As laboratories around the world race to build out a cryptographically relevant quantum computer, we at Cloudflare are racing towards a 2029 target deadline for full post-quantum readiness. While we’ve already transitioned many of our products to post-quantum encryption, we still have work to do to support post-quantum authentication and achieve full post-quantum readiness across our platform.

We’re taking a maximalist stance (“PQ everything!”), because as an infrastructure provider to the world, we want to give our customers the peace of mind that using Cloudflare ensures that their traffic is future-proofed against quantum adversaries.

But how does one accomplish such a massive migration at an organization of our size and scale? After all, cryptography is the base layer for almost all of the world’s digital systems, including the software services and the networking protocols that power our platform.

To drive our PQ migration, we have three key goals.

First, we want to help our product and engineering teams understand how cryptography is being used and how they should be upgrading it. This should cover both the upgrades to post-quantum encryption and to post-quantum authentication. Many of our products have already been upgraded to post-quantum encryption over TLS 1.3, but we still want to cover the long tail of TLS connections, as well as upgrade any other uses of public-key encryption. Meanwhile, it’s still early days for our deployment of post-quantum authentication.

Next, we want to provide progress metrics for the migration. These might include per-repository and per-product counts of the use of classical and post-quantum cryptography.

Finally, we want to surface prerequisites early. If our products or platform rely on protocols that don’t yet have a PQ migration plan (because PQ variants of the system have not yet been considered, because PQ standards do not exist or lack consensus, or because software libraries or other key ecosystem components do not yet have PQ support), then we need to know now. That way we can work with the relevant stakeholders, standards bodies and ecosystems to help drive their PQ migration plans, so that we can meet our own 2029 PQ migration timeline.

This post is the story of how we’re going about this. We explain how we turned to AI to help us solve some of our problems and how we’re developing an internal tool called CryptoLabe to help us. CryptoLabe is named after the mariner’s astrolabe, a navigation instrument refined by Portuguese navigators. Just as an astrolabe helped sailors determine where they were and chart a course, CryptoLabe helps us discover cryptography in our code, understand how it is used, and chart a path to post-quantum migration.

CryptoLabe is highly specialized to our internal systems (our repositories, our ticketing systems, and internal documentation processes) and still evolving as we continue its development, so we aren’t making it available to customers. Nevertheless, we are sharing our learnings so that other organizations can build upon our efforts as they work through their own PQ migration journey.

The scale of the problem

The software that powers most Cloudflare products lives inside our single centralized source control management platform. This means we can find most uses of cryptography across our platform by just looking through our codebase.

While the centralization of our codebase is a marked advantage for us, we still need to contend with three challenges that come with the scale of this problem. First, our code is spread across many repositories. Second, cryptography rarely announces itself plainly in the code. Instead, it hides in

• shared libraries that a repository imports but may or may not actually call
• upstream and protocol defaults, like a TLS 1.3 listener that is configured to negotiate a classical key exchange such as X25519 rather than post-quantum X25519MLKEM768
• configuration files that select algorithms far away from the code that uses them, like a TLS responder whose key exchange protocols are pinned in a YAML file stored in a different repository
• code paths that are dead, test-only, or on a path to being deprecated

Third, cryptography discovery is about more than just pattern matching. Grepping for certain algorithm names (e.g. “RSA” or “X25519”) overcounts, because it finds cryptography in unused code. Grepping also undercounts, because it misses defaults and indirect uses in dependencies and configuration. Most importantly, it can't tell you how the cryptography is used. A classical ECDSA signature could be part of a JWT, IPsec, TLS, or SSH, and each has a completely different migration path. Many uses also depend on the other side of the connection: a TLS server may support both post-quantum key exchange and classical key exchange; the one it chooses to use would depend on the client.

Turning to AI

It turns out that AI is pretty good at doing more than just grepping. A model can search a codebase, follow evidence across files, and return structured analysis. It can also enrich findings by pulling information from other sources, like our internal documentation and ticketing systems. In fact, AI can even explain how cryptography is being used and how it should be updated. We’ve been putting that idea to the test as we develop CryptoLabe.

As we said before, our first two goals are to (1) discover and understand the use of cryptography in our codebase, and also (2) to get metrics on the state of our PQ migration. Towards these goals, our current implementation of CryptoLabe performs scans in two stages, as shown in the figure below.

The first “discovery” stage starts by mapping the repository. It then searches for cryptography through source, configuration, manifests, lockfiles, scripts, tests, and documentation. Among other things, the scan looks for the use of cryptography like key agreement, signatures, asymmetric encryption, PKI, tokens, credentials, hardware security module integrations, and more. This discovery stage produces a set of "raw observations."

Each raw observation feeds a run of the second stage. This “analysis” stage first re-checks the observation against the source code. It then investigates how the cryptographic operation is used at runtime, what role the repository plays, and which internal or external parties it depends on. When necessary, it can inspect related code in other repositories to complete the analysis. Finally, it takes a pass over its own conclusions, searching for missing or conflicting evidence such as configuration overrides, test-only code, or incorrect assumptions about runtime behavior.

Next, the model assigns a classification to the finding. If there is not enough evidence to assign a classification, the model assigns More evidence needed, External dependency, or Unknown rather than guessing.

This is the current list of classifications used by CryptoLabe, containing catch-all classifiers which will likely be refined as we proceed through our migration. (As an example, we could refine our classifiers by splitting the “encryption” classifier into key agreement and HPKE; you get the idea.)

Finally, it generates a report that serves two audiences: (1) product managers who need to understand what the migration means for their product, and (2) engineers that need enough detail to execute the migration.  

Here’s a (cropped) view of one of our reports:

While we’ve been iteratively reviewing findings against the source code and with relevant engineers, we do not yet have a ground-truth dataset for reproducibly comparing different versions of the prompts we’ve tried for CryptoLabe.

Built on Cloudflare’s Developer Platform

We built CryptoLabe on Cloudflare's Developer Platform. Here’s the architecture:

CryptoLabe runs across two Cloudflare Workers. There’s a scanner Worker that runs the scans. And there’s an inventory Worker that serves the dashboard, exposes the API, and stores everything in a D1 database. The two communicate through Service Bindings. A scan starts when someone requests it from the dashboard, and the inventory Worker passes the request to the scanner.

Orchestrating a scan

We need a way to keep a scan alive and on track from start to finish, without building our own job orchestration system. We did this with Agents SDK. Each repository gets its own persistent coordinator built on a Durable Object (DO). A bounded queue in front of the coordinators limits how many scans run at once. When a scan's turn comes, the coordinator tracks its progress and handles cancellation, retries, and recovery.

The coordinator doesn't do the analysis itself. It hands the work to Cloudflare Workflows, so that they can persist progress and automatically retry failed steps. The coordinator moves each repository through four stages:

1. discovery Workflow (the first scanning stage that produces raw observations)
2. deep analysis Workflow (the second stage, run on each raw observation)
3. merge Workflow (that builds a list of findings for a given repository, including combining repeated or similar finds)
4. publish workflow (that hands results back to the inventory Worker)

The first two workflows need the model to have access to the repository's code. We want this access to be isolated, so we don’t risk damaging the codebase. That’s why CryptoLabe downloads the repository once, at an exact commit, at the start of each scan, and then stores that snapshot in R2. Each Workflow then restores the snapshot into a fresh, short-lived Cloudflare Sandbox, an isolated container. The model then works with the Sandbox through a small set of read-only tools on an immutable snapshot of the code, even if the codebase changes while the scan is still running.

Calling the model at scale

If we want to scan through all of our (many!) repositories, we have to worry about both cost and capacity.

For cost, the model loop sends its requests through AI Gateway to cost-effective open-weight models hosted on Workers AI. Putting the model behind AI Gateway also makes it easy to switch models as better or cheaper ones become available.  

