Telecom Services, Customer Premises and Billing
This domain tests what the customer buys, the equipment at the premises, and how usage becomes a correct invoice. It covers service types, the demarcation point, ONT and router configuration, and tariff and tax arithmetic.
Core rules
- Services include PSTN voice, VoIP, broadband/FTTH, leased lines, IPTV, VPN and mobile.
- CPE includes the ONT, router, set-top box and IP phone. The demarcation point separates operator responsibility from customer responsibility.
- Wi-Fi setup covers SSID, WPA2/WPA3 security and changing the default admin password.
- Billing is prepaid or postpaid; CDRs record usage; an invoice shows plan, period, usage, rental, tax and total.
- Provisioning requires KYC; complaints and disputes need a ticket reference and clear timelines.
Worked example
A plan at ₹599 includes 100 GB, with extra data at ₹10/GB. The customer uses 112 GB: 12 GB × ₹10 = ₹120. Subtotal is ₹599 + ₹120 = ₹719. GST at 18% is ₹129.42. Total is ₹848.42. If the plan says taxes included, the ₹719 is the final bill and GST is extracted backwards, not added.
Traps
Adding GST twice; mixing Mbps with MB/s; switching between 1000 and 1024 MB per GB without following the given convention; billing an activation fee as monthly rental; assuming CPE is always operator-owned; ignoring prorated first-month charges.