Bootstrapping of FHE over the Integers with Large Message Space

<table class="fixed-width table-group" id="tab2"><tr><td><table class="table"><colgroup><col style="width:5.14em"/><col style="width:13.25em"/></colgroup><tr><td class="thead-hr" colspan="2"><hr/></td></tr><tr class="thead"><td class="align_left"> </td><td class="align_center"> the number of multiplications</td></tr><tr><td class="thead-hr" colspan="2"><hr/></td></tr><tr><td class="align_left"> [<a href="/journals/scn/2018/6520258/#B3" target="_blank">3</a>]</td><td class="align_center"><span style="width: 34.6919ptpx;"><svg height="11.5564pt" id="M394" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 34.6919 11.5564" width="34.6919pt" 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="M699 369C699 549 575 666 407 666C186 666 23 488 23 278C23 101 145 -16 312 -16C535 -16 699 153 699 369ZM600 373C600 210 500 19 321 19C186 19 120 129 120 272C120 450 232 631 399 631C541 631 600 522 600 373Z" id="g113-80"></path></g><g transform="matrix(.013,0,0,-0.013,9.387,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,13.885,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path></g><g transform="matrix(.013,0,0,-0.013,20.36,0)"><path d="M377 665C166 665 44 494 44 317C44 126 183 -15 363 -15C547 -15 695 118 695 333C695 533 546 665 377 665ZM355 630C491 630 593 515 593 304C593 112 496 22 385 22C245 22 146 157 146 345S244 630 355 630ZM502 225V442H471C464 375 459 369 411 369H326C278 368 273 374 266 442H235V225H266C273 292 278 299 326 299H411C459 299 464 292 471 225H502Z" id="g113-137"></path></g><g transform="matrix(.013,0,0,-0.013,29.967,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z" id="g113-42"></path></g></svg></span></td></tr><tr><td class="align_left">[<a href="/journals/scn/2018/6520258/#B4" target="_blank">4</a>]</td><td class="align_center"><span style="width: 29.9952ptpx;"><svg height="13.8595pt" id="M395" style="vertical-align:-2.2681pt" version="1.1" viewbox="-0.0498162 -11.5914 29.9952 13.8595" width="29.9952pt" 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="M699 369C699 549 575 666 407 666C186 666 23 488 23 278C23 101 145 -16 312 -16C535 -16 699 153 699 369ZM600 373C600 210 500 19 321 19C186 19 120 129 120 272C120 450 232 631 399 631C541 631 600 522 600 373Z" id="g113-80"></path></g><g transform="matrix(.013,0,0,-0.013,9.387,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,13.885,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path></g><g transform="matrix(.0091,0,0,-0.0091,20.36,-5.741)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z" id="g50-51"></path></g><g transform="matrix(.013,0,0,-0.013,25.307,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z" id="g113-42"></path></g></svg></span></td></tr><tr><td class="align_left">[<a href="/journals/scn/2018/6520258/#B8" target="_blank">8</a>]</td><td class="align_center">  <svg height="14.9752pt" id="M396" style="vertical-align:-3.3838pt" version="1.1" viewbox="-0.0498162 -11.5914 60.0595 14.9752" width="60.0595pt" 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="M699 369C699 549 575 666 407 666C186 666 23 488 23 278C23 101 145 -16 312 -16C535 -16 699 153 699 369ZM600 373C600 210 500 19 321 19C186 19 120 129 120 272C120 450 232 631 399 631C541 631 600 522 600 373Z" id="g113-80"></path></g><g transform="matrix(.013,0,0,-0.013,9.387,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,13.885,0)"><path d="M377 665C166 665 44 494 44 317C44 126 183 -15 363 -15C547 -15 695 118 695 333C695 533 546 665 377 665ZM355 630C491 630 593 515 593 304C593 112 496 22 385 22C245 22 146 157 146 345S244 630 