How Sentra Built a Data Security Platform for the AI Era

Amazon S3 is one of the most widely used cloud storage services in the world, and with that scale comes real security responsibility. Misconfigured buckets remain a leading cause of sensitive data exposure in cloud environments, from accidentally public objects to overly permissive policies that go unnoticed for months. Whether you're hosting static assets, storing application data, or archiving compliance records, getting S3 bucket security right is not optional. This guide covers foundational defaults, policy configurations, and practical checklists to give you an actionable reference as of early 2026.

How S3 Bucket Security Works by Default

A common misconception is that S3 buckets are inherently risky. In reality, all S3 buckets are private by default. When you create a new bucket, no public access is granted, and AWS automatically enables Block Public Access settings at the account level.

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Access is governed by a layered permission model where an explicit Deny always overrides an Allow, regardless of where it's defined. Understanding this hierarchy is the foundation of any secure configuration:

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• IAM identity-based policies, control what actions a user or role can perform
• Bucket resource-based policies, define who can access a specific bucket and under what conditions
• Access Control Lists (ACLs), legacy object-level permissions (AWS now recommends disabling these entirely)
• VPC endpoint policies, restrict which buckets and actions are reachable from within a VPC

AWS recommends setting S3 Object Ownership to "bucket owner enforced," which disables ACLs. This simplifies permission management significantly, instead of managing object-level ACLs across millions of objects, all access flows through bucket policies and IAM, which are far easier to audit.

AWS S3 Security Best Practices

A defense-in-depth approach means layering multiple controls rather than relying on any single setting. Here is the current AWS-recommended baseline:

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S3 Bucket Policy Examples for Common Security Scenarios

Bucket policies are JSON documents attached directly to a bucket that define who can access it and under what conditions. Below are the most practically useful examples.

Enforce HTTPS-Only Access

{
  "Version": "2012-10-17",
  "Statement": [{
    "Sid": "RestrictToTLSRequestsOnly",
    "Effect": "Deny",
    "Principal": "*",
    "Action": "s3:*",
    "Resource": [
      "arn:aws:s3:::your-bucket-name",
      "arn:aws:s3:::your-bucket-name/*"
    ],
    "Condition": { "Bool": { "aws:SecureTransport": "false" } }
  }]
}

Deny Unencrypted Uploads (Enforce KMS)

{

"Version": "2012-10-17",

"Statement": [{

"Sid": "DenyObjectsThatAreNotSSEKMS",

"Principal": "*",

"Effect": "Deny",

"Action": "s3:PutObject",

"Resource": "arn:aws:s3:::your-bucket-name/*",

"Condition": {

"Null": {

"s3:x-amz-server-side-encryption-aws-kms-key-id": "true" } } }]}

Other Common Patterns

• Restrict to a specific VPC endpoint: Use the aws:sourceVpce condition key to ensure the bucket is only reachable from a designated private network.
• Grant CloudFront OAI access: Allow only the Origin Access Identity principal, keeping objects private from direct URL access while serving them through the CDN.
• IP-based restrictions: Use NotIpAddress with aws:SourceIp to deny requests from outside a trusted CIDR range.

Always use "Version": "2012-10-17" and validate policies through IAM Access Analyzer before deployment to catch unintended access grants.

Enforcing SSL with the s3-bucket-ssl-requests-only Policy

Forcing all S3 traffic over HTTPS is one of the most straightforward, high-impact controls available. The AWS Config managed rule s3-bucket-ssl-requests-only checks whether your bucket policy explicitly denies HTTP requests, flagging non-compliant buckets automatically.

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The policy evaluates the aws:SecureTransport condition key. When a request arrives over plain HTTP, this key evaluates to false, and the Deny statement blocks it. This applies to all principals, AWS services, cross-account roles, and anonymous requests alike. Adding the HTTPS-only Deny statement shown in the policy examples section above satisfies both the AWS Config rule and common compliance requirements under PCI-DSS and HIPAA.

