{"id":8192,"date":"2024-06-03T15:24:00","date_gmt":"2024-06-03T08:24:00","guid":{"rendered":"https:\/\/base.vn\/blog\/?p=8192"},"modified":"2025-08-09T11:06:17","modified_gmt":"2025-08-09T04:06:17","slug":"chu-ky-so-la-gi","status":"publish","type":"post","link":"https:\/\/base.vn\/blog\/chu-ky-so-la-gi\/","title":{"rendered":"Ch\u1eef k\u00fd s\u1ed1 l\u00e0 g\u00ec? Ki\u1ebfn th\u1ee9c quan tr\u1ecdng c\u1ea7n bi\u1ebft v\u1ec1 ch\u1eef k\u00fd s\u1ed1"},"content":{"rendered":"\n

V\u1edbi xu h\u01b0\u1edbng s\u1ed1 h\u00f3a quy tr\u00ecnh l\u00e0m vi\u1ec7c, ch\u1eef k\u00fd s\u1ed1<\/strong> c\u0169ng ng\u00e0y c\u00e0ng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i trong c\u00e1c t\u1ed5 ch\u1ee9c v\u00e0 doanh nghi\u1ec7p. Kh\u00f4ng ch\u1ec9 c\u00e1c t\u1eadp \u0111o\u00e0n l\u1edbn, m\u00e0 ngay c\u1ea3 c\u00e1c doanh nghi\u1ec7p nh\u1ecf c\u0169ng b\u1eaft \u0111\u1ea7u quan t\u00e2m \u0111\u1ebfn ph\u01b0\u01a1ng th\u1ee9c k\u00fd k\u1ebft hi\u1ec7n \u0111\u1ea1i, ti\u1ec7n l\u1ee3i v\u00e0 b\u1ea3o m\u1eadt n\u00e0y.<\/p>\n\n\n\n

V\u1eady ch\u1eef k\u00fd s\u1ed1 l\u00e0 g\u00ec? Gi\u00e1 tr\u1ecb ph\u00e1p l\u00fd c\u1ee7a ch\u1eef k\u00fd s\u1ed1 \u0111\u01b0\u1ee3c ph\u00e1p lu\u1eadt c\u00f4ng nh\u1eadn ra sao? V\u00e0 doanh nghi\u1ec7p c\u1ea7n l\u00e0m g\u00ec \u0111\u1ec3 s\u1eed d\u1ee5ng ch\u1eef k\u00fd s\u1ed1 m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3? H\u00e3y c\u00f9ng Base Blog<\/a> gi\u1ea3i \u0111\u00e1p t\u1ea5t c\u1ea3 nh\u1eefng th\u1eafc m\u1eafc n\u00e0y trong b\u00e0i vi\u1ebft sau \u0111\u00e2y.<\/p>\n\n\n\n

1. Ch\u1eef k\u00fd s\u1ed1 l\u00e0 g\u00ec?<\/strong> <\/strong><\/strong> <\/strong><\/strong> <\/strong><\/strong><\/h2>\n\n\n\n

1.1 \u0110\u1ecbnh ngh\u0129a<\/strong><\/h3>\n\n\n\n

Ch\u1eef k\u00fd s\u1ed1<\/strong> l\u00e0 m\u1ed9t thi\u1ebft b\u1ecb \u0111\u00e3 m\u00e3 h\u00f3a to\u00e0n b\u1ed9 d\u1eef li\u1ec7u v\u00e0 th\u00f4ng tin c\u1ee7a c\u00e1 nh\u00e2n ho\u1eb7c doanh nghi\u1ec7p b\u1eb1ng kh\u00f3a ri\u00eang c\u1ee7a ch\u1ee7 s\u1edf h\u1eefu, d\u00f9ng \u0111\u1ec3 k\u00fd k\u1ebft c\u00e1c lo\u1ea1i v\u0103n b\u1ea3n v\u00e0 t\u00e0i li\u1ec7u tr\u1ef1c tuy\u1ebfn. \u0110i\u1ec1u n\u00e0y \u0111\u1ea3m b\u1ea3o ng\u01b0\u1eddi nh\u1eadn c\u00f3 th\u1ec3 x\u00e1c \u0111\u1ecbnh v\u00e0 x\u00e1c th\u1ef1c \u0111\u00fang ngu\u1ed3n g\u1ed1c, c\u0169ng nh\u01b0 \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u nh\u1eadn \u0111\u01b0\u1ee3c.<\/p>\n\n\n\n