Capacity became a problem once we scanned many repositories at once. Bursts of model requests began triggering HTTP 429 (rate limit) responses from AI Gateway, and scans retrying independently only made the bursts worse. We solved this with a single, global Durable Object that paces every model request across all scans, including retries. When any scan hits a rate limit, the cooldown is shared and all scans back off together, so concurrent scans share the available capacity instead of competing for it.

Prerequisites and hard cases

Let’s now get into our third goal: surfacing prerequisites and hard cases early.

A lot of ink has been spilled about ecosystem readiness for the PQ migration, and we are now going to spill some more. As everyone knows, a PQ migration cannot happen in a vacuum. For migration to succeed, post-quantum cryptography must be supported in relevant software libraries (e.g. BoringSSL) and across parties that participate in the ecosystem (e.g. clients, browsers, origins, cloud proxies, certificate authorities, etc.). Standards are also an important indicator of ecosystem support, although a standard that is still in “draft” state does not necessarily mean deployment cannot proceed. As an example, we deployed X25519MLKEM768 in TLS 1.3 back in 2022 when it was still a “draft” at the Internet Engineering Task Force (IETF) while it was only finalized as RFC 10024 in 2026.

Either way, our point is that in order to upgrade a system to PQ cryptography, we need to understand its dependencies and level of ecosystem support. 

That’s why CryptoLabe uses the concept of “prerequisites” to highlight findings that cannot be immediately remediated by an individual product team working alone.

A prerequisite can be something as straightforward as “we are currently blocked on migrating to post-quantum JWTs.” We say this is straightforward because there is already a standard (RFC 9964) for post-quantum JWTs. Nevertheless, if our software libraries don’t yet support validating post-quantum JWTs, or if we’re using a token issuer that does not yet issue post-quantum JWTs, we can’t go company-wide and ask each of our product teams to start PQ-ing their JWTs. This migration is blocked until we solve its core prerequisites. CryptoLabe lets us group together findings that (likely) have the same prerequisite, which also helps us decide how to prioritize resolving these prerequisites.

For example, the snapshot below shows the six findings from CryptoLabe that have post-quantum SAML as a prerequisite. (SAML is a protocol for single sign-on (SSO).)

On the other hand, there may be uses of cryptography that lack even a basic level of ecosystem support. We’ve been calling these “hard cases.” To find them, we wrote a separate prompt that ignores “vanilla” uses of cryptography (e.g. ordinary TLS between internal systems) and instead looks for custom cryptographic protocols, keys, or signatures used in size-constrained fields, cryptography built into hardware, specialized cryptographic constructions (like blind signatures), protocols without a PQ standard, and dependencies on external parties that do not yet support PQ cryptography.

This prompt is shorter and simpler than those used for CryptoLabe, since its only job is to find hard cases.  In our qualitative review, we found that it got better results when it ran in one fell swoop against all our repositories, while also taking in context from our internal ticketing and documentation system.  

Here’s an example of a “hard case” we found: a certificate carried in an HTTP header. Post-quantum certificates and signatures are larger than their classical counterparts, so if the header (or an intermediary, or the application processing the header) assumes a certificate has a certain size, changing the signature algorithm may break the system. Our next step is to determine whether this code will remain in use in the long term. If it will, we need to measure the relevant size limits and decide how to accommodate the larger certificate.

An important lesson here is that no single scan finds everything. Our repository-by-repository scans were effective at discovering common uses of cryptography. Meanwhile, this targeted scan worked better for “hard cases” because it ignored well-understood cryptography and had more context about each product and its dependencies.

The bottom line is that different approaches find different things, and every finding still needs to be checked by the engineers who understand how the system actually works.

Sharing our prompts

We’ve been messing around with the best way to write prompts for CryptoLabe for the last several months.  We don’t yet have a ground-truth dataset for comparing one prompt’s performance against another, and we are not convinced we have 100% coverage of all uses of cryptography in our codebase. Instead, we have iterated by running scans, reviewing findings with the engineers that maintain the repositories, investigating misses that came up during these reviews and revising the prompts.   Nevertheless, we decided to publish selected prompts, so other teams can learn from and adapt our approach. These prompts are starting points, not a standalone version of CryptoLabe, and the quality of their results will depend on the model, tools, context, and engineering review available.

Thinking through your own PQ migration

At Cloudflare, we’re taking a maximalist approach to our PQ migration because of our goal of acting as a provider of post-quantum cryptography for customers and the Internet at large. But most organizations do not need to start by finding every use of cryptography in every repository in every one of their products. In fact, most organizations should not be doing this, because at this time it's a waste of precious resources.

Before scanning a single repository, you can protect traffic in bulk wherever possible. If your websites run through Cloudflare, we protect your data in transit with post-quantum encryption already today; check this out with our new PQ visibility features. Our SASE platform, Cloudflare One, provides post-quantum encryption for private network traffic. Post-quantum encryption is provided at no additional cost and without requiring you to upgrade every origin server or private application on your enterprise network. This gives you a compensating control while you work through discovering and understanding the use of cryptography inside your own systems.

An exhaustive cryptographic inventory is not a prerequisite for action. Instead, organizations should first identify the systems whose compromise would matter most, discover their use of cryptography, and then PQ that cryptography in priority order. Here is one way to begin:

1. Choose a repository for one important system. Start with something that handles sensitive or long-lived data, authenticates users or software, or is exposed to the public Internet.
2. Run cryptography discovery against that repository. We hope our description of CryptoLabe will be helpful to this effort!
3. Validate the results. Ask the team who owns the system to validate the results of cryptography discovery and confirm that the cryptography finding is needed long term and needs to be upgraded to PQ. It’s important to remember that it might not need to be immediately upgraded to PQ if there is another compensating control in place.
4. Prioritize action. Figure out what upgrades you can make now and what upgrades are blocked. Record shared prerequisites that need help from a library, vendor, standards group, or another part of your organization. Prioritize your findings and make a plan for addressing the highest-impact systems and prerequisites first.

That gives you the beginning of a PQ transition plan, without requiring a complete map of every cryptographic operation in your organization. CryptoLabe is still ever-evolving, but its scans and results have been illuminating to us as we plan our migration. We hope these shared learnings will be useful as you continue to work through your own PQ migration.

Acknowledgements: Many people across Cloudflare provided feedback on and contributed to CryptoLabe, including Davide Marquês, Peter Wu, Phil Schmieder, JP Aumasson, Andrew Galloni, Christopher Patton, Luke Valenta, Mari Galicer, Vânia Gonçalves, and the Client, Tunnel and Gateway teams who reviewed reports produced by the tool.

Today, we are introducing additional post-quantum (PQ) cryptography visibility tools into Cloudflare's Application Security and Logs products. You can now inspect and graph the adoption of post-quantum TLS 1.3 encryption for live traffic from directly within Logpush, Log Explorer, and the HTTP Traffic Analytics dashboard. By surfacing the key exchange algorithm negotiated on every incoming request from visitors to our platform, Cloudflare gives customers granular, per-connection telemetry to audit their post-quantum posture, assess compliance, and identify cryptographic gaps across their domains.

Cloudflare is targeting 2029 for full post-quantum security, and executing a cryptographic transition at scale requires detailed telemetry. We’ve already deployed post-quantum encryption across many of our products, including in our cloud-proxy platform and on every on-ramp and off-ramp of our SASE platform.   As many of our customers work towards quantum-readiness deadlines around 2030, we’re helping ease the transition by making post-quantum encryption the default in many of our products, sharing learnings from our internal cryptography discovery tool, and launching the new post-quantum visibility features for TLS that we’ll cover in this blog.

