First step towards Schnorr Signature

Leo Zhang

By Leo Zhang

A formal Bitcoin Improvement Proposal for the hightly anticipated Schnorr Signature has just been submitted by Bitcoin Core developer Pieter Wuille. Schnorr is a digital signature scheme that leverages elliptic curve cryptography to allow the Bitcoin network to validate transactions submitted to it. Theoretically, Schnorr Signature may increase performance over the current ECDSA signatures currently used in Bitcoin (see story below).

As Pieter Wuille pointed out in an email to the Bitcoin-dev mailing list,this proposal is just a specification for the signature scheme itself. Integration into Bitcoin remains open for future proposals. The process of bringing Schnorr to be fully production ready is a lengthy process (related video below). This BIP is an important improvement; getting it adopted. implemented, and deployed will disprove naysayers who claim Bitcoin is locked in powerless in the face of political debate.

Schnorr BIP submission

"Bitcoin has traditionally used ECDSA signatures over the secp256k1 curve for authenticating transactions. These are standardized, but have a number of downsides compared to Schnorr signatures over the same curve:

  • Security proof: The security of Schnorr signatures is easily provable in the random oracle model assuming the elliptic curve discrete logarithm problem (ECDLP) is hard. Such a proof does not exist for ECDSA.
  • Non-malleability: ECDSA signatures are inherently malleable; a third party without access to the private key can alter an existing valid signature for a given public key and message into another signature that is valid for the same key and message. This issue is discussed in BIP62. On the other hand, Schnorr signatures are provably non-malleable.
  • Linearity: Schnorr signatures have the remarkable property that multiple parties can collaborate to produce a signature that is valid for the sum of their public keys. This is the building block for various higher-level constructions that improve efficiency and privacy, such as multisignatures and others."

Reddit discussion thread


Schnorr Signatures for Bitcoin: challenges and opportunities - BPASE'18

Why Schnorr Signatues will help solve 2 of Bitcoin's biggest problems today
(Sam Wouters)

"After over a year of testing, SegWit now has widespread support across all stakeholder groups (Developers, Users, Miners and Businesses) and will soon be implemented. This opens the door for one of the next innovations: Schnorr Signatures, which can further help to improve scalability."

Technical Updates

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"The wallet implements a trustless Bitcoin mixing technique, called Chaumian CoinJoin and enforces constant 100 anonymity set. This means waiting for peers may take a long time until liquidity catches up, no anonymity system used today in any cryptocurrency comes close to this number."

Tokenize it with Bitcoin! Giacomo Zucco unveils Lightning asset protocol
(Bitcoinist, by Wilma Woo)

"Almost anything can be integrated, worst case by importing bitcoins utxo into a v2 protocol and new network. This is why I don’t think feature coins have a long term value."

Zcash weekly engineering update
(Zcash, by mdr0id)

"This week, the engineering team completed their hybrid Zcon0 sprint. Zcon0 provided a ton of valuable input from the community, which we intend to integrate into upcoming sprints. You can view each team’s progress in Github projects 1. Other equally important items, Overwinter successfully activated on June 25th and v1.1.2 was released."

Get ready for ZenCash Super Node beta!
(ZenCash Blog)

"The Testnet tracking servers can be used to test Super Nodes even though they are set for Secure Nodes. Super Nodes use the exact same code as Secure Nodes and are just configured differently and require a different stake amount."

Microsoft Azure launches tamper-proof Azure immutable blob storage for financial services
(Microsoft, by Alan Ross)

"Software providers and partners can now rely on Azure as a one-stop shop cloud solution for records retention and immutable storage with sensitive workloads. Financial institutions can now easily build their own applications taking advantage of these features while remaining compliant. These Write Once Read Many (WORM) policies apply to all tiers of storage (hot, cool, and archive)."

“Stylish” extension with 2M downloads banned for tracking every site visit
(arsTechnica, by Dan Goodin)

"Google, Mozilla, and Opera have pulled a browser extension with more than two million downloads after it was caught tracking every website its users visited—and sending the data to a remote server."

News & Commentary

'A new era for capital markets': The Swiss stock exchange is launching its own cryptocurrency exchange
(Business Insider, by Oscar Williams-Grut)

"SIX's decision to launch a crypto exchange comes despite a collapse in the value of cryptocurrencies and declining volumes since the start of the year. Bitcoin, the largest crypto asset by market value, collapsed from around $20,000 per token at the start of the year to just over $6,600 on Thursday."

Mining giant Bitmain valued at $12 billion in new funding round
(CoinDesk, by Wolfie Zhao)

"Bitcoin mining giant Bitmain has reportedly closed a Series B funding round that values the firm at approximately $12 billion."