DaaS Deployment Models Compared: Public, Private, and Hybrid Cloud Desktops

Your IT budget approval just came through. You're finally replacing those aging desktop PCs and moving to virtual desktops. But now comes the harder question: public cloud, private cloud, or hybrid?

This is a framework choice that will dictate your infrastructure costs, compliance posture, and operational flexibility for the next three to five years. Choose wrong, and you'll either overspend by 40% on unused capacity or scramble to meet unexpected compliance audits.

Choose right, and you'll have infrastructure that scales with your business whilst keeping finance happy.

Public cloud desktops, private cloud VDI, and hybrid approaches each handle infrastructure differently. The deployment model you select determines who manages your infrastructure, where your data lives, and whether your costs stay predictable or fluctuate with usage. The old binary choice between "on-premises or cloud" has evolved into something more nuanced.

This guide breaks down the three deployment models for virtual desktop infrastructure, showing you exactly when each one makes sense for your organisation.

The Three Deployment Models Explained

Desktop virtualisation comes in three distinct deployment models, each representing a fundamentally different approach to where your infrastructure lives and who controls it.

Public cloud desktops run on shared infrastructure managed by providers like Azure, AWS, or Google Cloud. You're renting desktop capacity from massive data centres, paying only for what you use.

The provider handles hardware maintenance, capacity planning, and infrastructure security. Your IT team focuses on desktop configuration and user management.

Private cloud VDI means dedicated infrastructure that only your organisation uses. This could be physical servers in your data centre or dedicated capacity within a provider's facility.

Either way, you get complete control over hardware specifications, security configurations, and data location. You also shoulder more responsibility for capacity planning and infrastructure management.

Hybrid desktop infrastructure combines both approaches. You might run sensitive workloads on private infrastructure whilst using public cloud for seasonal workers or development environments. The split gives you control where you need it and flexibility everywhere else.

Each model trades off between three variables: control, cost structure, and deployment speed. Public cloud maximises speed and flexibility. Private cloud maximises control and predictability.

Hybrid attempts to capture advantages from both-but adds complexity in return.

The right choice depends less on technology preferences and more on your specific constraints around data sensitivity, budget structure, and workload patterns.

Public Cloud Desktops: Fast Deployment, Variable Costs

Public cloud desktops get you operational faster than any other model. FlexxDesktop can provision new virtual desktops in minutes, not weeks. Need 50 additional desktops for temporary contractors?

You'll have them running by lunch.

Public cloud converts desktop costs to pure operational expenditure. You pay per user per month, typically £30-60 per user monthly-£35 for standard office workers, £55-60 for power users requiring GPU access or high-performance storage. No capital outlay. No three-year hardware refresh cycles.

Finance loves this because it converts unpredictable CapEx into steady, forecastable OpEx. Your CFO can budget desktop costs as easily as office rent.

But usage-based pricing cuts both ways. If users leave desktops running unnecessarily, costs creep up. Data transfer charges can surprise you-one organisation saw bills jump 30% when they didn't account for 4K video editing workflows.

You also sacrifice some control over data location. Whilst reputable providers let you specify the region (UK South, EU West), you're sharing physical infrastructure with other tenants. For most workloads this doesn't matter.

But if you're handling highly sensitive data or operating under strict compliance regimes, that shared tenancy model might conflict with your risk framework.

Public cloud shines for organisations with variable user counts-seasonal businesses, project-based work, or rapid growth scenarios. A recruitment agency scaling from 40 to 120 staff over six months will find public cloud far more economical than buying infrastructure for peak capacity.

Similarly, if your IT team is small and lacks virtualisation specialists, offloading infrastructure management to the provider makes operational sense.

The model struggles when workload is steady and predictable. Running 500 desktops continuously at £45 monthly costs £270,000 annually. Equivalent private infrastructure might cost £180,000 upfront plus £40,000 yearly-breaking even in year two.

Private Cloud VDI: Control and Predictability

Private cloud VDI means you know exactly where every virtual desktop runs and who has physical access to the infrastructure. For regulated industries-financial services, healthcare, government-this certainty is a compliance requirement, not a luxury.