Bringing post-quantum visibility to the domain level

When it comes to post-quantum visibility, we already have macro-level visibility into Internet-wide post-quantum adoption in TLS through Cloudflare Radar. On Radar, we track global post-quantum encryption statistics, both when Cloudflare proxies HTTP requests from visitors (the visitor-to-Cloudflare connection) and when Cloudflare connects to origin servers (the Cloudflare-to-origin connections), as shown in this figure.

From Radar we can see that about 70% of browser-generated traffic hitting Cloudflare's network (on the visitor-to-Cloudflare connection) is protected with post-quantum encryption using hybrid ML-KEM (FIPS 203).  Meanwhile, we can see that today, just about 15% of origins that Cloudflare connects to use hybrid ML-KEM. These are aggregate numbers; the first number is aggregated across all the browser-generated traffic we see, and the second number is aggregated across all the origins we connect to.

We’ve also recently launched Automatic Key Exchange for the Cloudflare-to-origin connection, which reveals which cryptographic algorithms are supported by a given origin. This is useful because outdated configurations can cause an origin to connect to Cloudflare using classical cryptography, even if it does support a post-quantum encryption. 

While Radar and Automatic Key Exchange both provide valuable macro-level views of Internet-wide readiness, our customers have asked us to be able to go beyond aggregate numbers and dive into the behavior of individual domains.

We have long provided visibility into the TLS version used at individual domains (TLS 1.3, TLS 1.2, etc.).

But until now we have not exposed information about the cryptographic algorithms used with the TLS version used at the domain level. This means customers could not answer questions like “What fraction of traffic to my domain www.example.com is using post-quantum encryption?” This information is helpful when aiming to comply with regulatory frameworks, troubleshooting a migration to post-quantum encryption, or seeking to understand which fraction of traffic that is exposed to future quantum adversaries. Now, these questions can be answered.

Post-quantum cryptography in TLS

Before we get into the new product features, let’s do a quick review of post-quantum cryptography in TLS, so we can understand the information that the feature surfaces.

In 2024, the National Institute of Standards and Technology (NIST) stated that RSA and Elliptic Curve Cryptography (ECC) should be deprecated by 2030, and many governments and regulators have since gotten behind that deadline. That’s why today, many of our products are protected with post-quantum encryption using a cryptographic key agreement algorithm called hybrid ML-KEM. Post-quantum encryption is needed right now to stop harvest-now-decrypt-later attacks, where an adversary harvests data today and then decrypts it in the future once powerful quantum computers come online. Organizations that have data that are valuable even if decrypted in 3–10 years (public sector, defense, finance, telecom, healthcare, and others), should consider immediately protecting their traffic with post-quantum encryption.  

 In TLS 1.3, the key exchange group X25519MLKEM768 is the only recommended algorithm for post-quantum encryption. It is now the algorithm preferred by most major browsers. (Note: post-quantum encryption is not available in TLS 1.2 or any earlier version of TLS.)   If you are using Chrome, you can check the key agreement algorithm used by this webpage (or any other) by right-clicking “Inspect”, going to the “Security” tab and looking for the below:

With X25519MLKEM768 in TLS 1.3, the client and server execute both:

• the Elliptic Curve Diffie-Hellman Key Exchange (ECDHE) over curve X25519 and
• the post-quantum Module Lattice Key Encapsulation Mechanism (ML-KEM)

X25519 and MLKEM768 each produce a shared secret. TLS then combines those two secrets and uses the result to encrypt TLS traffic. This hybrid approach provides belt-and-suspenders security; as long as one of the two key exchanges is secure, the resulting shared secret is also secure. TLS 1.3 also supports other key exchange groups, including X25519, P-256 and P-384, all of which are just classical ECDHE over different elliptic curves; these algorithms are still used all over the web. In earlier versions of TLS you can also find key agreement based on the RSA algorithm, which is quantum-vulnerable and thankfully much less popular these days due to many known classical security problems.

But post-quantum encryption is only the first part of the story; the second part is post-quantum authentication. Once powerful quantum computers exist, we need to worry about upgrading the certificates and signatures used in TLS 1.3 away from RSA and ECC and towards post-quantum algorithms like ML-DSA. We’re actively making progress towards that goal. In fact, we recently announced that origins can use ML-DSA-44 certificates over TLS 1.3 to connect to Cloudflare, and today we announced that we’re launching a certificate authority that will support post-quantum Merkle Tree Certificates. Nevertheless, for now it remains true that post-quantum encryption with hybrid MLKEM is more broadly deployed than post-quantum authentication.

Bringing post-quantum visibility to the visitor-to-Cloudflare connection

Today we’re making it possible to see the extent to which post-quantum key agreement is used on the visitor-to-Cloudflare connection for any domain in HTTP Traffic Analytics dashboard, Logpush, and Log Explorer.

To view the TLS key exchange data on your domains, go to the Cloudflare Dashboard, and navigate to HTTP Traffic under the Analytics tab. Here you’ll get in-depth statistics about the kinds of traffic visiting your domains, now including a dedicated card for TLS Key Exchange groups on the visitor-to-Cloudflare connection. (Scroll down to find it!) Here’s a look at a TLS Key Exchange card for one of our test domains:

As you can see, the majority of the traffic to this domain uses post-quantum X25519MLKEM768 (in TLS 1.3).  We see some traffic using classical ECDHE over curve X25519 or P-256 (in TLS 1.3 or below).  The traffic labeled “None” is using either RSA key agreement (in TLS 1.2 or below) or no TLS at all. And finally we have a small number of visitors using the now-deprecated X25519Kyber768Draft00 algorithm with TLS 1.3, which we implemented back before X25519MLKEM768 was fully standardized by the Internet Engineering Task Force (IETF). We’ve waited to remove support for X25519Kyber768Draft00 until observed connections are diminishingly small, to avoid regressing clients for which this is their only way to support PQ encryption.

While we’re here, we’ll just drop a few tips about PQ-ing your traffic. If you look at your domain and find no use of X25519MLKEM768 at all, you should confirm that TLS 1.3 is enabled. In the Cloudflare dashboard, select your domain, go to SSL/TLS > Edge Certificates, and then scroll until you find the TLS 1.3 switch; switch TLS 1.3 to On. (There is no separate post-quantum setting: when TLS 1.3 is enabled and a visitor supports X25519MLKEM768, Cloudflare negotiates it automatically.) Also, if the vast majority of your traffic is over classical X25519, P-256, P-384, or None, it might be because most visitors to that domain are non-browser clients that lack support for X25519MLKEM768 and/or TLS 1.3. (Again, most major browsers do prefer to negotiate a TLS 1.3 connection with X25519MLKEM768.)

The key exchange group can now also be a filtering term in the HTTP Traffic dash. Here’s how to take a look at the traffic that is not using post-quantum encryption with X25519MLKEM768:

Analytics are great for aggregate investigations, but being able to see this information in individual log lines can be even more powerful. You can enable the new ClientTLSKeyExchangeGroup field, under the TLS category in the HTTP Requests dataset, to gain visibility into individual post-quantum key exchange in your Log Explorer and Logpush connection logs.

With this new field enabled, you’ll see it start appearing in your Logpush HTTP Request logs, like so:

{
  "EdgeResponseStatus":200,
  "EdgeStartTimestamp":"2026-09-20T00:08:24Z",
  "RayID":"...",
  "ClientTLSKeyExchangeGroup":"X25519MLKEM768"
}

Visibility to origins and more

The release of the key exchange group stats represents the first major milestone in our broader cryptographic visibility initiative. Designed for scalability, our underlying telemetry pipeline is built to ingest additional cryptographic parameters from TLS handshakes.

