hush
/
sietch
8
0
Fork 0
Code Issues 1 Pull Requests Projects Releases Wiki Activity
Sietch - technology to reduce metadata leakage of Zcash Protocol transactions https://hush.is
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
2 Commits
2 Branches
0 Tags
80 KiB
Tree: a8f8ccbd8b
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'a8f8ccbd8b'
${ noResults }
sietch/README.md

2.3 KiB
Raw Blame History

Byrsa

A walled citadel on a hill for your shielded funds.

What is Byrsa?

Byrsa is a new set of RPC functionality and consensus rules for using shielded funds, which do not currently modify the internals of the Zcash Protocol, but sit on top of it. It defines certain wallet and transction conditions that must be upheld for transactions to be accepted by the network.

How is Byrsa implemented?

Mostly it's done directly in C++ the hushd full node, which means all GUI wallets can benefit from it. Some features are implemented at the GUI wallet level. The goal is that the user does not need to think or do anything different, to have more privacy when making transactions.

From the perspective of the average GUI wallet user, It Just Works. There are no additional mandatory steps for the user when sending each transaction. There will be some options for advanced users, to tweak the settings, but using them is not required for increased privacy. They will mostly serve as ways for developers to experiment and optimize things.

What are the goals of Byrsa?

  • Make linkability analysis of zaddrs drastically more expensive
  • Allow people to make zaddr xtns safely/privately without thinking about metadata leakage or advanced techniques
  • Prevent average users from making some blockchain operations which give out too much metadata
  • Break some assumptions which many blockchain analyst software uses
  • Require blockchain analysts to write new software
  • Increase the privacy of all funds in the shielded pool
  • Introduce non-determinism to prevent ITM/Metaverse style metadata attacks

What are the limitations/downsides of Byrsa?

The goal of Byrsa is increased privacy and the cost is increased blockspace usage per transaction, increased CPU time and RAM to validate transcations and as a secondary effect, increased sync times.

Byrsa potentially adds inputs and outputs to transactions to increase their privacy, and so the maximum number of actual recipients is lower when Byrsa is enabled. In practice, transactions can still send to over 1000 recipients even with Byrsa protections, so it doesn't actually effect any current users, as far as we know.

How much longer will average xtn take? More RAM? No!

Implementation Details

These RPCs are modified:

	z_sendmany
	z_shieldcoinbase
	z_mergetoaddress