Using an S3 Bucket Policy Generator Safely

The AWS Policy Generator is a useful starting point, but generated policies require careful review before going into production. Follow these steps:

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• Select "S3 Bucket Policy" as the policy type, then fill in the principal, actions, resource ARN, and conditions (e.g., aws:SecureTransport or aws:SourceIp).
• Check for overly broad principals, avoid "Principal": "*" unless intentional.
• Verify resource ARNs are scoped correctly (bucket-level vs. object-level).
• Use IAM Access Analyzer's "Preview external access" feature to understand the real-world effect before saving.

The generator is a scaffold, security judgment still applies. Never paste generated JSON directly into production without review.

S3 Bucket Security Checklist

Use this consolidated checklist to audit any S3 bucket configuration:

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How Sentra Strengthens S3 Bucket Security at Scale

Applying the right bucket policies and IAM controls is necessary, but at enterprise scale, knowing which buckets contain sensitive data, how that data moves, and who can access it becomes the harder problem. This is where cloud data exposure typically occurs: not from a single misconfigured bucket, but from data sprawl across hundreds of buckets that no one has a complete picture of.

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Sentra discovers and classifies sensitive data at petabyte scale directly within your environment, data never leaves your control. It maps data movement across S3, identifies shadow data and over-permissioned buckets, and enforces data-driven guardrails aligned with compliance requirements. For organizations adopting AI, Sentra provides the visibility needed to ensure sensitive training data or model outputs in S3 are properly governed. Eliminating redundant and orphaned data typically reduces cloud storage costs by around 20%.

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S3 bucket security is not a one-time configuration task. It's an ongoing practice spanning access control, encryption, network boundaries, monitoring, and data visibility. The controls covered here, from enforcing SSL and disabling ACLs to using policy generators safely and maintaining a security checklist, give you a comprehensive framework. As your environment grows, pairing these technical controls with continuous data discovery ensures your security posture scales with your data, not behind it.

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Most security architects didn’t sign up to be AI product managers. Yet that’s what Copilot and Gemini rollouts feel like: “We want this in every business unit, as soon as possible. Make sure it’s safe.”

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If you’re being asked to recommend or validate a DSPM platform, or to justify why your existing DLP stack is or isn’t enough, you need a realistic, vendor‑agnostic set of criteria that maps to how Copilot and Gemini actually work.

This guide is written from that perspective: what matters when you evaluate DSPM and DLP for AI assistants, what’s table stakes vs. differentiating, and what you should ask every vendor before you bring them to your steering committee.

1. Start with the AI use cases you actually have

Before you look at tools, clarify your Copilot and/or Gemini scope:

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• Are you rolling out Microsoft 365 Copilot to a pilot group, or planning an org‑wide deployment?
• Are you enabling Gemini in Workspace only, or also Gemini for dev teams (Vertex AI, custom LLM apps, RAG)?
• Do you have existing AI initiatives (third‑party SaaS copilots, homegrown assistants) that will access M365 or Google data?

This matters because different tools have very different coverage:

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• Some are M365‑centric with shallow Google support.
• Others focus on cloud infrastructure and data warehouses, and barely touch SaaS.
• Very few provide deep, in‑environment visibility across both SaaS and cloud platforms, which is what you need if Copilot/Gemini are just the tip of your AI iceberg.

Define the boundary first; evaluate tools second.

2. Non‑negotiable DSPM capabilities for Copilot and Gemini

When Copilot and Gemini are in scope, “generic DSPM” is not enough. You need specific capabilities that touch how those assistants see and use data.

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2.1 Native visibility into M365 and Workspace

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At minimum, a viable DSPM platform must:

• Discover and classify sensitive data across SharePoint, OneDrive, Exchange, Teams and Google Drive / shared drives.
• Understand sharing constructs (public/org‑wide links, external guests, shared drives) and relate them to data sensitivity.
• Support unstructured formats including Office docs, PDFs, images, and audio/video files.

Ask vendors:

• “Show me, live, how you discover sensitive data in Teams chats and OneDrive/Drive folders that are Copilot/Gemini‑accessible.”
• “Show me how you handle PDFs, audio, and meeting recordings - not just Word docs and spreadsheets.”

