Contents

- 1 What are the main differences between a group signature and a ring signature?
- 2 What is onetime signature scheme?
- 3 What is blind signature scheme?
- 4 What types of attacks can be performed on a signature scheme?
- 5 How do ring signatures work?
- 6 What is ring CT?
- 7 What is Lamport scheme?
- 8 What are hash based signatures?
- 9 Where are blind signatures used?
- 10 Does Bitcoin use blind signatures?
- 11 Can RSA signatures be forged?
- 12 What is a digital signature scheme?
- 13 How is a digital signature created?
- 14 Are ring signatures used in Bitcoin?
- 15 How do monero transactions work?

## What are the main differences between a group signature and a ring signature?

Ring signatures are similar to group signatures but differ in two key ways: first, there is no way to revoke the anonymity of an individual signature; and second, **any set of users can be used as a signing set without additional setup.**

## What is onetime signature scheme?

A one-time signature (OTS) scheme is **a digital signature scheme that can be used to sign one message per key pair**. More generally, we consider w-time signatures, which allow w signatures to be signed securely with each key pair (signing more than w messages breaks the security of the scheme).

## What is blind signature scheme?

A blind signature scheme is **a type of digital signature that conceals the identity of the message contents and the sender**. In these schemes the sender's message is concealed — or blinded — prior to the recipient signing it.

## What types of attacks can be performed on a signature scheme?

There are three types of attacks on Digital Signatures: Attention reader!…**Types of Digital Signature Attacks**

- Chosen-message Attack : The chosen attack method is of two types:
- Known-message Attack :
- Key-only Attack :

10-Apr-2020

## How do ring signatures work?

To produce a ring signature, **the actual signer declares an arbitrary set of possible signers that must include himself**, and computes the signature entirely by himself using only his secret key and the others' public keys.

## What is ring CT?

RingCT, **short for Ring Confidential Transactions**, is how transaction amounts are hidden in Monero. Ring CT was implemented in block #1220516 in January 2017. After September 2017, this feature became mandatory for all transactions on the network.

## What is Lamport scheme?

In cryptography, a Lamport signature or Lamport one-time signature scheme is **a method for constructing a digital signature**. Lamport signatures can be built from any cryptographically secure one-way function; usually a cryptographic hash function is used.

## What are hash based signatures?

Hash-based signature schemes **combine a one-time signature scheme with a Merkle tree structure**. … Since a one-time signature scheme key can only sign a single message securely, it is practical to combine many such keys within a single, larger structure. A Merkle tree structure is used to this end.

## Where are blind signatures used?

Blind signatures are typically employed in **privacy-related protocols where the signer and message author are different** parties. Examples include cryptographic election systems and digital cash schemes.

## Does Bitcoin use blind signatures?

Since **the blind signature is used**, the bitcoin provider cannot tell the relationship between the real identities of clients and the transacted bitcoins in the blockchain. The new blind signature is based on a variant of the Paillier cryptosystem.

## Can RSA signatures be forged?

Note that N is part of both the public and the private RSA key. … If all these conditions are there, the attacker is able, without any knowledge of the private key, to forge a RSA signature for **pretty much any message**, and have it accepted by the verifier.

## What is a digital signature scheme?

Digital signature schemes are **techniques to assure an entity's acknowledgment of having seen a certain digital message**. … The fact that the entity acknowledged, that is, that he signed the message, can be verified by anyone using the entity's public key, the message, and the signature.

## How is a digital signature created?

A digital signature is created **using hash algorithms or a scheme of algorithms like DSA and RSA that use public key and private key encryptions**. The sender uses the private key to sign the message digest (not the data), and when they do, it forms a digital thumbprint to send the data.

## Are ring signatures used in Bitcoin?

About ring signatures In 2015, Dr Shen Noether published an article entitled “Ring Confidential Transactions”, which laid the foundation for the ring signature algorithm implemented in Monero. Much like Bitcoin, this implementation of the signature algorithm uses a **“hash-based public key + private key” approach**.

## How do monero transactions work?

Monero uses ring signatures, zero-knowledge proofs, and "stealth addresses" to obfuscate transaction details. These features are baked into the protocol, though users can optionally share view keys for third party auditing. Transactions are validated through a **miner network running RandomX**, a proof of work algorithm.