Terms and definitions in messaging

Multichannel messaging service is based on a variety of telecommunication and Internet technologies. In the description of services, we often use abbreviations that may not always be known to you. Here we have compiled a glossary of terms and definitions used in the industry.

UDH

User Data Header is a binary sequence that may be present at the start of a short message in SMS. It doesn't contain text, but specifies how the message should be processed. It is a part of the SMS which tells the receiving device what type of message being sent. This is done to ensure correct SMS message delivery.