An Immunity Passport Scheme Based on the Dual-Blockchain Architecture for International Travel

<table class="table-group" id="tab2"><tr><td><table class="table"><tr><td class="thead-hr" colspan="6"><hr/></td></tr><tr class="thead"><td class="align_left" rowspan="2">Block header</td><td class="align_center" colspan="2">Timestamp</td><td class="align_center">Block ID</td><td class="align_center">Size</td><td class="align_center">Prehash</td></tr><tr class="thead"><td class="align_center" colspan="2"><span style="width: 4.54925ptpx;"><svg height="8.02022pt" id="M36" style="vertical-align:-0.2063999pt" version="1.1" viewbox="-0.0498162 -7.81382 4.54925 8.02022" width="4.54925pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M324 430H196L233 583L223 592L145 529L120 430H54L29 396L31 388H111L56 126C33 15 54 -12 77 -12C137 -12 214 57 250 95L233 119C208 92 155 59 138 59C126 59 120 70 131 125L186 390L298 394L324 430Z"></path></g></svg></span></td><td class="align_center"><span style="width: 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<div>Structure of transaction on the DBC.</div>

Wireless Communications and Mobile Computing

tab2

Table 2

Table 2: An Immunity Passport Scheme Based on the Dual-Blockchain Architecture for International Travel 