{"id":33397,"date":"2023-12-08T02:29:03","date_gmt":"2023-12-08T02:29:03","guid":{"rendered":"https:\/\/masterskills.org\/blog\/ma-hoa-khoa-cong-cong-public-key-la-gi-thuan-loi-va-kho-khan.html"},"modified":"2023-12-23T11:28:45","modified_gmt":"2023-12-23T04:28:45","slug":"ma-hoa-khoa-cong-cong-public-key-la-gi-thuan-loi-va-kho-khan","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/ma-hoa-khoa-cong-cong-public-key-la-gi-thuan-loi-va-kho-khan.html","title":{"rendered":"M\u00e3 h\u00f3a kh\u00f3a c\u00f4ng c\u1ed9ng (Public key) l\u00e0 g\u00ec? Thu\u1eadn l\u1ee3i v\u00e0 kh\u00f3 kh\u0103n"},"content":{"rendered":"
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H\u00ecnh minh h\u1ecda (Ngu\u1ed3n: notebookbft)<\/p>\n<\/div>\n<\/div>\n

M\u00e3 h\u00f3a kh\u00f3a c\u00f4ng c\u1ed9ng<\/font><\/h2>\n

Kh\u00e1i ni\u1ec7m<\/b><\/p>\n

M\u00e3 h\u00f3a kh\u00f3a c\u00f4ng c\u1ed9ng<\/b> trong ti\u1ebfng Anh g\u1ecdi l\u00e0:\u00a0Public key.<\/b><\/p>\n

M\u00e3 h\u00f3a kh\u00f3a c\u00f4ng c\u1ed9ng (c\u00f2n g\u1ecdi l\u00e0 m\u00e3 h\u00f3a kh\u00f4ng \u0111\u1ed1i x\u1ee9ng)<\/b>\u00a0l\u00e0 vi\u1ec7c s\u1eed d\u1ee5ng hai m\u00e3 kh\u00f3a trong qu\u00e1 tr\u00ecnh m\u00e3 h\u00f3a: m\u1ed9t m\u00e3 kh\u00f3a d\u00f9ng \u0111\u1ec3 m\u00e3 h\u00f3a th\u00f4ng \u0111i\u1ec7p v\u00e0 m\u1ed9t kh\u00f3a kh\u00e1c d\u00f9ng \u0111\u1ec3 gi\u1ea3i m\u00e3.\u00a0<\/p>\n

Hai m\u00e3 kh\u00f3a n\u00e0y c\u00f3 quan h\u1ec7 v\u1edbi nhau v\u1ec1 m\u1eb7t thu\u1eadt to\u00e1n sao cho d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c m\u00e3 h\u00f3a b\u1eb1ng kh\u00f3a n\u00e0y s\u1ebd \u0111\u01b0\u1ee3c gi\u1ea3i m\u00e3 b\u1eb1ng kh\u00f3a kia.\u00a0<\/p>\n

Nh\u01b0 v\u1eady th\u1ef1c ch\u1ea5t, ph\u01b0\u01a1ng ph\u00e1p m\u00e3 h\u00f3a n\u00e0y d\u00f9ng m\u1ed9t c\u1eb7p m\u00e3 kh\u00f3a cho qu\u00e1 tr\u00ecnh m\u00e3 h\u00f3a: m\u1ed9t m\u00e3 kh\u00f3a g\u1ecdi l\u00e0 m\u00e3 kh\u00f3a c\u00f4ng c\u1ed9ng v\u00e0 m\u1ed9t l\u00e0 m\u00e3 kh\u00f3a ri\u00eang.\u00a0<\/p>\n

