This guide provides a systematic framework for choosing how to deploy AI modelsβvia direct API, enterprise cloud platforms (Azure AI Foundry, AWS Bedrock, Google Vertex AI), or self-hosted infrastructure. The right deployment model profoundly affects cost, control, compliance, and operational responsibility.
Deployment Models Overview
Direct API (SaaS)
What it is: Call the provider’s cloud API directly (e.g., OpenAI API, Claude API, Gemini API).
Key Characteristics:
- Data sent to provider’s infrastructure
- Provider manages everything (updates, scaling, security)
- Pay-per-use pricing
- Fast setup (hours to days)
- Limited control over infrastructure
Typical Cost: Lowest initial; scales linearly with usage
Enterprise Cloud Platforms
What it is: AI models deployed through cloud provider’s managed service (Azure AI Foundry, AWS Bedrock, Google Vertex AI).
Key Characteristics:
- Data processed within your cloud tenancy
- Provider manages model infrastructure
- You control security, networking, IAM integration
- Enterprise SLA and support
- Unified platform for multiple models
Typical Cost: Moderate premium over direct API; enterprise features included
Self-Hosted (On-Premise or Private Cloud)
What it is: Run AI models on your own infrastructure (data center servers or dedicated cloud VMs).
Key Characteristics:
- Complete data control (never leaves your infrastructure)
- You manage everything (deployment, scaling, security, updates)
- Requires technical expertise and ongoing operations
- High fixed costs; low variable costs
Typical Cost: High initial investment; economical at very high volumes
Decision Framework
Step 1: Assess Data Sensitivity and Compliance
Question: Can your data be processed on third-party infrastructure?
Scenario A: Data Cannot Leave Your Infrastructure
Requirements indicating this:
- Classified government/defense data
- Explicit data sovereignty mandates prohibiting cloud processing
- Air-gapped environment requirements
- Industry regulations prohibiting third-party access
- Extreme competitive sensitivity (trade secrets, M&A)
Your only option: Self-hosted deployment
Models available: Llama 4, Mistral, DeepSeek (open-source/downloadable models only)
Stop hereβproceed to Self-Hosted Implementation section below.
Scenario B: Cloud Processing Acceptable with Controls
Requirements:
- GDPR (EU data protection)
- HIPAA (US healthcare)
- Financial regulations (GLBA, PCI DSS)
- General corporate data governance
- Data residency preferences (but not absolute mandates)
Your options: Enterprise Cloud Platforms (Azure, AWS, Google) or Self-Hosted
Proceed to Step 2.
Scenario C: Standard Business Data (Low Sensitivity)
Characteristics:
- Public or internal-only data
- No regulatory restrictions on third-party processing
- General business content (non-confidential)
Your options: All deployment models (Direct API, Cloud Platforms, Self-Hosted)
Proceed to Step 2.
Step 2: Evaluate Volume and Cost
Question: What is your expected monthly token usage?
Low Volume (<10M tokens/month = <$100-300/month API cost)
Recommendation: Direct API
Rationale:
- Self-hosted infrastructure costs ($2-10K/month) far exceed API costs
- Enterprise platform premiums not justified at low volume
- Simplicity and speed matter more than cost optimization
Exception: Even at low volume, use Cloud Platform if compliance requires (HIPAA, data residency).
Medium Volume (10M-1B tokens/month = $100-10K/month API cost)
Recommendation: Direct API or Cloud Platform based on other factors
Rationale:
- API costs meaningful but not prohibitive
- Cloud platform premium (typically 10-30% over direct API) justified for:
- Enterprise compliance needs
- Integration with cloud infrastructure
- Need for unified governance
- Self-hosted not yet economical (unless specific constraints require it)
Decision factors:
- Compliance needs β Cloud Platform
- Cost-sensitive, no compliance requirements β Direct API
- Existing cloud investment β Cloud Platform
High Volume (>1B tokens/month = >$10K/month API cost)
Recommendation: Evaluate self-hosted alongside Cloud Platforms
Rationale:
- API costs substantial ($10K-100K+/month)
- Self-hosted infrastructure investment justifiable
- Break-even typically at $100-300/day in API costs (~400K predictions/month)
Calculate TCO:
API (e.g., Gemini Flash at $0.075/$0.30 per 1M tokens):
- 1B tokens/month input: $75
- 1B tokens/month output: $300
- Total: $375/month
Self-Hosted (e.g., Llama 4 on cloud GPU):
- GPU cloud VMs: $2,000-2,500/month
- Engineering (0.5 FTE): $4,000-7,000/month
- Total: $6,000-9,500/month
At this volume, API still cheaper. Self-hosting makes sense at 5-10x this volume or when API options eliminated by other constraints.
