Harvest Now, Decrypt Later
Key Points
- Quantum computers exploit superposition, entanglement, and other non‑classical physics to explore many possible solutions simultaneously, giving them a huge advantage for tasks such as molecular simulation and massive data searches.
- While this breakthrough promises breakthroughs like faster drug discovery and solving problems far beyond today’s supercomputers, it also creates a new security risk: data encrypted today could be decrypted later once quantum hardware matures.
- The phrase “harvest now, decrypt later” captures this threat, warning that adversaries may collect currently protected information now and break the encryption with future quantum attacks.
- Traditional cryptographic schemes rely on mathematical problems that are infeasible for classical computers, but quantum algorithms can solve many of those problems efficiently, rendering current encryption vulnerable.
- Organizations must recognize the impending quantum risk and begin planning for quantum‑resistant cryptography to safeguard long‑term valuable data.
Sections
- Quantum Computing and Future Data Theft - The speaker explains quantum computers’ unique capabilities and warns that their eventual power could decrypt today’s encrypted data, emphasizing the “harvest now, decrypt later” risk.
- Quantum Threat to Modern Cryptography - The speaker explains how future quantum computers could instantly break current encryption, urging immediate adoption of quantum‑resistant safeguards because attackers can harvest encrypted data today and decrypt it later.
- Public vs Symmetric Encryption Basics - The speaker explains how asymmetric (public‑key) and symmetric encryption operate, their mathematical foundations, common algorithms such as RSA and AES, typical key lengths, and why their security relies on difficult mathematical puzzles.
- Quantum Threats and Post-Quantum Solutions - The speaker explains how Grover weakens symmetric keys—necessitating larger key sizes—while Shor completely breaks asymmetric cryptography, prompting a shift to lattice‑based post‑quantum algorithms.
- Achieving Crypto Agility Today - The speaker explains how to future‑proof cryptographic implementations by adopting crypto‑agility, using quantum‑safe algorithms on existing hardware, and automating a NIST‑guided cryptographic inventory to discover, manage, and remediate vulnerable assets.
- Planning Enterprise Encryption Migration - An executive outlines prioritizing, tracking, and transitioning large‑scale encryption implementations toward quantum‑safe solutions, including interim crypto proxy usage.
- Building Crypto Agility Today - The speaker stresses that although past encrypted data breaches cannot be reversed, organizations can limit future "harvest‑now‑decrypt‑later" risks by adopting crypto‑agile people, processes, and technology now.
Full Transcript
# Harvest Now, Decrypt Later **Source:** [https://www.youtube.com/watch?v=TU9CRyAOekQ](https://www.youtube.com/watch?v=TU9CRyAOekQ) **Duration:** 00:19:03 ## Summary - Quantum computers exploit superposition, entanglement, and other non‑classical physics to explore many possible solutions simultaneously, giving them a huge advantage for tasks such as molecular simulation and massive data searches. - While this breakthrough promises breakthroughs like faster drug discovery and solving problems far beyond today’s supercomputers, it also creates a new security risk: data encrypted today could be decrypted later once quantum hardware matures. - The phrase “harvest now, decrypt later” captures this threat, warning that adversaries may collect currently protected information now and break the encryption with future quantum attacks. - Traditional cryptographic schemes rely on mathematical problems that are infeasible for classical computers, but quantum algorithms can solve many of those problems efficiently, rendering current encryption vulnerable. - Organizations must recognize the impending quantum risk and begin planning for quantum‑resistant cryptography to safeguard long‑term valuable data. ## Sections - [00:00:00](https://www.youtube.com/watch?v=TU9CRyAOekQ&t=0s) **Quantum Computing and Future Data Theft** - The speaker explains quantum computers’ unique capabilities and warns that their eventual power could decrypt today’s encrypted data, emphasizing the “harvest now, decrypt later” risk. - [00:03:09](https://www.youtube.com/watch?v=TU9CRyAOekQ&t=189s) **Quantum Threat to Modern Cryptography** - The speaker explains how future quantum computers could instantly break current encryption, urging