Applied Information Technology Engineer ExaminationStudy guide

Covers the basics of sets and propositional logic, radix (n-ary) number systems and floating-point error, probability and statistics including expected value, variance, the normal distribution, and the correlation coefficient, queueing theory (M/M/1) for computing utilization ρ and average waiting time, and optimization via linear programming and the shortest-path problem.

Covers information content, which quantifies how surprising an event is, entropy, the average uncertainty of a source, data compression techniques such as Huffman coding that assign codeword length by frequency, error detection/correction via parity, CRC, and Hamming codes, and character encoding (Unicode/UTF-8, etc.).

Covers the time complexity of basic operations on arrays, lists, stacks, and queues; tree structures (binary search trees, balanced trees, heaps) for hierarchical data; hashing for direct key-to-location lookup; and graphs for relational data—each paired with its time-complexity characteristics.

Covers Big-O notation for evaluating algorithm efficiency as input size grows, binary search and hash-based search, the time complexity and stability of quicksort, merge sort, and heapsort, recursion and the divide-and-conquer technique, dynamic programming for eliminating redundant computation, and graph search (breadth-first / depth-first).

Covers programming-language paradigms and data formats (XML/JSON), machine learning (supervised / unsupervised / reinforcement learning) and deep learning, CNNs used in image recognition, generative AI and LLMs (large language models), and natural language processing for handling human language computationally.

Building on the instruction execution cycle from FE/SG, learn the three categories of pipeline hazards (structural, data, control) and how to address them, superscalar execution (issuing multiple instructions at once), and out-of-order execution (reordering instructions). We also cover the SIMD/MIMD classification of parallel processing via multicore CPUs and GPUs, and calculations for pipeline execution time, MIPS, and CPI.

Building on the FE/SG basics of cache and virtual memory, this section works through effective access time and hit-rate calculations precisely and digs deeper into the performance/reliability tradeoff between write-through and write-back. It also covers virtual memory page replacement algorithms (LRU/FIFO), page-fault calculations, and multi-level cache configurations (L1/L2/L3).

Building on the FE/SG coverage of client-server, three-tier web, and clustering, this section goes deeper into virtualization's core component, the hypervisor (bare-metal vs. hosted), and how it differs from the lighter-weight container approach (e.g., Docker). It also covers load-balancing methods (round robin, least connections), the shared-responsibility split across IaaS/PaaS/SaaS, and redundant configurations (dual system vs. duplex system).

Building on the FE/SG basics of response time/throughput and availability, this section digs deeper into performance estimation via queueing theory (the M/M/1 model, calculating utilization and average wait time), series/parallel/mixed availability calculations, MTBF/MTTR, RASIS, and capacity management thinking.

Building on the FE/SG basics of task management and mutual exclusion, this section goes deeper into comparing scheduling schemes (round robin, priority, SJF), how semaphores implement mutual exclusion, and the four necessary conditions for deadlock and how to avoid it. It also covers the relationship between virtual memory and process management, the role of middleware (DBMS, application servers, message queues), and OSS licenses (GPL, MIT, etc.).

Building on the FE/SG basics of logic circuits and flip-flops, this section digs deeper into the design of combinational circuits (half adders/full adders) and sequential circuits, and reading circuits from truth tables. It also covers practical design decisions for IoT devices (sensors/actuators), the responsiveness of a real-time OS (RTOS), and embedded-specific power-saving design (dynamic voltage and frequency scaling, etc.).

Learn the distinction between UX, which designs the overall experience, and UI, which designs the operable screen; universal design, aiming for usability by everyone, versus accessibility, the reachability of information; lossless compression, which fully restores data, versus lossy compression (JPEG, MPEG), which discards imperceptible information; sampling, quantization, and encoding for digitizing analog information; and VR, which immerses users in a virtual space, versus AR, which overlays information onto reality — with the deeper judgment criteria expected at the Applied Information Technology Engineer level.

Learn to capture data as entities and relationships via E-R diagrams (entity-relationship diagrams), data modeling to translate business requirements into a data model, normalization to eliminate redundancy and update anomalies (first, second, and third normal form, and judging functional dependency at each stage), the primary key that uniquely identifies a row, and the foreign key and referential constraint (referential integrity) that reference another table — including the procedure for deriving a schema from an E-R diagram, at Applied Information Technology Engineer depth.

Learn SQL for manipulating tables (SELECT, JOIN, subqueries, GROUP BY, aggregate functions); the view, a virtual table, and the index, which speeds up searches; the ACID properties of a transaction, a unit of multiple operations; concurrency control (locking, two-phase locking, deadlock) and isolation levels that prevent interference between transactions; log-based failure recovery (rollback, roll-forward); and distributed databases, replication, and NoSQL for spreading data across multiple sites — at Applied Information Technology Engineer depth.

