T-MOBILE USSUCCESS STORY

FAST & ERROR-FREE REPARENTINGT-Mobile US and Ericsson complete massive migration in record time with 100% success rate

CUSTOMER PROFILEAs America’s Un-carrier, T-Mobile US, Inc. (NASDAQ: TMUS) is redefining the way consumers and businesses buy wireless services through leading product and service innovation. The Company’s advanced nationwide 4G LTE network delivers outstanding wireless experiences to approximately 63 million customers who are unwilling to compromise on quality and value. Based in Bellevue, Washington, T-Mobile US provides services through its subsidiaries and operates its flagship brands, T-Mobile and MetroPCS.

For more information, please visit http://www.t-mobile.com.

In 2015 T-Mobile US wanted to modernize its GSM Radio Access Network (RAN) by reparenting 2G base stations from legacy Base Station Controllers (BSCs) to new Evo BSCs. The project needed to be performed fast and error free. Ericsson provided

a new reparenting solution for massive migration which enabled greater efficiency and flexibility of this network and satisfied the customer’s needs. It resulted in simpler network management, smaller carbon footprint and reduced power consumption.

The challengesT-Mobile US requested accurate, error free reparenting of base stations with minimum interruption of customer traffic. An additional request to Ericsson was to provide efficient volume reparenting execution. As an ideal goal, T-Mobile US requested safely reparenting the entire set of Legacy BSC sites onto one or more Target Evo BSCs within a given single T-Mobile US maintenance window (one night’s work). This request was particularly challenging as Ericsson has a lot of experience

in reparenting, but not in such a large scope concentrated in one single maintenance window while keeping the costs within reasonable boundaries.

The taskThe project was to reparent 77 old BSCs that contained around 7000 mobile base stations. The base stations had to be reparented “like-as-like,” meaning all base stations should contain the same configuration in terms of transmission, site hardware configuration and radio parameter configuration with no radio retuning. The Transceiver Group numbers, Digital Paths and Location Area Code of each site were changed to avoid collisions on the new BSCs. In one single maintenance window, the following types of reparenting were supported: multiple source BSCs to one

MOVING THE BOUNDARIES

The rehomes were flawlessly executed thanks to our strong partnership with Ericsson.” Salim KouidriSenior Director of Engineering & Operations, T-Mobile US

destination BSC, one source BSC to multiple destination BSCs as well as multiple source to multiple destination BSCs. Reparenting of multiple source and destination BSCs on different Operation Support Systems was also supported. The scope included reparenting of base stations, moving 2G-3G and 2G-4G relations and updating the MSC (Mobile Switching Centre). Reparenting was performed for each base station. Fallback was supported, but it was not needed.

Reparenting was done in the T-Mobile US Northeast and Southeast Regions: New England, New Jersey, Philadelphia and Washington, D.C.

The teamFor the T-Mobile US reparenting project, Ericsson involved four different teams located in four different countries, all coordinated through the local Ericsson USA team.

The resultInitially, reparenting was planned to be performed during a 10-month period with 42 working weeks. Each week 200 base stations were planned to be reparented or 40 sites per night.

The reparenting was immensely successful and performed in a 3.5 month time frame with only 12 working weeks. An average rate of 100 base stations reparented per each night was achieved. The total number of sites per night was 3 times more than in the previous process. Reparenting was performed each consecutive night, 5 nights per week without problems. Every day new preparation was performed for a new night reparenting activity. Therefore execution of the project provided much more than planned at the beginning of the whole project.

Roberto Bulleri, Program Manager for T-Mobile US

Reparenting was highly satisfied with this achievement: “This project is very special as we have reinvented reparenting, at times performing more than 200 sites per night. Epic. We had to learn along the way; we are not perfect, but we owned up to our mistakes and we told the customer what was happening in their network before they knew it. The customer has thanked me for that. That is accountability in its purest form. Every person and engineer in this project worked tirelessly for countless hours. Every challenge was turned into an opportunity, every opportunity into a solution. I am proud of what we have achieved together. This project opens new doors for Ericsson in T-Mobile US.”

Reparenting time was reduced three fold Weekly number of reparented base stations increased 3X

Old process Old processNew Ericsson process New Ericsson process

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We have reinvented reparenting, at times performing more than 200 sites per night… I am proud of what we have achieved together.” Roberto BulleriProgram Manager for T-Mobile US reparenting

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Ericsson AB

SE-126 25 Stockholm, Sweden

Telephone +46 10 719 0000

www.ericsson.com

Draft – Not for distribution

© Ericsson AB 2015

CUSTOMER

T-Mobile US

CHALLENGE

In 2015 T-Mobile US wanted to

modernize its GSM Radio Access

Network (RAN) by reparenting 2G

base stations from legacy Base

Station Controller (BSC) to new

Evo BSC. The project needed to be

performed fast and error free, with

minimum interruptions of customer

traffic.

SOLUTION

> Automated reparenting process

implemented

> Ericsson performed all

reparenting services

RESULTS

> All 77 legacy BSCs that contained

around 7000 mobile base stations

reparented “like-as-like” to 17

new Evo BSCs in just 3.5 months,

3 times faster than planned

> Average rate of 100 base station

reparented per each night was

achieved

> The Transceiver Group numbers,

Digital Paths and Location Area

Code of each site were changed

to avoid collisions on the new

BSCs

> Reparenting of multiple source

and destination BSCs on different

Operation Support Systems was

also supported. The scope also

included moving 2G-3G and

2G-4G relations and updating the

MSC.

overview

Extra valueIn addition to the successful project that moved the boundaries of possible reparenting speed and performance, Ericsson provided additional benefits for T-Mobile US:

> Cut time-to-market by 70%

> Reduced overall power consumption faster

> Eliminated costs on Legacy BSCs sooner

> Freed T-Mobile US resources to focus on other activities

Successful reparenting opened new opportunities for reparenting in T-Mobile US. This project was an excellent demonstration of Ericsson’s mission to lead transformation through mobility. In this role Ericsson is the driving force behind the Networked Society.

Our leadership in communications technology and services, coupled with unrivalled global reach and footprint, is the means by which we are building the fabric of the Networked Society, transforming networks to meet future user needs.