Switching and VLANs
Calculated locally
STP Port Role Visualizer
Evaluate a simple L2 topology and recalculate designated and alternate roles based on path costs.
Learn before you deploy
Reference PacketToolbox learning content related to this workflow.
Tool input
Use the fields below and run the calculation or generation locally.
Results
Review output and validation notes before production use.
How it works
Adjust per-link costs and root selection to see role changes.
All processing runs in-browser with no external API dependency.
Practical example
Example: Lowering one link cost can move a root-port decision to a new path.
Related tools
Use these together for complete design and troubleshooting workflows.
- IPv4 Subnet Calculator for subnet boundary and wildcard checks.
- VLSM Planner for hierarchical IPv4 allocation.
- Route Summarization Calculator for clean route advertisement planning.
- Cisco ACL Builder for policy-generation workflows.