Catalog
concept#Security#Architecture#Integration

Network Security

Conceptual overview of measures, architectures, and practices to protect networks, systems, and data.

Network security protects networks, systems, and data from unauthorized access, tampering, and misuse through technical controls, monitoring, and organizational policies.
Established
High

Classification

  • High
  • Technical
  • Architectural
  • Intermediate

Technical context

SIEM and log management systemsIdentity and access management (IAM)Firewalls, routers, and switches

Principles & goals

Prioritize confidentiality, integrity, and availabilityEnforce least privilege and need-to-knowDefense-in-depth via multiple layers of protection
Run
Enterprise, Domain, Team

Use cases & scenarios

Compromises

  • Undetected lateral movement despite perimeter defenses
  • Poorly configured services serving as entry points
  • Outdated firmware or unpatched systems
  • Regular risk and configuration reviews
  • Automated monitoring and alerting
  • Playbooks for common incidents and regular exercises

I/O & resources

  • Network and asset inventory
  • Security policies and compliance requirements
  • Monitoring and log data
  • Rule sets and configuration templates
  • Monitoring and alerting rules
  • Incident response and recovery plans

Description

Network security protects networks, systems, and data from unauthorized access, tampering, and misuse through technical controls, monitoring, and organizational policies. It includes perimeter and host defenses, access controls, encryption, network segmentation, and incident detection and response. The primary goals are confidentiality, integrity, and availability of critical services.

✔

  • Reduced attack surface through segmentation and controls
  • Faster detection and response to security incidents
  • Improved compliance and audit posture

✖

  • Complexity grows with the number of zones and rules
  • Misconfigurations can block legitimate access
  • No absolute protection; residual risks remain

  • Mean Time to Detect (MTTD)

    Average time between incident start and detection.

  • Mean Time to Respond (MTTR)

    Average time to containment and recovery.

  • Percentage of encrypted connections

    Share of network traffic protected by accepted encryption methods.

Firewall deployment in branch networks

Use of stateful firewalls and standardized rule sets to secure branch networks against the Internet.

Zero-trust segmentation in corporate network

Microsegmentation combined with strong authentication for internal services to hinder lateral movement.

VPN architecture for remote work

Central VPN with multi-factor authentication, endpoint assessment, and logging of sensitive access.

1

Inventory, risk assessment, and define objectives.

2

Design: zone model, access controls, and monitoring architecture.

3

Implement: configure firewalls, segmentation, and logging.

4

Test, go-live, and continuous improvement.

⚠️ Technical debt & bottlenecks

  • Old ACLs and complex rules without documentation
  • Outdated security appliances with limited support
  • Lack of automation for configuration checks
Complex rule setsLegacy hardwareLack of visibility
  • Routing all access through a single central device without redundancy
  • Leaving firewall rules open instead of enforcing least-privilege
  • Not collecting and analyzing logs centrally
  • Overestimating effectiveness of single controls
  • Insufficient updates and patch management
  • Ignoring user and operational requirements
Network architecture and routing knowledgeSecurity configuration and incident responseMonitoring, forensics, and log analysis
Availability of critical servicesProtection of sensitive data and workloadsCompliance with regulatory requirements
  • • Heterogeneous network devices and vendors
  • • Operational windows with minimal downtime
  • • Legal and data protection requirements