What is Network Topology?
Network topology refers to the arrangement of network elements, including Splitters, closures, and access terminals, within a communication system. It defines how data flows between connected components and influences network performance, scalability, and reliability.
Key Takeaways
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Definition and Importance: Network topology describes how nodes, links, and devices are arranged in a communication system, directly influencing data flow, performance, and scalability.
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Variety of Topologies: Common types include centralized, zoned, and fabric-based architectures, each suited to different network sizes and operational needs.
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Centralized Topology: This design routes all connections through a central hub, making it easier to manage but potentially less efficient as the network grows.
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Zoned Topology: By distributing resources across zones, this approach enhances scalability and reduces cabling complexity, making it ideal for large-scale data centers.
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Fabric-Based Topology: Using a leaf-spine structure, this topology supports high-speed, low-latency communication with improved redundancy, often used in modern, performance-driven networks.
Types of Network Topologies
Network topologies can be categorized into several types, including centralized, Distributed, and Cascaded architectures. Each topology has distinct advantages depending on the environment, competitive landscape, size, structure, and operational requirements of the network.
Centralized Topology
Centralized Topology is traditionally the network of choice for FTTH deployments in the US and has been predominantly deployed in higher density environments where flexibility in service offering and take rates are required. Offering a single level split architecture and co-locating all of the PON splitters into a single location allows for capex deferral and simplified network upgradability. Centralized Networks are ‘fiber rich’ in the distribution network offering dedicated fiber from the centralized splitter location to the individual premises.
Distributed Topology
Like a centralized topology, distributed networks offer a single level split architecture. However, these splitters are distributed around the deployment area close to the end customer. Significantly reducing fiber requirements in the Distribution network, distributed networks offer a great alternative to Centralized networks for urban to suburban environments.
Cascaded Topology
Cascaded networks vary from Centralized and Distributed architectures by splitting the optical signal into multiple locations within the network. Offering a ‘lean’ network solution providing reduced installation and material requirements. Multiple splitter arrangements provide several options within a cascaded network such as Star, Daisy-chain and Fiber indexing each offering different advantages and should be selected based on the environment, labor requirements and housing density / layout.
Tap Topology
Tap architectures fall under the ‘cascaded’ umbrella as these networks utilize multiple splitters in series, Unlike the cascaded topologies, Optical TAP networks leverage bias / asymmetrical splitters to manage and tap-off part of the optical signal towards the premises with the remaining signal passing on to the next TAP location. This network is extremely lean and is best suited to low density, rural environments.
Applications of Network Topology
Network topology plays a crucial role in Outside plant design, and broadband infrastructure. Choosing the optimal topology for the deployment environment helps reduce both implementation and operational expenses, while also supporting future scalability to ensure the network remains viable for years to come.