Learn the OSI basic reference model, which layers communication conceptually, and the practical standard TCP/IP; the structure of an IP address and calculating network splits using a subnet mask and CIDR notation; routing, which selects a path; DNS for name resolution and DHCP for automatic IP assignment; protocols such as HTTP/HTTPS, SMTP, POP, and IMAP; calculating transmission time from a line's bit rate (bps); wireless LAN standards and encryption; and SDN and QoS — with an emphasis on calculation problems, at Applied Information Technology Engineer depth.

Building on the CIA triad (confidentiality, integrity, availability) and its complements (authenticity, accountability, non-repudiation), this section covers, at level-3 depth, how key usage differs across symmetric-key, public-key, and hybrid cryptography, the properties of hash functions, digital signatures signed with a private key and verified with a public key, the PKI and certificate authorities (CAs) that guarantee a public key's validity, multi-factor and biometric authentication, and SSL/TLS for securing web communications.

Learn, at level-3 depth: malware (virus/worm/Trojan horse/ransomware), targeted attacks, phishing, and BEC; web application attacks (SQL injection, XSS, CSRF); DoS/DDoS; perimeter defenses (firewall, IDS, IPS, WAF, DMZ); the perimeter-independent zero trust approach; and organizational management via ISMS, risk management, and CSIRT.

Learn, at level-3 depth: the development process (requirements -> external design -> internal design -> programming -> testing); the three pillars of object orientation (encapsulation, inheritance, polymorphism); design visualization with UML (class diagram, use case diagram, sequence diagram); module decomposition metrics (coupling and cohesion); test techniques (white-box testing coverage criteria; black-box testing via equivalence partitioning/boundary value analysis); and review methods.

Learn, at level-3 depth: development models (the waterfall model; agile development via Scrum and XP (Extreme Programming); the spiral model); DevOps, CI/CD, and Infrastructure as Code (IaC); estimation techniques (function point method and COCOMO); and configuration management/version control.

Learn, on the foundation of the PMBOK body of knowledge, scope management via WBS, schedule management via arrow diagrams, PERT, and the critical path (earliest/latest start dates and date arithmetic), cost management via EVM (PV/EV/AC, SV/CV, SPI/CPI, EAC), and the management areas of quality, risk, procurement, and stakeholders, worked as level-3 calculation problems.

Learn, on the foundation of ITIL's service lifecycle/value system, SLA/SLM, incident management, problem management, change management, configuration management, capacity management and availability management (availability calculations using MTBF/MTTR), the service desk, and facility management (UPS/data centers), worked as level-3 calculation and judgment problems.

Learn the audit process (audit planning, execution, reporting, follow-up), audit evidence (sufficiency and appropriateness) and audit techniques (interviews, document review, on-site inspection, CAAT), internal control (IT controls--IT general controls and application controls--and segregation of duties), auditability, and auditor independence.

Learn the IT strategy that realizes management goals and Enterprise Architecture (EA) as the blueprint for organization-wide optimization, together with BPR/BPM and business process modeling that rework the business itself, RPA that automates routine tasks, and DX that transforms the business model. We also cover system planning, requirements definition, external procurement via RFI/RFP/competitive quotation, and solution business (cloud/SaaS adoption), pushing at level 3 into judging the validity of a procurement process itself.

Learn competitive strategy tools that analyze the competitive landscape—SWOT analysis, PPM, Five Forces analysis, value chain, and core competence—as well as marketing (4P, STP) for delivering value to customers, KGI/KPI/CSF and the Balanced Scorecard (BSC) for measuring strategy achievement, and CRM/SCM/ERP that support customers, supply networks, and core operations. At level 3 this tests the integrative skill of combining several analytical frameworks to reach a single management decision.

Learn MOT (management of technology), innovation (open innovation, the valley of death), the technology roadmap, practical AI applications including IoT, machine learning, and generative AI, business systems such as POS and EDI, e-business such as e-commerce, fintech, and the long tail, and JIT/kanban, which eliminate waste in production.

Learn forms of corporate organization, the fundamentals of financial accounting including the income statement, balance sheet, and break-even point (fixed/variable cost), financial indicators such as ROI/ROE, and OR/IE that treat inventory and planning mathematically (inventory management, linear programming, demand forecasting, hypothesis testing, the seven QC tools, decision trees). At level 3 this focuses heavily on calculation and judgment from concrete figures.

Learn intellectual property rights (copyright, industrial property rights), security-related regulations (the Unauthorized Computer Access Law, the Act on the Protection of Personal Information, the Act on Regulation of Information Distribution Platforms), labor and trade regulations (the Worker Dispatch Act, the Act on Proper Subcontracting Transactions), compliance, and standardization (ISO/JIS, de jure standards, de facto standards). At level 3 this emphasizes accurate understanding grounded in current (up-to-date) law and institutions.