Modify UE context Request

Description

The Modify UE context Request (MUR) is a Diameter command defined in 3GPP specifications, primarily used in the interaction between the Policy and Charging Rules Function (PCRF) and the Policy and Charging Enforcement Function (PCEF) or the Bearer Binding and Event Reporting Function (BBERF). It operates within the Gx and Gxx reference points. When network conditions change, a subscriber's service profile is updated, or new charging rules need to be applied, the PCRF initiates an MUR command. This command carries updated Policy and Charging Control (PCC) rules, which include parameters like QoS class identifiers (QCIs), allocation and retention priority (ARP), and charging key information. The receiving node (PCEF/BBERF) then enforces these new rules on the corresponding bearer(s), ensuring the UE's session adheres to the updated policy. This mechanism is crucial for implementing dynamic policy control, enabling services like on-the-fly QoS upgrades for video streaming or real-time application of sponsored data plans. The MUR process maintains session continuity while allowing the network to adapt to changing requirements, forming a core part of the 3GPP's policy framework for intelligent traffic management and monetization.

Purpose & Motivation

The MUR command was introduced to address the need for dynamic, mid-session policy modifications within the 3GPP PCC architecture. Prior to its standardization, policy changes often required cumbersome procedures like bearer deactivation and reactivation, or even full session teardown and re-establishment. This was inefficient, caused service interruption, and limited the network's ability to offer real-time, responsive services. The creation of MUR was motivated by the growing demand for sophisticated service differentiation, such as tiered data plans, quality-on-demand offerings, and network-slicing scenarios. It allows operators to instantly apply new business rules or adapt to network congestion without impacting the user experience. Historically, as mobile networks evolved from simple data pipes to service-aware platforms, the ability to modify sessions dynamically became a fundamental requirement for monetization and efficient resource utilization, which MUR fulfills.

Key Features

• Enables dynamic mid-session updates of PCC rules
• Carries updated QoS parameters (e.g., QCI, ARP) for enforcement
• Supports modification of charging rules and charging keys
• Operates over the Diameter-based Gx and Gxx reference points
• Allows for event-triggered policy changes (e.g., location change, quota exhaustion)
• Maintains session continuity during policy application

Evolution Across Releases

Defining Specifications