core layer
From a network design standpoint: Core Distribution Access
distribution
The core layer is critical for interconnectivity between distribution layer devices, so it is important for the core to be highly available and redundant, so redundancy is the answer.
Policies that adhere to the hierarchical network model design principles typically include segmentation of the network into distinct layers—core, distribution, and access. This structure promotes scalability, reliability, and efficient traffic management by centralizing routing at the core layer, distributing policies at the distribution layer, and managing endpoint access at the access layer. Additionally, these policies often emphasize redundancy and fault tolerance to ensure high availability and performance across the network. Overall, the focus is on clear separation of roles and responsibilities within each layer to optimize network functionality.
Reduced content for bandwidth Increased fault tolerance of the network Simplification of management and troubleshooting
routing between VLANs
core switchesaccess switchesbackbone switchesdistribution switches
core switchesaccess switchesbackbone switchesdistribution switches
Network Systems Administration & Web Graphic Design
A hierarchical network design includes the following three layers:The backbone (core) layer that provides optimal transport between sitesThe distribution layer that provides policy-based connectivityThe local-access layer that provides workgroup/user access to the networkhttp://docwiki.cisco.com/wiki/Internetwork_Design_Guide_--_Internetworking_Design_Basics#Function_of_the_Access_Layer
Hierarchically designed networks can more easily be expanded to suit future needs.Hierarchical design models enhance existing bandwidth through the use of link aggregation.The hierarchical model allows for specialized functionality at each layer, simplifying device management