RAN Node Context Management for Fast Small Data Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The mechanisms for delivering NAS PDU between the new NG-RAN and the last serving NG-RAN are not defined, posing a challenge for fast small data transmission in wireless communication systems.
Innovation Solution
A method where the last serving RAN node suspends the RRC connection with a wireless device, receives AS-Release Assistance Information from the new RAN node, and decides whether UE context relocation is required based on this information, then transmits an RRC message to the new RAN node accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If UE context relocation is performed for every small data transmission, then data transmission can be maintained, but signaling overhead and network complexity increase
Solution Approach 1:
The patent applies local quality by differentiating the treatment of UE context based on the specific transmission scenario. Instead of uniformly relocating UE context for all small data transmissions, the system evaluates whether relocation is actually needed based on local conditions such as whether the UE is in RRC inactive state and whether the data can be transmitted via the current serving RAN node. This selective approach reduces unnecessary context relocation while maintaining transmission reliability where needed.
Solution Approach 2:
The patent implements preliminary action by having the UE provide AS-Release Assistance Information before the actual data transmission occurs. This information includes indicators about whether the UE has uplink data to send and whether it can be transmitted in RRC inactive state. By having this information prepared in advance, the network can make informed decisions about whether context relocation is necessary, avoiding unnecessary relocation operations while ensuring transmission continuity.
2Productivity
If RRC connection is suspended to enable fast small data transmission, then transmission speed improves, but loss of information about subsequent data transmission requirements occurs
Solution Approach 1:
The patent applies preliminary action by collecting AS-Release Assistance Information from the UE before suspending the RRC connection. This information includes critical data about whether the UE has subsequent uplink or downlink data transmission requirements. By gathering this information in advance, the system can make informed decisions about context relocation while maintaining fast transmission capabilities, thus preventing information loss that would otherwise occur after connection suspension.
Solution Approach 2:
The patent implements feedback mechanisms where the UE provides AS-Release Assistance Information to the last serving RAN node about its data transmission status and requirements. This feedback loop allows the network to maintain awareness of the UE's data transmission needs even after RRC connection suspension, enabling appropriate context relocation decisions while preserving the fast small data transmission capability.
Data Source
AI summary
A method and apparatus for fast small data transmission in a wireless communication system is provided. A last serving RAN node receives, from the wireless device and via a new RAN node, an AS-RAI related to early data transmission. A last serving RAN node decides whether a UE context relocation to the new RAN node for the wireless device is required or not based on the received AS-RAI. A last serving RAN node transmits, to the new RAN node, an RRC message based on the decision.