immediate adoption of quantum‑resistant safeguards because attackers can harvest encrypted data today and decrypt it later. - [00:06:13](https://www.youtube.com/watch?v=TU9CRyAOekQ&t=373s) **Public vs Symmetric Encryption Basics** - The speaker explains how asymmetric (public‑key) and symmetric encryption operate, their mathematical foundations, common algorithms such as RSA and AES, typical key lengths, and why their security relies on difficult mathematical puzzles. - [00:09:30](https://www.youtube.com/watch?v=TU9CRyAOekQ&t=570s) **Quantum Threats and Post-Quantum Solutions** - The speaker explains how Grover weakens symmetric keys—necessitating larger key sizes—while Shor completely breaks asymmetric cryptography, prompting a shift to lattice‑based post‑quantum algorithms. - [00:12:37](https://www.youtube.com/watch?v=TU9CRyAOekQ&t=757s) **Achieving Crypto Agility Today** - The speaker explains how to future‑proof cryptographic implementations by adopting crypto‑agility, using quantum‑safe algorithms on existing hardware, and automating a NIST‑guided cryptographic inventory to discover, manage, and remediate vulnerable assets. - [00:15:39](https://www.youtube.com/watch?v=TU9CRyAOekQ&t=939s) **Planning Enterprise Encryption Migration** - An executive outlines prioritizing, tracking, and transitioning large‑scale encryption implementations toward quantum‑safe solutions, including interim crypto proxy usage. - [00:18:47](https://www.youtube.com/watch?v=TU9CRyAOekQ&t=1127s) **Building Crypto Agility Today** - The speaker stresses that although past encrypted data breaches cannot be reversed, organizations can limit future "harvest‑now‑decrypt‑later" risks by adopting crypto‑agile people, processes, and technology now. ## Full Transcript
Quantum computers are coming.
These systems leverage properties of physics that define logic in the conventional sense you and I know it.
Superposition of states, particles acting like waves and entanglement, which Einstein, by the way, called spooky action at a distance,
are just a few of the counterintuitive properties of quantum systems.
Quantum computers don't follow a straight path like the computers we use today.
Instead, they explore many possible answers at once and use clever quantum tricks to zero in on the right one.
This makes them especially good at solving certain kinds of problems,
like simulating molecules or searching through massive amounts of data that would have taken even our fastest supercomputers thousands of years to figure out.
However, like any new technology, they will also introduce some new challenges.
Let's take a look at one of them.
I want you to remember four words.
If you remember nothing else out of this video, then these four, I'll consider it a success.
Here they are.
Harvest now, decrypt later.
What does that mean?
Well, it means the future is coming to steal your data.
Not in some sci-fi movie plot sort of way, but in a very realistic scenario.
It means that you can encrypt all of your sensitive data today, and in the not too distant future, it suddenly won't be secret anymore.
If those secrets are time-sensitive and won't mean much in a few months or years, then probably you don't need to worry.
But if they do have value going forward, and please listen up as we unpack what those four words mean, harvest now, decrypt later.
Okay, let's go back and give some context.
Sensitive data like an organization's intellectual property or client data,
we'll call it personally identifiable information or other secrets like that need to be protected from prying eyes.
Only those with a need to know should have access.
So we use cryptography to protect these secrets.
Plain text like this goes into a crypto algorithm,
and we use a randomly generated key to turn plain text that's readable into cipher text that is not.
And that ciphertext can then be transmitted over a public network or stored in a database without fear that an attacker will be able to read it.
Then when we need to reverse the process for an authorized user, we decrypt the cipher texts and get back to the original message.
Sounds great, and it all works.
In fact, we rely on this technology every day for all sorts of important personal and business transactions.
Crypto works though, because there are certain hard mathematical problems built into the algorithms that we use
that even the most powerful supercomputers can't solve in a thousand years.
That's why your secrets are secret.
But a disruptive new technology is on its way that threatens to upend this arrangement if we aren't careful to prepare for it.