The cost structure inverts completely from public cloud. You're making capital investments in servers, storage, and networking equipment. Budget £150,000-300,000 for infrastructure supporting 200-300 users, depending on performance requirements.

Those are significant upfront numbers, but your per-desktop cost becomes remarkably predictable. Whether users are active 40 hours weekly or 80, your costs stay constant.

Pure private cloud remains the gold standard for organisations that cannot tolerate any ambiguity about data location. When auditors ask "can you guarantee this customer data never left UK soil?" you can answer definitively.

Private infrastructure gives you complete control over security configurations, update schedules, and performance characteristics. Need to enforce disk encryption with specific algorithms? Done.

Want to guarantee minimum IOPS for database workloads? You specify the storage tier. Public cloud offers these options too, but private infrastructure means no compromises with a multi-tenant environment.

The trade-off is deployment time and operational burden. Standing up new private cloud infrastructure takes 8-12 weeks minimum. You need virtualisation specialists on staff or on retainer.

Hardware failures become your problem. Capacity planning becomes critical-underbuild and you're scrambling to add servers when you hit limits; overbuild and you've wasted capital on idle resources.

Private cloud makes sense when workload is stable, compliance requirements are stringent, or you have existing data centre investments to maximise. A financial services firm running 800 desktops for traders and analysts, all requiring sub-10ms latency to trading systems, will find private infrastructure both more economical and more performant than public cloud alternatives.

Hybrid Desktop Infrastructure: Balancing Both Approaches

Hybrid deployment models attempt to capture the best of both worlds: control where you need it, flexibility everywhere else. The architecture typically places sensitive workloads on private infrastructure whilst using public cloud for variable demand.

Consider a professional services firm with 400 permanent staff and 50-150 contractors depending on project load. Core employees work with client confidential data that must stay on private infrastructure for contractual reasons. Contractors need standard desktops without access to sensitive systems.

Running 400 private desktops and 50-150 public cloud desktops optimises both compliance and costs.

Hybrid models also provide resilience. If your primary data centre experiences issues, critical workloads can fail over to public cloud capacity. This disaster recovery capability would require building a second private data centre-a capital investment few organisations can justify.

But hybrid means managing two separate environments. Your IT team needs skills across both platforms. User management becomes more complex-some staff authenticate to private infrastructure, others to public cloud.

Software licensing must account for both deployment models. Desktop images need maintaining in two locations.

The tooling matters enormously here. Unified endpoint management that works across deployment models prevents hybrid complexity from becoming hybrid chaos. Management platforms that support multiple cloud providers through a single console mean your team isn't juggling three different admin interfaces. This multi-cloud flexibility also provides concrete risk mitigation-if your primary cloud provider experiences regional outages, you can shift critical workloads to alternative regions or providers.

Hybrid architectures work best for mid-sized to large organisations (200+ users) with distinct workload categories. If you can cleanly separate "sensitive workloads requiring private infrastructure" from "standard workloads suitable for public cloud," hybrid gives you genuine cost and compliance advantages.

If that boundary is fuzzy or constantly shifting, the management overhead might exceed the benefits.

Which Model Matches Your Budget Structure and Compliance Needs

The right deployment model depends on three primary factors: data sensitivity and compliance obligations, budget structure preferences, and whether your workload demand stays steady or fluctuates.

Data sensitivity and compliance often narrows your options immediately. If you're subject to GDPR with strict data residency requirements, NIS2 critical infrastructure obligations, or DORA financial services regulations, you need clear answers about where data lives.

Public cloud can meet these requirements-but you must verify provider certifications and data centre locations carefully. For organisations where "we're not sure" isn't acceptable, private infrastructure removes ambiguity.

Budget structure shapes deployment feasibility. If your organisation strongly prefers operational expenditure (paying monthly) over capital expenditure (upfront hardware purchases), public cloud aligns naturally with that preference.

Conversely, if you have capital budget available but tight operational budgets, investing in private infrastructure might work better financially.

Consider total cost over three years, not just initial outlay. Public cloud at £45 per user monthly costs £1,620 per user over 36 months. Private infrastructure might cost £800 per user upfront plus £200 annually in operational costs-£1,400 total.

