<center style="font-size:30px"> <b>DISTRIBUTED IMMUTABLE DATA OBJECT</b> </center> <center style="font-size:30px"> DIDO </center> <center style="font-size:30px"> Reference Architecture (RA) </center> <center style="font-size:15px"> for </center> <center style="font-size:20px"> Cryptocurrencies, Blockchains, Distributed Ledgers and Tangles </center> <center> <i>Version 2.0</i> </center> <center> <i>June 2020</i> </center> <center style="font-size:12px"> R. W. “Nick” Stavros<br/> Ian T. Stavros<br/> Bryan Turek <br/> Char Wales </center> <center style="font-size:10px"> <b><i>Jackrabbit Consulting</i></b> </center> <center style="font-size:12px"> Marc Abrams<br/> John Black </center> <center style="font-size:10px"> <b><i>Harmonia Holdings, LLC</i></b> </center>