Quantum computers are amazing.
They leverage physical properties that defy conventional logic.
They will literally save lives as we're able to use them to develop more effective drug therapies to treat diseases, and that's really just the beginning.
Put simply, they have the potential to solve in a few hours certain types of problems that would take many lifetimes to work out on today's classical computers.
Sounds great, right?
Well, one of those hard problems also just happens to be the basis for how our classical crypto works.
In other words, quantum will do great things, but it also has the potential to break all of our existing cryptography.
And that's gonna be a problem.
Suddenly the secrets aren't secret anymore.
When will it do this?
Well, nobody really knows for sure.
The consensus in the crypto community seems to be that it will probably be in the next five to 10 years, but it could happen tomorrow.
If someone discovers a novel way to use the power of today's quantum systems,
then suddenly the whole thing falls.
So don't get too comfortable because unlike Y2K this could hit us at anytime without warning,
but let's assume that doesn't happen,
then why bother with this hypothetical now?
Why not just wake you up in a few years when this becomes an actual threat?
Well because of these words i mentioned at the beginning harvest now, decrypt later.
In fact, a bad guy could right now make a copy of your encrypted data and just hold on to it.
Can't read it, but maybe he sees this as it goes across a network.
Maybe he sees an encrypted database that you have that's a backup and makes a copy of that.
All he has to do is hold on to that and then wait for the future to come to him,
because in the future you'll be able to use a quantum computer, feed this information in and be able to read the data, get back to the plain text that he was actually looking for.
Another way of looking at it is to imagine if you had a time machine and you could travel into the future and bring back with you a super powerful quantum system.
Now you would be able break all the encrypted messages at will.
What would be the impact of such a scenario?
Well, as I mentioned before, sensitive information like intellectual property, PII, things like that.
Even national secrets would be revealed.
Digital signatures could be forged, electronic records would no longer become reliable,
payment systems would be broken, the security of critical infrastructure like the power grid would be impacted.
A lot of bad stuff would happen to put it mildly.
Let's take a brief look at the cryptography that underlies this problem in the first place.
First of all, how do we use crypto today?
Well, there are mainly two types of algorithms that we use.
And we use them in combination all the time.
They're symmetric algorithms and asymmetric algorithms.
And a symmetric algorithm uses a single key.
That key we're going to use to encrypt and decrypt.
The key that you use to encrypt can only be the key that will decrypt if the cryptosystem is working properly.
An asymmetric system, however, has two keys.
It has asymmetry.
Whatever you can encrypt with one key, can only be decrypted with the other key.
So that's the way this works.
We often refer to it as public key cryptography or PKI.
That's the ways it works.
There's some mathematical relationships between those two keys, more detailed than we want to get into here, that make that work.
And it looks like magic, but it's not.
So it's all based on math.
And the most common version of a symmetric algorithm we use these days is the advanced encryption standard.
Most common of the asymmetric algorithms,
RSA from the first initial of the last names of the guys that created it.
So these things are out there crypto key length sizes for asymmetric for AES in particular range usually most people use 128 today 256 is also possible.
That's the bit length and the longer the key the stronger the crypto is the harder it is for someone to guess.
The asymmetric algorithms because of the nature of the way they have to have longer keys.
So they're in the range of 1024 or 2048 bit long.
So that's what we're using today,
and to give you an example, this stuff only works because there's a hard math problem that is difficult to solve.
If those problems became easy to solve, then the crypto goes away.
So think of it as a puzzle.
If you want to get an answer to the question, you have to be able to solve the puzzle.
What's the puzzle?
Well, let's take an example of the asymmetric stuff.
The RSA algorithm in particular, relies on the fact that prime factorization is a hard math problem.
Now what do I mean by that?
You remember that a prime number is a number that can only be divisible evenly by itself and one, so you can't divide it evenly by anything else.
So let's start with a number like twenty one.
And I ask you, tell me what are the two prime factors of twenty one?