Khi s\u1eed d\u1ee5ng ch\u1eef k\u00fd s\u1ed1, doanh nghi\u1ec7p c\u1ea7n quan t\u00e2m \u0111\u1ebfn hai lo\u1ea1i kh\u00f3a do nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 x\u00e1c th\u1ef1c ch\u1eef k\u00fd s\u1ed1 (Certifying Authority – CA) c\u1ea5p.<\/p>\n\n\n\n

T\u1ea1i Vi\u1ec7t Nam, ch\u1eef k\u00fd s\u1ed1 \u0111\u00e3 \u0111\u01b0\u1ee3c ph\u00e1p lu\u1eadt c\u00f4ng nh\u1eadn v\u1ec1 m\u1eb7t ph\u00e1p l\u00fd, c\u00f3 gi\u00e1 tr\u1ecb t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u00e0 c\u00f3 th\u1ec3 thay th\u1ebf cho ch\u1eef k\u00fd tay c\u1ee7a c\u00e1 nh\u00e2n ho\u1eb7c con d\u1ea5u \u0111\u1ecf c\u1ee7a doanh nghi\u1ec7p. M\u1ed9t s\u1ed1 \u0111\u01a1n v\u1ecb cung c\u1ea5p d\u1ecbch v\u1ee5 ch\u1ee9ng th\u1ef1c ch\u1eef k\u00fd s\u1ed1 (CA) uy t\u00edn g\u1ed3m c\u00f3: VNPT-CA, CA2, BKAV-CA, VIETTEL-CA, FPT-CA, NEWTEL-CA, SAFE-CA, EFY-CA,\u2026<\/p>\n\n\n

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\"Ch\u1eef<\/figure><\/div>\n\n\n

1.2 C\u1ea5u t\u1ea1o c\u1ee7a ch\u1eef k\u00fd s\u1ed1<\/strong><\/h3>\n\n\n\n

Ch\u1eef k\u00fd s\u1ed1 \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp tr\u00ean n\u1ec1n t\u1ea3ng c\u00f4ng ngh\u1ec7 m\u1eadt m\u00e3 kh\u00f3a c\u00f4ng khai RSA (m\u1eadt m\u00e3 kh\u00f4ng \u0111\u1ed1i x\u1ee9ng). Khi \u0111\u01b0\u1ee3c c\u1ea5p v\u00e0 s\u1eed d\u1ee5ng ch\u1eef k\u00fd s\u1ed1, ng\u01b0\u1eddi d\u00f9ng s\u1ebd s\u1edf h\u1eefu m\u1ed9t kh\u00f3a c\u00f4ng khai (public key) v\u00e0 m\u1ed9t kh\u00f3a b\u00ed m\u1eadt (private key).<\/p>\n\n\n\n

