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GCC High for MS Teams | Government | C3 Integrated Solutions

Enabling GCC High with Voice and Audio Conferencing via Microsoft Teams Direct Routing

Empowering Organizations with a Teams Voice Solution


C3 Integrated Solutions and CallTower: Delivering Voice Solutions for GCC High

C3 Integrated Solutions is a full-service IT provider specialising in securing the Defense Industrial Base through cloud-based solutions and industry-leading partnerships. As a provider of Microsoft Government Cloud solutions, including Microsoft 365 GCCGCC High, and Azure Government, C3 helps clients achieve CMMC and NIST 800-171 compliance through tailored managed services, security, and Microsoft 365 integration.


The Challenge

Microsoft GCC High is designed to meet the unique security and compliance needs of the Defense Industrial Base, including:

  • Residency in Azure Government.
  • Full U.S. data sovereignty.
  • Limited third-party integration.

GCC High meets the rigorous standards of:

  • NIST 800-171.
  • DFARS 252.204-7012.
  • International Traffic in Arms Regulations (ITAR).
  • Cybersecurity Maturity Model Certification (CMMC).

As one of fewer than ten authorised sellers of Microsoft 365 GCC High for organisations with under 500 users, C3 Integrated Solutions is uniquely positioned to deliver tailored GCC High solutions. However, a critical gap existed: Microsoft does not offer voice services for GCC High.

With the rise of remote work during the global pandemic, more companies demanded collaborative voice and audio-conferencing options within GCC High. To address this gap, C3 sought a partner capable of delivering Microsoft Teams voice and telephony solutions built specifically for the GCC High environment.


The Solution

After exploring options, C3 partnered with CallTower, a long-standing Microsoft Gold Partner with extensive experience hosting Microsoft voice solutions. Together, they developed a solution to meet the complex requirements of voice-enabled Microsoft 365 GCC High.

CallTower’s Microsoft Teams Solution

  • Direct Teams Routing: A PSTN solution that replicates a PBX model to support voice services for GCC High.
  • Seamless Integration: Enabled dial-in conferencing and PSTN calling through Microsoft Teams, just like the commercial version of Microsoft 365.

What They Said

“One of the biggest challenges for our clients in GCC High was the lack of voice services. This slowed adoption and added complexity to the transition. When we considered how to fill this gap, we knew the solution would be complex. CallTower had the skill and expertise to help us do just that.”
– C3 Integrated Solutions

“CallTower’s voice-enabled O365 GCC High solution fills a void in the government contractor vertical that is currently supported with a lot of limitations. We’re proud that CallTower’s technology and experts deliver such an effective and secure solution to this government sector.”
– CallTower


The Results

The partnership between C3 Integrated Solutions and CallTower has delivered significant benefits for GCC High clients:

1. Voice-Enabled GCC High

  • Clients can now facilitate dial-in conferencing and PSTN calling through Microsoft Teams, just as they would in the commercial version of Microsoft 365.

2. Accelerated Adoption

  • The solution accelerates the adoption of Microsoft Teams within GCC High organisations and encourages migration to Microsoft 365 GCC High.

3. Enhanced Collaboration

  • Government contractors operating in security-sensitive environments can now connect and collaborate more effectively.

Why Choose C3 and CallTower?

If your organisation requires a secure GCC High environment or is already operating within GCC High, C3 Integrated Solutions and CallTower can deliver tailored voice and telephony solutions to help your business connect and collaborate seamlessly.


About CallTower

CallTower is your trusted partner for seamless, intelligent communication solutions. We specialise in:

  • Unified Communications as a Service (UCaaS).
  • Contact Center as a Service (CCaaS).
  • Conversational AI (CAI) technologies.
  • End-to-end professional and managed services.

Our innovative and scalable solutions are designed to:

  • Streamline workflows.
  • Optimize IT infrastructure.
  • Empower businesses to connect, collaborate, and grow with ease.

At CallTower, we redefine communication by combining innovation and expertise to drive meaningful connexions and lasting success.

C3
C3

GCC High for MS Teams | Government | C3 Integrated Solutions