M\u00e3 kh\u00f3a c\u00f4ng c\u1ed9ng l\u00e0 m\u00e3 kh\u00f3a c\u00f3 th\u1ec3 c\u00f4ng khai cho nhi\u1ec1u ng\u01b0\u1eddi bi\u1ebft, c\u00f2n m\u00e3 kh\u00f3a ri\u00eang \u0111\u01b0\u1ee3c gi\u1eef b\u00ed m\u1eadt v\u00e0 ch\u1ec9 m\u00ecnh ch\u1ee7 nh\u00e2n c\u1ee7a n\u00f3 \u0111\u01b0\u1ee3c bi\u1ebft. T\u1ea5t nhi\u00ean, c\u1ea3 hai m\u00e3 kh\u00f3a n\u00e0y \u0111\u1ec1u \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7 tr\u00e1nh b\u1ecb \u0111\u00e1nh c\u1eafp ho\u1eb7c thay \u0111\u1ed5i.<\/p>\n

Thu\u1eadt ng\u1eef m\u1eadt m\u00e3 h\u00f3a kh\u00f3a b\u1ea5t \u0111\u1ed1i x\u1ee9ng th\u01b0\u1eddng \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ed3ng ngh\u0129a v\u1edbi m\u1eadt m\u00e3 h\u00f3a kh\u00f3a c\u00f4ng khai m\u1eb7c d\u00f9 hai kh\u00e1i ni\u1ec7m kh\u00f4ng ho\u00e0n to\u00e0n t\u01b0\u01a1ng \u0111\u01b0\u01a1ng.\u00a0<\/p>\n

C\u00f3 nh\u1eefng thu\u1eadt to\u00e1n m\u1eadt m\u00e3 kh\u00f3a b\u1ea5t \u0111\u1ed1i x\u1ee9ng kh\u00f4ng c\u00f3 t\u00ednh ch\u1ea5t kh\u00f3a c\u00f4ng khai v\u00e0 b\u00ed m\u1eadt nh\u01b0 \u0111\u1ec1 c\u1eadp \u1edf tr\u00ean m\u00e0 c\u1ea3 hai kh\u00f3a (cho m\u00e3 h\u00f3a v\u00e0 gi\u1ea3i m\u00e3) \u0111\u1ec1u c\u1ea7n ph\u1ea3i gi\u1eef b\u00ed m\u1eadt.\u00a0<\/p>\n

Trong m\u1eadt m\u00e3 h\u00f3a kh\u00f3a c\u00f4ng khai, kh\u00f3a c\u00e1 nh\u00e2n ph\u1ea3i \u0111\u01b0\u1ee3c gi\u1eef b\u00ed m\u1eadt trong khi kh\u00f3a c\u00f4ng khai \u0111\u01b0\u1ee3c ph\u1ed5 bi\u1ebfn c\u00f4ng khai. Trong 2 kh\u00f3a, m\u1ed9t d\u00f9ng \u0111\u1ec3 m\u00e3 h\u00f3a v\u00e0 kh\u00f3a c\u00f2n l\u1ea1i d\u00f9ng \u0111\u1ec3 gi\u1ea3i m\u00e3. \u0110i\u1ec1u quan tr\u1ecdng \u0111\u1ed1i v\u1edbi h\u1ec7 th\u1ed1ng l\u00e0 kh\u00f4ng th\u1ec3 t\u00ecm ra kh\u00f3a b\u00ed m\u1eadt n\u1ebfu ch\u1ec9 bi\u1ebft kh\u00f3a c\u00f4ng khai.\u00a0<\/p>\n

M\u1ee5c \u0111\u00edch<\/font><\/h3>\n

H\u1ec7 th\u1ed1ng m\u1eadt m\u00e3 h\u00f3a kh\u00f3a c\u00f4ng khai c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng v\u1edbi c\u00e1c m\u1ee5c \u0111\u00edch:<\/p>\n

M\u00e3 h\u00f3a<\/b>: gi\u1eef b\u00ed m\u1eadt th\u00f4ng tin v\u00e0 ch\u1ec9 c\u00f3 ng\u01b0\u1eddi c\u00f3 kh\u00f3a b\u00ed m\u1eadt m\u1edbi gi\u1ea3i m\u00e3 \u0111\u01b0\u1ee3c.\u00a0<\/p>\n

