Quantum Computing Threats: How to Prepare Your Encryption Strategy

Quantum Computing Threats: How to Prepare Your Encryption Strategy

Quantum computing threats are the risk that future quantum computers will break the public-key cryptography protecting most digital data today. To prepare, organizations must inventory where vulnerable algorithms like RSA, ECC, and Diffie-Hellman are used, deploy post-quantum cryptography where possible, and build crypto agility so algorithms can be swapped without rewriting systems. The most urgent action is mitigating "Harvest Now, Decrypt Later" attacks, where encrypted data stolen today can be decrypted once quantum machines mature.

Introduction and Methodology

This article analyzes guidance from three major technology providers—Google Cloud, Accenture, and Palo Alto Networks—to build a practical benchmark for post-quantum readiness. Our methodology involved extracting common recommendations, identifying phased approaches, and synthesizing them into a unified framework. We examined each source for specific actions, metrics, and strategic priorities. Where sources disagreed or emphasized different aspects, we noted the divergence. The goal is to provide information security professionals with a data-driven, actionable roadmap.

The evidence base consists of publicly available roadmaps and blog posts from these vendors, all published as part of their thought leadership on post-quantum cryptography. No proprietary data was used. The analysis focuses on recurring themes and concrete steps that security teams can implement. We also identify gaps and areas where organizational context will determine the best path.

Benchmark Metrics Summary

The table below summarizes the key benchmark metrics for post-quantum readiness, derived from the three sources.

These metrics provide a baseline for assessing organizational readiness. Each will be discussed in detail.

Why Are Quantum Computing Threats Different From Traditional Cyber Risks?

Traditional cyber threats exploit software flaws or human error. Quantum computing threats are fundamentally different because they target mathematical foundations. Public-key algorithms like RSA and ECC rely on the difficulty of factoring large numbers or solving discrete logarithms. A sufficiently powerful quantum computer running Shor's algorithm could solve these problems efficiently, rendering those algorithms obsolete.

The timeline is uncertain, but the risk is not speculative. Attackers can already steal encrypted data today and store it until quantum computers are capable of decryption. This is known as "Harvest Now, Decrypt Later" (SNDL). For data with long confidentiality requirements—such as health records, financial data, or state secrets—this is an immediate concern. Google Cloud explicitly identifies mitigating SNDL as a primary goal.

Another distinction is that quantum threats also affect digital signatures. A quantum computer could forge signatures, undermining trust in identity and data integrity. So the threat is twofold: confidentiality and integrity. Security teams must address both.

Key Findings Summary

Our analysis reveals that leading organizations approach quantum readiness in phases. First, they inventory cryptographic assets. Second, they update software stacks to support post-quantum algorithms. Third, they validate performance and interoperability. Fourth, they build crypto agility into their architecture.

A critical finding is that crypto agility is not optional; it is the cornerstone of long-term security. Accenture describes a "crypto-agile orchestration layer" that allows algorithm switching without disrupting systems. Google Cloud emphasizes enhancing foundational capabilities for cryptographic agility. Palo Alto Networks recommends deploying inline cipher translation to protect legacy systems without code rewrites.

Another key finding is that executive alignment is essential. Accenture stresses that success depends on aligning strategy and execution at the highest levels of leadership, including the board. Funding and resources must be allocated early to avoid delays.

Finally, the performance impact of PQC is a real consideration. Palo Alto Networks recommends conducting high-throughput pilots to measure the "performance tax". This is a nuance often overlooked in theoretical discussions.

Detailed Results: What Steps Do Leading Vendors Recommend?

We extracted specific actions from each source and mapped them to a common framework.

Google Cloud's Roadmap

Google Cloud outlines three priorities: mitigating SNDL, ensuring integrity against forgery, and enhancing crypto agility. Their recommended steps are:

1. Inventory: Identify cryptographic resources using Cloud Asset Inventory and third-party tools like Wiz's cryptography and PQC readiness. This mapping helps define and prioritize the migration backlog.
2. Update: Ensure development and SRE teams use software that supports PQC algorithms such as BoringSSL, Chrome, and SDKs. This prepares internal workflows to negotiate quantum-safe connections by default.
3. Validate: Test existing applications using quantum-safe APIs. This step ensures compatibility and performance before full rollout.

Google Cloud's approach is cloud-centric but applicable to any organization using similar services.

