The Segmented or hierarchical mesh topology divides a large Wi-SUN deployment into smaller, regionally managed subnets. Each subnet operates as an independent Wi-SUN network with its own Border Router and routing domain, often connected to a higher-level aggregation layer.

This approach improves manageability, reduces routing complexity, and allows each segment to scale or operate independently while maintaining centralized coordination at higher layers.

Key characteristics

  • Each segment functions as a self-contained Wi-SUN network managed by a dedicated Border Router.

  • Segments can represent geographic regions, logical zones, or operational areas.

  • Segments do not communicate directly over Wi-SUN; instead, Border Routers exchange traffic through the upstream IP network using standard routing or gateway mechanisms.

When to use

Choose the segmented or hierarchical mesh topology if:

  • The deployment covers large geographic areas or multiple administrative zones.

  • Operational separation between teams or regions is required.

  • You need to reduce routing table size and limit broadcast domains.

  • Fault isolation between network segments is desirable.

Suitable for city-wide or industrial deployments where interconnections occur only through a central management layer.

Pros and cons

  • Pros

    • Simplifies routing and management within each region.

    • Reduces mesh convergence time by limiting the size of each routing domain.

    • Enables independent maintenance or upgrades in each segment.

    • Provides fault isolation—failures in one subnet do not affect others.

  • Cons

    • Requires inter-segment routing or tunneling to enable communication between areas.

    • Adds complexity to centralized monitoring and coordination.

    • Requires consistent configuration across Border Routers to maintain interoperability.

Considerations

Segmented or hierarchical mesh deployments present these requirements:

  • Inter-segment routing: Define clear IP boundaries and routing policies between segments.

  • Coordination: Use a central management platform (such as Digi Remote Manager) to maintain configuration consistency.

  • Scaling strategy: Plan prefix allocation and addressing per segment to prevent overlaps.

  • Performance: Keep segment size balanced—too small increases management overhead, too large affects stability.