T\u1ea1o ch\u1eef k\u00ed s\u1ed1<\/b>: cho ph\u00e9p ki\u1ec3m tra m\u1ed9t v\u0103n b\u1ea3n c\u00f3 ph\u1ea3i \u0111\u00e3 \u0111\u01b0\u1ee3c t\u1ea1o v\u1edbi m\u1ed9t kh\u00f3a b\u00ed m\u1eadt n\u00e0o \u0111\u00f3 hay kh\u00f4ng.<\/p>\n

Th\u1ecfa thu\u1eadn kh\u00f3a<\/b>: cho ph\u00e9p thi\u1ebft l\u1eadp kh\u00f3a d\u00f9ng \u0111\u1ec3 trao \u0111\u1ed5i th\u00f4ng tin m\u1eadt gi\u1eefa 2 b\u00ean.\u00a0<\/p>\n

Th\u00f4ng th\u01b0\u1eddng, c\u00e1c k\u0129 thu\u1eadt m\u1eadt m\u00e3 h\u00f3a kh\u00f3a c\u00f4ng khai \u0111\u00f2i h\u1ecfi kh\u1ed1i l\u01b0\u1ee3ng t\u00ednh to\u00e1n nhi\u1ec1u h\u01a1n c\u00e1c k\u0129 thu\u1eadt m\u00e3 h\u00f3a kh\u00f3a \u0111\u1ed1i x\u1ee9ng nh\u01b0ng nh\u1eefng l\u1ee3i \u0111i\u1ec3m m\u00e0 ch\u00fang mang l\u1ea1i khi\u1ebfn cho ch\u00fang \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng trong nhi\u1ec1u \u1ee9ng d\u1ee5ng.<\/p>\n

Thu\u1eadn l\u1ee3i v\u00e0 kh\u00f3 kh\u0103n<\/font><\/h3>\n

– Thu\u1eadn l\u1ee3i<\/p>\n

C\u00e1c h\u1ec7 th\u1ed1ng kho\u00e1 c\u00f4ng khai mang l\u1ea1i m\u1ed9t s\u1ed1 thu\u1eadn l\u1ee3i, so v\u1edbi c\u00e1c gi\u1ea3i ph\u00e1p m\u00e3 ho\u00e1 kho\u00e1 ri\u00eang.<\/p>\n

+ Th\u1ee9 nh\u1ea5t, vi\u1ec7c k\u1ebft h\u1ee3p c\u00e1c kho\u00e1 (\u0111\u01b0\u1ee3c y\u00eau c\u1ea7u cung c\u1ea5p cho c\u00e1c th\u00f4ng b\u00e1o b\u00ed m\u1eadt gi\u1eefa m\u1ed9t s\u1ed1 l\u01b0\u1ee3ng ng\u01b0\u1eddi kh\u1ed5ng l\u1ed3) l\u00e0 nh\u1ecf. N\u1ebfu c\u00f3 N ng\u01b0\u1eddi mu\u1ed1n chia s\u1ebb th\u00f4ng tin v\u1edbi ng\u01b0\u1eddi kh\u00e1c m\u1ed9t c\u00e1ch b\u00ed m\u1eadt th\u00ec ch\u1ec9 c\u1ea7n duy nh\u1ea5t N c\u1eb7p kho\u00e1 c\u00f4ng khai, \u00edt h\u01a1n r\u1ea5t nhi\u1ec1u so v\u1edbi h\u1ec7 th\u1ed1ng kho\u00e1 ri\u00eang t\u01b0\u01a1ng \u0111\u01b0\u01a1ng.\u00a0<\/p>\n

