Cloud Telephony with Microsoft Teams - FGH’s Success Story

Cloud telephony on Teams is a Microsoft technology that makes it possible to replace the old conventional PBX system.

For decades, companies relied on PBX (Private Branch Exchange) systems as the backbone of their communications. These systems managed internal and external calls from physical servers installed on company premises. They worked. But they came at a cost: expensive hardware, constant maintenance, limited flexibility for remote work, and virtually no integration with other digital tools.

Organizations needed to communicate from any device, in any location, without depending on a physical telephone line. Microsoft Teams Phone System addressed that challenge by delivering the same PBX capabilities, but without complex equipment and without the costs associated with physical maintenance.

One of its many benefits is that users can keep using their extension regardless of where they are physically located. It offers centralized management and can coexist with conventional telephony systems.

Calls between users within the organization are managed internally by the phone system and never pass through the Public Switched Telephone Network (PSTN). This also applies to calls between users located in different geographic regions, eliminating long-distance costs for those internal calls.

What once required a rack of servers, contracts with multiple carriers, and dedicated technical staff can now be managed from a web console integrated into the same environment where teams meet, chat, and collaborate.

FGH’s Communication Model

FGH S.A. is a company with more than 100 years of history in San Rafael, Mendoza, Argentina. It offers a team of professionals dedicated to every aspect of construction. How Do You Evolve from a Traditional Phone System to a Data-Driven Communication Model?

FGH’s transformation, like that of many other organizations where we are implementing cloud telephony, provides a clear example of how data management and control, team connectivity, and workflow integration improve planning and execution, creating processes that are more accessible, efficient, and measurable.

At FGH, the company was able to maintain telephone communication during the pandemic, even while employees were working from home. In addition, the organization achieved significant cost savings, since it no longer needed maintenance services or the purchase of additional devices for its legacy PBX or IP central system.

By deciding to migrate to Microsoft Teams Phone, FGH moved from a hardware-centered model to one focused on people and productivity.

“It helped us tremendously, especially in communication. Being able to see suppliers face-to-face — people we had been speaking with for years — and having the ability to share information instantly, even from a mobile phone, has been very valuable.” Liliana, Manager at FGH

With Teams Phone, FGH consolidated all of its communications — calls, meetings, messaging, and collaboration — into a single platform. Internal calls between users no longer traveled through the PSTN, eliminating long-distance charges between locations. Administration shifted to the Teams Admin Center, providing complete visibility into numbers, users, and system performance.

How Do You Evolve from a Traditional Phone System to a Data Communication Model?

The transition from a traditional PBX to cloud telephony does not happen overnight, but the process is well defined. There are three technical concepts worth understanding before starting the migration.

What Is Microsoft Teams Phone System?

Microsoft Teams Phone System is Microsoft’s technology that enables call control and PBX capabilities from the cloud, directly integrated into Microsoft Teams. It allows users to make, receive, and transfer calls, manage voicemail, call queues, auto attendants, and real-time transcription, all from the same environment where teams work every day. Unlike a physical PBX, it does not require on-premises hardware. Updates are applied automatically, and scaling is straightforward:

• Add users
• Enable new locations
• Onboard remote employees

All of this can be done from the administration portal in minutes.

What Options Are Available to Connect to the Public Telephone Network (PSTN)?

For Microsoft Teams users to make calls to external numbers outside the organization, Teams Phone must be connected to the PSTN. There are two main options:

Microsoft Calling Plans

Microsoft directly provides the phone numbers and calling minutes. This is the simplest option, with no need for additional carrier contracts. It is available in selected markets.

Direct Routing

Direct Routing allows Teams Phone to connect to the organization’s telephony provider through a Session Border Controller (SBC). This option offers greater flexibility in provider selection, access to more competitive rates, and coverage in markets where Microsoft Calling Plans are not available. It is the preferred choice for organizations that already have active carrier contracts or operate across multiple countries.

There is also an intermediate model called Operator Connect. In this model, the telephony provider — certified by Microsoft — manages the connection directly within the Teams Admin Center, without the need to configure an SBC.

What Are the Concrete Steps for Migration?

