SMS gateway
Definition
A system that lets software send and receive text messages by connecting apps to mobile carrier networks.
SMS gateway, explained
An SMS gateway is the bridge between an application and the mobile networks that actually deliver text messages. When an app sends you a verification code, it usually does not talk to your carrier directly. Instead it hands the message to a messaging provider or aggregator, which passes it through a gateway into the carrier network using protocols such as SMPP or an HTTP API. The gateway handles routing, formatting and delivery reports, and works in the other direction too, turning incoming texts into data an app can read. Because messages may pass through several companies before reaching your phone, a missing code can be caused by any link in that chain, not just the number you entered. Services that receive codes online, including Noir SMS, rely on this kind of infrastructure to show incoming SMS in a dashboard. Gateways are also where carriers and providers apply spam filtering, registration rules and rate limits, which is one reason legitimate platforms register their messaging traffic and why bulk or abusive sending gets blocked.
Related terms
A2P SMS
Application-to-person messaging: texts sent automatically by software, such as verification codes and alerts.
Delivery receipt
A status report a carrier sends back to the sender saying whether a text was delivered, failed or expired.
Short code
A 5 or 6 digit number that businesses use to send high-volume texts such as verification codes and alerts.
Where you'll meet this term
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