Choosing the Right Cloud Model for Enterprise Communications

Cloud communications is no longer a simple choice between keeping technology on-site or moving everything into a public cloud platform.

Enterprise environments are more complicated than that.

An organisation may want Microsoft Teams for collaboration, retain Mitel for critical enterprise voice, use a cloud contact centre for customer service, route calls through a separate SIP platform and keep particularly sensitive communications within UK-controlled infrastructure.

None of those decisions is inherently right or wrong.

The important question is which deployment model provides the right level of flexibility, control, resilience and security for each workload.

Current UK data reflects this mixed environment. The UK Business Data Survey 2026, published by the Department for Science, Innovation and Technology on 18 June 2026, found that among businesses handling digitised data, 31% used a public cloud provider, 27% used servers on business premises and 19% used a private cloud provider.

Mitel similarly reports that Techaisle research found 92% of organisations modernising communications are choosing hybrid approaches, reflecting requirements around efficiency, control, compliance and AI readiness.

The enterprise communications debate has therefore moved beyond cloud or no cloud.

It is about where each service should run and who should control it.

What Are The Main Cloud Models For Enterprise Communications?

Enterprise communications can be delivered through several different architectures.

The terminology matters because two solutions described as "cloud communications" can provide very different levels of control, tenancy, data location and operational responsibility.

Model	What It Means	Where It Can Fit
Public cloud	Services delivered through shared cloud infrastructure	Standardised UCaaS, collaboration and applications where scalability and rapid deployment are priorities
Private cloud	Dedicated infrastructure or instances designed for one organisation	Organisations requiring greater control, customisation, security or protection of existing investments
Hybrid	A combination of cloud and on-premises or different cloud environments	Enterprises with mixed workloads, legacy investments, regulatory requirements or phased transformation
Sovereign communications	Communications designed around defined jurisdiction, operational control, data residency and management requirements	Government, healthcare, finance and other organisations with stronger sovereignty or regulatory requirements
On-premises	Communications infrastructure retained within the organisation's own environment	Workloads requiring direct infrastructure control or where migration does not yet provide sufficient business value

There is no requirement for every workload to use the same model.

The stronger strategy is to understand the characteristics of each communications service and place it where it performs best.

Why Is Hybrid Communications Becoming More Important?

Hybrid used to be treated largely as a transitional state between on-premises technology and public cloud.

That assumption is becoming outdated.

For many enterprises, hybrid is now the intended architecture.

A business might use:

• Microsoft Teams for collaboration
• Mitel for enterprise voice
• Five9 or 8x8 for contact centre
• NetX for SIP routing and number control
• Private cloud for sensitive infrastructure
• Public cloud applications for selected workloads
• UK sovereign communications for services requiring greater jurisdictional control

The advantage is choice.

Organisations do not have to replace systems that continue to provide value simply because another workload is moving to the cloud.

Mitel's 2026 communications strategy explicitly supports dedicated instance, private cloud, public cloud and on-premises environments rather than assuming a single deployment model.

For enterprise communications, this can provide a more practical route to modernisation because technology can change at different speeds.

When Does Public Cloud Make Sense?

Public cloud communications can be highly effective where organisations prioritise:

• Rapid deployment
• Subscription-based consumption
• Scalability
• Distributed users
• Standardised functionality
• Regular platform updates
• Reduced infrastructure management

Platforms such as Microsoft Teams, Zoom, 8x8 and Five9 demonstrate how communications and customer experience capabilities can be delivered as cloud services.

For many workloads, that model works extremely well.

The mistake is assuming the benefits make public cloud automatically suitable for every communications requirement.

Enterprises should still consider:

• Data location
• Regulatory requirements
• Service dependencies
• Resilience
• Integration
• Customisation
• Exit strategy
• Connectivity
• Supplier concentration
• Operational control

A public cloud platform can remove responsibility for running infrastructure without removing the organisation's responsibility for understanding how the service supports its business.

When Does Private Cloud Make More Sense?

Private cloud can be appropriate where an organisation wants cloud-style management and resilience while retaining more control over the environment.

This can be particularly relevant where businesses have already invested heavily in enterprise communications technology.

Britannic's Private Cloud for Mitel, for example, allows organisations to retain supported Mitel technology and licences while moving the underlying infrastructure into Britannic's UK private cloud.

