Adaptive Quota Management

Adaptive Quota Management (AQM) dynamically and automatically adjusts the quota size, reservation size, and validity times by actively monitoring balance and quota consumption velocity and thresholds, eliminating erroneous reporting and service denial. AQM optimizes network communication and the accuracy of balance queries and threshold notifications and is self-adjusting for different services, minimizing the need for service-specific configuration.

AQM reduces the signaling load on the main monetization interface between the Packet Gateway (PGW) and the Online Charging System (OCS) in the 4G evolved packet core (EPC), and similarly between the session management function (SMF) and Converged Charging Server (CCS) in the 5G standalone core.

As quota, for example, data megabytes, is requested and granted between the network node (PGW/SMF) and MATRIXX, AQM measures the rate at which a specific session consumes a balance or asset, automatically adjusting the quota sizes and expiration times returned to the network to meet configured business and network requirements. AQM is used to configure and automate timing accuracy curves for each session type, specifying the required average message load for the session and a geometric decay curve. AQM provides accurate, timely usage threshold notifications. As the notification threshold approaches, the quota sizes are efficiently reduced so that all sessions sharing the balance cooperate to hit the threshold. AQM automatically adapts the quota size decisions based on the consumption rates of all involved sessions.

A series of requests for a single service context in an AQM session is called a flow. There can be multiple flows per context and per session. For each flow, the MATRIXX Charging Application dynamically adjusts the size and validity times of reservations and quotas. AQM does not manage non-usage impacts such as subscriber management, recurring grants, and first-usage.

AQM allocates the maximum quota to each flow considering the current quota consumption velocity by the flow against balances, the global quota consumption from all users and devices against balances and the time the asset needs to be available for use. In addition to quota consumption velocity, AQM considers pricing when allocating quota.

AQM optimizes network communication by making reservations and authorizing quota using the following information:
  • Initial Quota Determination (IQD) — The IQD includes an estimated quota and validity time (QVT) for each request for quota, based on the service configuration and on the velocity of quota consumed between earlier requests.
  • Balance Threshold Feedback (BTF) — BTF calculates the available quantity until the next threshold.
Figure 1 shows the general AQM process flow.
Figure 1. AQM Process
AQM Process Diagram
Multiple factors can influence the IQD and BTF:
  • Q/QVT — The quota amount (Q) and duration (QVT) are adjusted as a ratio congruent to velocity, with adjustments performed on both simultaneously. For example, at a velocity of 2 MB per minute, with Q = 10 MB and QVT = 5 minutes drop Q to 1 MB and QVT to 30 seconds if needed.
  • Initial Quota Determination (IQD) — Initial values for Q/QVT are determined from the configuration and historical velocities if known.
  • Balance Threshold Feedback (BTF) — Can decrease Q/QVT based on the distance to threshold and balance consumption of this and other activities.

The following sections describe how these values are determined.