That’s why we’ve also surfaced the key exchange group from the Cloudflare-to-origin connection and to provide end-to-end visibility from eyeball to origin in Logpush as OriginTLSKeyExchangeGroup. (This group will be the same for all visitor connections made to that domain, which is why it's not shown in the HTTP Traffic Analytics dashboard).

And for customers that use legacy origin servers that are unlikely to support modern post-quantum cryptography, don’t despair. You can put the origin server behind a Cloudflare Tunnel, to tunnel traffic from the origin server to Cloudflare over TLS 1.3 with X25519MLKEM768, without need to upgrade the legacy origin server itself. This is what the network configuration would look like if you put your origin server behind a Cloudflare Tunnel:

Eventually we’ll be able to also surface post-quantum authentication (namely the algorithm used for certificates and signatures in TLS, including Merkle Tree Certificates) once we start to see a broader-based deployment of that technology.

Your domain has started its post-quantum journey

If your domain is behind Cloudflare, its post-quantum journey is already underway. Check HTTP Traffic Analytics dash and your logs to see the percentage of visitor connections to your domain that already use TLS 1.3 with post-quantum encryption (X25519MLKEM768).  You can also check logs to see if you’re using post-quantum encryption on the Cloudflare-to-origin connection. If your origin server is too ossified to support post-quantum cryptography, then just put it behind Cloudflare Tunnel. With the right settings and visibility, you can protect more of your traffic on Cloudflare from harvest-now-decrypt-later attacks today.

We thank Luke Valenta, Ollie Hsieh and Alex Krivit for contributions to this work.

On June 22, 2026, President Trump signed Executive Order 14412, "Securing the Nation Against Advanced Cryptographic Attacks." The order sets a December 31, 2030, deadline for federal agencies to transition their most sensitive systems to post-quantum encryption, and a December 31, 2031, deadline for post-quantum authentication. The EO also directs federal contractors to comply with post-quantum Federal Information Processing Standards (FIPS) by the end of 2030.

We welcome this executive order. The U.S. government has a long track record of using federal leadership and procurement to drive adoption of new technologies across the broader industry. We've seen this work with IPv6, with routing security and the Resource Public Key Infrastructure (RPKI), and with DNSSEC, and we’re glad to see this tradition continue with post-quantum cryptography.

The EO is especially important at this moment because the timeline for Q-Day, the day that quantum computers can break the public-key cryptography used across the Internet, has been accelerated. In April 2026, Cloudflare moved our own target for full post-quantum security to 2029, following research breakthroughs from Google and Oratomic. This EO updates guidance from 2024, when the National Institute of Standards and Technology (NIST) stated that the classical public key cryptography used across the Internet (namely RSA and Elliptic Curve Cryptography, which can be broken once powerful quantum computers become available) should be deprecated by 2030 and disallowed by 2035. 

The Internet’s transition to post-quantum encryption is well underway, while the transition to post-quantum authentication has only just begun. Today, over two-thirds of browser traffic to Cloudflare's network is protected with post-quantum encryption, and most of our products support post-quantum key agreement. Our SASE platform, Cloudflare One, provides post-quantum encryption across all major on-ramps and off-ramps, including TLS, MASQUE, and IPsec. We've recently started deploying post-quantum authentication and aim to be fully post-quantum secure by 2029. The EO is an excellent foundation and builds on work from the previous two Administrations. We've been doing the work the EO is asking federal agencies to do since 2019, we have some thoughts on what the order gets right, we see opportunities for the Office of Management and Budget (OMB) to strengthen and facilitate cost-effective agency migration, and we provide a roadmap for how organizations and agencies can advance their transition most effectively.

The EO’s requirements for federal systems

The bulk of the EO's binding requirements are aimed at two categories of federal systems: High Value Assets (HVAs) and high impact systems. HVAs are federal information or systems designated by OMB as the government's crown jewels: systems whose compromise would significantly affect national security, foreign relations, or public confidence. These include databases that hold millions of federal employee records, systems that process classified intelligence, or platforms that manage federal financial transactions. Meanwhile, high impact systems are those where confidentiality, integrity, or availability is rated "high" under FIPS 199, meaning a breach could cause severe harm including loss of life, major financial damage, or significant degradation of an agency's ability to carry out its mission.

The EO has the power to bind federal agencies, but not other organizations (i.e., critical infrastructure, state, local, tribal and territorial governments, academia, civil society). That’s why the EO only gives these deadlines to federal agencies:

National Security Systems are explicitly excluded from these deadlines. They are on a separate, classified track managed by the NSA with deadlines between 2030 and 2033 already set in 2022.

Two migrations: encryption and authentication. Both should begin now.

The EO splits the PQC migration into two phases: post-quantum key establishment (encryption) by 2030, and post-quantum digital signatures and certificates (authentication) by 2031. This accurately reflects the availability of post-quantum encryption across the Internet today. Our own deadline for full post-quantum readiness (including authentication) is 2029, but we are amongst the earliest adopters in the industry. 

We are also happy to see the EO focusing on NIST-standardized post-quantum cryptographic algorithms and not Quantum Key Distribution (QKD), since QKD does not operate at Internet scale due to its need for specialized hardware and dedicated physical links between sender and receiver.  

Now let’s have a deeper look at the two migrations called for and required in the EO: post-quantum encryption and post-quantum authentication.

Post-quantum encryption is needed today to stop harvest-now-decrypt-later attacks, where an adversary collects encrypted traffic today and decrypts it later once quantum computers are powerful enough. Post-quantum encryption is especially valuable for organizations handling data that will still have value to adversaries 3-10 years from now, like government agencies, banks, healthcare organizations, defense contractors, and telecom providers.

Post-quantum authentication stops an adversary that has a quantum computer from forging certificates to impersonate servers, generating malicious code signatures, or gaining unauthorized access to systems.  Post-quantum authentication is needed only after Q-Day risk materializes, because it stops attacks that are possible only once a cryptographically-relevant quantum computer (CRQC) exists.

It’s important to put the migration timelines in context with advancements in quantum computing. In addition to yesterday’s EO on post-quantum security, President Trump also signed an EO to accelerate deployment and commercialization of quantum computing, sensing, and networking. The fact that the EO sets a 2031 deadline for post-quantum authentication tells us something important: the U.S. government believes there is a non-negligible chance that a CRQC could be operational around that time. 

Road to Quantum Safety

What about the state of these two technologies? The migration to post-quantum authentication is a bigger challenge than post-quantum encryption for a few reasons, including:

• Post-quantum ML-DSA digital signatures are larger than classic digital signatures, which could have an impact on performance of some systems, for instance in short-lived TLS connections. That’s why we are working with Google Chrome on Merkle Tree Certificates to solve the performance problem for TLS. 
• The dependency chain for post-quantum authentication is longer, requiring coordinated upgrades across clients, servers, certificate authorities, certificate transparency logs, root stores, and browsers. 
• There is only limited ecosystem deployment of post-quantum authentication so far, as compared to the much broader deployment of post-quantum encryption.

It is interesting that the EO sets a one-year gap between the encryption and authentication deadlines. One extra year of calendar time is tight, so this work cannot proceed sequentially. The ecosystem needs to start working on both of these targets concurrently, or we will miss this 2031 deadline. 

Cryptographic deployment across the Internet cannot happen without standards developed by the Internet Engineering Task Force (IETF). They are working to transition their protocols to post-quantum cryptography.  The TLS community is ahead, with the IETF PLANTS working group making good progress on post-quantum certificates for TLS. There is much work to do here, and we look forward to supporting the IETF in its efforts. 

Supply chain pressure that helps everyone

The EO includes requirements for federal contractors, which may turn out to be the most impactful part of the EO. 

