Collapsed Core Network Design

A Collapsed Core is when the functions of the Distribution Layer and the Core Layer are implemented by a single device. This type of Network Design is used by Small Scale Enterprises to implement their networks as their network is not large enough, and they might be unable to bear the high cost of the network devices. Therefore, these Enterprises use the Collapsed Core Topology Network Design (2-Tier Hierarchical Network Design) to reduce the network cost while maintaining most of the benefits, functions, and services offered by the 3-Tier Networks.

Network Designing is a process of placing the network devices (currently in use or to be used in the future) in such a manner that it follows all the Structured Engineering Principles which include Hierarchy, Modularity, Resiliency, and Flexibility. This Network Design often depends on the network size and requirements which are a critical factors for the successful implementation of any network.

• Hierarchy: It is a simple yet effective tool in designing networks as it divides/breaks the complex network of devices into small and manageable areas.
• Modularity: Having high modularity means having more modules for various functions in a network which makes a network easier to design and implement.
• Resiliency: It simply means that the designed network must be able to handle both expected and unexpected situations. Expected situations may include normal day-to-day traffic flows or scheduled events for maintenance and Unexpected situations may include hardware or software failures, attacks on the network, and unusual traffic flows (more than desired).
• Flexibility: It means that the network has the ability to be expanded or modified as per the needs and requirements without causing a major change in the network design.

According to the above Structured Engineering Principles, a network design must be based on a Hierarchical model which allows both Flexibility and Resiliency.