Catalog
concept#Architecture#Security#Platform#Reliability

Network Design

Structured planning of a network's topology, addressing, capacity and security to satisfy functional and non-functional requirements.

Network design is the structured discipline of planning and specifying a computer network's topology, addressing, capacity, routing and security to meet functional and non-functional requirements.
Established
High

Classification

  • High
  • Technical
  • Architectural
  • Intermediate

Technical context

IPAM and CMDB systemsMonitoring and telemetry platformsAutomation and orchestration tools

Principles & goals

Design with clear layers and responsibilities.Defense-in-depth: implement multiple layers of protection.Plan for scalability and evolution from the start.
Build
Enterprise, Domain, Team

Use cases & scenarios

Compromises

  • Lack of segmentation can lead to widespread security incidents.
  • Insufficient capacity planning causes performance bottlenecks.
  • Incompatible changes by different teams cause outages.
  • Automate configuration and testing early.
  • Use standardized topology and naming conventions.
  • Schedule regular capacity and security reviews.

I/O & resources

  • Business requirements and usage patterns
  • Hardware inventory and existing topology
  • Security and compliance policies
  • Network architecture diagrams
  • Addressing and VLAN plan
  • Rollout and test plans

Description

Network design is the structured discipline of planning and specifying a computer network's topology, addressing, capacity, routing and security to meet functional and non-functional requirements. It covers physical and logical architectures, redundancy, performance and evolution planning. Proper design balances cost, scalability, resilience and operational complexity across technical and organizational contexts.

✔

  • Improved availability and resilience.
  • Predictable performance and capacity planning.
  • Clear security zones and reduced attack surface.

✖

  • Significant planning and coordination effort in heterogeneous environments.
  • Initial costs for redundant hardware and infrastructure.
  • Complexity can increase operational effort if not automated.

  • Latency (ms)

    Measurement of packet transit time between defined endpoints; important for real-time applications.

  • Throughput (Mbps/Gbps)

    Available data rate over critical links; relevant for capacity planning.

  • Availability (%)

    Percentage of time services are available as expected; basis for SLAs.

Campus deployment at University X

Segmentation by faculty, centralized monitoring and redundant core switches to increase resilience.

Hyperscaler connectivity for e-commerce

Direct cloud provider links, dedicated security zones and elastic bandwidth control for peak loads.

Data center modernization at Provider Y

Introduction of a leaf-spine architecture, automated configuration and enhanced telemetry for capacity planning.

1

Gather requirements and involve stakeholders.

2

Evaluate architecture options and document trade-offs.

3

Create detailed designs, addressing and security zones.

4

Implement pilot, test and scale incrementally.

⚠️ Technical debt & bottlenecks

  • Aging hardware in core segments without replacement plan.
  • Manual configuration changes without version control.
  • Fragmented addressing due to short-term patches.
Core switching capacityWAN bandwidthAddressing and IP plan
  • Running all services in a flat network without VLANs.
  • Solving scalability solely by faster hardware.
  • Treating security only as a perimeter firewall.
  • Insufficient documentation leads to misconfigurations.
  • Lack of automation makes rollouts error-prone.
  • Unaccounted dependencies between services.
Network architecture and routing protocolsSecurity and segmentation principlesCapacity planning and performance analysis
Scalability and growth forecastsSecurity and compliance requirementsAvailability and performance SLAs
  • • Budget and procurement cycles
  • • Physical building and cabling constraints
  • • Regulatory requirements and compliance