<blockquote>
<p>Is it the same thing just with different names [...]?</p>
</blockquote>
<p>Yes.</p>
<p>This became known as &quot;anti-klepto&quot; initially (full disclosure: I suggested this name). Later, a decision at Blockstream was made to refer to the project as &quot;anti-exfil&quot;, for the simple reason that the word &quot;<a href="https://en.wikipedia.org/wiki/Kleptography" rel="nofollow noreferrer">kleptography</a>&quot; is a very rare term that probably only cryptography experts have heard of (as opposed to &quot;exfiltration&quot;, which is understandable to a wider audience).</p>

CC BY-SA 4.0
2022-08-01T15:52:59.417Z
2022-08-01T15:52:59.417Z
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<p>What is the difference between the <a href="https://shiftcrypto.ch/blog/anti-klepto-explained-protection-against-leaking-private-keys/" rel="nofollow noreferrer">anti-klepto</a> protocol (also <a href="https://github.com/ElementsProject/secp256k1-zkp/blob/ed69ea79b429beae4260917e08fe60317d38ee8d/include/secp256k1_ecdsa_s2c.h#L100-L155" rel="nofollow noreferrer">here</a>) and <a href="https://medium.com/blockstream/anti-exfil-stopping-key-exfiltration-589f02facc2e" rel="nofollow noreferrer">Anti-Exfil</a>? Is it the same thing just with different names or are there differences? It seems they are both addressing the nonce covert channel attack?</p>

<security><cryptography><terminology><hardware-wallet>
What's the difference between the anti klepto protocol and anti exfil?
Michael Folkson
# What's the difference between the anti klepto protocol and anti exfil?

(Asked by: username_0 on 2022-08-01)

What is the difference between the [anti-klepto](https://shiftcrypto.ch/blog/anti-klepto-explained-protection-against-leaking-private-keys/) protocol (also [here](https://github.com/ElementsProject/secp256k1-zkp/blob/ed69ea79b429beae4260917e08fe60317d38ee8d/include/secp256k1_ecdsa_s2c.h#L100-L155)) and [Anti-Exfil](https://medium.com/blockstream/anti-exfil-stopping-key-exfiltration-589f02facc2e)? Is it the same thing just with different names or are there differences? It seems they are both addressing the nonce covert channel attack?

**Tags:** security, cryptography, terminology, hardware-wallet


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## 1 answers

### Answer by username_1 on 2022-08-01. Score: 3 | Accepted answer

> Is it the same thing just with different names [...]?

Yes.

This became known as "anti-klepto" initially (full disclosure: I suggested this name). Later, a decision at Blockstream was made to refer to the project as "anti-exfil", for the simple reason that the word "[kleptography](https://en.wikipedia.org/wiki/Kleptography)" is a very rare term that probably only cryptography experts have heard of (as opposed to "exfiltration", which is understandable to a wider audience).


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