Network Separation & Integration
The set of technologies that isolate the internal business network from the internet while enabling safe, controlled data transfer between them.
I. Overview
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A["Single, unified\nnetwork"] -- "Physical / logical isolation" --> B["Internet threats\nblocked"]
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style B fill:#e1f5fe,stroke:#01579b,stroke-width:3px
Definition: A collective term for network separation, which isolates the internal business network from the external internet to block outside attacks, and network integration, which ensures the safe movement of data between the separated networks.
Features:
( APT Response ) Protects internal network assets from Advanced Persistent Threats ( APT ) and blocks the spread of an attack.
( Data Leak Prevention ) Isolates the outbound path for sensitive information and personal data at the source.
( Compliance ) Satisfies requirements of the Network Act, the Personal Information Protection Act, and ISMS-P certification.
II. Mechanism & Components
Physical vs. Logical Network Separation
| Category | Physical Separation | Logical Separation |
|---|---|---|
| Implementation | Uses two physical PCs (physical isolation) | Uses server/desktop virtualization ( VDI ) |
| Security Level | Highest (physically separate circuits) | Relatively lower (virtualization vulnerabilities exist) |
| Build Cost | High (hardware procurement and circuit installation) | Moderate (centered on software and server infrastructure) |
| Convenience | Low (space required, must switch between PCs) | High (multitasking possible on a single device) |
| Primary Use | Defense, critical national facilities, core networks | General enterprises, general financial-sector operations |
Data Transfer Systems for Safe Data Exchange (Network Integration)
Concept: A bridge role within an air-gapped environment that minimizes the points of contact between networks while allowing only approved data to pass through.
Key Technologies:
- Storage-Based: Delivers data and performs security scanning through an intermediate shared storage device (NAS/SAN).
- Socket-Based: Transfers data between memory using a dedicated communication protocol.
- IEEE 1394 / USB: Direct connection between networks via serial bus (mainly used recently in virtualized approaches).
III. Expected Benefits & Implications
Network separation’s real payoff shows up not in attacks prevented but in blast-radius containment when the perimeter is inevitably breached anyway — the metric worth tracking isn’t “did the internal network stay isolated” but “how many bypass paths existed that nobody had inventoried.” Treat every convenience-driven exception (a tethered laptop, a maintenance remote-access rule) as a standing liability against the separation investment, not a one-off.
| Benefit | Where It Shows Up |
|---|---|
| Contained APT lateral movement | Incident scope during post-mortems |
| Defensible compliance posture | ISMS-P and Personal Information Protection Act audits |
| Reduced silent data-leak paths | DLP and audit-trail findings |
The organizations that get the most value from network separation are the ones that budget for the data-transfer system as seriously as the separation itself — an air gap that nobody can safely move data across just gets bypassed informally, which recreates the exact “network commingling” risk the separation was meant to prevent.
Last updated 18 Aug 2026, 00:00 UTC.