Description
In 3GPP specifications, INFO is a fundamental field name used within protocol data units (PDUs) and information elements (IEs) to encapsulate specific data payloads. It acts as a container or placeholder within message structures defined in technical specifications, such as those for control plane signaling or user plane data transfer. The actual content and format of the INFO field are context-dependent, defined by the specific protocol or procedure in which it is used. For example, in specification 37.462, which covers the LTE Positioning Protocol A (LPPa), INFO fields may carry positioning-related data like measurements or assistance information between the Evolved Node B (eNB) and the Evolved Serving Mobile Location Centre (E-SMLC). The field is designed to be flexible, allowing it to transport diverse data types, including binary data, encoded parameters, or nested structures, as required by the network function. Its usage ensures that protocol messages can be extended or adapted in future releases without redesigning the entire message format, supporting backward compatibility and efficient network evolution. In practice, the INFO field is parsed and interpreted by the receiving entity based on the message type and associated protocol specifications, enabling precise data exchange critical for network operations like mobility management, session management, or service delivery.
Purpose & Motivation
The INFO field exists to provide a standardized and extensible mechanism for carrying variable or complex data within 3GPP protocol messages. In telecommunications networks, protocols must handle diverse information types—from user identifiers to service parameters—without rigid message structures that could limit future enhancements. Before such generic fields, protocols often used fixed formats, making it difficult to introduce new data elements without breaking compatibility. The INFO field addresses this by acting as a flexible container, allowing specifications to define specific content per use case while maintaining a consistent message framework. This design supports the dynamic nature of mobile networks, where new services and features are continuously added across releases. It simplifies protocol design by reducing the need for numerous specialized fields, streamlining implementation, and ensuring that networks can evolve efficiently from Release 8 onward.
Key Features
- Generic data container within protocol messages
- Context-dependent content defined by specific specifications
- Supports flexibility and extensibility in signaling
- Enables backward compatibility across 3GPP releases
- Used in control plane and user plane data exchange
- Facilitates encapsulation of binary or encoded parameters
Evolution Across Releases
Introduced as a basic field name in specification 37.462 for LTE Positioning Protocol A (LPPa), initially used to carry positioning-related information such as measurement data or assistance parameters between eNB and E-SMLC, establishing a flexible container for protocol-specific data.
Defining Specifications
| Specification | Title |
|---|---|
| TS 37.462 | 3GPP TR 37.462 |