Production-grade OTP authentication with Twilio — SMS, voice, WhatsApp, rate limiting, fraud prevention

Telnyx SMS REST API setup, including A2P 10DLC registration, two-way messaging, bulk SMS integration and testing.

Multi-tenant Twilio communications infrastructure blueprint for SaaS platforms, featuring programmatic subaccount provisioning, A2P 10DLC campaign registration, SMS/Voice webhook normalization, and backoff retries.