Choose a privacy coin you’re unfamiliar with, answer these questions and post your answers below:
a. Name and Symbol
EPIC Cash (Epic Private Internet Cash)
Ticker symbol: EPIC
b. Is it a fork of another coin? Which one? When did it fork?
EPIC uses the MimbleWimble protocol and is a fork of Grin. EPIC forked from Grin codebase v1.1.0-beta.2 and went live on September 2, 2019.
c. What information is shielded, and how?
EPIC uses the same exact privacy model as Grin; whereby, Confidential Transactions and CoinJoin obfuscate transaction amounts as well as the sender/receiver relationships, Dandelion++ shields IP addresses, and wallet addresses don’t exist on MW—only TXOs.
d. What information is unshielded, and how?
The information unshielded on EPIC includes the used input, new outputs, transaction kernel, and the kernel offset. This information is available on the blockchain.
e. How could an attacker link Alice and Bob?
An attacker could potentially link Alice and Bob through some sort of a “Flashlight Attack” (as described by Ian Miers). Further, Ivan Bogatyy’s article “Breaking Mimblewimble’s Privacy Model” claimed to have performed such an attack; nevertheless, his results left much to be desired. He was able to pick up transactions prior to cut-through aggregation. Because addresses aren’t used in MimbleWimble and because IP addresses are hidden, this “attack” doesn’t mean much. That being said, it’s still an area where work should be done to enhance privacy.