Collapsed Backbone

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In the dynamic world of networking, the concept of a ‘collapsed backbone’ represents a modern approach to network design, contrasting with traditional multi-tier architectures.

This article delves into the intricacies of collapsed backbones, explaining their structure, functionality, and the benefits they offer in network connectivity. We will explore the working principles of collapsed backbones, how they centralize network connections, and compare them with conventional network designs, providing a comprehensive understanding of this innovative networking methodology.

Table of Contents:

  1. What is a Collapsed Backbone
  2. Working Principle of a Collapsed Backbone
  3. Advantages and Disadvantages of Collapsed Backbone Architecture
  4. Implementation Scenarios
  5. Technological Components
  6. Conclusion
  7. References
Collapsed Backbone architecture

1. What is a Collapsed Backbone?

A collapsed backbone is a network architecture where the backbone and switching components are consolidated into a single, centralized device. This contrasts with traditional network designs where multiple intermediate devices, such as hubs and routers, are used to connect various local area networks (LANs) across different levels or tiers. In a collapsed backbone, the centralization of network connectivity is achieved through high-capacity switches or routers, which handle all the data traffic of the LANs.

For example, in a building, a fiber-optic backbone might run from floor to floor and connect with a hub in a wiring closet on each floor. In contrast, collapsed backbones make use of centralized switches, which provide virtual point-to-point connections for LAN connections; these switches are located in one place. Therefore, instead of having a hub for each floor located in that floor’s wiring closet, a set of stackable Ethernet switches would be located in the wiring closet of a single floor, with individual cables running from this closet to stations in work areas on every floor.

Centralizing the routing in one place, maintenance and troubleshooting is reduced
Centralizing the routing in one place, maintenance and troubleshooting is reduced.

This setup significantly reduces the complexity of the network topology, leading to more streamlined management and maintenance.

2. Working Principle of a Collapsed Backbone

Centralizing Network Connectivity

The fundamental principle behind a collapsed backbone is the centralization of network traffic through a single, robust device. In this setup, all LANs within an organization are directly connected to this central device. This device, typically a powerful switch or router, manages and routes the traffic between different network segments. By centralizing connections, collapsed backbones simplify the network structure, reduce latency, and often improve overall network performance.

Comparison with Traditional Multi-Tier Designs

In contrast to traditional multi-tier network designs, where the network is structured in hierarchical layers with separate devices managing each layer, collapsed backbones eliminate these intermediary layers. Traditional designs often involve separate backbone cables connecting different hubs or switches, which can lead to complexity and increased points of failure. In comparison, a collapsed backbone consolidates these functions into one device, leading to a more efficient and less complex network topology. This simplified design can result in reduced hardware costs and easier network administration.

3. Advantages and Disadvantages of Collapsed Backbone Architecture


The advantages of using a collapsed backbone are that they eliminate the costs of backbone cabling installation, they require fewer devices, their equipment administration is more centralized, and they offer higher available bandwidth for each station.

  • Improved Efficiency: Centralized management results in streamlined data traffic and reduced network complexity.
  • Simplified Management: Fewer devices and simpler topology ease network administration and troubleshooting.
  • Reduced Hardware Requirements: Eliminating multiple intermediate devices leads to cost savings and reduced physical space requirements.

Impact on Network Performance and Scalability

  • Positive impact on performance with reduced latency and bottlenecks.
  • Scalability can be challenging, as expanding the network might require more powerful central equipment.

Drawbacks and Solutions

The disadvantages are that collapsed backbones generally are not feasible for use in more than one building, they require more cabling, they use more expensive devices, and they have a more limited distance capability.

  • Single Point of Failure: Centralization increases risk. Redundancy and robust backup systems can mitigate this.
  • Limited Scalability: Careful planning and investing in high-capacity central devices can address scalability concerns.

4. Implementation Scenarios

Ideal Situations for Deployment

  • Small to Medium-Sized Networks: Where simplicity and cost-effectiveness are priorities.
  • Centralized Business Environments: Offices with centralized operations and data centers.


  • Small Business Networks: Implementing a collapsed backbone for streamlined operations.
  • Educational Institutions: Centralized network system to manage campus-wide connectivity efficiently.

5. Technological Components

Hardware and Software

  • Switches: High-capacity, multi-port switches for handling increased traffic.
  • Routers: Advanced routers for interconnecting different network segments.
  • Management Software: Network management tools for monitoring and maintaining the central system.

Emerging Technologies

  • Cloud-Based Solutions: Integration with cloud services for enhanced functionality.
  • IoT Devices Compatibility: Adapting to IoT trends by ensuring compatibility and security with a range of connected devices.

6. Conclusion

The collapsed backbone architecture represents a significant shift in networking, offering streamlined efficiency, simplified management, and cost-effectiveness, albeit with certain limitations in scalability and potential single points of failure. Adapting to this architecture involves understanding its ideal application scenarios, the necessary technological components, and the emerging trends that might shape its future. As networking continues to evolve, the collapsed backbone remains a viable solution for certain network environments, balancing simplicity and performance.

7. References


  1. Computer Networks” by Andrew S. Tanenbaum: Provides foundational knowledge in computer networking, including network architectures.
  2. Data Communications and Networking” by Behrouz A. Forouzan: Covers various aspects of networking, including detailed discussions on network topologies and designs.
  3. Network Warrior” by Gary A. Donahue: Offers practical insights and real-world scenarios in network setup and management, including backbone architectures.


  1. RFC 1247 – “OSI IS-IS Intra-domain Routing Protocol”: Though focusing on routing protocols, this RFC provides insights into network architecture considerations.
  2. RFC 2328 – “OSPF Version 2”: Useful for understanding the underlying principles of network routing, relevant to backbone network design.