Migrating from a traditional PBX typically includes:

• Assessment of the current infrastructure: inventory of existing PBX systems, active numbers, contracted carriers, and calling usage patterns by location.
• Definition of the PSTN connection model: based on geographic coverage, existing contracts, and environmental complexity, the organization selects between Calling Plans, Direct Routing, or Operator Connect.
• Configuration of the Microsoft Teams Phone environment: enabling Phone System within the Microsoft 365 tenant, configuring auto attendants, call queues, and routing policies.
• Number porting: existing phone numbers are transferred to Microsoft Teams, preserving the organization’s phone identity without disruption for customers or suppliers.
• Pilot with a small user group: before large-scale migration, performance is validated with a specific group, friction points are identified, and configuration is adjusted.
• Phased rollout and adoption: migrating in phases reduces operational risk and allows users to adopt the new platform with active support.
• Monitoring and optimization: once deployment is complete, the Teams Admin Center provides real-time call quality metrics, per-user usage, and service alerts.

Every organization has a different infrastructure, carriers with contracts under different terms, and users with varying levels of technological adoption. The experience of the partner supporting the migration determines whether the transition becomes a high-impact project or a source of operational friction.

From Technology to Real Adoption

ROI comes when users adopt the platform and integrate it into the way they work. That means training, guidance during the first days of use, and clear metrics to measure impact.

In its independent voice services benchmark (September 2022), GigaOM awarded Microsoft Teams Phone the highest scores in uptime and service quality among all providers evaluated. But those numbers only become real when implementation is executed correctly and teams understand how to take full advantage of the available features.

Moving from a traditional PBX to a cloud telephony model is not simply a matter of switching tools. It is about transforming the way an organization communicates, with data, control, and flexibility that analog systems were never able to provide.

Frequently Asked Questions About Cloud Telephony with Microsoft Teams

Can Microsoft Teams Phone fully replace a traditional PBX?

Yes. Microsoft Teams Phone System offers all the functionality of a traditional PBX (including auto attendants, call queues, voicemail, call transfers, and music on hold) while extending those capabilities with cloud-native features such as real-time transcription, intelligent routing, and integration with the Microsoft 365 ecosystem. The migration eliminates dependence on physical hardware and consolidates management into a single administrative console.

What happens to existing phone numbers during migration?

Existing numbers are ported to Microsoft Teams through a number porting process. This ensures that the organization keeps its phone numbers without disruption for internal users, customers, or suppliers. The process requires coordination with the current carrier and may take several business days depending on volume and geographic coverage. What is the difference between Calling Plans and Direct Routing? Calling Plans is the option in which Microsoft acts directly as the carrier, providing both phone numbers and calling minutes. Direct Routing, by contrast, allows Teams to connect with the organization’s telephony provider through a Session Border Controller (SBC). Direct Routing is more flexible, covers a wider range of markets, and often offers more competitive pricing, but it requires more technical configuration. The right choice depends on geographic coverage, current contracts, and the complexity of the environment. How long does a migration from PBX to Microsoft Teams Phone take? The timeline varies depending on the size of the organization, the number of locations, the volume of numbers to be ported, and the complexity of the current infrastructure. A pilot with a small group can be completed in just a few weeks. A full rollout for mid-sized and large organizations typically takes between two and four months, including planning, configuration, number porting, and adoption phases.

Is it safe to migrate critical communication systems to the cloud?

Yes, as long as the migration is carried out with proper planning and with a partner that has proven experience in critical environments, such as Possumus. Microsoft Teams Phone runs on Microsoft Azure infrastructure, which meets international security certifications and high availability standards. A phased migration strategy — starting with a pilot and scaling progressively — minimizes operational risk and ensures service continuity throughout the transition.

What devices are compatible with Microsoft Teams Phone? Teams Phone is compatible with more than 150 Microsoft-certified devices, including IP phones, headsets, speakerphones, and video conferencing displays from different manufacturers. Users can also make and receive calls from their computer, tablet, or mobile phone, using a single business phone number regardless of device or location.

About Possumus

We are a company focused on creating value, helping organizations achieve digital transformation through strategy, knowledge, and innovation. Our processes are accredited under the ISO 9001:2015 quality certification for software development. www.possumus.tech