SMS Gateways

SMS gateway is a telecommunications network facility for sending or receiving Short Message Service (SMS) transmissions to or from a telecommunications network that supports SMS. Most messages are eventually routed into the mobile phone networks. Many SMS gateways support media conversion from email and other formats.



Different companies developed and use their own communication protocol and most of these protocols are proprietary. For example, Nokia has an SMSC protocol (short message service center) called CIMD (Computer Interface to Message Distribution) whereas another SMSC vendor CMG, has an SMSC protocol called EMI (External Machine Interface).



Two SMSCs cannot connect if they do not support a common SMSC protocol. To deal with this problem, an SMS gateway is placed between two SMSCs. The SMS gateway acts as a relay between the two SMSCs. It translates one SMSC protocol to another one.







Implementations:



Direct-to-mobile gateway appliance

• A direct-to-mobile gateway is a device which has built-in wireless GSM connectivity. It allows SMS text messages to be sent and/or received by email, from web pages or from other software applications by acquiring a Subscriber Identity Module (SIM card).

Direct-to-SMSC gateway

• A direct-to-SMSC gateway is a device which allows SMS text messages to be sent and received by email, from web pages or from other software applications. The gateway connects directly to a mobile operator's SMSC via the Internet or direct leased line connections. It converts the message format into a format understood by the SMSC.

Microsoft Outlook

• Microsoft Outlook 2007 has native support for sending SMS messages worldwide via the Outlook Mobile Service. There is also plug-ins for Microsoft Outlook that adds this functionality.

AOL Instant Messenger

• AOL Instant Messenger (AIM) version 5.2 and above has support for sending SMS messages for free. Third-party client Pidgin also supports this functionality through the AIM protocol.

Yahoo! Messenger

• Yahoo! Messenger, accessible through a dedicated client application or through a web site (mail.yahoo.com) has support for SMS messages. Third-party client Pidgin also supports this functionality through the Yahoo! protocol since version 2.6.

Reference:

http://en.wikipedia.org/wiki/SMS_gateway

http://www.developershome.com/sms/sms_tutorial.asp?page=smsGateway