Namely, the FAR Council must publish proposed rules requiring "covered contractors" to comply with NIST FIPS incorporating PQC algorithms by December 31, 2030 (Sec. 6(c)). The FAR Council must also publish proposed rules requiring contractors to implement vulnerability disclosure programs that cover cryptographic vulnerabilities (Sec. 6(d)). These proposed rules need to go through notice-and-comment rulemaking, but the EO has a December 31, 2030, target which is still important. This deadline is one year earlier than federal agencies are required to complete their post-quantum authentication migration, so that federal contractors will be ready before agencies hit their own deadlines.

Federal agencies can only migrate to PQC if the products they buy support PQC. To put this into practice, CISA released its Product Categories for Technologies That Use Post-Quantum Cryptography Standards, drawing a clear line between technologies where PQC is already "widely available" versus those still "transitioning." The "widely available" list includes cloud platforms (IaaS, PaaS), web browsers and servers, chat and messaging software, and endpoint security products like full disk encryption. For these categories, CISA's guidance is clear: organizations should procure only PQC-capable products. The "transitioning" list, where PQC is not yet widely available, includes networking hardware (routers, firewalls, switches), identity and access management systems (HSMs, certificate authorities, identity providers), email servers and clients, and database systems.

By telling contractors their products must be PQC-compliant by 2030, and directing agencies to immediately favor PQC-capable vendors in mature markets, the federal framework forces the vendor ecosystem to ship PQC-capable products on a fixed timeline. Products that vendors build to federal requirements will end up used by hospitals, banks, universities, and small businesses, which makes PQC support more broadly available. Cloudflare is among the many vendors subject to these requirements, and because networking software and cloud services are already designated by CISA as widely available PQC categories, we've already shipped post-quantum encryption across most of our products at no extra cost. 

Critical infrastructure and PQ for everyone

The EO also speaks to critical infrastructure: energy, financial services, water, transportation, telecommunications, healthcare, and other systems whose failure would have a serious or significant impact on the country. While the EO has no hard migration deadline for critical infrastructure owners and operators, the EO directs certain federal agencies to "assist" critical infrastructure owners and operators with their PQC migration plans (Sec. 5(a)).

While the EO focuses mostly on federal agencies and critical infrastructure in the U.S., post-quantum cryptography is important to every Internet-connected individual and organization. Harvest-now-decrypt-later attacks are a risk today. And after Q-Day, the risk of unauthorized access by an adversary armed with a quantum computer will impact any organization, big or small. When we launched free universal SSL in 2014, our CEO Matthew Prince wrote:

Having cutting-edge encryption may not seem important to a small blog, but it is critical to advancing the encrypted-by-default future of the Internet. Every byte, however seemingly mundane, that flows encrypted across the Internet makes it more difficult for those who wish to intercept, throttle, or censor the web.

We feel the same way about post-quantum cryptography. That’s why every post-quantum upgrade we build is available to all customers, on every plan, at no additional cost.

Opportunities for OMB’s implementation guidance

The EO sets the direction, and now OMB has 90 days to provide important clarifications and operational guidance to achieve the most effective PQC migration across federal agencies (Sec. 4(b)). Based on what we've learned from our own PQC migration, here are a few elements that we suggest that guidance should include:

Define what it means to “transition.” The EO requires agencies to "transition" their systems to PQC, but it never defines what "transition" means. Does it mean the system supports PQC algorithms? That it prefers them? Or that classical cryptography has been disabled entirely?

These are very different security postures. A system that supports ML-KEM but still allows a classical-only TLS handshake is vulnerable to downgrade attacks. An adversary capable of intercepting traffic could force the connection back to classical key exchange. The system would have "transitioned" to PQC in name, but still be vulnerable to the same quantum attacks the order is trying to prevent.

History is instructive. When SSLv3 was deprecated after the POODLE attack in 2014, servers kept SSLv3 enabled for backwards compatibility, allowing attackers to force connections to downgrade and then exploit SSLv3's weaknesses. It took years for the ecosystem to actually turn SSLv3 off. To avoid repeating this pattern, we need a clear definition of “done” that includes disabling quantum-vulnerable cryptography to prevent downgrades.

Crypto agility: Crypto agility is the ability to swap cryptographic algorithms without re-architecting your systems. The EO mandates migrating to specific NIST crypto standards, but says nothing about building systems that can swap cryptographic algorithms if these algorithms need to change in the future. Crypto agility doesn't mean supporting every algorithm at once. It means building systems so that when the community converges on a better algorithm in the future, the upgrade is a configuration change, not a re-architecture. The OMB should include this in its guidance.

CBOM or quantum impact inventory? The EO directs CISA and NIST to publish guidance on the minimum elements for a cryptographic bill of materials (CBOM) within 270 days (Sec. 5(d)). A CBOM is an inventory of the cryptographic algorithms, protocols, and implementations used in a given hardware or software product, similar to a software bill of materials (SBOM).

In theory, CBOMs are a good idea. In practice, we'd caution against treating exhaustive cryptographic inventories as a prerequisite for action. A detailed CBOM of every algorithm in every library in every product takes a long time to produce, it can take federal agencies an entire procurement cycle of discovery tooling and consulting, and it potentially becomes stale by the time the inventory is complete. Also, a CBOM doesn’t list systems that should be using cryptography but are not. And a CBOM lists keys without an understanding of their purpose, making them less useful for organizations trying to understand the risk associated with a quantum-vulnerable key.

We think that a quantum impact inventory is a more productive framing. What would be the impact if the system or its data is compromised? How likely is that to happen? What measures can be taken to mitigate the risk, whether a drop-in replacement, a software update, or a compensating control like tunneling traffic over bulk post-quantum connection or isolating it from the Internet? How feasible is each option and what dependency chain does it create? Identifying these informs where to take action first. You can fill in the details of a full CBOM over time if that makes sense for your organization, but you should start by discovering your most exposed and impactful systems.

Making post-quantum cryptography affordable to all. True national resilience fails if post-quantum cryptography is treated as a gated luxury rather than a universal baseline. OMB policy must resist vendor lock-in or toll booths that leave underfunded critical infrastructure behind or increase technical debt at federal agencies. 

What to do now: don't wait for 2030

You do not have to wait for 2030 or an exhaustive cryptographic inventory to start your migration. History has shown that updating cryptography is hard and can take a long time; other organizations should start sorting out their migrations as well. So as we wait for OMB guidance for federal agencies, here’s what we recommend for all organizations:

Protect your Internet traffic now. Start with traffic that crosses the public Internet, because that is the easiest for adversaries to harvest now and the most immediately at risk. If your web traffic flows through Cloudflare, your connections are largely protected with post-quantum encryption. If your enterprise network uses Cloudflare One, your private network traffic is also protected. If your provider doesn't support post-quantum encryption, switch to one that does. Even if the individual applications running inside your network haven't been upgraded yet, start tunneling your traffic through post-quantum encrypted infrastructure to protect it in bulk, even if individual systems are not yet inventoried and upgraded.

Update procurement. Make "post-quantum encryption by default, at no additional cost, with a clear roadmap for post-quantum authentication and crypto agility" a requirement in every technology procurement. If your vendor charges extra for post-quantum security or doesn't have a roadmap or plan, ask why or find another vendor.

Quantum impact inventory. For traffic that stays inside your private network perimeter and is not exposed to the public Internet, the harvest-now-decrypt-later risk is lower because an adversary would need to be on your network to capture it. But you still need to know what cryptography your internal systems use, so you can plan your migration. Use a quantum impact inventory as a tool to prioritize your efforts, for example focusing on systems or connections that handle sensitive data or are exposed on the public Internet. 

Plan for authentication now. The 2031 deadline for post-quantum authentication will come faster than you think. Start identifying your long-lived keys, root certificates, and code-signing infrastructure. These are the highest-priority targets for a quantum attacker, and they have the longest dependency chains to upgrade. Now is a great time to update your software libraries and automate certificate provisioning even if post-quantum certificates are not yet available in your ecosystem. And make sure your vendors are planning to be ready for the looming post-quantum authentication deadline.

