SMS gateways solve a common telecommunications problem, that of different wireless telephony providers using different or proprietary communication protocols. The gateway acts as a relay, translating one protocol into another. Wireless network operators use SMS gateways to connect SMS centers (SMSCs). An SMSC is the portion of a wireless network that handles SMS operations, such as routing, forwarding and storing incoming text messages on their way to desired endpoints.

Along with many commercial software products, open source SMS gateway software can be downloaded online. Kannel, written in C, can make connections to SMSCs, cellular phones and GSM or GPRS modems. Kannel uses an HTTP / HTTPS interface for sending and receiving SMS messages.

Read more about it:
>>	Developershome.com has an SMS tutorial that explains more about how SMS gateways work.
>>	Developershome.com also provides a handy comparison of SMS service providers, including SMS gateway providers, SMS resellers and SMS brokers.
>>	Wikipedia's entry for SMS gateway includes a listing of many of the relevant URLs for the correct email addresses for different telephony providers.
>>	GFI Software makes the business case for SMS gateways.
>>	The Development Seed blog explains how they used an SMS gateway to order beer with SMS.
>>	Kannel is an open source SMS gateway software package.