Campus Network Refresh and Segmentation
Redesigned campus network across 12 buildings with Cisco Catalyst 9000, implementing role-based segmentation and automated provisioning.
Problem
The university operated aging Catalyst 3750/3850 stacks across 12 campus buildings with flat Layer 2 domains spanning entire buildings. Broadcast storms were a recurring issue, there was no segmentation between faculty, student, and IoT device traffic, and new switch deployments required manual configuration that took 2-3 days per closet. The network team needed a modern architecture that could scale to support 15,000+ concurrent devices.
Approach
We designed a routed access campus architecture on Catalyst 9300/9500 with OSPF underlay, segmented traffic into faculty, student, IoT, and guest VRFs, and implemented ISE-based dynamic VLAN assignment. Switch provisioning was automated using Jinja2 templates and a Python-based deployment pipeline that generated configs from a YAML inventory, pushed them to new switches, and ran post-deployment validation checks. The migration was phased building-by-building during scheduled maintenance windows.
Results
- 12 buildings migrated to routed access architecture in 16 weeks
- Broadcast domain size reduced by 95%
- Switch provisioning time reduced from 2-3 days to 45 minutes
- Full traffic segmentation between user roles and IoT devices
- Zero recurring broadcast storm incidents post-migration
Technology Stack
Artifacts Delivered
- Campus network HLD/LLD
- Automated switch provisioning pipeline
- ISE policy configuration and profiling rules
- Building-by-building migration runbooks
- Post-migration validation and performance reports