Key Takeaways
- Scenario 700 is school-admissions / lottery-portal OTP during the offer window — not exams, homework, bells, or fee cut-off.
- A spare that pairs after offers go live will miss the first-hour spike.
- Student LMS and parent-pay must not steal the admissions radio that week.
- Device caps (2 / 5 / 15) decide whether you can run a hot pair.
- Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Free: 1 device / 300 SMS lifetime / 300 contacts. Developer: 25,000 SMS per year.
Android SMS gateway scenario 700 is an admissions or school-choice lottery. Offers drop at a published instant. Families login OTP to accept a seat before the window closes. Exam and fee-night failovers are the wrong clock: this spike is political, short, and unforgiving.
Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Multi-device · Developer Center. GSMA.
offers live — spare already in pool
Offer-window admissions OTP
Idempotency: accept-session id. Do not double-send because DLR is slow. Cut to spare on heartbeat, last DLR, battery.
If the admissions radio dies in hour one and the spare last paired in March, you will explain empty seats to a board.
Lottery portal vs LMS
| Lane | Clock | Pool | Failover |
|---|---|---|---|
| Admissions OTP | Offer window | Hot pair | Already in pool |
| Student LMS | Term time | Other pool | Must not steal admissions SIMs |
| Offer reminder | T-24 / T-6 | Ops MSISDN | May delay |
Caps: 2 / 5 / 15.
Seventy-two hours
Count last year’s first-hour OTP. Raise OEM ceilings carefully; carrier fair-use still applies. OEM.
Spare before offers drop
Airtime on both SIMs. REST: PHP, C#. MCP wraps REST.
Devices vs lost seats
Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Free: 300 lifetime. Developer: 25,000 SMS per year. Pricing.
Admissions night
Canary T-6h and T-30m. Doze exempt. Setup · Doze.
Applicant PII
Do not log full OTP. Rotate keys. STOP on reminder lanes is not a declined offer.
Email accept only
If you refuse device ops that week, do not offer SMS OTP. CPaaS for that lane if needed.
Checklist
- Admissions OTP ≠ reminder SIM.
- Spare paired and topped up before drop.
- Heartbeat cutover documented.
- T-6h and T-30m canary.
- Idempotent accept-session id.
Next steps
Kill primary at T-20m in staging; prove offer-hour OTP uses spare. Downloads · Docs.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- multi-device and dual SIM routingCapacity and failover
- OTP and 2FA SMS on AndroidAuthentication flows
- SMS delivery reports (DLR)Delivery status tracking
- SMS API documentationLive endpoint reference