Very High Volume (>10B tokens/month): Self-hosted becomes economically attractive. Investment in infrastructure and team justified by savings.
Step 3: Assess Technical Capability
Question: Do you have AI/ML infrastructure expertise?
Limited Technical Capability
Characteristics:
- No dedicated ML engineering team
- Limited cloud infrastructure experience
- Small or no DevOps team
Recommendation: Direct API or Cloud Platform with managed services
Rationale:
- Self-hosting requires significant expertise (ML ops, GPU infrastructure, model serving)
- Managed services minimize operational burden
- Cloud platforms abstract complexity while providing controls
Choose Direct API if: Cost-sensitive, low compliance needs Choose Cloud Platform if: Enterprise requirements, integration needs
Moderate Technical Capability
Characteristics:
- Cloud infrastructure team exists
- DevOps capabilities
- Can learn ML-specific tools
- No dedicated ML engineers (yet)
Recommendation: Cloud Platform
Rationale:
- Can leverage cloud’s managed AI services
- Build expertise gradually
- Cloud platform provides training wheels for eventually self-hosting if needed
Strong Technical Capability
Characteristics:
- Dedicated ML engineering team
- Proven experience with model deployment
- Strong DevOps and infrastructure capabilities
- GPU infrastructure experience
Recommendation: Self-hosted or Cloud Platform, based on other factors
Rationale:
- Have capability to self-host successfully
- Decision depends on cost, control priorities, and volume
- Can implement hybrid: self-hosted for volume, APIs for variety
Step 4: Infrastructure and Ecosystem
Question: What is your existing cloud infrastructure?
Heavily Microsoft-Centric
Indicators:
- Azure infrastructure
- Microsoft 365, Active Directory
- .NET development stack
Recommendation: Azure AI Foundry
Models Available:
- OpenAI (GPT-4, GPT-5, o-series) - primary partnership
- DeepSeek (R1)
- Llama, Mistral, and 1,800+ model catalog
Benefits:
- Unified Microsoft ecosystem
- Single procurement relationship
- Integrated billing, IAM, security
- Strong OpenAI relationship (latest models first)
Heavily AWS-Centric
Indicators:
- AWS infrastructure dominates
- Heavy use of Lambda, S3, DynamoDB
- AWS security/compliance frameworks
Recommendation: AWS Bedrock
Models Available:
- Claude (Anthropic) - primary partnership
- Llama, Cohere, AI21, Stability AI, Amazon Titan
- Multi-vendor model marketplace
Benefits:
- Deep AWS ecosystem integration
- Managed service simplicity
- Multiple model options
- Claude preferred for coding use cases
Note: For OpenAI models, use Azure OpenAI Service (not available on AWS).
Heavily Google Cloud-Centric
Indicators:
- Google Cloud Platform infrastructure
- BigQuery, Google Workspace
- Data-heavy ML workflows
Recommendation: Google Vertex AI
Models Available:
- Gemini (2.5 Pro, Flash) - primary offering
- Claude, Llama, Mistral via Model Garden
Benefits:
- Native Gemini access (1M context, multimodal)
- Strong MLOps capabilities
- Unified data and AI platform
- Best-in-class fine-tuning suite
Multi-Cloud or Cloud-Agnostic
Indicators:
- No dominant cloud provider
- Intentional multi-cloud strategy
- Avoiding vendor lock-in priority
Recommendation: Direct APIs or Self-Hosted (open-source models)
Rationale:
- Direct APIs avoid cloud platform lock-in
- Self-hosted Llama/Mistral provides maximum portability
- Can deploy across multiple clouds as needed
Hybrid Approach:
- Use each cloud’s native AI where already invested
- Maintain abstraction layer for model switching
Step 5: Compliance and Risk
Question: What are your regulatory and compliance requirements?
