Computer and Storage Architecture for Investigators

Lesson 11/47 | Study Time: 20 Min

Course: Computer and Cyber Forensics Professional – Course

Computer and storage architecture knowledge empowers investigators in computer and cyber forensics to make smart choices about evidence acquisition, navigate hidden data areas, and anticipate challenges like encryption or wear-leveling. Without grasping how data lives on disks, SSDs, and arrays, you risk missing artifacts or corrupting evidence during imaging.

Disk Fundamentals: HDDs vs. SSDs

Traditional and modern storage differ in how they store and erase data, directly impacting forensics.

1. Hard Disk Drives (HDDs): Spinning platters with read/write heads; data persists magnetically even when "deleted." Logical tools easily image sectors.

2. Solid State Drives (SSDs): NAND flash chips with wear-leveling (randomizes writes) and TRIM (auto-erases deleted blocks), complicating recovery. Over-provisioned areas hide data.

3. Hybrid Drives (SSHDs): SSD cache + HDD bulk storage; forensics requires full imaging to capture both.

Note: HDDs use magnetic platters; SSDs rely on flash memory—knowing this guides safe handling.

Key implication: Power off SSDs quickly—ongoing TRIM destroys evidence.

Partitioning and Volume Management

Devices divide into partitions housing file systems—understanding layouts reveals hidden volumes.

1. Master Boot Record (MBR): Legacy 4-partition limit, 2TB max; stores partition table in first sector.

2. GUID Partition Table (GPT): Modern, 128+ partitions, UEFI boot; resilient to corruption.

3. Dynamic Disks (Windows): Software RAID-like volumes spanning disks.

4. Logical Volume Manager (LVM, Linux): Flexible resizing, snapshots for point-in-time views.

Tools like TestDisk recover lost tables; anomalies signal anti-forensics.

Note: MBR/GPT schemes organize space; investigators check for unallocated or resized partitions.

RAID and Networked Storage

Enterprises cluster drives for redundancy—disassembling requires array awareness.

Note: RAID levels dictate reconstruction; wrong order corrupts data.

Extract RAID metadata pre-dismantling using ddrescue.

File System Layouts Critical for Forensics

File systems organize bits into recoverable structures—parse these for artifacts.

1. NTFS (Windows): Master File Table (MFT) indexes everything; $LogFile tracks changes.

2. FAT32/exFAT: Simple, ubiquitous on USBs; short file names hide data.

3. ext4 (Linux): Journaling prevents corruption; inodes link files to blocks.

4. APFS (macOS): Snapshots, encryption native; containers hold multiple volumes.

Unallocated space and slack (file end to cluster end) hold carved treasures.

Note: Metadata like MACB timestamps (Modified, Accessed, Changed, Born) build timelines.

Encryption and Secure Storage Impact

Modern drives encrypt by default, blocking access without keys.

Note: BitLocker, FileVault, LUKS demand credential forensics first.

1. Full Disk Encryption (FDE): SEDs (self-encrypting drives) tie keys to hardware.

2. Software Wrappers: VeraCrypt volumes mimic free space.

3. Cloud Storage: Transparent encryption; metadata leaks usage patterns.

Workflow: Capture RAM first (keys reside there), then unlock volumes.

Practical Acquisition Strategies by Architecture

Tailor methods to hardware realities.

Note: Live vs. dead acquisition weighs volatility against integrity.

Validate with dual hashes; test on identical hardware setups.

In 2025, NVMe and enterprise SSDs demand high-speed Thunderbolt docks, but principles—know your target—remain timeless for investigators.

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Alexander Cruise

Product Designer

Profile

Class Sessions

1- Evolution of Digital Crime and Cyber Forensics 2- Key Terminology and Scope 3- Digital Evidence Lifecycle and Forensic Principles 4- Legal, Regulatory, and Standards Context 5- Roles and Career Paths in Computer and Cyber Forensics 6- Structured Digital Investigation Methodologies 7- Scoping and Planning an Investigation 8- Evidence Sources in Enterprise Environments 9- Documentation, Case Notes, and Evidence Tracking 10- Working with Multidisciplinary Teams 11- Computer and Storage Architecture for Investigators 12- File System Structures and Artifacts 13- File and Artifact Recovery 14- Common User-Activity Artifacts 15- Principles of Forensically Sound Acquisition 16- Acquisition Strategies 17- Volatile vs Non-Volatile Data Acquisition 18- Handling Encrypted and Locked Systems 19- Evidence Handling, Transport, and Storage 20- Windows Forensics Essentials 21- Linux and Unix-Like System Forensics 22- macOS and Modern Desktop Environments 23- Memory Forensics Concepts 24- Timeline Construction Using OS and Memory Artifacts 25- Network Forensics Fundamentals 26- Enterprise Logging and Telemetry 27- Cloud Forensics (IaaS, PaaS, SaaS) 28- Email and Messaging Investigations 29- Timeline Building from Heterogeneous Logs 30- Modern Malware and Ransomware Landscape 31- Malware Forensics Concepts 32- Host-Level Artifacts of Compromise 33- Ransomware Incident Artifacts 34- Dark Web and Anonymous Network Forensics 35- Common Anti-Forensics Techniques 36- Detection of Anti-Forensics 37- Countering Anti-Forensics 38- Resilient Evidence Collection Strategies 39- Incident Response Frameworks and Phases 40- Forensics-Driven Incident Response 41- Threat Hunting Linked with Forensics 42- Post-Incident Activities 43- Forensic Report Structure 44- Writing for Multiple Audiences 45- Presenting and Defending Findings 46- Ethics, Confidentiality, and Professional Conduct 47- Continuous Learning and Certification Pathways