Home Public Mobile Network

In the intricate web of mobile communication, the concepts of HPMN and VPMN play a pivotal role, especially in roaming scenarios. Let's delve into the depths of these terms, exploring their significance and implications in the realm of IoT.

Demystifying HPMN and VPMN 

HPMN, or Home Public Mobile Network, represents the native network of a mobile subscriber, where the subscriber holds a subscription. Conversely, VPMN, or Visited Public Mobile Network, denotes the network utilized by a subscriber while roaming outside the geographical coverage area of their HPMN. These networks form the backbone of mobile roaming, enabling seamless connectivity and service access across diverse geographical regions.

The Dynamics of Roaming Scenarios 

Roaming scenarios involve intricate interactions between HPMNs and VPMNs, shaping the flow of communication and financial transactions. Here's a breakdown of the key components involved:

• Originating Leg (OL): The initial segment of a call established between the subscriber and MSC1 within the HPMN.

• Roaming Leg (RL): The intermediary phase of the call journey, spanning from MSC1 in the HPMN to MSC2 in the VPMN, facilitating seamless roaming connectivity.

• Terminating Leg (TL): The final stretch of the call path, linking MSC2 in the VPMN to the roamer, ensuring the successful termination of the call.

Financial Implications of Roaming 

In roaming scenarios, financial transactions occur across multiple legs of the call journey, impacting both the subscriber and the roamer. Here's how the financial burden is distributed:

• Subscriber Charges: The subscriber originating the call within their HPMN incurs charges for the OL segment of the call.

• Roamer Charges: The roamer, situated in the VPMN, bears the financial responsibility for both the RL and TL segments of the call, reflecting the cost of utilizing the visited network's infrastructure.

Summary

The Home Public Mobile Network (HPMN) is the network of an operator in which a mobile subscriber has a subscription. The HPMN is one of the three major actors that mediates in roaming scenarios. A subscriber can remotely use the services of the subscribed network by accessing it through a different network, referred to as the Visited public mobile network (VPMN). The Visited Public Mobile Network is the network used by a mobile subscriber while roaming outside of their Home Public Mobile Network (HPMN). 

When a subscriber in an HPMN calls a roamer in a VPMN, the call is established in three parts or legs: Originating leg (OL) between the subscriber and MSC1, roaming leg (RL) between MSC1 and MSC2 and Terminating leg (TL) between MSC2 and the roamer. The subscriber in this scenario will be charged for the OL, while the roamer will pay for the RL and TL.

The term is used in relation to mobile Roaming which is the ability for a customer of mobile communications to automatically make and receive telephone calls, send and receive data, or access other services while travelling outside the geographical coverage area of the home network, by means of using a network of another operator.

FAQs

• What is the Home Public Mobile Network (HPMN), and how does it relate to mobile subscribers?

  HPMN refers to the primary network of a mobile subscriber, where the subscriber holds an active subscription. It serves as the native network for the subscriber, facilitating access to core mobile services within their designated geographical coverage area.

• How does the Visited Public Mobile Network (VPMN) differ from the Home Public Mobile Network (HPMN)?

  VPMN represents the network utilized by a mobile subscriber while roaming outside the coverage area of their HPMN. Unlike HPMN, which serves as the native network, VPMN provides temporary connectivity and service access to roaming subscribers.

• What role do Originating Leg (OL), Roaming Leg (RL), and Terminating Leg (TL) play in roaming scenarios?

  In roaming scenarios, a call journey consists of three distinct legs: OL, RL, and TL. OL signifies the segment between the subscriber and their home network's MSC, while RL spans the interconnection between the home and visited networks. Finally, TL encompasses the link between the visited network's MSC and the roamer, ensuring seamless call termination.

• How are financial charges distributed in roaming scenarios?

  Financial charges in roaming scenarios are distributed based on the specific segments of the call journey. The subscriber incurs charges for the originating leg (OL), while the roamer bears the financial responsibility for both the roaming leg (RL) and terminating leg (TL), reflecting the utilization of the visited network's infrastructure.