Messaging concepts, explained
Each hub organises one concept: a plain definition, how it works step by step, the key terms with their own answer pages, the regulations that apply, and the guides to read next.
A2P SMS explained
Application-to-person SMS: how business messages are routed, priced and regulated, and how they differ from P2P traffic.
8 key termsExplore the topicSender ID explained
The 'from' identity on an SMS: sender types, country registration and how networks stop spoofed brand names.
11 key termsExplore the topicOTP verification explained
One-time passwords and number verification: channels, a secure flow, fallbacks and the fraud to defend against.
10 key termsExplore the topicSMPP explained
The protocol behind high-volume A2P SMS: binds, submit_sm, windows, delivery receipts and versions.
9 key termsExplore the topicSMS firewall explained
How operators inspect SMS traffic to stop grey routes, SIM boxes, smishing and spoofed senders — and recover A2P revenue.
9 key termsExplore the topicWhatsApp Business API explained
Meta's enterprise WhatsApp product: BSPs, approved templates, the 24-hour window and per-message pricing.
9 key termsExplore the topic