In other words, what two prime numbers will be multiplied together to equal 21.
You say, well Jeff, it's not really very hard.
It's seven and three.
Seven can't be divided by anything else, but seven in itself, seven and one, so therefore it's a prime number, the same thing for three.
So there, you've done a prime factorization of the number 21.
Congratulations, that was an easy problem to solve.
However, try to do the same with this number.
Now, you're gonna need the rest of your natural life and many others in order to do it.
In fact, if you want to know, it turns out it's these two numbers, just if you're interested.
But that's a really hard math problem.
Even our classical computers are not able to solve that very easily.
So what are we going to do instead?
Well, we've got to do something different in order to make this thing work.
So what we do, in fact, what we found is with a quantum computer, that particular factorization problem actually isn't very hard to do.
A quantum system can try lots of different possibilities and get to the answer much, much quicker than we normally would.
So if we take, for instance, a key that's a symmetric key, let's say it's basically, maybe we start with 128 bits.
Well, there's a thing called Grover's algorithm.
And Grover will basically make this half as strong.
It will essentially knock out half of the strength of that key.
Well, that's with using a quantum computer of sufficient strength.
Now, again, today's classical computers can't do that, but a quantum system will be able to.
So what do we do to compensate for that?
Well, actually, it's actually pretty easy.
We just double the size of the key.
We go and start using 256-bit keys, and now we've gotten back to the level of strength that we're used to.
So problem sort of solved.
We just have to go back and re-encrypt everything with stronger keys.
However, this is a different situation when we move over here to the asymmetric.
And these keys are longer.
There's a thing called Shor's algorithm, and Shor's makes mincemeat of the whole thing.
Shor's doesn't just make these kinds of things half as strong, it makes them really not strong at all.
So in fact, we need something entirely different because Shor's breaks these asymmetric algorithms, and we depend on them for key distribution,
and if you can't distribute keys, you can do any of this kind of stuff.
So, what we need are new algorithms,
and those new algorithms, in fact, exist.
And they're based on what's known as lattice cryptography.
So beyond the scope of this, but you can take a look and learn more about lattices and how they come to the rescue.
The good news is that we have a solution now to this future problem.
In fact, a lot of people have been working on this space for a decade already.
In 2024, that work culminated in the U.S. National Institute of Standards and Technology, also known as NIST,
coming out with four finalist algorithms, and these four are designed to be quantum safe cryptography, or also known, as post-quantum cryptography.
And the experts believe that these will be resistant to cracking by future quantum computers.
While IBM has been working hard to bring the benefits of quantum computing to the world,
we're also working hard to mitigate the risks to crypto as three of those four finalist algorithms actually had IBM contributors working on them.
And we hired a person who worked on the fourth.
So we have people who understand this space
and we've also contributed these algorithms to the open source community so that everyone can benefit from these and use these to make our system safe.
But that's not the end of the story.
In order for there to be a happy ending.
You have to actually implement these new standards in your systems.
That's not going to be easy since some organizations have literally thousands of applications that leverage cryptography that will need to be updated.
In order to do this, you're gonna need people, process and technology all working together to transform to this post-quantum era.
And because of the harvest now decrypt later situation I mentioned before, you need to actually start on this, well, yesterday.
So remember that time machine that I mentioned?
That's gonna come in handy because all you have to do is build one of those, go back in time, re-encrypt all your data with these new algorithms and you're set.
Well, okay, until the time machine technology is perfected, here's what you actually can do now.
The goal here is this thing we call crypto agility.
In other words, I want to future proof my cryptographic implementations so that if we have to make changes again in the future,
I don't have a brittle system that I have to go back and do all this pain again with that I could just snap something else in and continue going.
And we're gonna need some tools in order to get there.
Oh, and the great thing here that I need to underscore is that you don't need a quantum computer to use quantum cryptography.
All the tools and algorithms that will make you quantum safe run on today's classical computers.
So we'll take that technology and what we then need to do is apply these steps,
discover,
manage,
and remediate.
So let's start with the discovery part of this.