For stable workloads, private infrastructure often wins on pure economics despite higher initial costs.

Workload variability determines which cost model rewards you and which penalises you. If your user count swings by more than 20% throughout the year, public cloud's pay-for-what-you-use model prevents paying for capacity you don't need.

If you run steady user counts year-round, you're paying a premium for flexibility you're not using.

A decision matrix clarifies these scenarios:

• Choose public cloud when you need rapid deployment, have variable user counts, prefer OpEx budgeting, and don't have strict data residency requirements. Example: An architecture firm scaling from 45 to 120 staff over 18 months to fulfil a major contract can add desktop capacity as they hire without overbuilding infrastructure.
• Choose private cloud when you have stringent compliance needs, stable predictable workloads, available capital budget, and internal IT expertise to manage infrastructure. Example: A healthcare provider with 300 clinicians accessing patient records needs guaranteed data residency and consistent sub-20ms application response times.
• Choose hybrid when you have distinct workload types with different security requirements, need disaster recovery flexibility, and have IT resources to manage multiple environments. Example: A legal firm with 200 solicitors handling confidential matters and 80 administrative staff can segregate workloads-private infrastructure for legal work, public cloud for admin functions.

One factor that shouldn't dominate your decision: vendor preference. Unless you have compelling technical reasons to favour a specific cloud provider, prioritising deployment model alignment with your requirements matters more than whether you prefer Azure over AWS.

Before vendor conversations, document three things: your average user count and seasonal variance over 12 months, your specific compliance requirements with regulation names, and whether your finance team has allocated CapEx or OpEx budget for this initiative. These three data points will eliminate 60% of unsuitable options immediately.

Frequently Asked Questions

Can we switch between deployment models after initial setup?

Yes, but the difficulty varies significantly by provider. Moving from public to private cloud (or vice versa) typically requires rebuilding desktop images, reconfiguring network architecture, and migrating user data. With proper planning, expect 4-8 weeks for a controlled migration of 200-300 desktops. The easier path is starting with hybrid architecture, which lets you shift the balance between public and private capacity without wholesale migration. The practical reality: your initial deployment model will likely persist for 2-3 years regardless of theoretical migration capability. Choose carefully rather than assuming you'll switch easily if requirements change.

How does GDPR affect the choice between public and private cloud desktops?

GDPR doesn't explicitly prohibit public cloud desktops. It requires that you know where personal data is processed, ensure adequate security measures, and use processors (cloud providers) with appropriate data protection guarantees. Public cloud can be GDPR-compliant if you select EU data centre regions and verify your provider has Standard Contractual Clauses or adequacy decisions for cross-border data flows. Major providers like Azure and AWS offer GDPR-compliant configurations. Private cloud simplifies compliance evidence-when auditors ask about data location and security controls, you can point to infrastructure you directly control.

What's the typical cost difference between public and private cloud VDI?

For steady-state workloads over three years, private cloud typically costs 15-30% less than equivalent public cloud capacity. A 300-user deployment might total £480,000 in public cloud versus £370,000 in private infrastructure (including hardware, licensing, and operational costs). This arithmetic inverts for variable workloads-if your user count fluctuates by 40% seasonally, public cloud lets you pay only for active users. Hidden costs affect both models: public cloud data egress charges can add 15-20% to baseline costs, whilst private cloud requires 0.1-0.15 FTE per 100 desktops for ongoing management. Request detailed total cost of ownership calculations from providers before committing.

Do we need different technical skills to manage each deployment model?

Yes, though the gap has narrowed. Public cloud emphasises cloud platform expertise (Azure administration, AWS networking, cloud security models) whilst private cloud requires traditional virtualisation skills (VMware, Hyper-V, storage management). Most IT teams can manage public cloud desktops with 2-3 months of training if they have solid general IT fundamentals. The provider handles infrastructure complexity, letting your team focus on user support. Private cloud VDI demands deeper infrastructure knowledge-you need staff who understand capacity planning and storage performance characteristics. Hybrid deployments require both skill sets, or management tools sophisticated enough to abstract away environment differences.