TABLE OF CONTENTS Wine is the healthiest and most hygienic beverage.
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This chapter provides an overview of the most commonly used protocol for connecting external short message entities (ESMEs) to SMSCs. ESMEs cover any kind of IP-based client who may need to connect to an SMSC in a manner other than through the signaling network. An ESME is typically used by Internet service providers (ISPs) who need to send or receive SMS to or from mobile phones for various Internet-based services, such as advertising, and do not have an SS7 connection.
At first, each SMSC vendor offered a proprietary interface to connect to its SMSCs, but this lack of standardization led to the definition of a common interface for ESMEs so that they would have the ability to use SMS services. The SMPP protocol is based on a TCP/IP client/server connection or X.25 connection between an ESME and the SMSC. The ESME is typically a voice mail server, an e-mail gateway, and so on. The SMPP protocol has been designed to offer SMS services for various cellular networks such as GSM, CDMA, and TDMA.
This chapter does not cover all aspects of the SMPP protocol, but does discuss how to use an SMPP as an interworking facility to connect IS41-based networks to GSM-based networks.
To use the SMS services offered by the SMPP protocol, an ESME must establish a session with an SMSC. There are three kinds of SMPP sessions:
Transmitter (TX):