+ Th\u1ee9 hai, vi\u1ec7c ph\u00e2n ph\u1ed1i kho\u00e1 kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t v\u1ea5n \u0111\u1ec1. Kho\u00e1 c\u00f4ng khai c\u1ee7a m\u1ed7i ng\u01b0\u1eddi c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c g\u1eedi \u0111i theo \u0111\u01b0\u1eddng b\u00ed m\u1eadt n\u1ebfu c\u1ea7n thi\u1ebft v\u00e0 kh\u00f4ng y\u00eau c\u1ea7u b\u1ea5t k\u00ec s\u1ef1 ki\u1ec3m so\u00e1t \u0111\u1eb7c bi\u1ec7t n\u00e0o khi ph\u00e2n ph\u1ed1i.\u00a0<\/p>\n

+ Th\u1ee9 ba, c\u00e1c h\u1ec7 th\u1ed1ng kho\u00e1 c\u00f4ng khai c\u00f3 kh\u1ea3 n\u0103ng th\u1ef1c thi ch\u1eef k\u00ed s\u1ed1. \u0110i\u1ec1u n\u00e0y c\u00f3 ngh\u0129a l\u00e0 m\u1ed9t t\u00e0i li\u1ec7u \u0111i\u1ec7n t\u1eed c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c k\u00ed v\u00e0 g\u1eedi cho ng\u01b0\u1eddi nh\u1eadn b\u1ea5t k\u00ec, c\u00f9ng v\u1edbi ch\u1ed1ng ch\u1ed1i b\u1ecf. C\u00f3 ngh\u0129a l\u00e0, v\u1edbi k\u0129 thu\u1eadt kho\u00e1 c\u00f4ng khai, kh\u00f3 c\u00f3 th\u1ec3 t\u1ed3n t\u1ea1i m\u1ed9t ng\u01b0\u1eddi n\u00e0o kh\u00e1c ngo\u00e0i ng\u01b0\u1eddi k\u00ed – sinh ra ch\u1eef k\u00ed \u0111i\u1ec7n t\u1eed;\u00a0<\/p>\n

Th\u00eam v\u00e0o \u0111\u00f3, ng\u01b0\u1eddi k\u00ed kh\u00f4ng th\u1ec3 ch\u1ed1i b\u1ecf vi\u1ec7c k\u00ed t\u00e0i li\u1ec7u sau khi \u0111\u00e3 k\u00ed.\u00a0<\/p>\n

– Kh\u00f3 kh\u0103n<\/p>\n

C\u00e1c h\u1ec7 th\u1ed1ng kho\u00e1\u00a0c\u00f4ng khai c\u00f3 m\u1ed9t s\u1ed1 kh\u00f3 kh\u0103n. M\u1ed9t trong c\u00e1c kh\u00f3 kh\u0103n \u0111\u00f3 l\u00e0 qu\u00e1 tr\u00ecnh m\u00e3 ho\u00e1 v\u00e0 gi\u1ea3i m\u00e3 kh\u00e1 ch\u1eadm so v\u1edbi c\u00e1c h\u1ec7 th\u1ed1ng kho\u00e1 ri\u00eang. Kho\u1ea3ng th\u1eddi gian ch\u00eanh l\u1ec7ch n\u00e0y s\u1ebd t\u0103ng l\u00ean m\u1ed9t c\u00e1ch nhanh ch\u00f3ng n\u1ebfu ti\u1ebfn h\u00e0nh th\u01b0\u01a1ng m\u1ea1i tr\u00ean Internet.\u00a0<\/p>\n

Ng\u01b0\u1eddi ta kh\u00f4ng c\u00f3 \u00fd \u0111\u1ecbnh thay th\u1ebf c\u00e1c h\u1ec7 th\u1ed1ng kho\u00e1 ri\u00eang b\u1eb1ng c\u00e1c h\u1ec7 th\u1ed1ng kho\u00e1 c\u00f4ng khai m\u00e0 s\u1eed d\u1ee5ng k\u1ebft h\u1ee3p \u0111\u1ec3 b\u1ed5 sung cho nhau. C\u00e1c h\u1ec7 th\u1ed1ng kho\u00e1 c\u00f4ng khai \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 truy\u1ec1n c\u00e1c kho\u00e1 ri\u00eang cho c\u00e1c th\u00e0nh vi\u00ean.\u00a0<\/p>\n

