Cloud security architecture is the structured framework of policies, controls, and technologies that protect your data, applications, and infrastructure running on cloud platforms like AWS, Azure, and Google Cloud. With Indian businesses rapidly migrating to cloud — Nasscom estimates 70%+ of Indian enterprises now use at least one cloud platform — understanding the shared responsibility model and implementing proper security controls is critical, because the cloud provider secures the infrastructure but you are responsible for securing everything you put on it.
Last updated October 2026
What Is the Shared Responsibility Model?
Every major cloud provider operates on a shared responsibility model:
| Layer | IaaS (EC2, VMs) | PaaS (RDS, App Service) | SaaS (Office 365, Salesforce) |
|---|---|---|---|
| Physical infrastructure | Provider | Provider | Provider |
| Network controls | Provider + You | Provider | Provider |
| Operating system | You | Provider | Provider |
| Applications | You | You | Provider |
| Data | You | You | You |
| Identity and access | You | You | You |
The critical takeaway: your data and access controls are always your responsibility, regardless of cloud model.
How to Secure Identity and Access Management (IAM)
Compromised credentials cause 60%+ of cloud breaches. IAM is your first and most important defense layer:
Essential IAM Controls
- Root account lockdown: Never use the root/owner account for daily operations. Create individual IAM users with specific permissions. Store root credentials in a hardware security module or secure vault.
- Enforce MFA everywhere: All human users must use MFA. For AWS, require MFA for console access and for sensitive API calls (like deleting S3 buckets or modifying IAM policies).
- Principle of least privilege: Grant only the minimum permissions needed. Use AWS IAM Access Analyzer, Azure AD Privileged Identity Management, or GCP IAM Recommender to identify and remove excessive permissions.
- Service accounts: Use dedicated service accounts for applications, not personal user credentials. Rotate service account keys regularly (every 90 days maximum). Prefer short-lived tokens (AWS STS, GCP workload identity) over long-lived keys.
- SSO integration: Integrate cloud IAM with your corporate identity provider (Azure AD, Okta, Google Workspace) for centralized user management and automatic deprovisioning when employees leave.
How to Secure Cloud Networking
Network Architecture Best Practices
- VPC/VNet design: Create separate VPCs (AWS), VNets (Azure), or VPC networks (GCP) for production, staging, and development. Never mix workload types in the same network.
- Subnet segmentation: Place web servers in public subnets, application servers in private subnets, and databases in isolated subnets with no internet access.
- Security groups: Apply security groups (cloud firewalls) with deny-all-by-default rules. Open only specific ports needed, and restrict source IPs wherever possible.
- No public database access: Databases should never have public IP addresses. Access them only through private subnets, VPN, or bastion hosts.
- VPN or Private Link: Connect your office network to cloud via site-to-site VPN or dedicated connections (AWS Direct Connect from Mumbai, Azure ExpressRoute). Use private endpoints for accessing cloud services without traversing the public internet.
DDoS Protection
- AWS Shield Standard (free) provides basic DDoS protection; Shield Advanced (from $3,000/month) provides enhanced protection with 24/7 DDoS Response Team.
- Azure DDoS Protection Standard provides network-level protection.
- Cloudflare (free tier) in front of your cloud infrastructure handles most volumetric DDoS attacks.
How to Protect Data in the Cloud
Encryption
- At rest: Enable encryption for all storage services. AWS S3 default encryption (SSE-S3 or SSE-KMS), Azure Storage encryption, GCP default encryption. Use customer-managed keys (CMKs) via AWS KMS, Azure Key Vault, or GCP Cloud KMS for sensitive data.
- In transit: Enforce TLS 1.2+ for all connections. Use VPC endpoints to keep data traffic within the cloud provider’s network.
- In use: For highly sensitive workloads, consider confidential computing (AWS Nitro Enclaves, Azure Confidential VMs, GCP Confidential VMs) which encrypts data even while being processed.
Data Classification and Loss Prevention
- Classify data into tiers: Public, Internal, Confidential, Restricted.
- Apply different security controls per tier (encryption keys, access controls, monitoring).
- Enable cloud-native DLP: AWS Macie (scans S3 for PII/sensitive data), Azure Information Protection, GCP Cloud DLP.
- For Indian businesses: identify data subject to DPDP Act 2023, IT Act Section 43A, and RBI data localization requirements.
Cloud Security Monitoring and Compliance
Continuous Monitoring
- Cloud-native SIEM: AWS CloudTrail + GuardDuty, Azure Sentinel, GCP Security Command Center. These detect suspicious activities like unusual API calls, cryptocurrency mining, or data exfiltration.
- Configuration auditing: AWS Config, Azure Policy, GCP Organization Policy — continuously check whether resources comply with your security policies and alert on violations.
- Cost monitoring: Unusual cost spikes often indicate compromised accounts (attackers spin up cryptocurrency mining instances). Set billing alerts at 120% of expected monthly cost.
Compliance Frameworks for Indian Businesses
- DPDP Act 2023: India’s data protection law requires consent management, data minimization, and breach notification within 72 hours.
- RBI Guidelines: Financial data must be stored in India. Use AWS Mumbai (ap-south-1), Azure Central India, or GCP Mumbai regions.
- ISO 27001: The most widely recognized information security certification for Indian IT companies.
- SOC 2: Required by many international clients before engaging Indian IT service providers.
The MAD’s cyber security practice helps Indian businesses design and implement cloud security architectures across AWS, Azure, and GCP. From startup cloud setups to enterprise multi-cloud security strategies, we provide security assessments starting at ₹75,000. Book a cloud security assessment.
Frequently Asked Questions
Which cloud provider is the most secure for Indian businesses?
All three major providers (AWS, Azure, GCP) have robust security infrastructure and India-region data centers. The security difference comes from how you configure and use them, not the platform itself. AWS has the most mature security toolset, Azure integrates best with Microsoft environments (Active Directory, Office 365), and GCP leads in container security (GKE) and data analytics security.
How much does cloud security cost for a typical Indian startup?
Basic cloud security (IAM best practices, encryption, security groups, CloudTrail logging) adds 5-10% to your cloud bill. Advanced security (SIEM, WAF, DDoS protection, compliance monitoring) adds 15-25%. For a startup spending ₹1 lakh/month on AWS, budget ₹10,000-25,000/month for security tooling, plus one-time architecture consulting.
Is multi-cloud more secure than single-cloud?
Multi-cloud adds resilience against provider-specific outages but increases security complexity. Each cloud has different security tools, IAM models, and configurations. Most Indian businesses should master security on one platform before adding another. Multi-cloud makes sense for large enterprises with specific workload requirements (e.g., Azure for Microsoft ecosystem, AWS for everything else).
How do I ensure RBI compliance for financial data in the cloud?
Use only India-region cloud services (AWS ap-south-1, Azure Central India/South India, GCP asia-south1). Implement data residency controls using AWS Organization SCPs, Azure Policy, or GCP Organization Policies to prevent data from being stored or processed outside India. Encrypt all financial data with customer-managed keys and maintain audit logs for all access.
What certifications should our cloud security team hold?
Prioritize: AWS Certified Security – Specialty, Azure Security Engineer Associate, or Google Professional Cloud Security Engineer, depending on your platform. For vendor-neutral knowledge, CCSP (Certified Cloud Security Professional) and CCSK (Certificate of Cloud Security Knowledge) are widely recognized. For Indian professionals, these certifications typically require ₹30,000-50,000 in exam and preparation costs.