Accenture's 8 Steps

Accenture recommends a phased roadmap that prioritizes quick wins while planning long-term initiatives. Key actions include:

• Deploy quantum-safe patches and update vulnerability management systems.
• Review vendor PQC support.
• Upgrade operational technology and secure high-risk connections.
• Build an organization-wide roadmap and governance model with executive support.
• Quantify the effort required to shift to PQC and educate stakeholders.
• Integrate the transition into existing projects and plan funding early.
• Treat post-quantum security as an ongoing discipline, not a one-time project.
• Put a crypto-agile orchestration layer in place to switch algorithms, enforce policies, and stay aligned with evolving standards.

Accenture emphasizes that this is a continuous journey, not a destination.

Palo Alto Networks' Operational Focus

Palo Alto Networks provides tactical guidance for managing the transition:

• Inventory Cryptographic Dependencies: Identify systems handling high-value traffic without quantum-resistant handshakes.
• Map Cryptographic Usage: Build an inventory of where quantum-vulnerable algorithms (RSA, ECC, Diffie-Hellman) are active.
• Audit Priority Systems: Focus on internet-facing applications, VPNs, TLS/mTLS traffic, APIs, identity systems, and code-signing environments.
• Deploy Inline Cipher Translation: Use firewalls as post-quantum proxies to shield legacy applications and IoT devices from SNDL without code rewrites.
• Automate Hybrid Remediation: Roll out automated certificate rotation and hybrid VPN tunnels for quantum-resistant communication.
• Measure Performance Tax: Conduct high-throughput pilots on production-adjacent systems to quantify PQC's impact.

This operational focus complements the strategic guidance from Google Cloud and Accenture.

Analysis by Category: A Framework for Prioritization

We synthesized the above into five categories of readiness. Each category includes a description, key actions, and metrics to track.

1. Cryptographic Discovery and Inventory

Understanding where cryptography is used is the foundation. You cannot protect what you don't know you have. All three sources emphasize inventory as a first step. Google Cloud suggests using Cloud Asset Inventory and third-party tools. Palo Alto Networks advises mapping cryptographic usage and auditing priority systems.

Actions:

• Deploy automated discovery tools.
• Catalog keys, certificates, and protocols.
• Tag systems by data sensitivity and exposure.

Metrics:

• Percentage of systems inventoried.
• Number of high-risk systems identified.

2. Algorithm and Software Readiness

Once you know where cryptography lives, you need software that supports PQC algorithms. Google Cloud highlights BoringSSL, Chrome, and SDKs. Accenture recommends deploying quantum-safe patches and updating vulnerability management.

Actions:

• Assess vendor support for PQC.
• Update internal libraries and frameworks.
• Train developers on quantum-safe APIs.

Metrics:

• Percentage of software stack supporting PQC.
• Number of patches applied.

3. Crypto Agility and Orchestration

Crypto agility is the ability to switch cryptographic algorithms without major engineering effort. It is the most strategic category. Google Cloud calls it "cryptographic agility". Accenture describes a "crypto-agile orchestration layer". Palo Alto Networks enables agility through inline cipher translation and automated certificate rotation.

Actions:

• Implement abstraction layers for cryptography.
• Automate certificate lifecycle management.
• Use proxies to shield legacy systems.

Metrics:

• Time to switch algorithms (mean time to remediate).
• Percentage of systems with agile crypto.

4. Integrity and Authentication

Quantum threats also target digital signatures. Google Cloud emphasizes strengthening digital signatures to prevent forgery. Palo Alto Networks includes code-signing environments in priority systems.

Actions:

• Adopt quantum-safe signature algorithms.
• Re-sign critical code and documents.
• Monitor for signature forgery attempts.

Metrics:

• Percentage of signatures quantum-safe.
• Number of critical systems with PQC signatures.

5. Governance and Funding

Accenture stresses executive alignment and governance. Without board-level support, funding and cross-functional coordination suffer.

Actions:

• Establish a quantum security steering committee.
• Integrate PQC into existing risk management.
• Allocate budget for multi-year transition.

Metrics:

• Executive sponsorship level.
• Budget allocated vs. required.

What Is the "Performance Tax" and Why Does It Matter?