HIPAA (US Healthcare)
Requirement: Business Associate Agreement (BAA)
Options:
- β Azure OpenAI Service (OpenAI with BAA)
- β AWS Bedrock (Claude, others with BAA)
- β Google Vertex AI (Gemini with BAA)
- β Self-hosted (full control, you manage compliance)
- β Direct APIs (typically no BAA for direct relationships)
Recommendation: Use cloud platforms with BAA, not direct APIs
GDPR (EU Data Protection)
Requirement: EU data residency, Data Processing Agreement (DPA)
Options:
- β Mistral (European company, GDPR-native)
- β Cloud platforms in EU regions (Azure EU, AWS EU, Google EU)
- β Self-hosted in EU
- β³ Direct APIs with DPA (check data processing locations)
Recommendation:
- First choice: Mistral (European provider)
- Alternative: Cloud platforms deployed in EU regions
- Maximum control: Self-hosted in EU
Government / Defense
Requirement: FedRAMP, ITAR, classified data handling
Options:
- β Self-hosted on approved infrastructure
- β³ FedRAMP-certified cloud platforms (for appropriate classification levels)
- β Commercial APIs (typically prohibited)
Recommendation: Self-hosted for classified; FedRAMP cloud for unclassified government
Financial Services
Requirement: SOC 2, data controls, audit trails
Options:
- β All major cloud platforms (SOC 2 certified)
- β Self-hosted (full control)
- β³ Direct APIs (verify SOC 2 certification)
Recommendation: Cloud platforms for managed compliance; self-hosted for maximum control
Deployment Model Comparison Matrix
| Factor | Direct API | Azure AI Foundry | AWS Bedrock | Google Vertex AI | Self-Hosted |
|---|---|---|---|---|---|
| Setup Time | Hours-days | Days-weeks | Days-weeks | Days-weeks | Months |
| Initial Cost | Very low | Low-moderate | Low-moderate | Low-moderate | Very high |
| Ongoing Cost | Usage-based | Slightly higher than API | Slightly higher than API | Slightly higher than API | Fixed (infrastructure) |
| Data Control | Low | High | High | High | Maximum |
| Compliance | Limited | Excellent (BAA, HIPAA) | Excellent (BAA, HIPAA) | Excellent (BAA, HIPAA) | Full (you manage) |
| Scalability | Automatic | Automatic | Automatic | Automatic | Manual |
| Maintenance | Provider | Provider | Provider | Provider | You |
| Customization | Limited | Moderate | Moderate | High (fine-tuning) | Maximum |
| Model Selection | Single provider | 1,800+ models | Multi-vendor | Gemini + Model Garden | Open-source only |
| Vendor Lock-In | High (to model) | Moderate (to Azure) | Moderate (to AWS) | Moderate (to Google) | None |
| Support | Basic | Enterprise | Enterprise | Enterprise | Self-support |
Decision Tree Summary
START
β
ββ Data MUST stay on-premise?
β ββ YES β Self-Hosted (Llama, Mistral)
β ββ NO β Continue
β
ββ HIPAA/regulated healthcare?
β ββ YES β Cloud Platform with BAA (Azure/AWS/Google)
β ββ NO β Continue
β
ββ Volume > 10B tokens/month?
β ββ YES β Evaluate Self-Hosted (economical at scale)
β ββ NO β Continue
β
ββ Strong cloud investment?
β ββ Azure β Azure AI Foundry (OpenAI, DeepSeek)
β ββ AWS β AWS Bedrock (Claude primary)
β ββ Google β Vertex AI (Gemini primary)
β ββ None β Continue
β
ββ Volume < 10M tokens/month?
β ββ YES β Direct API (simplicity, low cost)
β ββ NO β Continue
β
ββ Compliance needs (GDPR, SOC 2)?