Kh\u00f3a b\u00ed m\u1eadt (private key)<\/td>\u0110\u00e2y l\u00e0 th\u00e0nh ph\u1ea7n \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 t\u1ea1o ch\u1eef k\u00fd s\u1ed1. Kh\u00f3a b\u00ed m\u1eadt thu\u1ed9c h\u1ec7 th\u1ed1ng m\u00e3 h\u00f3a kh\u00f4ng \u0111\u1ed1i x\u1ee9ng v\u00e0 ch\u1ec9 ch\u1ee7 s\u1edf h\u1eefu m\u1edbi c\u00f3 quy\u1ec1n truy c\u1eadp v\u00e0 s\u1eed d\u1ee5ng n\u00f3.<\/td><\/tr>
Kh\u00f3a c\u00f4ng khai (public key)<\/td>\u0110\u00e2y l\u00e0 th\u00e0nh ph\u1ea7n \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 ki\u1ec3m tra ch\u1eef k\u00fd s\u1ed1. Kh\u00f3a c\u00f4ng khai thu\u1ed9c h\u1ec7 th\u1ed1ng m\u00e3 h\u00f3a c\u00f4ng khai v\u00e0 \u0111\u01b0\u1ee3c t\u1ea1o ra t\u1eeb kh\u00f3a b\u00ed m\u1eadt t\u01b0\u01a1ng \u1ee9ng. B\u1ea5t k\u1ef3 ai c\u0169ng c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng n\u00f3 \u0111\u1ec3 x\u00e1c th\u1ef1c ch\u1eef k\u00fd s\u1ed1.<\/td><\/tr>
Ng\u01b0\u1eddi k\u00fd<\/td>Ch\u1ee7 th\u1ec3 hay thu\u00ea bao c\u1ee7a kh\u00f3a b\u00ed m\u1eadt, th\u01b0\u1eddng l\u00e0 m\u1ed9t doanh nghi\u1ec7p ho\u1eb7c c\u00e1 nh\u00e2n. H\u1ecd s\u1ebd s\u1eed d\u1ee5ng kh\u00f3a b\u00ed m\u1eadt c\u1ee7a m\u00ecnh \u0111\u1ec3 k\u00fd s\u1ed1 v\u00e0o m\u1ed9t th\u00f4ng \u0111i\u1ec7p d\u1eef li\u1ec7u d\u01b0\u1edbi t\u00ean c\u1ee7a h\u1ecd.<\/td><\/tr>
Ng\u01b0\u1eddi nh\u1eadn<\/td>Doanh nghi\u1ec7p ho\u1eb7c c\u00e1 nh\u00e2n nh\u1eadn th\u00f4ng \u0111i\u1ec7p d\u1eef li\u1ec7u \u0111\u00e3 \u0111\u01b0\u1ee3c k\u00fd s\u1ed1. H\u1ecd s\u1ebd s\u1eed d\u1ee5ng ch\u1ee9ng th\u01b0 s\u1ed1 c\u1ee7a ng\u01b0\u1eddi k\u00fd \u0111\u1ec3 ki\u1ec3m tra v\u00e0 x\u00e1c th\u1ef1c ch\u1eef k\u00fd s\u1ed1 trong th\u00f4ng \u0111i\u1ec7p nh\u1eadn \u0111\u01b0\u1ee3c tr\u01b0\u1edbc khi ti\u1ebfn h\u00e0nh c\u00e1c ho\u1ea1t \u0111\u1ed9ng ho\u1eb7c giao d\u1ecbch li\u00ean quan.<\/td><\/tr>
K\u00fd s\u1ed1<\/td>\u0110\u00e2y l\u00e0 qu\u00e1 tr\u00ecnh c\u1eafm ho\u1eb7c \u0111\u01b0a kh\u00f3a b\u00ed m\u1eadt v\u00e0o m\u1ed9t ph\u1ea7n m\u1ec1m \u0111\u1ec3 ph\u1ea7n m\u1ec1m t\u1ea1o ra v\u00e0 g\u1eafn ch\u1eef k\u00fd s\u1ed1 v\u00e0o m\u1ed9t th\u00f4ng \u0111i\u1ec7p d\u1eef li\u1ec7u c\u1ee5 th\u1ec3.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

RSA (Rivest-Shamir-Adleman) l\u00e0 m\u1ed9t thu\u1eadt to\u00e1n m\u1eadt m\u00e3 h\u00f3a kh\u00f3a c\u00f4ng khai, \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 m\u00e3 h\u00f3a v\u00e0 gi\u1ea3i m\u00e3 d\u1eef li\u1ec7u, k\u00fd s\u1ed1 v\u00e0 x\u00e1c minh ch\u1eef k\u00fd s\u1ed1 trong c\u00e1c l\u0129nh v\u1ef1c: th\u01b0\u01a1ng m\u1ea1i \u0111i\u1ec7n t\u1eed, ng\u00e2n h\u00e0ng \u0111i\u1ec7n t\u1eed, giao ti\u1ebfp tr\u1ef1c tuy\u1ebfn,… Ngo\u00e0i ra, RSA c\u0169ng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong m\u1ed9t s\u1ed1 \u1ee9ng d\u1ee5ng phi m\u1eadt m\u00e3 nh\u01b0: x\u00e1c th\u1ef1c danh t\u00ednh v\u00e0 qu\u1ea3n l\u00fd b\u1ea3n quy\u1ec1n.<\/p>\n\n\n\n

