Intro to Networking - Hierarchical Network Topology

Overview

The hierarchical networking model is a strategic design implemented by enterprise and service provider networks for best performance and efficient hardware management at deployment sites. When designing any network, understand two major tenets:

  1. Segmentation - the physical and logical segmentation of network areas for purposes of controlling traffic, through conscious hardware choice and proper device configuration (e.g., VLANs, Port Isolation).
  2. Bandwidth - present and future consideration of downstream and upstream traffic requirements at various points in the network, emphasizing efficiency while avoiding traffic 'bottlenecks' (e.g., Fiber switch core/backhaul, traffic shaping controls).

After designing a purpose-driven network topology, Ubiquiti strongly recommends reviewing product datasheets to ensure that proposed hardware meets the requirements of the intended network. Networking equipment is generally categorized and deployed across 3-4 different hierarchical layers:

  1. Core (also called Aggregation) - ultra-high performance switches and routers located at high-bandwidth traffic areas, primarily concerned with layer-2 packet switching or layer-3 packet routing functions.
  2. Distribution - high performance switches (sometimes routers) located at network areas dealing with vital functions and services (e.g., DNS, Controllers).
  3. Access - switches connecting data devices and users (e.g., Wireless Access Points, Desktops) to the network, commonly with high upstream link and lower bandwidth downstream 
  4. Edge - switches or routers sitting at WAN or MAN boundaries of networks, sometimes as dedicated hardware, or even residing at Distribution/Core layers.
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 Core, Distribution, and Access (as well as Edge) layers comprise the Hierarchical Network Topology.