April 12, 2024 8:41 pm

Deterministic Finality

Dash has deterministic, not probabilistic, finality for transactions! 🧠
This makes Dash much more certain and secure than cryptocurrencies which have to wait for block confirmations in order to be secure.

Yes: a Dash payment may be more secure than a Bitcoin transaction will ever be! 🤯

First, some definitions:

✍️Probabilistic Security: High likelihood that a payment won’t be reversed

✍️Deterministic Security: Certainty that a payment won’t be reversed

With Bitcoin and other proof-of-work mined coins in particular, miners build blocks on top of previous ones. The chain with the most accumulated proof-of-work is the valid one (others may be forked off).

The reason you wait for confirmations is probabilistic security: the deeper in a chain of blocks that a transaction it is, the lower the chance that a chain with a different outcome for the transaction will win out. But it’s always a possibility!

Dash is a proof-of-work chain and runs on exactly this setup. But it has a couple of different mechanisms built on top that offer deterministic security:

⚡️InstantSend: Locks in transactions instantly, making them deterministically unable to be reversed

⚡️ChainLocks: Locks in the first-seen block on the network, making it deterministically final and permanent

Chain reorganizations are always a risk in most of the crypto world, which is why exchanges, payment processors, wallets, etc. wait for confirmations, risk score transactions, and so on. This is probabilistic security.

But this is not necessary with Dash!

All a service has to do is configure their node (or use a supporting block explorer API like our favorite, Blockchair) to check for an InstantSend lock in mempool transactions, or a ChainLock on a block, to be completely sure that a payment is secure! 🤯

Lots of chains claim “fast/instant transactions” that don’t actually have this. Litecoin, Dogecoin, Bitcoin Cash, and more rely on probabilistic security, especially for unconfirmed payments. You make a payment and then wait until you feel comfortable assuming that it’ll be fine. But you’re never sure!

Improvements to these systems, such as double-spend proofs proposed in Bitcoin Cash, don’t change this. They watch for lower probability of a reversal, but don’t fundamentally change the model.

Even Bitcoin Cash was forced to improve a form of deterministic finality with 10-block rolling checkpoints, preventing a reorganization from lasting more than 10 blocks, when payments with more than 10 confirmations were at risk! 😱

Deterministic finality is universally recognized as what really matters.

Bitcoin has historically gotten a pass from this, because its large and established hashrate makes the probability of a significant block reorg extremely low at this point. But conditions could change. The bottom line is this:

A Dash payment is more final in under 2 seconds than a Bitcoin payment will ever be!

Still relatively few blockchains are like Dash and offer instant deterministic finality for payments. There are a few, and these chains will rise above the rest in the coming years.

Demand deterministic finality. It’s 2024. Anything less in this age is unacceptable. 🫳🎤

About the author

Marina Siradegyan

Communications and marketing at DCG. Huge fan of Dash. And cats.