Catalog
concept#Architecture#Security#Platform#Reliability

Computer Network

Concept for connecting computers and devices to enable communication and resource sharing. Covers physical media, protocols, topologies and basic security aspects.

A computer network interconnects computers and devices to enable communication and resource sharing.
Established
Medium

Classification

  • Medium
  • Technical
  • Architectural
  • Intermediate

Technical context

Firewalls and VPN gatewaysLoad balancers and proxy systemsCloud connectivity services (e.g. Direct Connect)

Principles & goals

Clear layering and separation of responsibilities.Design for resiliency and redundancy instead of single points of failure.Security and access control as integral parts of the network.
Build
Enterprise, Domain, Team

Use cases & scenarios

Compromises

  • Misconfigurations can disable entire segments.
  • Insufficient segmentation increases attack surface.
  • Single point of failure in central components.
  • Segment by function and sensitivity (VLANs, ACLs).
  • Automated configuration and versioning of network devices.
  • Regular disaster recovery tests and failover verifications.

I/O & resources

  • Topology requirements and capacity planning
  • Hardware (switches, routers, cabling) and IP plans
  • Security policies and compliance requirements
  • Designed and documented network architecture
  • Configured network devices and test runbooks
  • Monitoring and alerting rules

Description

A computer network interconnects computers and devices to enable communication and resource sharing. It comprises physical links, protocols (e.g. TCP/IP), switching and security mechanisms, and topology choices. Networks underpin distributed systems and directly affect latency, availability, and scalability. They guide design decisions across architecture, security, and operations.

✔

  • Enables distributed communication and resource sharing.
  • Scalability through segmented topologies and routing.
  • Centrally manageable security and monitoring controls.

✖

  • Physical and topological limits affect latency and bandwidth.
  • Complexity grows with number of devices and routes.
  • Security risks from misconfigured components.

  • Latency (ms)

    Average response time for packet-based communication between endpoints.

  • Packet loss (%)

    Percentage of packets lost during transmission.

  • Availability (%)

    Percentage of time network services are reachable.

Small company enterprise LAN

Typical implementation with VLAN segmentation, central firewall gateway and internet connectivity via redundant links.

Content Delivery Network (CDN)

Distributed network to reduce latency for end users via geographically distributed caches.

Data center cluster networking

Scalable spine-leaf topology providing high bandwidth and low latency for server-to-server communication.

1

Define requirements and topology, plan addressing.

2

Select hardware and provide base configuration.

3

Implement security rules, run tests and enable monitoring.

⚠️ Technical debt & bottlenecks

  • Outdated firmware on switches and routers without update plan.
  • Incomplete network documentation and IP inventory.
  • Monolithic, non-segmented networks hard to refactor.
Edge link bandwidthRouting table scalingFirewall/load‑balancer capacity
  • Placing production data in test segment without access controls.
  • Exposing public services without firewall or rate-limiting protections.
  • Overreliance on oversized VPN tunnels instead of segmented access control.
  • Underestimating management overhead for distributed topologies.
  • Unconsidered broadcast domains impacting performance.
  • Lack of testing failover scenarios under load.
Networking fundamentals (TCP/IP, VLAN, routing)Knowledge of network security and firewall configurationMonitoring and troubleshooting network issues
Latency requirements for real-time applicationsAvailability and fault toleranceSecurity and compliance requirements
  • • Available physical media and their reach
  • • Budget and operational costs
  • • Regulatory requirements (e.g. data locality)