Sentra, for example, was explicitly built to discover sensitive data across IaaS, PaaS, SaaS, and on‑prem, and to handle formats like audio/video and complex PDFs as first‑class sources.

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2.2 In‑place, agentless scanning

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For many organizations, it’s now a hard requirement that data never leaves their cloud environment for scanning. Evaluate if the vendor scan in‑place within your tenants, using cloud APIs and serverless functions or do they require copying data or metadata into their infrastructure?

Sentra’s architecture is explicitly “data stays in the customer environment”, which is why large, regulated enterprises have standardized on it.

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2.3 AI‑grade classification accuracy and context

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Copilot and Gemini are only as safe as your labels and identity model. That requires:

• High‑accuracy classification (>98%) across structured and unstructured content.
• The ability to distinguish synthetic vs. real data and to attach rich context: department, geography, business function, sensitivity, owner.

Ask:

• “How do you measure classification accuracy, and on what datasets?”
• “Can you show me how your platform treats, for example, a Zoom recording vs. a scanned PDF vs. a CSV export?”

Sentra uses AI‑assisted models and granular context classes at both file and entity level, which is why customers report >98% accuracy and trust the labels enough to drive enforcement.

3. Evaluating DLP in an AI‑first world

Most enterprises already have DLP: endpoint, email, web, CASB. The question is whether it can handle AI assistants and the honest answer is that DLP alone usually can’t, because:

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• It operates blind to real data context, relying on regex and static rules.
• It usually doesn’t see unstructured SaaS stores or AI outputs reliably.
• Policies quickly become so noisy that they get weakened or disabled.

The evaluation question is not “DLP or DSPM?” It’s:

“Which DSPM platform can make my DLP stack effective for Copilot and Gemini, without a rip‑and‑replace?”

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Look for:

• Tight integration with Microsoft Purview (for MPIP labels and Copilot DLP) and, where relevant, Google DLP.
• The ability to auto‑apply and maintain labels that DLP actually enforces.
• Support for feeding data context (sensitivity + business impact + access graphs) into enforcement decisions.

Sentra becomes the single source of truth for sensitivity and business impact that existing DLP tools rely on.

4. Scale, performance, and operating cost

AI rollouts increase data volumes and usage faster than most teams expect. A DSPM that looks fine on 50 TB may struggle at 5 PB.

Evaluation questions:

• “What’s your largest production deployment by data volume? How many PB?”
• “How long does an initial full scan take at that scale, and what’s the recurring scan pattern?”
• “What does cloud compute spend look like at 10 PB, 50 PB, 100 PB?”

Sentra customer tests prove ability to scan 9 PB in under 72 hours at 10–1000x greater scan efficiency than legacy platforms, with projected scanning of 100 PB at roughly $40,000/year in cloud compute.

If a vendor can’t answer those questions quantitatively, assume you’ll be rationing scans, which undercuts the whole point of DSPM for AI.

5. Governance, reporting, and “explainability” for architects

Your stakeholders, security leadership, compliance, boards, will ask three things:

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1. “Where, exactly, can Copilot and Gemini see regulated data?”
2. “How do we know permissions and labels are correct?”
3. “Can you prove we’re compliant right now, not just at audit time?”

A strong DSPM platform helps you answer those questions without building custom reporting in a SIEM:

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• AI‑specific risk views that show AI assistants, datasets, and identities in one place.
• Compliance mappings to frameworks like GLBA, SOX, FFIEC, GDPR, HIPAA, PCI DSS, and state privacy laws.
• Executive‑ready summaries of AI‑related data risk and progress over time (e.g., percentage of regulated data coverage, number of Copilot‑accessible high‑risk stores before vs. after remediation).

Sentra’s AI Data Readiness and continuous compliance materials give a good template for what “explainable DSPM” looks like in practice.

