GPON deployment checklist for Indian ISPs in 2026
Most GPON rollout guides are written by OLT vendors. They are accurate, comprehensive, and somewhat detached from the realities of an operator running 5,000 to 50,000 subscribers across a Tier-2 Indian city. This is the field version.
Before you order any equipment
1. Confirm your fiber path actually exists. Not on paper. Walk the route. The number of GPON projects delayed by six months because someone discovered a missing duct between the PoP and the first splitter is depressingly high.
2. Decide your split ratio early. 1:64 is the spec; in practice in Indian metros, 1:32 is the sweet spot for subscriber experience versus capex. Going to 1:128 saves fiber but kills your headroom for upgrades.
3. Plan for power. Most Indian PoP failures are power failures, not fiber failures. Spec UPS sizing for 4 hours minimum at full OLT load.
Equipment selection
4. Pick OLTs with a CLI. Sounds obvious. It is not. Some vendors are pushing GUI-only management, and any management platform you adopt will need CLI access. ZTE, Huawei, V-SOL, BDCOM all have proper CLIs.
5. Test your management platform before bulk ordering ONUs. Auto-discovery, profile assignment, VLAN propagation — confirm the platform handles your vendor's quirks. XIMS supports ZTE natively and Huawei-class via generic SSH; other platforms vary.
6. Standardize on one ONU SKU per service tier. Operators end up with seven ONU models because each batch was bought from a different vendor at a different price. Spare-parts management becomes a nightmare.
Network provisioning
7. Set up VLAN templates before the first customer goes live. Trying to retrofit a VLAN scheme onto 500 live subscribers is two weeks of pain.
8. Plan your IP scheme for ten years, not two. RFC1918 is finite. /22 per PoP gives 1,022 hosts. Most operators outgrow /23 within 18 months.
9. Decide CGNAT or public IP per plan. Public IP is a sales differentiator for SOHO; CGNAT is mandatory above scale. Make it a plan attribute from day one.
Operations
10. Set up SNMP polling and trap forwarding on day one. Not month six. A platform like XIMS pulls OLT counters every 60 seconds — knowing an OLT is at 95% CPU before customers complain is what separates good operators from average ones.
11. Test your config backup before you need it. Every OLT, scheduled, versioned. Disaster-recovery drills quarterly.
12. Document your provisioning runbook. New engineers cost two weeks of mistakes without one.
Compliance and billing
13. GST compliance is non-negotiable. Place-of-supply logic, HSN/SAC codes, e-invoicing if you cross the threshold. If your billing software does not handle this natively, you will hand-fix invoices for the rest of your operating life.
14. KYC at activation, not after. TRAI guidelines require it. Operators who provision first and chase paperwork later end up with customers who never produce documents.
What we learned the hard way
The single biggest mistake we have watched ISPs make is treating GPON as "just fiber." It is not. It is a different operations model than wireless, with different failure modes, different escalation paths, different field-engineering skills. Budget for training, not just equipment.
If you want a walk-through of how XIMS handles the OLT provisioning, billing and field-ops side of GPON specifically, book a demo. We'll connect to a real OLT in our lab during the call.