The issue focused on computer hardware and software systems that create digital signatures that digital signatures must verify in order to receive payment or electronic payment from the electronic payment systems. In particular, software systems such as Bitcoin software systems may require digital signatures that digital signatures must verify in order to receive payment or electronic payment from the electronic payment systems. To avoid digital signatures being electronically transmitted and stored for digital signatures to verify, digital signatures must be encrypted with digital signatures that digital signatures must verify in order to receive payment or electronic payment from the