And NIST gives us some guidance.
They have said organizations should create a cryptographic inventory that offers visibility into how the organization leverages cryptography.
That sounds like sound advice to me.
So what that means is if I'm going to create that inventory I need a way to find it,
and if you try to do it manually I guarantee you'll miss some.
So what you want to do is have a system that has some automated scanning capability
where it goes and looks across your source code, it looks across the network,
and it looks for all implementations of cryptography in your environment.
There was one major bank that when they did this type of exercise, they found that they had more than 4,000 applications with cryptography built into them.
That's a lot.
Stop and think for just a second.
If they did a conversion, a migration, of every one of those.
Let's say they could do one a day.
That actually would be pretty aggressive.
If they did one a today, how long is it gonna take them to get to full blown crypto agility and crypto safe, quantum safe?
The number is more than 10 years.
So this is why, again, the problem is a now problem that we have to start working on.
We can't wait for the future on this,
and then once you've done that, another thing you wanna take a look at is If I know where all of this stuff is, I wanna find out where the vulnerable crypto is.
Probably it's most of it today, but I'm gonna create that list and catalog what kinds of algorithms are being used in each one of these cases,
and then ultimately the goal is to create this thing, a CBOMB, a cryptographic bill of materials.
That's where we're gonna have this whole list that we've now discovered,
and now with that, we can move into the next step.
The next step involves managing all of these.
And with the management, I'm gonna start with policy.
So I need to spell out as an organization, in other words, define what is our crypto policy.
What levels of strength do we need?
What kinds of things need to be encrypted?
What kinds things need be done?
That sort of thing.
And I wanna be able to do some enforcement of whatever that policy is.
Ultimately, this is a massive project.
Again, if we're talking 4,000 implementations and yours might be smaller, but it's still gonna be a large project, I need to also figure out what are the priorities.
I need prioritize each one of these, and then once I've picked out, because since I can't do all of them at once,
pick the ones that are the most impactful, that have the most sensitive information in them, and then go after those.
Then I need track the results of all of this.
This is a massive multi-year project.
I need to see where I am in fact on this journey because it is in fact going to be a journey.
Then we start moving into the remediation phase.
This is where we're gonna start moving from our classical crypto into the quantum safe crypto or the post-quantum crypto PQC.
That's the stuff that we ultimately are trying to get to.
Well, if I can't convert all of these things in an instant, I can just snap my fingers and make it happen.
What could I do in order to get there?
Well, one thing that would give some level of protection today would be to use a proxy, a crypto proxy that sits in and does some of this conversion for me.
Now here's how it would work.
Let's say we have a user who out here is on a browser and their browser, let's say it's already been updated to be crypto safe.
It's using one of these new algorithms,
but our backend legacy app over here as not.
In fact, we might be afraid to even crack this thing open
because we don't know how many lines of code are in there and they were written a million years ago and all that kind of thing,
but we can't afford, this has got keys to the kingdom, we can afford just to have it vulnerable.
So what I could do is stand up a proxy in the middle.
This proxy would be communicating, it understands the quantum safe crypto algorithms.
So it's doing quantum safe crypto between the browser and the proxy
and then the proxy continues with the normal classical algorithms back to the back end application.
So that way we at least encrypt if this is the part that's over the public network, we atleast have strengthened that part without having to make changes to the backend.
And this part all maintains within our very private network where the risk is lower.
So that's an important capability that allows us to move at least while we're in migration phase and be able to tolerate and work with these new algorithms.
Another thing that we're going to want to do is test the performance.
So these algorithms we believe are going to be highly performant, but it all depends on the individual implementation that you're using.
And if you have a poor implementation, well you might end up in a mess.
So what we need to be able to do is make sure we have something that works well.
And you want to be a test and make sure that those things work.
You can't go back in time to prevent past cases of harvesting of your encrypted data, but you can start now on the path to crypto agility.
With the right people, process, and technology, you can mitigate the risk of harvest now decrypt later, at least until you build that time machine.