06 - Network State Conference 2026 - Dev Ojha on Scaling Encrypted Money

Uh, hello everyone. Uh, I'm Dev. And today I'm going to talk about again how we scale Zcash. And first, like what's the origin of like what we all care about? Well, starts with the Bitcoin white paper. Peer-to-peer electronic cash. It's kind of the promise we're all made. And with Zcash, the goal is to actually fulfill this. So, what's going on? Bitcoin started with the promise of being digital cash. And there's this great Nick Carter post. The narratives change over time. Starting 2019, you'll never hear anyone call it digital cash. You'll start hearing it be called digital gold or store value. With Zcash, instead we started the opposite way. What do you need to be a perfect store value initially? You know, you have to be fully sovereign, and same as Bitcoin. And and then you need to be fully fungible, oh, and be able to hold this for many years. And now it's time to start adding scale to make a towards digital cash. Cool. So, cash has three non-negotiable properties. Well, I guess add being sovereign as a base point. Then, fungible. It also should be durable. It should hold up for the long term. And scale as in like if I'm paying with cash for coffee, it should not block Alice from paying Bob at somewhere else. Cool. So, fungible, fancy word, just means one Zec equals one Zec. I'm not going to spend too much time on this. So, I'll fast forward to scale. But TLR, the problem is Satoshi could not spend his coins. So, you know, good to get fungible, you have to do privacy at every layer of the stack. So, Zcash pioneered on-chain zero-knowledge proofs. And what's unique to Zcash is that we care about privacy at the RPC level and in your wallet software. So, this leads to work like private information retrieval and like using Tor or DC-Nets to hide your IPs. Okay, so going to skip this for durability, for just basically how do you security max? TLDR, you can already hold Zcash in If you just shield your Zcash, it's safe from like quantum computers in that if one comes, that's fine. You can prove your balance and get going. Okay, so scale is the last part. So, how much TPS do we need? Well, let's just look at Visa and MasterCard, two credit card networks. They uh have about 50K TPS of capacity and use about 10K TPS on average. So, today Zcash is like sub 10. So, how do we get there? Well, step one, Tachyon. Sean uh Bowe, co-founder of Zcash, just told you about how it works. So, Tachyon converts the scaling problem, uh at least at the chain level, from being uh this hard thing with how do you do a state growth, etc., to now just being scale like sensor bandwidth and your mempools. So, um we get a straightforward equation at the end of this. Every transaction is going to be 2 kilobytes big. We need 50K TPS. So, we need to build the do consensus on 100 megabytes per second. This is the same level of what Solana needs, and we want to do this in pure proof of work, which is great. Um we'll do things like faster block propagation and um do recursive aggregation of ZKPs in the mempool. There's another talk by Evan later here that goes through it. But, we do this with the new node software, Zokrates. So, there's one other really hard part about privacy, which is actually the the real bottleneck. How does your wallet figure out you got paid? These payments are anonymous, which means no one knows who it's from, who it's to, or how much is in it. So, yeah, how do you find out your transaction is to you? Well, normally in every other blockchain, your wallet just gives a server your address and says, "Hey, what's my balance?" The server learns exactly whose IP it is is and whose address it is and what its balance is. In Zcash, at any point, if there's a trade-off that sacrifices uh UX versus privacy, they always take the privacy maxing thing. So, today, you download every single transaction in history. Uh this kind of obviously doesn't scale. Now, let's work through the numbers of it. Today, if you just want a 100 TPS, you'd be your phone would have to download 2.5 gigs a day. 50K TPS is uh over a terabyte. And if you wanted to go post-quantum, you'd be downloading 8 terabytes a day. Obviously, it doesn't work. So, we use this new cryptographic technique called PIR that converts this 8 terabytes to less than 10 megs. Uh TLDR, the private PIR is a private key to value lookup. And uh you basically a server does a really big matrix mall, which is just what AI already needs, and then you can get uh privately fetch your balance. And what's cool is everything that we talked about is already happening. So, Visor is one of the premier wallets. It's got already gone ZK proving 20x faster and it's using PIR to protect your privacy. Yeah, and soon it'll be doing it for scale. So, uh on the chain side, there's an upgrade in like 27 days that 3x speeds up using the chain cuz uh look, it's not digital cash if it takes like tens of minutes. So, yeah, brief summary of how we get towards peer-to-peer electronic cash actually this time. Uh thanks everyone for your time and just try out private wallets.