Roaming with Voice in LTE networks

Mats Lindberg, Business Solutions Director, Polystar Group

This post is by Mats Lindberg, Business Solutions Director, Polystar Group.

Roaming is a fundamental part of the mobile telecoms customer experience and it is essential to support it in every generation of technology. LTE has been introduced on all continents already and will be gradually rolled throughout all networks. LTE provides cost-effective and fast multimedia mobile data services and helps drive value through an improved subscriber quality of experience.

As subscribers roam between the LTE and GSM/UMTS networks, operators ensure continuity of the voice service with minimal service disruptions. However, international roaming capability for the next generation mobile services still remains a big challenge.

We believe LTE roaming will contribute to the success of LTE, irrespectively of hard pressure from different governments and EU with regards to tariffs, cap of traffic/cost, notification of usage etc.

Another issue concerning data roaming, in particular LTE roaming, is that OTT applications add to the roaming business case instead of being a threat to traditional voice services, which is normally the case when looking at the business case for the home market. Due to the importance of roaming, LTE opens up for two typical roaming scenarios – both having their pros and cons.

Traditional roaming using “home routing” of all data traffic to HPLMN. From a network perspective, this method is very inefficient, but it provides great control when it comes to tariffs and enables services an ability to trigger other applications.

Local brake-out in VPLMN. With the local break-out method it is possible to provide efficient network utilisation by routing the data in a more optimal manner. However, in order to maintain the control from the HPLMN a number of bilateral agreements and interfaces must be established. As an example, it would enable a VoLTE call to be controlled by the IMS system in the HPLMN and at the same time route the actual voice communication with local break-out in the VPLMN.

Jonas Petersson, Senior Technology Advisor LTE & IMS at Polystar, commented on the LTE trends and challenges at the LTE World Summit (video). 

If you would like to learn how your company can benefit from a fast and efficient LTE network monitoring deployment, please contact us at marketing@polystar.com