The Problem – Bloated Blockchains
Examination of the Boolberry block chain (28-Jul-2014) shows the average transaction size is 4065 bytes. Calculations show ring signatures take up an average of 55% of that size.
And these calculations are for a block chain where mixins are not widely used yet. When mixins are used ring signatures take up 60-90% of the transaction size.
Ordinary CryptoNote coins have to keep all the ring signatures, since it is not possible to prove that a transaction belongs to a block without them.
Boolberry solution: Cut Off the Ring Signatures
Once a transaction gets a lot of confirmations (say one year old transaction with hundreds of thousands confirmations) the ring signature is no longer needed… even if transaction’s output is not spent yet.