355 630ZM502 225V442H471C464 375 459 369 411 369H326C278 368 273 374 266 442H235V225H266C273 292 278 299 326 299H411C459 299 464 292 471 225H502Z" id="g113-137"></path></g><g transform="matrix(.013,0,0,-0.013,25.671,0)"><path d="M238 0V26C174 32 166 38 166 104V712C132 700 70 683 18 677V653C81 647 87 645 87 577V104C87 38 78 32 15 26V0H238Z" id="g121-106"></path></g><g transform="matrix(.013,0,0,-0.013,28.96,0)"><path d="M257 449C165 449 37 374 37 209C37 98 119 -12 256 -12C355 -12 473 65 473 226C473 349 381 449 257 449ZM244 416C333 416 380 320 380 204C380 67 329 21 267 21C184 21 130 115 130 241C130 354 184 416 244 416Z" id="g121-109"></path></g><g transform="matrix(.013,0,0,-0.013,35.59,0)"><path d="M463 437C426 431 375 425 327 422C297 440 264 449 231 449H230C153 449 51 396 51 283C51 215 94 168 139 149C123 129 91 103 51 88C50 78 53 60 62 46C75 25 100 2 136 -9C112 -28 73 -59 53 -79C38 -94 29 -113 29 -135C30 -192 91 -257 203 -257C336 -257 452 -160 452 -59C452 39 371 59 309 59C275 59 240 58 203 58C158 58 140 77 140 96C140 110 157 129 170 138C186 135 205 133 221 133C306 133 396 185 396 293C396 328 384 360 366 381L423 378C439 387 459 413 468 429L463 437ZM219 418C277 418 314 362 314 284C314 205 275 166 231 165C176 165 137 221 137 299C137 376 177 418 219 418ZM241 -11C285 -11 314 -14 339 -24C367 -36 384 -61 384 -95C384 -157 335 -206 240 -206C166 -206 108 -165 108 -110C108 -82 128 -54 154 -32C172 -17 195 -11 241 -11Z" id="g121-101"></path></g><g transform="matrix(.0091,0,0,-0.0091,41.674,-5.741)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z" id="g50-51"></path></g><g transform="matrix(.013,0,0,-0.013,48.8,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path></g><g transform="matrix(.013,0,0,-0.013,55.275,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z" id="g113-42"></path></g></svg></td></tr><tr><td class="align_left">[<a href="/journals/scn/2018/6520258/#B15" target="_blank">15</a>]</td><td class="align_center">  <svg height="14.9752pt" id="M397" style="vertical-align:-3.3838pt" version="1.1" viewbox="-0.0498162 -11.5914 48.2374 14.9752" width="48.2374pt" 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="M699 369C699 549 575 666 407 666C186 666 23 488 23 278C23 101 145 -16 312 -16C535 -16 699 153 699 369ZM600 373C600 210 500 19 321 19C186 19 120 129 120 272C120 450 232 631 399 631C541 631 600 522 600 373Z" id="g113-80"></path></g><g transform="matrix(.013,0,0,-0.013,9.387,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,13.885,0)"><path d="M238 0V26C174 32 166 38 166 104V712C132 700 70 683 18 677V653C81 647 87 645 87 577V104C87 38 78 32 15 26V0H238Z" id="g121-106"></path></g><g transform="matrix(.013,0,0,-0.013,17.174,0)"><path d="M257 449C165 449 37 374 37 209C37 98 119 -12 256 -12C355 -12 473 65 473 226C473 349 381 449 257 449ZM244 416C333 416 380 320 380 204C380 67 329 21 267 21C184 21 130 115 130 241C130 354 184 416 244 416Z" id="g121-109"></path></g><g transform="matrix(.013,0,0,-0.013,23.804,0)"><path d="M463 437C426 431 375 425 327 422C297 440 264 449 231 449H230C153 449 51 396 51 283C51 215 94 168 139 149C123 129 91 103 51 88C50 78 53 60 62 46C75 25 100 2 136 -9C112 -28 73 -59 53 -79C38 -94 29 -113 29 -135C30 -192 91 -257 203 -257C336 -257 452 -160 452 -59C452 39 371 59 309 59C275 59 240 58 203 58C158 58 140 77 140 96C140 110 157 129 170 138C186 135 205 133 221 133C306 133 396 185 396 293C396 328 384 360 366 381L423 378C439 387 459 413 468 429L463 437ZM219 418C277 418 314 362 314 284C314 205 275 166 231 165C176 165 137 221 137 299C137 376 177 418 219 418ZM241 -11C285 -11 314 -14 339 -24C367 -36 384 -61 384 -95C384 -157 