1.3 Ph\u00e2n bi\u1ec7t ch\u1eef k\u00fd s\u1ed1 v\u00e0 ch\u1eef k\u00fd \u0111i\u1ec7n t\u1eed<\/strong><\/h3>\n\n\n\n

Ch\u1eef k\u00fd \u0111i\u1ec7n t\u1eed<\/a> (electronic signature)<\/strong> l\u00e0 m\u1ed9t d\u1ea1ng ch\u1eef k\u00fd \u0111\u01b0\u1ee3c t\u1ea1o ra d\u01b0\u1edbi d\u1ea1ng t\u1eeb, ch\u1eef, s\u1ed1, k\u00fd hi\u1ec7u, \u00e2m thanh, h\u00ecnh \u1ea3nh, ho\u1eb7c c\u00e1c h\u00ecnh th\u1ee9c kh\u00e1c b\u1eb1ng ph\u01b0\u01a1ng ti\u1ec7n \u0111i\u1ec7n t\u1eed. N\u00f3 g\u1eafn li\u1ec1n ho\u1eb7c k\u1ebft h\u1ee3p m\u1ed9t c\u00e1ch logic v\u1edbi th\u00f4ng \u0111i\u1ec7p d\u1eef li\u1ec7u \u0111\u1ec3 ng\u01b0\u1eddi ph\u00ea duy\u1ec7t c\u00f3 th\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c ng\u01b0\u1eddi ch\u1ee7 c\u1ee7a d\u1eef li\u1ec7u tr\u00ean c\u00e1c v\u0103n b\u1ea3n \u0111i\u1ec7n t\u1eed.<\/p>\n\n\n

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\"Ch\u1eef<\/figure><\/div>\n\n\n

Ch\u1eef k\u00fd s\u1ed1 (digital signature) <\/strong>l\u00e0 m\u1ed9t d\u1ea1ng ch\u1eef k\u00fd \u0111i\u1ec7n t\u1eed \u0111\u01b0\u1ee3c t\u1ea1o ra th\u00f4ng qua s\u1ef1 bi\u1ebfn \u0111\u1ed5i th\u00f4ng \u0111i\u1ec7p d\u1eef li\u1ec7u b\u1eb1ng h\u1ec7 th\u1ed1ng m\u1eadt m\u00e3 kh\u00f4ng \u0111\u1ed1i x\u1ee9ng. V\u1edbi ch\u1eef k\u00fd s\u1ed1, ng\u01b0\u1eddi nh\u1eadn c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng th\u00f4ng \u0111i\u1ec7p d\u1eef li\u1ec7u ban \u0111\u1ea7u v\u00e0 kh\u00f3a c\u00f4ng khai c\u1ee7a ng\u01b0\u1eddi k\u00fd \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh ch\u00ednh x\u00e1c ngu\u1ed3n g\u1ed1c v\u00e0 \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a th\u00f4ng \u0111i\u1ec7p d\u1eef li\u1ec7u.<\/p>\n\n\n\n

Nh\u01b0 v\u1eady, ch\u1eef k\u00fd s\u1ed1 l\u00e0 m\u1ed9t t\u1eadp h\u1ee3p con c\u1ee7a ch\u1eef k\u00fd \u0111i\u1ec7n t\u1eed, \u0111\u01b0\u1ee3c x\u00e1c th\u1ef1c th\u00f4ng qua b\u00ean th\u1ee9 ba l\u00e0 c\u00e1c t\u1ed5 ch\u1ee9c cung c\u1ea5p d\u1ecbch v\u1ee5 ch\u1ee9ng th\u1ef1c ch\u1eef k\u00fd s\u1ed1 (CA).<\/strong><\/p>\n\n\n\n

C\u1ea3 hai lo\u1ea1i ch\u1eef k\u00fd n\u00e0y \u0111\u1ec1u h\u1ed7 tr\u1ee3 cho ho\u1ea1t \u0111\u1ed9ng c\u1ee7a doanh nghi\u1ec7p. Tuy nhi\u00ean, khi s\u1eed d\u1ee5ng ch\u1eef k\u00fd \u0111i\u1ec7n t\u1eed kh\u00f4ng c\u00f3 s\u1ef1 x\u00e1c th\u1ef1c c\u1ee7a CA, doanh nghi\u1ec7p c\u1ea7n c\u00e2n nh\u1eafc c\u00e1c r\u1ee7i ro c\u00f3 th\u1ec3 ph\u00e1t sinh:<\/p>\n\n\n\n