Aviz Service Node details Diameter GX session state exports via Kafka

Aviz Service Node (ASN) parses and correlates Diameter GX CCR and CCA messages to produce up-to-date subscriber policy session records, including identity, PCC rules, QoS, charging, and session lifecycle context, with exports via Kafka. For mobile core operators, the change targets visibility into what policy and charging data was delivered and how sessions evolved.

Research Overview

The blog describes Diameter GX as the interface used in mobile core networks to carry policy and charging control, connecting the Policy and Charging Rules Function (PCRF) to the Policy and Charging Enforcement Function (PCEF). It explains that PCRF uses CCR and CCA messages to create, modify, and delete policy sessions, with each message carrying policy, charging, QoS, flow, bearer, and access-network information.

Within this context, ASN is presented as a Diameter GX observability component that transforms and correlates signaling data across a subscriber session lifecycle. The blog frames the output as a session record that reflects current state by maintaining and merging session information as Diameter messages are processed.

Key Findings

The blog states that ASN supports up to 3 million concurrent Diameter GX sessions. It also says the latest Diameter GX session state is exported through Kafka keyed by IMSI for downstream analytics and monitoring systems.

It further describes how ASN handles subscriber-session updates using an AVP merge model in a session state, where updated AVPs overwrite prior stored values and newly observed AVPs are added. For cases where multiple sessions exist for the same IMSI, the blog says ASN replaces older sessions with newer ones and initiates priority exports to preserve historical data.

Technical Breakdown

ASN is described as supporting all CCR and CCA message types needed for Gx observability, and as correlating data across the lifecycle of a subscriber session. The blog also identifies exported metadata categories, including subscriber information (IMSI, IMEI, MSISDN), interface and session routing details, and user access context such as RAT type, SGSN/GGSN addresses, and APN.

For policy and enforcement visibility, the blog lists charging rule information (rule base name, rule name, rule type, rating group, charging mode, and flow-related fields), QoS information (including QCI, UL/DL bit rates, priority level, and pre-emption capability and vulnerability), and default bearer QoS parameters. It adds that ASN exports session timestamps and session status fields such as export type and priority cause related to termination and session replace events.

Operational Impact

The blog says operators can validate that PCC rules delivered to the enforcement plane are correctly reflected for subscriber sessions, and verify QoS parameters applied to bearers. It also states ASN tracks charging rule installation and updates across sessions as those changes appear in the Diameter signaling lifecycle.

For day-to-day operations, the blog describes reduced packet-level correlation effort by consolidating CCR/CCA exchanges into a single session record. It also states ASN prioritizes exports for critical state changes such as session termination and session-replace events so that key lifecycle updates are not missed.

The blog’s overall takeaway is that Aviz Service Node turns Diameter GX CCR and CCA signaling into correlated, current subscriber policy session records that include PCC rules, QoS, charging, and lifecycle timing, with exports via Kafka. This “Blog Signals brief” is a fact-based summary of the vendor blog.

Source: aviznetworks.com, by Kishore Chukka.