Aligning policy and international standards

At the same time, work should also start now on aligning global government policy with international standards. We were glad to see that Section 5(b) directs the State Department to engage foreign governments and industry groups to encourage adoption of NIST-standardized PQC algorithms. 

Here’s why this matters. Cryptography migrations cannot be run in a vacuum, with each country operating within its own borders. A TLS connection between a U.S. person and a server abroad only works if both ends negotiate the same cryptography. NIST has been running open international cryptographic competitions for decades. The AES competition (1997-2001) produced the encryption standard used across the Internet today, selecting a cipher designed by Belgian cryptographers. The SHA-3 competition (2007-2012) produced the latest hash standard, selecting an algorithm designed by a Belgian-Italian team. The PQC competition (2016-2024) followed the same open model: anyone could submit, anyone could analyze, and the winning algorithms were designed by international teams. ML-KEM, the key agreement standard now being deployed across the Internet, was created largely by European cryptographers. These are open, internationally vetted algorithms. NIST organized the competitions, but the results belong to the global cryptographic community. 

The risk ahead is fragmentation. If different jurisdictions mandate different algorithms, the result is cipher bloat and increased attack surface: more code to write, test, and audit, more surface for downgrade attacks, and slower deployment for everyone. We've seen this happen firsthand in IPsec, where the lack of an interoperable standard led vendors to ship proprietary PQ key agreement algorithms that couldn’t interoperate, delaying the migration by years. The TLS community went the opposite way, converging on a single hybrid key agreement (X25519MLKEM768), and deployment followed quickly.

We are big fans of NIST, and especially its leadership in vetting standards globally and standardizing cryptography worldwide. We encourage the Trump Administration to work with Congress to ensure that NIST has appropriate resources, staffing, and tooling to meet current and emerging deliverables in this EO and others, like America's AI Action Plan.

We'd like to see State Department-led engagement drive real alignment: adoption of the same NIST algorithms across allied nations, alignment on timelines, and mutual recognition of cryptographic algorithms and modules. The Internet is one network, and its cryptography should be one standard.

Speeding up CMVP

As a final note, the EO directs NIST to revise the processes used by the Cryptographic Module Validation Program (CMVP) to accelerate validations of cryptographic modules (Sec. 6(b)). Having bumped up against the CMVP program for years, we are extremely happy to see this in the order.

CMVP exists for a good reason. Federal agencies and their contractors need a way to verify that the cryptography inside a product actually does what it claims: that AES is implemented correctly, or that random number generators have enough entropy. CMVP has been tuned for a steady state where cryptography doesn’t change much.

Going forward, CMVP needs to be adjusted to accept the realities of the impending migration. We welcome the FedRAMP update stream that allows updated modules to be used immediately before final validation. This allows faster adoption of post-quantum cryptography, and correction of implementation errors that were missed in validation. Similar allowances for CMVP are essential.

Go forth and PQ all the things

This post-quantum EO is a meaningful step. It sets real deadlines and creates supply chain pressure that will accelerate adoption across the industry. 

For organizations starting their own migration, we suggest you start by protecting your public Internet traffic along with updates to your procurement requirements, followed by a quantum impact inventory to figure out where to focus next. Do not let cryptography inventory slow you down from deploying post-quantum encryption across your most sensitive systems immediately. 

Cryptographic deployment across the Internet depends on standards developed by the IETF. The TLS community is further along, but there is lots more work to do across other protocol communities, and we look forward to supporting those efforts.

Let us go forth and PQ all the things, quickly and together. Free TLS helped encrypt the web. Free post-quantum cryptography will help secure it for what comes next.

You can get started now on Cloudflare by visiting our PQC page.

Watch

While more than two-thirds of human-generated TLS traffic to Cloudflare is already protected by post-quantum cryptography, the world of site-to-site networking has been a different story. For years, the IPsec community remained caught between the high bar of Internet-scale interoperability and the niche requirements of specialized hardware. That gap is now closing. 

Earlier this month, we announced that Cloudflare has moved its target for full post-quantum security forward to 2029, spurred by several recent advances in quantum computing. To advance that goal, we’ve made post-quantum encryption in Cloudflare IPsec generally available.

Using the new IETF draft for hybrid ML-KEM (FIPS 203), we’ve successfully tested interoperability with branch connectors from Fortinet and Cisco — meaning you can start protecting your wide-area network (WAN) against harvest-now-decrypt-later attacks today using hardware you already have.

This post explains how we implemented the new hybrid IPsec handshake, why it took four years longer to land than its TLS counterpart, and how the industry is finally consolidating around a standard that works at Internet scale.

Cloudflare IPsec

Cloudflare IPsec is a WAN Network-as-a-Service that replaces legacy network architectures by connecting data centers, branch offices, and cloud VPCs to Cloudflare's global IP Anycast network. Customers get simplified configuration, high availability (if a data center becomes unavailable, traffic is automatically rerouted to the nearest healthy one), and the scale of Cloudflare's global network. This is done through encrypted IPsec tunnels that support both site-to-site WAN, outbound Internet connections, and connectivity to the Cloudflare One SASE platform. 

Post-quantum encryption in IPsec

Cloudflare IPsec now uses post-quantum encryption with hybrid ML-KEM (FIPS 203) to stop harvest-now-decrypt-later attacks. These are attacks where an adversary harvests data today and then decrypts later, after Q-Day, when there are powerful quantum computers that can break the classical public key cryptography used across the Internet.  Harvest-now-decrypt-later attacks are becoming a concern for more organizations as Q-Day approaches faster than expected.

ML-KEM (Module-Lattice-Based Key-Encapsulation Mechanism) is a post-quantum cryptography algorithm that is based on mathematical assumptions that are not known to be vulnerable to attacks by quantum computers. It does not require special hardware or a dedicated physical link between sender and receiver. ML-KEM is intentionally designed to be implemented in software across standard processors to provide post-quantum encryption of network traffic. 

Draft-ietf-ipsecme-ikev2-mlkem specifies post-quantum encryption for IPsec using hybrid ML-KEM, which combines the well-understood security of classical Diffie-Hellman and the post-quantum security of ML-KEM in a single, standards-compliant handshake. Specifically, a classical Diffie-Hellman exchange runs first, its derived key encrypts a second exchange that runs ML-KEM, and the outputs of both are mixed into the session keys that secure IPsec data plane traffic sent using the Encapsulating Security Payload (ESP) protocol. 

Our interoperable implementation 

Earlier we announced the closed beta of our implementation of draft-ietf-ipsecme-ikev2-mlkem in production in our Cloudflare IPsec product and tested it against a reference implementation (strongswan). Now that we have made this implementation generally available, we have also confirmed interoperability with several other vendors, including Cisco and Fortinet, which is a big win for this new standard.

Cisco: Customers using Cisco 8000 Series Secure Routers after version 26.1.1 as their branch connector can also now establish post-quantum Cloudflare IPsec tunnels per draft-ietf-ipsecme-ikev2-mlkem.

Fortinet: Customers using Fortinet FortiOS 7.6.6 and later as their branch connector can now establish post-quantum Cloudflare IPsec tunnels to Cloudflare's global network per draft-ietf-ipsecme-ikev2-mlkem.

The importance of being interoperable

Given that upgrading cryptography is hard and can take years, our 2029 target date for a full update to post-quantum cryptography is going to require concentrated effort. That’s why we hope the IPsec community continues to focus on the development of interoperable standards like draft-ietf-ipsecme-ikev2-mlkem.

