Course Overview

This two-day course will provide attendees with a full overview of the various aspects involved in launching and managing a VoLTE roaming relationship.

Day one will cover the adaptions to the roaming agreement, wholesale and retail charging, and TAP, as well as basic network architecture. Day two will focus on the more technical aspects of the roaming agreement, including SIP signalling, IMS, the IREG test process, and the issues most commonly encountered.

The course will be delivered over Microsoft Teams.

Key Learning Objectives

By the end of the course, attendees will:

  • Understand the VoLTE network architecture and the roaming call flow.
  • Know which amendments to make to the standard roaming agreements and RAEX documents.
  • Understand how VoLTE roaming is included in TAP.
  • Find out how the wholesale and retail model changes compare to legacy roaming.
  • Learn about SIP and IMS.
  • Understand the call flow of the IREG test cases.

Our Industry Experts

The course will be delivered by the following industry experts:

  • Milja Hofman, Roaming Specialist and Owner, Roamingwise
  • Joshua Odoteye, Technical Roaming Specialist, Roamingwise
  • Julia Gullstrand, Head of Roaming and Interconnection, GSMA

Who Should Attend This Course?

This course is suited for anyone involved in either the commercial or the technical aspects of the roaming business, including roaming managers, IREG testers, and TADIG testers.

Course Prerequisites

A basic understanding of the general international roaming processes will be useful.

Course Dates and Times

The course will be delivered over Microsoft Teams on 9 and 10 July 2024, 10:00-12:00 and 13:00-15:00 CET.

Course Completion Certificate

To receive a course completion certificate, registered participants will need to attend the course and complete the course survey.

Course Fee

The course fee is US$1,999.

For group registrations, email [email protected].

Share this course:
Duration: 2 days
Start date: 9 - 10 July 2024
$1,999.00 Per Participant

20% discount available for GSMA Members



Milja Hofman
Roaming Specialist and Owner, Roamingwise

Having twenty-three years of international roaming experience, Milja Hofman started her career with Telfort in The Netherlands as TADIG Tester and Product Manager International Roaming. After spending six years at the Data and Financial Clearing House MACH (now TOMIA) in Luxembourg, Milja started her own company Roamingwise in which she combines her enthusiasm for roaming, and training and consultancy. Her experience makes that Milja has a broad roaming knowledge which she uses in her current trainings and consultancy assignments.

Milja closely follows the GSMA working groups and teaches the GSMA standards. With Roamingwise Milja has supported many satisfied customers in the past thirteen years.



Joshua Odoteye
Technical Roaming Specialist, Roamingwise

Joshua Odoteye is an international telecom consultant with over 14 years’ experience in the telecom industry. His core areas of expertise are international roaming and core networks. He has supervised the implementation, testing and launching of over 300 LTE roaming services as well as several GSM/CAMEL/UMTS services.

Joshua has consulted for various mobile operators across Europe and Africa and has extensively worked on global vendor products including Ericsson, Huawei, Cisco and Nokia.



Julia Gullstrand
Head of Roaming and Interconnection, GSMA

Julia Gullstrand is a telecoms professional with 30 years’ experience in roaming and interconnection starting at UK mobile operator One2One. For the past 20+ years Julia has led the GSMA Working Group dedicated to developing agreement templates and charging models to enable the acceleration and rollout of mobile services worldwide. Julia holds an MBA in Telecoms from the Henley Management College.

For any any queries about our course catalogue, please send us an enquiry