6. Putting it together: A concise RFP checklist

When you boil it down, your evaluation criteria for DSPM/DLP for Copilot and Gemini should include:

• In‑place, multi‑cloud/SaaS discovery with strong M365 and Workspace coverage
• Proven high‑accuracy classification and rich business context for unstructured data
• Identity‑to‑data mapping with least‑privilege insights
• Native integrations with MPIP/Purview and Google DLP, with label automation
• Real‑world scale (PB‑level) and quantified cloud cost
• AI‑aware risk views, compliance mappings, and reporting

Use those as your “table stakes” in RFPs and technical deep dives. You can add vendor‑specific questions on top, but if a tool can’t clear this bar, it will not make Copilot and Gemini genuinely safe - it will just give you more dashboards.

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As enterprises scale cloud adoption and AI integration in 2026, protecting sensitive data across complex environments has never been more critical. Data sprawls across IaaS, PaaS, SaaS, and on-premise systems, creating blind spots that regulators and threat actors are eager to exploit. Cloud data protection solutions have evolved well beyond simple backup and recovery, today's leading platforms combine AI-powered discovery, real-time data movement tracking, access control analysis, and compliance support into unified architectures. Choosing the right solution determines how confidently your organization can operate in the cloud.

Best Cloud Data Protection Solutions

The market spans two distinct categories, each addressing different layers of cloud security.

Backup, Recovery, and Data Resilience

• Druva Data Security Cloud, Rated 4.9 on Gartner with "Customer's Choice" recognition. Centralized backup, archival, disaster recovery, and compliance across endpoints, servers, databases, and SaaS in hybrid/multicloud environments.
• Cohesity DataProtect, Rated 4.7. Automates backup and recovery across on-premises, cloud, and hybrid infrastructures with policy-based management and encryption.
• Veeam Data Platform, Rated 4.6. Combines secure backup with intelligent data insights and built-in ransomware defenses.
• Rubrik Security Cloud, Integrates backup, recovery, and automated policy-driven protection against ransomware and compliance gaps across mixed environments.
• Dell Data Protection Suite, Rated 4.7. Addresses data loss, compliance, and ransomware through backup, recovery, encryption, and deduplication.

Cloud-Native Security and DSPM

• Sentra, Discovers and governs sensitive data at petabyte scale inside your own environment, with agentless architecture, real-time data movement tracking, and AI-powered classification.
• Wiz, Agentless scanning, real-time risk prioritization, and automated mapping to 100+ regulatory frameworks across multi-cloud environments.
• BigID, Comprehensive data discovery and classification with automated remediation, including native Snowflake integration for dynamic data masking.
• Palo Alto Networks Prisma Cloud, Scalable hybrid and multi-cloud protection with AI analytics, DLP, and compliance enforcement throughout the development lifecycle.
• Microsoft Defender for Cloud, Integrated multi-cloud security with continuous vulnerability assessments and ML-based threat detection across Azure, AWS, and Google Cloud.

What Users Say About These Platforms

User feedback as of early 2026 reveals consistent themes across the leading platforms.

Sentra

Pros:

• Data discovery accuracy and automation capabilities are standout strengths
• Compliance and audit preparation becomes significantly smoother, one user described HITECH audits becoming "a breeze"
• Classification engine reduces manual effort and improves overall efficiency

Cons:

• Initial dashboard experience can feel overwhelming
• Some limitations in on-premises coverage compared to cloud environments
• Third-party sync delays flagged by a subset of users

Rubrik

Pros:

• Strong visibility across fragmented environments with advanced encryption and data auditing
• Frequently described as a top choice for cybersecurity professionals managing multi-cloud

Cons:

• Scalability limitations noted by some reviewers
• Integration challenges with mature SaaS solutions

Wiz

Pros:

• Agentless deployment and multi-cloud visibility surface risk context quickly

Cons:

• Alert overload and configuration complexity require careful tuning

BigID

Pros:

• Comprehensive data discovery and privacy automation with responsive customer service

Cons:

• Delays in technical support and slower DSAR report generation reported

As of February 2026, none of these platforms have published Trustpilot scores with sufficient review counts to generate a verified aggregate rating.

