(IJCH) The "So What?" And "Who Cares?" of zk-SNARKS (And The Absolute Simplest Way to Explain It)
(IJCH) The "So What?" And "Who Cares?" of zk-SNARKS (And The Absolute Simplest Way to Explain It)
IJCH - Inside JaiChai's Head (meaning: My warped, personal opinions and musings)
From the Author:
Salutations.
I am JaiChai.
And if I haven't had the pleasure of meeting you before, I'm delighted to make your acquaintance now.
The "So What?" of zk-SNARKs
All blockchains are basically open ledgers where privacy is easily compromised.
Even in so-called "permissioned", private blockchains, a privileged individual can view the who, what and where of any transaction.
The majority of users prefer that their transactions remain confidential; hence, the proliferation of the many "privacy coins" such as:
The zk-SNARKs technology is considered the number one method for blockchains to keep all things private for its users.
What is the "zk" in zk-SNARKs?
The "zk" in zk-SNARKs stands for "ZERO KNOWLEDGE" proof.
It describes a scenario where one person needs to prove to another person that he possesses the correct, "secret" knowledge - WITHOUT DIVULGING THAT KNOWLEDGE.
For example, imagine you are a top secret courier that was sent on a dangerous, top secret, wartime mission to transport a crucial message to the General of your allied, friendly forces.
When you arrived at the General's base camp, you are stopped by the perimeter guards.
In order to complete your mission, you must prove that you are indeed authentic and possess the secret message - WITHOUT DIVULGING THE CONTENTS OF THE MESSAGE.
Zero Knowledge proofs are mathematical formula's that can solve this dilemma and have been incorporated into security algorithms.
Classical examples of Zero Knowledge scenarios include "Alibaba's Cave" and "Finding Waldo".
Zero Knowledge mathematical proofs have been around since the 1980's and was pioneered by Goldwasser, Micali and Rackoff from MIT.
Their revolutionary contribution to the study of Zero Knowledge proofs was that instead of questioning the honesty and authenticity of the prover (the one possessing the secret knowledge), they put more onus on the verifier of the proof (the General's guard) to validate authenticity.
What is the "SNARK" in zk-SNARKs?
"SNARK" stands for a mathematical proof that is a “Zero-Knowledge Succinct Non-Interactive Argument Knowledge" Proof.
See: https://en.wikipedia.org/wiki/Zero-knowledge_proof
Prior to 1986, all the Zero Knowledge proofs had one major efficiency flaw:
They all were interactive (meaning: both parties were required to be online at the same time).
This made implementing Zero Knowledge proofs impractical for large scale, online activity.
In short, very limited scalability.
But in 1986, Fiat and Shamir created the Fiat-Shamir heuristic that successfully solved the interactive problem and effectively made non-interactive zero knowledge proof based algorithms viable for global scalability.
Pleasing The Regulators
Systems (implementations) of zk-SNARKs (e.g., Zcash) have the ability for permissioned regulation; that is, when law enforcement or regulatory organizations request proof of compliance, a user has two methods to show it.
The first way is by using the "View Key" that only the user possesses.
If desired, the user can show all hidden transactions to whomever they want to see it.
The other method is "the memo field".
According to Zooko Wilcox (CEO of Zcash): “This memo could carry data between financial institutions wherever they are required by law to send that data along.”
These capabilities go a long way in pleasing regulators and enhancing mass adoption of Privacy Cryptocurrency.
The "Who Cares" of zk-SNARKs
The following Cryptocurrencies and Platforms are implementing (or planning to implement) zk-SNARKs - with many more sure to follow.
By JaiChai
Parting Shot
Thanks for stopping by.
About the Author
Believing that school was too boring, he dropped out of High School early; only to earn an AA, BS and MBA in less than 4 years much later in life – while working full-time as a Navy/Marine Corps Medic.
After 24 years of active duty, he retired in Asia.
Since then, he's been a full-time, single father and actively pursuing his varied passions (Writing, Disruptive Technology, Computer Science and Cryptocurrency - plus more hobbies too boring or bizarre for most folk).
He lives on an island paradise with his teenage daughter, longtime girlfriend and three dogs.