335 -206 240 -206C166 -206 108 -165 108 -110C108 -82 128 -54 154 -32C172 -17 195 -11 241 -11Z" id="g121-101"></path></g><g transform="matrix(.0091,0,0,-0.0091,29.888,-5.741)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z" id="g50-51"></path></g><g transform="matrix(.013,0,0,-0.013,37.014,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path></g><g transform="matrix(.013,0,0,-0.013,43.489,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z" id="g113-42"></path></g></svg></td></tr><tr><td class="align_left">[<a href="/journals/scn/2018/6520258/#B16" target="_blank">16</a>]</td><td class="align_center">  <svg height="11.9413pt" id="M398" style="vertical-align:-0.3499002pt" version="1.1" viewbox="-0.0498162 -11.5914 57.5367 11.9413" width="57.5367pt" 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="M377 665C166 665 44 494 44 317C44 126 183 -15 363 -15C547 -15 695 118 695 333C695 533 546 665 377 665ZM355 630C491 630 593 515 593 304C593 112 496 22 385 22C245 22 146 157 146 345S244 630 355 630ZM502 225V442H471C464 375 459 369 411 369H326C278 368 273 374 266 442H235V225H266C273 292 278 299 326 299H411C459 299 464 292 471 225H502Z" id="g113-137"></path></g><g transform="matrix(.0091,0,0,-0.0091,9.607,-5.741)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z" id="g50-51"></path></g><g transform="matrix(.013,0,0,-0.013,17.459,0)"><path d="M535 230V280H323V490H265V280H52V230H265V-3H323V230H535Z" id="g117-36"></path></g><g transform="matrix(.013,0,0,-0.013,27.995,0)"><path d="M377 665C166 665 44 494 44 317C44 126 183 -15 363 -15C547 -15 695 118 695 333C695 533 546 665 377 665ZM355 630C491 630 593 515 593 304C593 112 496 22 385 22C245 22 146 157 146 345S244 630 355 630ZM502 225V442H471C464 375 459 369 411 369H326C278 368 273 374 266 442H235V225H266C273 292 278 299 326 299H411C459 299 464 292 471 225H502Z" id="g113-137"></path></g><g transform="matrix(.013,0,0,-0.013,40.508,0)"><path d="M535 230V280H323V490H265V280H52V230H265V-3H323V230H535Z" id="g117-36"></path></g><g transform="matrix(.013,0,0,-0.013,51.044,0)"><path d="M384 0V27C293 34 287 42 287 114V635C232 613 172 594 109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z" id="g113-50"></path></g></svg></td></tr><tr><td class="align_left">our result</td><td class="align_center"><span style="width: 51.9683ptpx;"><svg height="12.6721pt" id="M399" style="vertical-align:-3.38377pt" version="1.1" viewbox="-0.0498162 -9.28833 51.9683 12.6721" width="51.9683pt" 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="M699 369C699 549 575 666 407 666C186 666 23 488 23 278C23 101 145 -16 312 -16C535 -16 699 153 699 369ZM600 373C600 210 500 19 321 19C186 19 120 129 120 272C120 450 232 631 399 631C541 631 600 522 600 373Z" id="g113-80"></path></g><g transform="matrix(.013,0,0,-0.013,9.387,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path></g><g transform="matrix(.013,0,0,-0.013,13.885,0)"><path d="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z" id="g113-230"></path></g><g transform="matrix(.013,0,0,-0.013,22.54,0)"><path d="M238 0V26C174 32 166 38 166 104V712C132 700 70 683 18 677V653C81 647 87 645 87 577V104C87 38 78 32 15 26V0H238Z" id="g121-106"></path></g><g transform="matrix(.013,0,0,-0.013,25.828,0)"><path d="M257 449C165 449 37 374 37 209C37 98 119 -12 256 -12C355 -12 473 65 473 226C473 349 381 449 257 449ZM244 416C333 416 380 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<div>The number of multiplications in the decryption circuit.</div>

Security and Communication Networks

tab2

Table 2

Table 2: Bootstrapping of FHE over the Integers with Large Message Space 