So s\u00e1nh ph\u01b0\u01a1ng ph\u00e1p m\u00e3 h\u00f3a kh\u00f3a c\u00f4ng c\u1ed9ng v\u1edbi\u00a0ph\u01b0\u01a1ng ph\u00e1p m\u00e3 h\u00f3a kh\u00f3a b\u00ed m\u1eadt, c\u1ea3 hai ph\u01b0\u01a1ng ph\u00e1p n\u00e0y \u0111\u1ec1u c\u00f3 nh\u1eefng \u01b0u v\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m ri\u00eang. Vi\u1ec7c s\u1eed d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p n\u00e0o s\u1ebd do ch\u00ednh c\u00e1c b\u00ean quy\u1ebft \u0111\u1ecbnh c\u0103n c\u1ee9 v\u00e0o m\u1ee9c \u0111\u1ed9 c\u1ea7n b\u1ea3o m\u1eadt v\u00e0 m\u00f4i tr\u01b0\u1eddng ho\u1ea1t \u0111\u1ed9ng giao d\u1ecbch.\u00a0<\/p>\n

Tuy nhi\u00ean, ph\u01b0\u01a1ng ph\u00e1p m\u00e3 h\u00f3a kh\u00f3a c\u00f4ng c\u1ed9ng r\u1ea5t ph\u00f9 h\u1ee3p khi c\u00f3 nhi\u1ec1u b\u00ean c\u00f9ng tham gia v\u00e0o qu\u00e1 tr\u00ecnh truy\u1ec1n th\u00f4ng tr\u00ean m\u1ea1ng b\u1edfi v\u00ec trong nh\u1eefng tr\u01b0\u1eddng h\u1ee3p nh\u01b0 v\u1eady, c\u00e1c b\u00ean r\u1ea5t kh\u00f3 c\u00f3 th\u1ec3 tin t\u01b0\u1edfng l\u1eabn nhau c\u0169ng nh\u01b0 kh\u00f3 c\u00f3 th\u1ec3 chia s\u1ebb c\u00f9ng m\u1ed9t m\u00e3 kh\u00f3a b\u00ed m\u1eadt.\u00a0<\/p>\n

\u0110\u00e2y ch\u00ednh l\u00e0 c\u00e1c \u0111\u1eb7c \u0111i\u1ec3m c\u01a1 b\u1ea3n c\u1ee7a c\u00e1c giao d\u1ecbch th\u01b0\u01a1ng m\u1ea1i \u0111i\u1ec7n t\u1eed tr\u00ean Internet.<\/p>\n

(T\u00e0i li\u1ec7u tham kh\u1ea3o: B\u00e0i gi\u1ea3ng Th\u01b0\u01a1ng m\u1ea1i \u0110i\u1ec7n t\u1eed, Tr\u1ea7n C\u00f4ng Nghi\u1ec7p, 2008, NXB Tr\u01b0\u1eddng \u0110\u1ea1i h\u1ecdc Kinh t\u1ebf v\u00e0 Qu\u1ea3n tr\u1ecb Kinh doanh)<\/i><\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

\n M\u00e3 h\u00f3a kh\u00f3a c\u00f4ng c\u1ed9ng (ti\u1ebfng Anh: Public key) l\u00e0 m\u1ed9t trong nh\u1eefng k\u0129 thu\u1eadt c\u01a1 b\u1ea3n \u0111\u1ec3 m\u00e3 h\u00f3a th\u00f4ng tin tr\u00ean Internet, v\u00e0 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 ph\u00f2ng tr\u00e1nh r\u1ee7i ro trong th\u01b0\u01a1ng m\u1ea1i \u0111i\u1ec7n t\u1eed.\n <\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[418],"tags":[],"_links":{"self":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/33397"}],"collection":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/comments?post=33397"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/33397\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=33397"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=33397"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=33397"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}