# Making defensive technology offensive: How to get cypherpunk ideals to the masses | Devcon SEA

- Channel: [Devcon](https://streameth.org/devcon)
- Date: 2025-10-07
- Duration: 05:53
- Watch: https://streameth.org/watch/yt-W5bRYUO-Wk8
- YouTube: https://www.youtube.com/watch?v=W5bRYUO-Wk8

## Description

Cryptography is an inherently defensive tool; it hides your information from adversaries. This is crucial to prevent censorship or monitoring of your data. But it's often sold to consumers with fearmongering about all-powerful malicious actors, which is often ignored by all except the privacy-conscious. We explore real-life examples of offensive cryptographic affordances like interoperability, efficiency, and user consent as stronger motivations for the masses to migrate to cypherpunk tech.

Speaker(s): Vivek Bhupatiraju
Skill level: Beginner
Track: Cypherpunk & Privacy
Keywords: Frameworks, Values, Use cases of cryptography, messaging

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Devcon is the Ethereum conference for developers, researchers, thinkers, and makers. 
Devcon SEA was held in Bangkok, Thailand on Nov 12 - Nov 15, 2024.
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## Transcript

[Music] cool hi guys um so my talk is going to be about basically like focused on cryptography as a defensive technology that's my area of expertise um how we can take uh various cryptographic tools that are super powerful and try to find ways to communicate them uh offensively and maybe yeah just just to be clear this is more like encryption signatur Zs this sort of thing obviously Under the Umbrella of like diac and defensive Technologies there's lots of other stuff going on and I think how I would personally Define cryptography is that it's the art of making things hard to break uh in this definition it is like very inherently defensive technology you're literally trying to make tools that is very difficult for adversaries to forge or break into or otherwise uh sort of damage the Integrity of and I want to look at just a very small set of examples here this is not comprehensive at all but uh at one really prominent use case of privacy preserving Technologies in the wild which is VPN um and bbn's I think if any of you guys have been to like New York or Chicago or a couple other major American cities you might have seen these like like mad VPN ads everywhere uh for context I personally use moad um so this is not really a dig at them but a lot of their ads are very sort of like intense Cipher Punk kind of vibe of like you know like a bit of both like hopeful but also kind of like fearmonger and I I honestly am not sure how successful this has been for them I definitely know for myself like I got mulad before these ads came on and like when I do see him in in in like the subway in the train I'm like I always think like is this like do people want to see this sort of thing and like one reference point my in my mind that I have is uh nordvpn a lot of these other VPN this is not actually a ad from them to be very clear but uh if you're a big YouTube user you know that like Nord and express these sort of VPN companies are like major funders of like every YouTuber and it's really interesting to see how that marketing has changed over the past years I feel like initially it was very much focused on like oh like this will protect you from like you know your internet provider seeing your history and often that's still mentioned but actually most of the time now the emphasis of the ad reel is always on like you can watch Netflix in other countries you can like do this like new like you have this new affordance from using this VPN uh and that's always kind of like what they like talk about for a little bit longer and I feel like it is a very uh good representation of the fact that like I think users will generally respond to things that are value ads um and not purely sort of defensive measures against like a some sort of like threat um and to be clear like I'm very much a cipher Punk and I like deeply believe in this technology but at the same time I also believe that if we're not able to do this sort of like communication work uh we're not going to be able to get users the defense and safety that they deserve and so I want to talk through just a few different kind of like high level affordances that I think are worth leaning into and talking about more uh the first is idea that privacy is really ownership um and I think ownership is something that a lot of people feel all more viscerally with stuff like you know big social medias like hosting all your photos you don't own any songs anymore with spottify and I think there's a general sense of like this is something that people like don't have that they that they wish they did and in general I think like one really nice thing is that with cryptographic tools um with signatures uh with like sign data on all sorts of different things you get to actually like own your own data and like have it be verifiable but then if you want to actually maintain privacy on top of this like it Works hand inand with other tools like ZK and really like if you own something it is almost to some extent like private to you like you should be able to sort of like keep it to yourself unless you want to share it and a lot of cryptographic tools give you exactly that another is the idea of user consent and this comes up uh really interesting way with something called multi-party computation which is this cryptographic tool where multiple parties get to sort of do a computation on their private data um there's actually a really nice feature where if one of the parties like leaves the protocol or otherwise just decides to like um you know that they don't want to be a part of it uh no result is reached and I think this is actually a very nice like positive feature uh where it's usually viewed in a lot of protocols as like a bug where user consent is almost like mathematically required um and I think this is like an offensive useful thing that people would be able to understand know this idea of portability or interoperability or verifiability like they're all kind of the same thing and I think um bunch of really cool use cases of this like one is like portable social graphs um this is like an app experience that I've been building with my team where you're essentially tapping different folks and building a private social graph that also you can take with you to other apps As You Wish um and I think this is something that a lot of us are feeling now when we're like locked into sort of social medas that aren't really working for us anymore another really good example is just all personal data stuff like ZK email enables you to take things in your own email and basically make proofs about them share them with other people in a way that means they don't need to just live in one service and finally I think an underated one is efficiency um there's this new idea that we've been exploring called narrow casting which essentially basically if people do have their own ownership and privacy over their own data you can basically send messages in a way that will only be read by the people who like match this criteria and so in a sense you can actually use cryptography to more efficiently like like disperse information uh a way that's privacy preserving uh really quick uh where you can experience this we have a booth um downstairs my team cursive uh where we're showing an app experience that has a bunch of these different features baked in uh one thing I'll call out is something called private seter section which lets you see what you have in common with other folks and um yeah there's going to be some more features added in this is where it is in the booth and um yeah that's that's the talk