RAN Controller Tunneling for LTE User Plane Traffic

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In LTE mobile communications networks, there is no existing method to ensure that user plane traffic traverses a RAN controller or cache, which is essential for caching and other applications like cloud hosting or packet inspection, due to the flat RAN architecture without a RAN controller.

Innovation Solution

A method is introduced to establish tunnels between a base station and a Serving Gateway via a node, such as a RAN controller, using tunnelling protocol information to route user plane traffic through the node, and a fallback mechanism is provided in case the node fails.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If LTE flat RAN architecture is used, then network capacity is improved and latency is reduced, but user plane traffic cannot be routed through a RAN controller or cache

Engineering Contradiction:
Improvenetwork latencyVSAvoidtraffic routing flexibility
Core Design Contradiction:
SpeedVSAdaptability or versatility

Solution Approach 1:

The patent segments the user plane traffic path by introducing optional intermediate nodes (RAN controllers, caches) between the base station and serving gateway. This allows the flat architecture to maintain its low-latency benefits while enabling selective routing through segmentation points for caching and other services.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent implements dynamic routing by allowing the network to flexibly select whether user plane traffic traverses through a RAN controller/cache or goes directly to the serving gateway. The routing decision is made dynamically based on service requirements, enabling the system to adapt between direct low-latency paths and routed paths for caching.

Inventive Principle:
Principle #15Dynamics

2Adaptability or versatility

If user plane traffic is routed through a RAN controller for caching, then caching functionality is enabled, but network complexity increases

Engineering Contradiction:
Improvecaching functionalityVSAvoidnetwork architecture complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent segments the user plane path into optional segments that can be inserted for caching functionality. The base station can choose to route traffic through a RAN controller/cache or bypass it, allowing caching to be enabled only when needed without permanently increasing network complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a RAN controller as an intermediary node that can be optionally inserted in the user plane path. This intermediary provides caching and other services when required, but can be bypassed when not needed, thus adding functionality without permanently increasing network complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Adaptability or versatility

If RAN controller is introduced in LTE user plane path, then caching and packet inspection are enabled, but reliability decreases due to single point of failure

Engineering Contradiction:
Improvecaching service capabilityVSAvoidtraffic continuity
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent implements dynamic failover by allowing the base station to switch between routing user plane traffic through a RAN controller/cache or directly to the serving gateway. When the RAN controller fails, the system can dynamically redirect traffic to maintain service continuity, thus reducing the reliability impact of introducing the controller.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent introduces the RAN controller as an optional intermediary that can be bypassed if it becomes unavailable. This intermediary approach allows the network to use caching and inspection services when the controller is operational, but can fall back to direct routing to maintain traffic continuity and reliability.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP2697991B1Sending user plane traffic in a mobile communications network
Publication Date: 2019.12.11 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
  • EP2697991B1 patent drawingFigure 1
  • EP2697991B1 patent drawingFigure 2~4
  • EP2697991B1 patent drawingFigure 5~6

AI summary

A method and apparatus for sending user plane traffic via a node located between a base station and a Serving Gateway in a mobile telecommunications network. The base station receives a message containing tunnelling protocol information identifying the Serving Gateway. It sends a second message towards the node, the second message including tunnelling protocol information identifying the base station and the Serving Gateway. The base station receives a third message from the node, the third message including tunnelling protocol information for the base station to use towards the node, and tunnelling protocol information for the Serving Gateway to use towards the node. A fourth message is sent, which includes tunnelling protocol information for the Serving Gateway to use towards the node. User plane traffic can then be sent between the base station and the Serving Gateway via the node.