β ββ YES β Cloud Platform (managed compliance)
β ββ NO β Direct API (lowest cost)
Deployment Recommendations by Scenario
Scenario 1: Startup MVP (Seed Stage)
Context: Building quickly, limited budget, exploring use cases
Recommendation: Direct API (GPT-4o, Claude, or Gemini Flash)
Rationale:
- Speed to market critical
- Low volume (API costs minimal)
- No infrastructure team
- Can migrate later if needed
Model Choice:
- Quality-first: GPT-4o or Claude
- Cost-first: Gemini Flash or DeepSeek-V3
Scenario 2: Scale-Up (Series B, Growing Volume)
Context: Product-market fit achieved, scaling usage, need reliability
Recommendation: Cloud Platform (based on existing cloud investment)
Rationale:
- Volume increasing (API costs meaningful)
- Need enterprise SLA and support
- Growing compliance requirements
- Can leverage existing cloud relationship
Implementation:
- Azure if Microsoft-heavy
- AWS if AWS-heavy
- Google if data/ML-heavy on Google Cloud
Scenario 3: Enterprise (Global 2000)
Context: Multiple use cases, high volume, strict compliance, multi-cloud
Recommendation: Hybrid: Cloud Platforms + Self-Hosted
Strategy:
- Cloud platforms for managed critical workloads (customer-facing, mid-volume)
- Self-hosted Llama/Mistral for highest-volume or most sensitive data
- Direct APIs for experimentation and non-critical tools
Implementation:
- Azure AI Foundry: OpenAI for customer apps
- Self-hosted Llama 4: High-volume internal processing
- AWS Bedrock: Claude for coding workflows
- Gemini API: Multimodal experiments
Scenario 4: Regulated Industry (Healthcare, Finance, Government)
Context: Strict compliance, audit requirements, data sovereignty
Recommendation:
- Healthcare (HIPAA): Cloud Platform with BAA (Azure/AWS/Google)
- Finance: Cloud Platform or self-hosted
- EU: Mistral or cloud platforms in EU regions
- Defense/Classified: Self-hosted only
Critical: Verify BAA, data residency, and compliance certifications before deployment.
Scenario 5: High-Volume Cost Optimization
Context: Processing >10B tokens/month, cost is primary concern
Recommendation: Self-Hosted Llama 4 or Mistral
Rationale:
- API costs $10K-100K+/month
- Infrastructure investment (β¬2-2.5K/month GPU + engineering) cheaper at scale
- No per-token costs after infrastructure
- Can fine-tune for specific needs
Break-even: Typically 10-30x higher token throughput vs API pricing
Platform-Specific Guidance
When to Choose Azure AI Foundry
Best for:
- Microsoft-centric organizations
- Need OpenAI models with enterprise controls
- Want 1,800+ model catalog
- Require HIPAA compliance with OpenAI
- Already using Azure infrastructure
Models: OpenAI (primary), DeepSeek, Llama, Mistral, 1,800+ others
Strengths: Largest model catalog, OpenAI partnership, Microsoft ecosystem integration
When to Choose AWS Bedrock
Best for:
- AWS-centric organizations
- Claude preferred (best coding, nuanced responses)
- Multi-model strategy
- Serverless and managed services preference
Models: Claude (primary), Llama, Cohere, AI21, Stability AI, Amazon Titan
Strengths: Claude access, multi-vendor flexibility, deep AWS integration
Note: No OpenAI models (use Azure for GPT)
When to Choose Google Vertex AI
Best for:
- Google Cloud organizations
- Gemini preferred (1M context, multimodal, price-performance)
- Data-heavy ML workflows
- Advanced fine-tuning needs
Models: Gemini (primary), Claude, Llama, Mistral (via Model Garden)
Strengths: Best fine-tuning suite, Gemini 1M context, unified data+AI platform
When to Self-Host
Best for:
- Data cannot leave infrastructure (sovereignty, classification)
- Volume >10B tokens/month (economical at scale)
- Need full customization (fine-tuning, model modification)
- Avoiding vendor lock-in strategic priority
- Strong ML engineering capability exists
Models: Llama 4, Mistral, DeepSeek (open-source only)
Requirements: GPU infrastructure, ML ops expertise, ongoing maintenance
Cost Comparison at Different Volumes
Example: 100M Tokens/Month (50M input, 50M output)
Direct API (Gemini Flash):
- Input: 50M Γ $0.075 = $3.75
- Output: 50M Γ $0.30 = $15
- Total: $18.75/month
Cloud Platform Premium (~20% higher):
- ~$22.50/month
Self-Hosted (Llama 4 on cloud GPU):
- GPU VM: $2,000-2,500/month
- Engineering (0.25 FTE): $2,000-3,500/month
- Total: $4,000-6,000/month
Winner: Direct API (self-hosted 200x more expensive at this volume)
Example: 10B Tokens/Month (5B input, 5B output)
Direct API (Gemini Flash):
- Input: 5B Γ $0.075 = $375
- Output: 5B Γ $0.30 = $1,500
- Total: $1,875/month
Cloud Platform Premium (~20%):
- ~$2,250/month
Self-Hosted:
- GPU infrastructure (multiple): $5,000-7,000/month
- Engineering (0.5-1 FTE): $4,000-7,000/month
- Total: $9,000-14,000/month
Winner: Still API, but self-hosted gap narrowing. At 2-3x this volume, self-hosted becomes competitive.