How Leading Platforms Compare on Core Capabilities

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Cloud Data Security Best Practices

Selecting the right platform is only part of the equation. How you configure and operate it determines your actual security posture.

• Apply the shared responsibility model correctly. Cloud providers secure infrastructure; you are responsible for your data, identities, and application configurations.
• Enforce least-privilege access. Use role-based or attribute-based access controls, require MFA, and regularly audit permissions.
• Encrypt data at rest and in transit. Use TLS 1.2+ and manage keys through your provider's KMS with regular rotation.
• Implement continuous monitoring and logging. Real-time visibility into access patterns and anomalous behavior is essential. CSPM and SIEM tools provide this layer.
• Adopt zero-trust architecture. Continuously verify identities, segment workloads, and monitor all communications regardless of origin.
• Eliminate shadow and ROT data. Redundant, obsolete, and trivial data increases your attack surface and storage costs. Automated identification and removal reduces risk and cloud spend.
• Maintain and test an incident response plan. Documented playbooks with defined roles and regular simulations ensure rapid containment.

Top Cloud Security Tools for Data Protection

Beyond the major platforms, several specialized tools are worth integrating into a layered defense strategy:

• Check Point CloudGuard, ML-powered threat prevention for dynamic cloud environments, including ransomware and zero-day mitigation.
• Trend Micro Cloud One, Intrusion detection, anti-malware, and firewall protections tailored for cloud workloads.
• Aqua Security, Specializes in containerized and cloud-native environments, integrating runtime threat prevention into DevSecOps workflows for Kubernetes, Docker, and serverless.
• CrowdStrike Falcon, Comprehensive CNAPP unifying vulnerability management, API security, and threat intelligence.
• Sysdig, Secures container images, Kubernetes clusters, and CI/CD pipelines with runtime threat detection and forensic analysis.
• Tenable Cloud Security, Continuous monitoring and AI-driven threat detection with customizable security policies.

Complementing these tools with CASB, DSPM, and IAM solutions creates a layered defense addressing discovery, access control, threat detection, and compliance simultaneously.

How Sentra Approaches Cloud Data Protection

For organizations that need to go beyond backup into true cloud data security, Sentra offers a fundamentally different architecture. Rather than routing data through an external vendor, Sentra scans in-place, your sensitive data never leaves your environment. This is particularly relevant for regulated industries where data residency and sovereignty are non-negotiable.

Key Capabilities

• Purely agentless onboarding, No sidecars, no agents, zero impact on production latency
• Unified view across IaaS, PaaS, SaaS, and on-premise file shares with continuous discovery and classification at petabyte scale
• DataTreks™, Creates an interactive map of your data estate, tracking how sensitive data moves through ETL processes, migrations, backups, and AI pipelines
• Toxic combination detection, Correlates data sensitivity with access controls, flagging high-sensitivity data behind overly permissive policies
• AI governance guardrails, Prevents unauthorized AI access to sensitive data as enterprises integrate LLMs and other AI systems

In documented deployments, Sentra has processed 9 petabytes in under 72 hours and analyzed 100 petabytes at approximately $40,000. Its data security posture management approach also eliminates shadow and ROT data, typically reducing cloud storage costs by around 20%.

Choosing the Right Fit

The right solution depends on the problem you're solving. If your primary need is backup, recovery, and ransomware resilience, Druva, Veeam, Cohesity, and Rubrik are purpose-built for that. If your challenge is discovering where sensitive data lives and how it moves, particularly for AI adoption or regulatory audits, DSPM-focused platforms like Sentra and BigID are better aligned. For automated compliance mapping across GDPR, HIPAA, and the EU AI Act, Wiz's 100+ built-in framework assessments offer a clear advantage.

Most mature security programs layer multiple tools: a backup platform for resilience, a DSPM solution for data visibility and governance, and a CNAPP or CSPM tool for infrastructure-level threat detection. The key is ensuring these tools share context rather than creating additional silos. As data environments grow more complex and AI workloads introduce new vectors for exposure, investing in cloud data protection solutions that provide genuine visibility, not just coverage, will define which organizations operate with confidence.

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