The platform uses dual UK data centres and is backed by a 99.999% uptime SLA.

This can provide a different migration path from replacing the entire communications estate with a new UCaaS platform.

Private cloud can therefore be valuable where the objective is to:

• Protect existing investment
• Remove on-site infrastructure
• Improve resilience
• Retain greater environmental control
• Maintain specialist integrations
• Modernise progressively
• Meet specific security or data requirements

The decision should still start with the workload and business requirement rather than the deployment label.

What Is Sovereign Communications?

Cloud location and digital sovereignty are related, but they are not identical.

A service can be hosted in the UK without every operational, routing or management component necessarily being under UK control.

Sovereign communications considers a broader set of questions, including:

• Where is the infrastructure?
• Where does communications data reside?
• Where is voice traffic routed?
• Who manages the service?
• Which jurisdiction applies?
• Who can access metadata?
• Where are support and operational teams located?
• How much infrastructure is shared with other organisations?

Britannic's Sovaris proposition was launched with Mitel in June 2026 to address this requirement.

Sovaris combines private-instance Mitel communications with Britannic-owned UK infrastructure, NetX SIP and routing, managed connectivity, network security and UK-based management and support. Britannic states that the platform keeps communications data and voice traffic within the UK and is backed by a 99.999% availability SLA across SIP and telephony services.

This provides another communications model for organisations where public-cloud convenience needs to be balanced against sovereignty, jurisdiction and operational control.

Why Does Data Location Matter?

Data residency is increasingly part of cloud architecture discussions, particularly for organisations operating in regulated or sensitive sectors.

However, asking "Where is the data hosted?" is only the beginning.

Organisations should also understand:

• Where backups reside
• Where call recordings are stored
• How metadata is handled
• Where voice signalling is processed
• Who administers the environment
• Whether overseas teams can access the platform
• Which subcontractors are involved
• Which jurisdiction governs the provider
• How encryption keys are controlled

These questions can have very different answers even when two services are both described as UK hosted.

For highly regulated organisations, cloud architecture is therefore becoming as much a governance decision as a technology decision.

How Important Is Security When Choosing A Cloud Model?

Security should be assessed across every deployment model.

Public cloud is not automatically insecure. Private cloud is not automatically secure. Keeping systems on premises does not remove cyber risk.

The security outcome depends on the architecture, controls, configuration, monitoring and governance surrounding the service.

The Government's Cyber Security Breaches Survey 2025 to 2026, published on 30 April 2026, found that 43% of UK businesses identified a cyber security breach or attack in the previous 12 months. This increased to 65% of medium businesses and 69% of large businesses.

Cloud communications assessments should therefore consider:

• Encryption
• Identity and access
• Multi-Factor Authentication
• Role-based access
• Network security
• Vulnerability management
• Fraud controls
• Monitoring
• Incident response
• Backup and recovery
• Supplier security
• Configuration management

Britannic combines cloud and communications services with security capabilities and holds certifications including ISO 27001 and Cyber Essentials Plus.

Security needs to follow the communications workload regardless of where that workload resides.

Why Is Connectivity Part Of The Cloud Decision?

A cloud platform is only useful while users can reach it.

Moving communications into cloud services increases dependence on network connectivity.

Organisations should therefore consider:

• Primary connectivity
• Diverse network routes
• Internet resilience
• Mobile backup
• SIP resilience
• Local power
• Business continuity
• Failover
• Network performance
• Quality of Service

Britannic's Unlimited Cellular Backup, for example, provides an independent mobile path that can maintain connectivity for internet, communications, payment terminals and other critical services during a primary network outage.

Cloud strategy should therefore assess the service and the route to the service.

This is particularly important for enterprise voice and contact centres, where even a short loss of connectivity can immediately affect employees and customers.

How Does NetX Fit Into A Hybrid Cloud Strategy?

Enterprise communications can become difficult to manage when organisations use several platforms at once.

Britannic's NetX platform provides a communications and SIP layer capable of connecting platforms including Microsoft Teams, Zoom and Mitel while providing routing, number management, resilience, analytics and failover.

NetX is built around a carrier-grade architecture and backed by a 99.999% SLA.

This allows organisations to separate the communications network layer from the individual application.

For example, a business could migrate one department to Microsoft Teams while retaining another communications environment and continue managing voice routing through NetX.

