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VoLTE and VoWiFi Deployment: A Practical Guide for Mobile Operators

Deploying VoLTE and VoWiFi means running voice over IP on the operator's own IMS core and then extending it to Wi-Fi through an ePDG gateway, which securely connects subscribers' devices on untrusted Wi-Fi to the EPC. VoWiFi uses the same IMS infrastructure as VoLTE, so it makes sense to launch VoLTE first and then add VoWiFi. No separate voice core is needed for each access type. The main steps are preparing the IMS and EPC, integrating the ePDG and AAA, configuring SIM cards and devices, and running a pilot before commercial launch.

Lawful Intercept for Mobile and Fixed Networks: Technical Requirements Explained

Lawful interception (LI) is the legally authorized access by law enforcement to the communications of a specific target, carried out by the telecom operator. Technically it comes down to three things: identifying the target's traffic, copying it without the target noticing, and delivering it to the authorities over a defined handover interface. The exact obligations depend on the jurisdiction, so the network design starts from the local legal text, not from the equipment.

Becoming a Convergent Operator: Broadband & MVNO on One Core

A regional broadband provider can add mobile service without building a radio network by launching as an MVNO on a host operator's network. A safe path is to start as a Light MVNO, where the host provides radio, core and SIMs, and move to a Full MVNO with its own packet core, policy and charging once scale justifies it. The main gain of a fixed-mobile bundle is lower churn.

Gone When It Fails? How to Calculate Traffic Accounting Losses in Advance

Traffic accounting discrepancies are discovered late. They surface at the end of the billing period during reconciliation with the billing system, and sometimes only after a subscriber complaint. By then, the logs for the relevant period have already been overwritten and the nodes have restarted. The discrepancy is usually small, around one percent, and it is almost impossible to tie it to a specific event.

Hierarchical QoS on PCEF: How to Manage Service Priorities

A subscriber is downloading a torrent while making a call over a messaging app, but the other person's voice keeps cutting out, and then the call drops. They open YouTube, and the video keeps freezing to buffer. Naturally, the subscriber decides the operator's network is bad, even though the radio link and coverage have nothing to do with it: their own torrent has eaten up all the bandwidth available on their plan.

Scaling in a CUPS Architecture: How to Grow Without Disrupting Subscribers

When scaling the User Plane horizontally, new traffic-processing nodes are added to the cluster. But the entire traffic flow cannot simply be redistributed from scratch. Active sessions must retain their state and continue to be processed on the same node. Therefore, new connections and existing sessions are distributed according to different rules, while active sessions are migrated gradually. In this article, we explain why disruptions occur and how User Plane scaling works when increasing capacity does not come at the expense of inconvenience for individual subscribers.

CUPS for PCEF/PGW: why separate the Control Plane and User Plane in the mobile core

In an operator's network, session control and data transfer grow at different rates. The subscriber base adds a few percent a year, while traffic grows by tens of percent. If both functions live in a single node, they have to be scaled together, forcing the purchase of resources that may not actually be needed.

ePDG Explained: Architecture, IMS Core Integration, and How to Choose a Vendor

An ePDG (Evolved Packet Data Gateway) is the gateway that lets a mobile operator accept subscriber traffic from untrusted Wi-Fi networks and bring it into the EPC through a secure IPsec tunnel. It authenticates the subscriber by SIM and connects the session to the packet core, through which it reaches the IMS core, which is what makes Wi-Fi Calling (VoWiFi) possible. This article covers how an ePDG is built, which interfaces it uses, how it fits with IMS, and what to check when choosing a vendor.

Support for different interface types in the Stingray platform: dpdk_engine=7

As an operator's network evolves, so does its core. It comes to include more and more switches and routers with different interface types, reflecting different stages of infrastructure development.

One server instead of a rack: the new Stingray PCEF processes up to 32 million sessions

VAS Experts' development team has increased the performance of the Stingray PCEF product. After optimization, the solution can process up to 110,000 requests per second while serving 32 million active sessions on a single server.