Metro Fiber Backbone Expansion
A 96-count metro fiber ring linking three central offices — surveyed, spliced, tested, and handed to operations without a single unplanned maintenance window.
Project Overview
Capacity on the east-metro corridor was running hot, and single-homed enterprise customers had no diverse path during fiber cuts. The program added a fully diverse ring across three central offices with hand-off capacity for DWDM growth.
I owned the engineering package end to end: route validation, splice schematics, loss budgets, contractor coordination, and the acceptance test plan signed off by operations.
- •OTDR + OLTS acceptance testing
- •GIS route records & as-builts
- •Zero unplanned outages at cutover
The Challenge
Two offices shared a single physical path along a rail corridor, so one backhoe event could isolate both. Permitting for the diverse route crossed county roads, a canal, and a congested downtown duct bank with almost no spare innerduct.
- Single physical path serving two central offices with no diverse backup for enterprise SLA circuits.
- Downtown duct bank at 90% fill, requiring a pull-through plan that avoided disturbing live cables.
- Cutover windows limited to 12am–4am maintenance slots with full rollback plans required.
Approach & Delivery
1 · Survey & design
Walked every manhole on the proposed route, rodded questionable ducts, and re-routed two segments around collapsed conduit. Produced splice schematics, loss budgets per span, and a phased construction schedule.
2 · Build & test
Coordinated splicing crews across night shifts, witnessed OTDR traces bidirectionally, and rejected two spans that missed the loss budget until they were re-spliced clean.
3 · Migration
Moved enterprise circuits in small batches with per-circuit rollback checkpoints. NOC watched error counters live; every migration completed inside its window.
4 · Handover
Delivered GIS as-builts, updated fiber records, OTDR libraries, and a ring-protection test report. Ran a lunch-and-learn so NOC techs knew the new protection paths by heart.
Outcomes & Deliverables
- Fully diverse ring in service with documented sub-50ms protection switching on every tested path.
- Every span inside its loss budget, with a complete OTDR and light-level test library archived for future troubleshooting.
- GIS as-builts, splice records, and runbooks handed to operations — plus a repeatable acceptance template now used on the next two builds.
Related Work
Planning a fiber build or capacity augment?
I can help with route engineering, loss budgets, and acceptance testing.
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