isolated work.

Infrastructure as code declares target environments in versioned files so provisioning is repeatable and auditable.

Incident management restores service first and investigates root cause after; a post-incident review records cause and preventive actions.