Let us explain why these standards are vitally important. A full specification for hybrid ML-KEM in IPsec, draft-ietf-ipsecme-ikev2-mlkem, became available only in late 2025. That's roughly four years after support for hybrid ML-KEM landed in TLS. (In fact, Cloudflare turned on hybrid post-quantum key agreement with TLS in 2022, even before NIST finalized the standardization of ML-KEM, because the TLS community quickly converged on a single, interoperable approach and pushed it into production. Today more than two-thirds of the human-generated TLS traffic to Cloudflare's network is protected with hybrid ML-KEM.)

The four-year delay is likely due in part to the IPsec community's continued interest in Quantum Key Distribution (QKD), as codified in RFC 8784, published in 2020. We've written before about why QKD is not part of our post-quantum strategy: QKD requires specialized hardware and a dedicated physical link between the two parties, which fundamentally means it will not operate at Internet scale. Also, QKD does not provide authentication, so you still need post-quantum cryptography anyway to stop active attackers. It’s difficult to find implementations of QKD that interoperate across vendors.   

The U.S. NSA, Germany's BSI, and the UK's NCSC have all warned against solely relying on QKD. Post-quantum cryptography, by contrast, runs on the hardware you already have, authenticates the parties at both ends, and works end-to-end across the Internet. 

RFC 9370, published in 2023, opened the door to post-quantum cryptography in IPsec, allowing up to seven key exchanges to be run in parallel with classical Diffie-Hellman. However, RFC 9370 did not specify which ciphersuites should be used in these parallel key exchanges. In the absence of that specification, some vendors shipped early implementations under RFC 9370 before the hybrid ML-KEM draft was available, defining their own ciphersuites including some which are not NIST-standardized. This is exactly the kind of “ciphersuite bloat” NIST SP 800 52r2 warned against. And the risks to interoperability have played out in practice: Cloudflare IPsec does not yet interoperate with Palo Alto Networks' RFC 9370–based implementation, because it was launched before draft-ietf-ipsecme-ikev2-mlkem was available. 

Fortunately, we now have draft-ietf-ipsecme-ikev2-mlkem that fills in the gaps in RFC 9370, specifying hybrid ML-KEM as one of the key exchange mechanisms that can be operated in parallel with classical Diffie-Hellman. We hope to add Palo Alto Networks to the list of interoperable post-quantum branch connectors as the industry continues to consolidate around draft-ietf-ipsecme-ikev2-mlkem.

But the journey towards interoperable post-quantum IPsec standards is not over yet. While draft-ietf-ipsecme-ikev2-mlkem supports post-quantum encryption, we still need IPsec standards for post-quantum authentication, so that we can stop attacks by quantum adversaries on live systems after Q-Day. Given the shortened timeline for full post-quantum readiness, we hope the IPsec community will continue to focus on interoperable PQC implementations, rather than diverting focus to niche use cases with QKD.

Towards an interoperable post-quantum Internet

At Cloudflare, we’re helping make a secure and post-quantum Internet accessible to everyone, without specialized hardware and at no extra cost to our customers. Post-quantum Cloudflare IPsec is one more step on our path to full post-quantum security by 2029, and we’re doing it in a way that ensures that the Internet remains open and interoperable for years to come. 

We at Cloudflare have aggressively adopted Model Context Protocol (MCP) as a core part of our AI strategy. This shift has moved well beyond our engineering organization, with employees across product, sales, marketing, and finance teams now using agentic workflows to drive efficiency in their daily tasks. But the adoption of agentic workflow with MCP is not without its security risks. These range from authorization sprawl, prompt injection, and supply chain risks. To secure this broad company-wide adoption, we have integrated a suite of security controls from both our Cloudflare One (SASE) platform and our Cloudflare Developer platform, allowing us to govern AI usage with MCP without slowing down our workforce. 

In this blog we’ll walk through our own best practices for securing MCP workflows, by putting different parts of our platform together to create a unified security architecture for the era of autonomous AI. We’ll also share two new concepts that support enterprise MCP deployments:

• We are launching Code Mode with MCP server portals, to drastically reduce token costs associated with MCP usage; 
• We describe how to use Cloudflare Gateway for Shadow MCP detection, to discover use of unauthorized remote MCP servers.

We also talk about how our organization approached deploying MCP, and how we built out our MCP security architecture using Cloudflare products including remote MCP servers, Cloudflare Access, MCP server portals and AI Gateway. 

Remote MCP servers provide better visibility and control

MCP is an open standard that enables developers to build a two-way connection between AI applications and the data sources they need to access. In this architecture, the MCP client is the integration point with the LLM or other AI agent, and the MCP server sits between the MCP client and the corporate resources.

The separation between MCP clients and MCP servers allows agents to autonomously pursue goals and take actions while maintaining a clear boundary between the AI (integrated at the MCP client) and the credentials and APIs of the corporate resource (integrated at the MCP server). 

Our workforce at Cloudflare is constantly using MCP servers to access information in various internal resources, including our project management platform, our internal wiki, documentation and code management platforms, and more. 

Very early on, we realized that locally-hosted MCP servers were a security liability. Local MCP server deployments may rely on unvetted software sources and versions, which increases the risk of supply chain attacks or tool injection attacks. They prevent IT and security administrators from administrating these servers, leaving it up to individual employees and developers to choose which MCP servers they want to run and how they want to keep them up to date. This is a losing game.

Instead, we have a centralized team at Cloudflare that manages our MCP server deployment across the enterprise. This team built a shared MCP platform inside our monorepo that provides governed infrastructure out of the box. When an employee wants to expose an internal resource via MCP, they first get approval from our AI governance team, and then they copy a template, write their tool definitions, and deploy, all the while inheriting default-deny write controls with audit logging, auto-generated CI/CD pipelines, and secrets management for free. This means standing up a new governed MCP server is minutes of scaffolding. The governance is baked into the platform itself, which is what allowed adoption to spread so quickly. 

Our CI/CD pipeline deploys them as remote MCP servers on custom domains on Cloudflare’s developer platform. This gives us visibility into which MCPs servers are being used by our employees, while maintaining control over software sources. As an added bonus, every remote MCP server on the Cloudflare developer platform is automatically deployed across our global network of data centers, so MCP servers can be accessed by our employees with low latency, regardless of where they might be in the world.

Cloudflare Access provides authentication

Some of our MCP servers sit in front of public resources, like our Cloudflare documentation MCP server or Cloudflare Radar MCP server, and thus we want them to be accessible to anyone. But many of the MCP servers used by our workforce are sitting in front of our private corporate resources. These MCP servers require user authentication to ensure that they are off limits to everyone but authorized Cloudflare employees. To achieve this, our monorepo template for MCP servers integrates Cloudflare Access as the OAuth provider. Cloudflare Access secures login flows and issues access tokens to resources, while acting as an identity aggregator that verifies end user single-sign on (SSO), multifactor authentication (MFA), and a variety of contextual attributes such as IP addresses, location, or device certificates. 

MCP server portals centralize discovery and governance

^{MCP server portals unify governance and control for all AI activity.}

As the number of our remote MCP servers grew, we hit a new wall: discovery. We wanted to make it easy for every employee (especially those that are new to MCP) to find and work with all the MCP servers that are available to them. Our MCP server portals product provided a convenient solution. The employee simply connects their MCP client to the MCP server portal, and the portal immediately reveals every internal and third-party MCP servers they are authorized to use. 

Beyond this, our MCP server portals provide centralized logging, consistent policy enforcement and data loss prevention (DLP guardrails). Our administrators can see who logged into what MCP portal and create DLP rules that prevent certain data, like personally identifiable data (PII), from being shared with certain MCP servers.

