NAS Message IE Nesting for 5G Protocol Scalability

The patent implements nesting by allowing a first IE to carry a second IE within its structure. The first IE includes a first IEI that identifies the container IE, while the second IE includes a second IEI that identifies the nested IE. This nested structure enables the system to carry additional IE types without requiring new top-level IEIs, effectively extending the IEI space through hierarchical embedding.

The patent transitions from a flat, single-level IE structure to a hierarchical, multi-dimensional structure. By introducing nested IEs where one IE can contain another, the system adds a dimensional layer to the IE organization. This allows the same first IEI to be associated with multiple different second IEIs through the nested relationship, effectively expanding the identifiable IE type space without increasing the number of top-level IEIs.

The patent segments the IE identification task into two independent parts: the first IEI that identifies the container IE structure, and the second IEI that identifies the nested IE content. This segmentation allows each IEI to be independently defined and managed, reducing the complexity of the overall identification system. The first IEI handles the outer layer identification while the second IEI handles the inner layer, creating a modular identification approach.

By introducing the nested IE structure, the patent adds a dimensional layer to IE identification. Instead of requiring a single IEI to identify all possible IE types, the system uses a two-dimensional identification space: the first dimension (first IEI) identifies the container IE, and the second dimension (second IEI) identifies the nested IE. This dimensional expansion allows for more IE types to be identified without increasing the complexity of individual IEI definitions.

The patent uses nesting to increase IE capacity without proportionally increasing protocol structure complexity. By embedding a second IE within a first IE, the system effectively doubles the information capacity of a single IE position in the NAS message. The nested structure allows the first IE to serve as a container that carries both its own identification (first IEI) and the nested IE identification (second IEI), thereby increasing capacity while reusing the existing IEI space.

The first IE structure serves multiple functions: it acts as a container for the second IE, provides its own identification through the first IEI, and enables the nested second IE to be identified through the second IEI. This multi-functionality allows the same first IE structure to carry different types of second IEs (with different second IEIs) without requiring different first IE structures, thereby increasing capacity while maintaining protocol structure simplicity.