The idea of a busy office having rows of permanently occupied desks, a buzz of conversation and ringing desk phones has gone the way of, well, the typewriter.

Hybrid and remote working, the preferred mode of work for about 6 in 10 employees around the world at present, has forced organizations to rethink their physical workspaces and how their employees communicate and collaborate.

So, while they reduce and redesign their office space to save on rent while creating well-planned meeting spaces – now a major reason for office attendance on certain days – they are also investing in digital collaboration tools like Microsoft Teams.

Using these tools, employees can easily communicate via webchat or video call and share documents and other information in real time – so efficiently that the need for a traditional landline disappears. Full calling functionality can be activated within Teams itself, for example, allowing employees to receive or make calls outside the organization.

More mobile devices in the workplace

But hybrid work has also increased employees’ use of mobile devices in their jobs. While platforms like Teams are great at helping them communicate, the majority still prefer making business calls natively on their mobile phones.

By late 2020, as the world was still adapting to a mostly hybrid work environment, a Metrigy global study found that almost 70% of organizations had adopted mobile unified communications clients but less than 6% were using them for calling. This is not ideal when organizations want their employees’ phone calls to be secure and compliant.

Fast forward to now, and mobile phones are prevalent in the workforce. According to Tango Networks’ Tango Survey Report issued in October 2023, 77.5% of front-line workers are using mobile phones to carry out their work duties. Also, 56% are using their personal mobile phones, which shows support for the idea of bring-your-own device (BYOD) policies without the hassle of carrying multiple devices.

This is where eSIM solutions have emerged, to address the rising use of personal devices and bridge the gap between mobile calling and compliant Teams calling while supporting organizations’ sustainability goals.

Making work calls on the go

Deskbound employees can easily be trained to make calls via the Teams desktop client, for instance. But what about employees working mostly in the field, such as sales representatives or delivery drivers? They’re used to making phone calls on the go but are likely to find navigating to the keypad dialler in the Microsoft Teams app less convenient than using their phone’s native calling functionality.

Working with Tango Networks, a technology provider in the Microsoft ecosystem, we have created an innovative mobile gateway called NTT Extend that connects to Teams to provide access from a public switched telephone network (PSTN) carrier.

On an employee’s phone, this is implemented through an eSIM that enables the phone to receive and make Teams calls via its native calling interface, just like regular mobile calls. The number used is an “office number” – like the traditional landline number that would ring on a desk phone.

To activate the service, the employee scans a QR code that takes them to a corporate web page from where the eSIM installation will start. Then, they make calls from their mobile device as they usually would. There’s no need for training on Teams – in fact, they don’t even need to know that Teams is providing the functionality in the background.

So, even when the organization does not provide phones or employees prefer to use their own devices, they can still connect to Teams and handle work calls on their own phones.

They still have a business phone number and, because they are now connected to Teams, their availability status – busy on a call, in a meeting or offline, for example – is displayed in Teams for the benefit of their colleagues.

Configuration, cost and compliance benefits

For the IT team, configuration is simple. They can set policies in Teams for office and field workers, like determining which groups are allowed to make international calls.

The eSIM number is no more expensive than a landline because it relies on the same NTT DATA calling plans used with Microsoft Operator Connect. Also, the organization is not purchasing mobile equipment (phones or devices), which means lower costs and less time and effort spent on procurement.

While platforms like Teams are great at helping employees communicate, the majority still prefer making business calls natively on their mobile phones

Speaking of procurement, the hassle of selecting multiple mobile carriers to service global locations is removed: this solution can be sourced from NTT DATA as a single provider. Organizations can also combine this eSIM service and NTT DATA’s fixed telephony service for Teams that leverages Microsoft Operator Connect – all in a single contract. By doing so, they get the benefit of a holistic view of their corporate telephony spending (fixed and mobile users) on one invoice.

When it comes to compliance and security, NTT DATA’s Compliance Recording for Teams can take care of call recording for industries such as financial services, where this is a requirement. There are fewer privacy concerns, too, because the eSIM does not store data – making this solution a relatively secure way of supporting a bring-your-own-device policy.

Overwhelmingly, organizations are recognizing the value of eSIMs compared with fixed telephony, with 99% of respondents in the Tango Networks report saying they will consider eSIM products to replace desk and Internet Protocol (IP) phones.

A huge boost for sustainability

According to Deloitte Global, a new smartphone generates an average of 85kg in carbon-dioxide or equivalent emissions in its first year of use – with nearly all of these emissions emanating from the manufacturing process, including the extraction of raw materials and shipping – and another 8kg from usage during its working life.

Issuing eSIMs to employees eliminates the need for corporate phones. This means there are fewer devices and less packaging in circulation, as well as less ewaste to process.

In terms of energy use, employees with both business and personal phones are likely to keep both devices charged daily – which means they use twice the amount of electricity needed to charge a single phone. With the eSIM option, just one device is plugged in, which means less of a drain on power.

There is also no eSIM production process involving plastic, like for a traditional SIM card, and because this ecosystem is entirely digital, there is little or no actual paperwork.

So, NTT Extend is a natural fit as organizations embrace hybrid and remote working and look to enable employees to do their jobs anywhere, anytime – all while pursuing sustainability goals in support of a better world.


NTT Extend for Microsoft Teams is now available. Contact us to see how NTT Extend can benefit your organization.