This can make phased migration considerably more practical.

Rather than:

Old Platform → Complete Replacement → New Platform

the architecture can become:

Existing Platforms + New Platforms → Common Communications Layer

That reduces the pressure for every technology decision to happen at the same time.

What Does The PSTN Switch-Off Mean For Cloud Communications?

The UK's retirement of the Public Switched Telephone Network provides another reason organisations need to review communications architecture.

Openreach confirmed on 31 July 2026 that the PSTN will be retired on 31 January 2027, with around 350,000 business premises still using the legacy network at that point.

The issue goes beyond conventional telephone lines.

Organisations also need to identify services such as:

• Lift emergency lines
• Alarm systems
• Payment terminals
• Fax
• Door entry
• Monitoring devices
• Building systems
• Other analogue equipment

Moving enterprise voice into the cloud does not automatically solve those dependencies.

Britannic can support digital voice migration through NetX, while PSTN Assure provides managed continuity for supported PSTN-dependent services using Metallic Path Facility where immediate migration is not yet practical.

This reinforces a broader principle.

Cloud transformation needs to examine the complete communications environment, not simply user telephony.

Why Does Integration Matter More Than Being 'Cloud Native'?

The original version of this article placed significant emphasis on whether technology was API-centric.

Integration remains important, but the more useful question in 2026 is:

Can the communications environment exchange the information required to support the business process?

That may involve:

• APIs
• SIP
• Webhooks
• CRM integrations
• Workflow platforms
• Microsoft Teams
• Contact centres
• AI
• Reporting
• Authentication platforms

A cloud application that cannot exchange the information an organisation needs can still create a silo.

An existing platform with strong integration may deliver considerably more value.

This is why Britannic positions itself as a systems integrator rather than simply a cloud reseller. The objective is to connect communications, networks, data and applications into an operating environment aligned to the business outcome.

The Britannic Cloud Fit Test

Before deciding where a communications workload should run, Britannic recommends assessing five areas.

Control

How much control does the organisation require over infrastructure, configuration, routing and administration?

Compliance

What requirements apply to data, recording, communications, jurisdiction and regulatory oversight?

Continuity

What happens if the platform, data centre, carrier or internet connection becomes unavailable?

Connectivity

What networks, SIP services, applications and business systems need to connect with the workload?

Change

How easily can the environment scale, integrate, migrate or adopt new capabilities over time?

Control → Compliance → Continuity → Connectivity → Change

No deployment model will produce the same answer for every workload.

That is the point.

The architecture should follow the organisation's requirements rather than forcing those requirements to fit the cloud model.

What Should Businesses Review Before Moving Communications To The Cloud?

Organisations should ask:

• What business problem is the migration intended to solve?
• Which communications workloads are being reviewed?
• Does everything genuinely need to move?
• Which existing investments still provide value?
• What level of infrastructure control is required?
• Where will data be stored?
• Where will voice traffic and signalling be processed?
• Who can access or administer the service?
• Which jurisdictions apply?
• Are there regulatory or sovereignty requirements?
• What is the platform's resilience architecture?
• What SLA applies?
• What happens if primary connectivity fails?
• Are diverse network routes available?
• How are calls protected against fraud?
• Can the platform integrate with existing systems?
• Can migrations happen in stages?
• Are there legacy PSTN dependencies?
• What is the exit or migration strategy?
• Who is responsible for ongoing optimisation?

If those questions are answered only after a platform has been selected, the cloud decision is happening in the wrong order.

The Best Cloud Strategy May Use More Than One Cloud

Enterprise communications has moved beyond the assumption that everything eventually belongs in the same public cloud.

Different workloads carry different requirements.

Collaboration may benefit from public cloud. Established enterprise voice may be retained and hosted privately. Sensitive communications may require sovereign controls. Contact centres may use another cloud platform entirely. NetX can provide a common communications layer across them.

The objective is not to become more cloud.

It is to create a communications environment that provides the appropriate balance of control, resilience, integration, security and flexibility.

Britannic designs and integrates public, private, hybrid and sovereign communications environments, combining global platforms with its own NetX technology, UK infrastructure and managed services.

Organisations reviewing their communications architecture can book a complimentary meeting with Britannic to assess which workloads should be retained, integrated, migrated or moved into public, private, hybrid or sovereign environments.