Network topology is the physical and logical structure of a network, including layers 2 (L2) and 3 (L3) of the OSI model.

What is Network Topology?

Network topology is the physical and logical arrangement of network elements, including devices, connections, and protocols.

L2 Topology (Layer 2)

Characteristics

  • Switching: MAC-based switching
  • VLANs: Logical segmentation
  • Spanning Tree: Loop prevention
  • Trunking: Trunk links

Devices

  • Switches: Switches
  • Bridges: Bridges
  • Hubs: Hubs
  • Repeaters: Repeaters

Protocols

  • STP: Spanning Tree Protocol
  • RSTP: Rapid Spanning Tree Protocol
  • MSTP: Multiple Spanning Tree Protocol
  • VTP: VLAN Trunking Protocol

L3 Topology (Layer 3)

Characteristics

  • Routing: IP-based routing
  • Subnetting: Division into subnets
  • InterVLAN: Routing between VLANs
  • QoS: Quality of service

Devices

  • Routers: Routers
  • Layer 3 Switches: Layer 3 switches
  • Firewalls: Firewalls
  • Load Balancers: Load balancers

Protocols

  • OSPF: Open Shortest Path First
  • BGP: Border Gateway Protocol
  • RIP: Routing Information Protocol
  • EIGRP: Enhanced Interior Gateway Routing Protocol

Topology Types

Physical

  • Bus: Bus topology
  • Star: Star topology
  • Ring: Ring topology
  • Mesh: Mesh topology

Logical

  • Flat: Flat network
  • Hierarchical: Hierarchical network
  • Hybrid: Hybrid network
  • Virtual: Virtual network

Network Design

Principles

  • Hierarchy: Hierarchical design
  • Redundancy: Redundancy
  • Scalability: Scalability
  • Security: Security

Layers

  • Core: Core layer
  • Distribution: Distribution layer
  • Access: Access layer
  • Edge: Edge layer

Implementation

Phase 1: Analysis

  • Requirements: Requirements analysis
  • Traffic: Traffic analysis
  • Growth: Growth planning
  • Security: Security requirements

Phase 2: Design

  • Architecture: Architecture design
  • Protocols: Protocol selection
  • Devices: Device selection
  • Cabling: Cabling design

Phase 3: Implementation

  • Installation: Device installation
  • Configuration: Device configuration
  • Testing: Connectivity testing
  • Documentation: Network documentation

Phase 4: Operation

  • Monitoring: Network monitoring
  • Maintenance: Network maintenance
  • Optimization: Performance optimization
  • Scalability: Scalability planning

Best Practices

Design

  • Modularity: Modular design
  • Redundancy: Implement redundancy
  • Security: Security by design
  • Documentation: Complete documentation

Implementation

  • Standards: Use standards
  • Testing: Test before implementing
  • Monitoring: Implement monitoring
  • Maintenance: Plan maintenance

Operation

  • Monitoring: Continuous monitoring
  • Maintenance: Regular maintenance
  • Updates: Regular updates
  • Optimization: Continuous optimization

References