We can also create policies that control who has access to the portal itself, and what tools from each MCP server should be exposed. For example, we could set up one MCP server portal that is only accessible to employees that are part of our finance group that exposes just the read-only tools for the MCP server in front of our internal code repository. Meanwhile, a different MCP server portal, accessible only to employees on their corporate laptops that are in our engineering team, could expose more powerful read/write tools to our code repository MCP server.

An overview of our MCP server portal architecture is shown above. The portal supports both remote MCP servers hosted on Cloudflare, and third-party MCP servers hosted anywhere else. What makes this architecture uniquely performant is that all these security and networking components run on the same physical machine within our global network. When an employee's request moves through the MCP server portal, a Cloudflare-hosted remote MCP server, and Cloudflare Access, their traffic never needs to leave the same physical machine. 

Code Mode with MCP server portals reduces costs

After months of high-volume MCP deployments, we’ve paid out our fair share of tokens. We’ve also started to think most people are doing MCP wrong.

The standard approach to MCP requires defining a separate tool for every API operation that is exposed via an MCP server. But this static and exhaustive approach quickly exhausts an agent’s context window, especially for large platforms with thousands of endpoints.

We previously wrote about how we used server-side Code Mode to power Cloudflare’s MCP server, allowing us to expose the thousands of end-points in Cloudflare API while reducing token use by 99.9%. The Cloudflare MCP server exposes just two tools: a search tool lets the model write JavaScript to explore what’s available, and an execute tool lets it write JavaScript to call the tools it finds. The model discovers what it needs on demand, rather than receiving everything upfront.

We like this pattern so much, we had to make it available for everyone. So we have now launched the ability to use the “Code Mode” pattern with MCP server portals. Now you can front all of your MCP servers with a centralized portal that performs audit controls and progressive tool disclosure, in order to reduce token costs.

Here is how it works. Instead of exposing every tool definition to a client, all of your underlying MCP servers collapse into just two MCP portal tools: portal_codemode_search and portal_codemode_execute. The search tool gives the model access to a codemode.tools() function that returns all the tool definitions from every connected upstream MCP server. The model then writes JavaScript to filter and explore these definitions, finding exactly the tools it needs without every schema being loaded into context. The execute tool provides a codemode proxy object where each upstream tool is available as a callable function. The model writes JavaScript that calls these tools directly, chaining multiple operations, filtering results, and handling errors in code. All of this runs in a sandboxed environment on the MCP server portal powered by Dynamic Workers. 

Here is an example of an agent that needs to find a Jira ticket and update it with information from Google Drive. It first searches for the right tools:

The model now knows the exact tool names and parameters it needs, without the full schemas of tools ever entering its context. It then writes a single execute call to chain the operations together:

This is just two tool calls. The first discovers what's available, the second does the work. Without Code Mode, this same workflow would have required the model to receive the full schemas of every tool from both MCP servers upfront, and then make three separate tool invocations.

Let’s put the savings in perspective: when our internal MCP server portal is connected to just four of our internal MCP servers, it exposes 52 tools that consume approximately 9,400 tokens of context just for their definitions. With Code Mode enabled, those 52 tools collapse into 2 portal tools consuming roughly 600 tokens, a 94% reduction. And critically, this cost stays fixed. As we connect more MCP servers to the portal, the token cost of Code Mode doesn’t grow.

Code Mode can be activated on an MCP server portal by adding a query parameter to the URL. Instead of connecting to your portal over its usual URL (e.g. https://myportal.example.com/mcp), you attach ?codemode=search_and_execute to the URL (e.g. https://myportal.example.com/mcp?codemode=search_and_execute).

AI Gateway provides extensibility and cost controls

We aren’t done yet. We plug AI Gateway into our architecture by positioning it on the connection between the MCP client and the LLM. This allows us to quickly switch between various LLM providers (to prevent vendor lock-in) and to enforce cost controls (by limiting the number of tokens each employee can burn through). The full architecture is shown below.

Cloudflare Gateway discovers and blocks shadow MCP

Now that we’ve provided governed access to authorized MCP servers, let’s look into dealing with unauthorized MCP servers. We can perform shadow MCP discovery using Cloudflare Gateway. Cloudflare Gateway is our comprehensive secure web gateway that provides enterprise security teams with visibility and control over their employees’ Internet traffic.

We can use the Cloudflare Gateway API to perform a multi-layer scan to find remote MCP servers that are not being accessed via an MCP server portal. This is possible using a variety of existing Gateway and Data Loss Prevention (DLP) selectors, including:

• Using the Gateway httpHost selector to scan for 
  • known MCP server hostnames using (like mcp.stripe.com)
  • mcp.* subdomains using wildcard hostname patterns 
• Using the Gateway httpRequestURI selector to scan for MCP-specific URL paths like /mcp and /mcp/sse 
• Using DLP-based body inspection to find MCP traffic, even if that traffic uses URI that do not contain the telltale mentions of mcp or sse. Specifically, we use the fact that MCP uses JSON-RPC over HTTP, which means every request contains a "method" field with values like "tools/call", "prompts/get", or "initialize." Here are some regex rules that can be used to detect MCP traffic in the HTTP body:

The Gateway API supports additional automation. For example, one can use the custom DLP profile we defined above to block traffic, or redirect it, or just to log and inspect MCP payloads. Put this together, and Gateway can be used to provide comprehensive detection of unauthorized remote MCP servers accessed via an enterprise network. 

For more information on how to build this out, see this tutorial. 

Public-facing MCP Servers are protected with AI Security for Apps

So far, we’ve been focused on protecting our workforce’s access to our internal MCP servers. But, like many other organizations, we also have public-facing MCP servers that our customers can use to agentically administer and operate Cloudflare products. These MCP servers are hosted on Cloudflare’s developer platform. (You can find a list of individual MCPs for specific products here, or refer back to our new approach for providing more efficient access to the entire Cloudflare API using Code Mode.)

We believe that every organization should publish official, first-party MCP servers for their products. The alternative is that your customers source unvetted servers from public repositories where packages may contain dangerous trust assumptions, undisclosed data collection, and any range of unsanctioned behaviors. By publishing your own MCP servers, you control the code, update cadence, and security posture of the tools your customers use.

Since every remote MCP server is an HTTP endpoint, we can put it behind the Cloudflare Web Application Firewall (WAF). Customers can enable the AI Security for Apps feature within the WAF to automatically inspect inbound MCP traffic for prompt injection attempts, sensitive data leakage, and topic classification. Public facing MCPs are protected just as any other web API.  

The future of MCP in the enterprise

We hope our experience, products, and reference architectures will be useful to other organizations as they continue along their own journey towards broad enterprise-wide adoption of MCP.

We’ve secured our own MCP workflows by: 

• Offering our developers a templated framework for building and deploying remote MCP servers on our developer platform using Cloudflare Access for authentication
• Ensuring secure, identity-based access to authorized MCP servers by connecting our entire workforce to MCP server portals
• Controlling costs using AI Gateway to mediate access to the LLMs powering our workforce’s MCP clients, and using Code Mode in MCP server portals to reduce token consumption and context bloat
• Discovering shadow MCP usage by Cloudflare Gateway 

For organizations advancing on their own enterprise MCP journeys, we recommend starting by putting your existing remote and third-party MCP servers behind  Cloudflare MCP server portals and enabling Code Mode to start benefitting for cheaper, safer and simpler enterprise deployments of MCP.  

_{Acknowledgements:  This reference architecture and blog represents this work of many people across many different roles and business units at Cloudflare. This is just a partial list of contributors: Ann Ming Samborski,  Kate Reznykova, Mike Nomitch, James Royal, Liam Reese, Yumna Moazzam, Simon Thorpe, Rian van der Merwe, Rajesh Bhatia, Ayush Thakur, Gonzalo Chavarri, Maddy Onyehara, and Haley Campbell.}