Post-quantum algorithms often have larger key sizes and different computational profiles than classical algorithms. This can introduce latency and reduce throughput. Palo Alto Networks recommends measuring this "performance tax" through high-throughput pilots.

Ignoring performance can lead to failed deployments. A pilot on a production-adjacent system helps quantify the impact and inform capacity planning. For example, a VPN concentrator might see reduced concurrent connections if PQC algorithms are enabled. Knowing this ahead of time allows teams to upgrade hardware or optimize configurations.

This is a tradeoff: stronger security may come at a performance cost. The right balance depends on the specific application and risk tolerance. Not all systems need PQC immediately; prioritizing high-value data and critical infrastructure is prudent.

Recommendations: A Step-by-Step Roadmap

Based on the synthesized evidence, we recommend the following phased approach. This roadmap balances quick wins with long-term strategic transformation.

Phase 1: Discover and Prioritize (0-6 months)

• Inventory cryptographic assets across the organization, using automated tools where possible.
• Identify high-risk systems: internet-facing applications, VPNs, TLS/mTLS, APIs, identity systems, code-signing.
• Assess current vendor PQC support and gaps.
• Secure executive sponsorship and initial funding.

Quick win: Disable obsolete protocols and algorithms (e.g., SHA-1, RSA-1024).

Phase 2: Update and Validate (6-18 months)

• Update software stacks to support PQC algorithms (e.g., BoringSSL, SDKs).
• Deploy quantum-safe patches and update vulnerability management.
• Conduct high-throughput pilots to measure performance tax.
• Validate quantum-safe APIs in test environments.

Quick win: Enable hybrid key exchange on VPNs where supported.

Phase 3: Deploy and Automate (18-36 months)

• Implement inline cipher translation for legacy systems and IoT.
• Automate certificate rotation and hybrid VPN tunnels.
• Build crypto-agile orchestration layer.
• Begin migrating high-risk systems to PQC.

Quick win: Use automated certificate management to reduce manual errors.

Phase 4: Govern and Evolve (36+ months)

• Treat post-quantum security as an ongoing discipline.
• Continuously monitor standards and update algorithms.
• Expand PQC to all systems over time.
• Report progress to board and adjust strategy.

This roadmap is not linear; phases overlap. The key is to start now.

How Does This Connect to Broader Cybersecurity Strategy?

Quantum readiness is not a standalone initiative. It intersects with threat intelligence, vulnerability management, and incident response. For a comprehensive understanding of threat vectors, see Understanding Cyber Threats and Attack Vectors: A Complete Guide. The same inventory and prioritization skills apply to ransomware preparedness; our analysis of Top Ransomware Trends and Predictions for 2025 provides complementary insights. Additionally, zero-day vulnerabilities often target cryptographic implementations; Zero-Day Vulnerabilities: How They Work and How to Defend Against Them explains how to mitigate those risks.

What Are the Limitations of Current Guidance?

Most guidance assumes a certain level of organizational maturity and resources. Smaller organizations may struggle with the complexity. One exception is the use of managed security service providers who can offer PQC readiness assessments. Also, the timeline for quantum threats is uncertain; over-investing too early could divert resources from pressing risks. A balanced approach considers the sensitivity and longevity of data. Data with a short confidentiality window (e.g., session tokens) is less urgent than data with decades-long sensitivity.

Another limitation is the lack of finalized standards. NIST has been running a post-quantum cryptography standardization process, but algorithms may still evolve. Crypto agility mitigates this risk by allowing swaps.

Conclusion: The Time to Act Is Now

Quantum computing threats are not a future problem; they require present action. The risk of "Harvest Now, Decrypt Later" means encrypted data stolen today could be compromised tomorrow. Organizations must begin by inventorying cryptographic assets, updating software, and building crypto agility. The synthesis of guidance from Google Cloud, Accenture, and Palo Alto Networks provides a clear roadmap.

Key takeaways:

• Start with a cryptographic inventory to know where you are vulnerable.
• Prioritize high-risk systems: VPNs, TLS, APIs, identity, code-signing.
• Build crypto agility to switch algorithms without disruption.
• Engage executive leadership and secure funding.
• Measure performance tax and plan accordingly.

By following these steps, information security professionals can protect their organizations against quantum computing threats and ensure long-term data confidentiality and integrity. The transition is complex, but waiting increases risk. The tools and knowledge are available; the time to start is now.