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Network data model

GIS, a network data model is used to represent and study things that are connected like a web — for example, roads, rivers, railway tracks, water pipes, or electric lines.

It focuses on how things are connected and helps us solve problems like finding the best route, the nearest hospital, or where water will flow.


  • Nodes → Points where things meet or end (e.g., road intersections, railway stations, pumping stations).

  • Edges → Lines connecting the nodes (e.g., roads, pipelines, cables).

  • Topology → The "rules" of connection — which node is linked to which edge.

  • Attributes → Extra details about each part (e.g., road speed limit, pipe size, traffic volume).

How It Works 🔍

  1. Make the Network Model

    • Start with a map of lines (roads, pipes, rivers) and mark how they connect.

  2. Run Analyses

    • Routing → Find the shortest or fastest path.

    • Closest Facility → Find the nearest hospital, petrol station, etc.

    • Service Area → Find how far you can travel from a point within a set time/distance.

    • Network Tracing → Follow the path of water, electricity, or goods.

Examples 📌

  • Transport → Plan delivery routes or detours.

  • Utilities → Manage water, gas, or electricity supply.

  • Rivers → Study water flow and flooding risks.

Advantages

  • Models real connections accurately.

  • Can answer complex "how to get there" and "what's connected" questions.

  • Works for many types of networks.



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