Example: 100B Tokens/Month (50B input, 50B output)
Direct API (Gemini Flash):
- Input: 50B Γ $0.075 = $3,750
- Output: 50B Γ $0.30 = $15,000
- Total: $18,750/month
Self-Hosted:
- GPU infrastructure (scaled): $10,000-15,000/month
- Engineering (1-2 FTE): $8,000-14,000/month
- Total: $18,000-29,000/month
Winner: Competitive. Self-hosted now justifiable, especially for data sovereignty benefits. At higher volumes, self-hosted wins clearly.
Implementation Checklist
Direct API Deployment
- Select provider (OpenAI, Claude, Gemini, DeepSeek)
- Review terms of service and data usage policies
- Obtain API keys
- Implement authentication and rate limiting
- Set up billing alerts
- Test with sample requests
- Implement error handling and retries
- Monitor usage and costs
Cloud Platform Deployment
- Choose platform (Azure, AWS, Google)
- Provision AI service (AI Foundry, Bedrock, Vertex AI)
- Configure IAM and access controls
- Set up networking (VPCs, private endpoints if needed)
- Integrate with existing cloud services
- Configure monitoring and logging
- Establish cost controls and budgets
- Sign BAA if HIPAA required
- Verify compliance certifications
- Test deployment with sample workloads
Self-Hosted Deployment
- Select model (Llama 4, Mistral, DeepSeek)
- Provision GPU infrastructure (cloud VMs or on-premise)
- Install model serving framework (vLLM, TensorRT-LLM, Ollama)
- Deploy and test model
- Implement load balancing and scaling
- Set up monitoring (performance, errors, resource usage)
- Establish security controls (access, encryption)
- Plan update and maintenance procedures
- Train team on operations
- Document runbooks for common issues
Common Pitfalls to Avoid
Choosing self-hosted too early: Infrastructure costs far exceed API costs at low-medium volumes. Only self-host when volume justifies or constraints require.
Ignoring compliance until late: HIPAA, GDPR, data residency requirements eliminate or constrain deployment options. Address early.
Underestimating self-hosted operational burden: Self-hosting requires ongoing engineering timeβminimum 0.25-0.5 FTE, often more.
Not calculating full TCO: Compare apples-to-apples including infrastructure, engineering time, support, and opportunity costs.
Vendor lock-in without realizing: Deep cloud platform integration creates switching costs. Maintain abstraction layer if portability matters.
Direct API for regulated data: HIPAA, classified data, strict GDPR often require cloud platforms with BAAs or self-hosting, not direct APIs.
Summary
Choose Direct API when:
- Volume low (<10M tokens/month)
- No strict compliance requirements
- Speed and simplicity prioritized
- Limited technical resources
Choose Cloud Platform when:
- HIPAA, GDPR, or compliance frameworks required
- Medium-high volume (10M-10B tokens/month)
- Enterprise support and SLA needed
- Existing cloud investment to leverage
Choose Self-Hosted when:
- Data must stay on-premise (sovereignty, classification)
- Very high volume (>10-50B tokens/month)
- Need maximum customization
- Strong ML ops capability exists
For most organizations: Start with Direct API (learn fast, low risk), graduate to Cloud Platforms as volume and compliance needs grow, consider self-hosted only when volume justifies or constraints require.
The optimal strategy is often hybrid: Use different deployment models for different use cases based on sensitivity, volume, and requirements.