Glossary of Terms

ASCII (American Standard Code for Information Interchange):
A 7-bit character encoding standard used for English text and basic symbols in SMS messages. Allows up to 160 characters per message.

Data Coding Scheme (DCS):
A parameter in the submit_sm PDU that specifies the encoding format (e.g., ASCII, Unicode, Binary).

ESME (External Short Message Entity):
A non-mobile entity that communicates with an SMSC to send and receive SMS messages (e.g., web applications, email gateways).

GSM (Global System for Mobile Communications):
A standard for mobile networks that SMPP supports for SMS transmission.

iDEN (Integrated Digital Enhanced Network):
A mobile communications technology supported by SMPP v3.4.

Message Centre (MC):
A general term for SMSC or USSD servers that handle storing and forwarding of SMS messages.

Protocol Data Unit (PDU):
The fundamental packet format used in SMPP to exchange commands, responses, and message data between ESME and SMSC.

SMPP (Short Message Peer-to-Peer):
An open, industry-standard protocol for transferring short messages between message centers (SMSC) and SMS applications.

SMSC (Short Message Service Center):
The central component responsible for storing, forwarding, and delivering SMS messages.

TLV (Tag-Length-Value):
A flexible data format used for optional parameters in PDUs, allowing enhanced capabilities without altering the core structure.

Unicode (UCS2):
A 16-bit encoding scheme for multilingual text, allowing the transmission of non-English characters.

Windowing:
A mechanism that allows multiple PDUs to be sent without waiting for individual responses, improving throughput and efficiency.

X.25:
A packet-switched network protocol that SMPP can use for transport layer communication.