{"id":338111,"date":"2024-05-04T18:59:25","date_gmt":"2024-05-04T11:59:25","guid":{"rendered":"https:\/\/hoanghamobile.com\/tin-tuc\/?p=338111"},"modified":"2024-05-04T18:59:25","modified_gmt":"2024-05-04T11:59:25","slug":"captcha","status":"publish","type":"post","link":"https:\/\/hoanghamobile.com\/tin-tuc\/captcha\/","title":{"rendered":"M\u00e3 CAPTCHA l\u00e0 g\u00ec? Vai tr\u00f2 c\u1ee7a trong b\u1ea3o m\u1eadt tr\u1ef1c tuy\u1ebfn"},"content":{"rendered":"

Khi b\u1ea1n \u0111\u0103ng k\u00fd t\u00e0i kho\u1ea3n m\u1edbi tr\u00ean website, th\u01b0\u1eddng s\u1ebd c\u00f3 y\u00eau c\u1ea7u nh\u1eadp m\u1ed9t \u0111o\u1ea1n m\u00e3 kh\u00f3 \u0111\u1ecdc. \u0110\u00f3 ch\u00ednh l\u00e0 m\u00e3 CAPTCHA. Ng\u00e0y nay, m\u00e3 n\u00e0y c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c t\u00ecm th\u1ea5y v\u1edbi c\u00e1c bi\u1ec3u m\u1eabu kh\u00e1c nhau. B\u1ea1n \u0111\u00e3 hi\u1ec3u r\u00f5 v\u1ec1 m\u00e3 n\u00e0y ch\u01b0a? M\u1ee5c \u0111\u00edch c\u1ee7a n\u00f3 l\u00e0 g\u00ec? H\u00e3y c\u00f9ng kh\u00e1m ph\u00e1 th\u00eam chi ti\u1ebft trong b\u00e0i vi\u1ebft sau.<\/strong><\/p>\n

M\u00e3 CAPTCHA l\u00e0 g\u00ec?<\/h2>\n

M\u00e3 CAPTCHA c\u00f2n \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 “Completely Automated Public Turing test to tell Computers and Humans Apart”. M\u00e3 \u0111\u00f3ng vai tr\u00f2 x\u00e1c \u0111\u1ecbnh s\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa con ng\u01b0\u1eddi v\u00e0 m\u00e1y t\u00ednh tr\u00ean internet. \u0110\u00e2y l\u00e0 m\u1ed9t h\u1ec7 th\u1ed1ng ki\u1ec3m tra \u0111\u1ec3 ph\u00e2n bi\u1ec7t ng\u01b0\u1eddi d\u00f9ng th\u1eadt v\u00e0 ng\u01b0\u1eddi d\u00f9ng t\u1ef1 \u0111\u1ed9ng. M\u1ee5c ti\u00eau ch\u00ednh l\u00e0 ng\u0103n ch\u1eb7n c\u00e1c ho\u1ea1t \u0111\u1ed9ng t\u1ef1 \u0111\u1ed9ng. Th\u00f4ng qua x\u00e1c nh\u1eadn, c\u00e1c h\u00e0nh vi spam, \u0111\u0103ng k\u00fd t\u00e0i kho\u1ea3n gi\u1ea3 m\u1ea1o ho\u1eb7c c\u00e1c h\u00e0nh vi kh\u00e1c c\u00f3 th\u1ec3 g\u00e2y h\u1ea1i cho c\u00e1c trang web s\u1ebd b\u1ecb ch\u1eb7n.<\/p>\n

M\u00e3 th\u01b0\u1eddng \u0111\u01b0\u1ee3c tr\u00ecnh b\u00e0y d\u01b0\u1edbi d\u1ea1ng h\u00ecnh \u1ea3nh ho\u1eb7c v\u0103n b\u1ea3n. M\u00e3 \u0111\u1eb7t ra c\u00e1c th\u1eed th\u00e1ch m\u00e0 m\u00e1y t\u00ednh g\u1eb7p kh\u00f3 kh\u0103n trong vi\u1ec7c nh\u1eadn d\u1ea1ng. Trong khi \u0111\u00f3, con ng\u01b0\u1eddi c\u00f3 th\u1ec3 gi\u1ea3i quy\u1ebft m\u1ed9t c\u00e1ch d\u1ec5 d\u00e0ng. V\u00ed d\u1ee5, m\u00e3 b\u1ea3o m\u1eadt c\u00f3 th\u1ec3 y\u00eau c\u1ea7u nh\u1eadp c\u00e1c k\u00fd t\u1ef1 hi\u1ec3n th\u1ecb trong m\u1ed9t h\u00ecnh \u1ea3nh. Ho\u1eb7c \u0111\u01a1n gi\u1ea3n h\u1ec7 th\u1ed1ng ch\u1ec9 y\u00eau c\u1ea7u tr\u1ea3 l\u1eddi m\u1ed9t c\u00e2u h\u1ecfi \u0111\u01a1n gi\u1ea3n.<\/p>\n

\"captcha-1\"
CAPTCHA \u0111\u00f3ng vai tr\u00f2 x\u00e1c \u0111\u1ecbnh s\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa con ng\u01b0\u1eddi v\u00e0 m\u00e1y t\u00ednh tr\u00ean internet<\/figcaption><\/figure>\n

B\u1eb1ng c\u00e1ch n\u00e0y, CAPTCHA \u0111\u00f3ng vai tr\u00f2 b\u1ea3o v\u1ec7 website kh\u1ecfi c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng t\u1ef1 \u0111\u1ed9ng. H\u00ecnh th\u1ee9c n\u00e0y \u0111\u1ea3m b\u1ea3o r\u1eb1ng ch\u1ec9 c\u00f3 con ng\u01b0\u1eddi m\u1edbi c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n y\u00eau c\u1ea7u. \u0110i\u1ec1u n\u00e0y gi\u00fap b\u1ea3o v\u1ec7 ng\u01b0\u1eddi d\u00f9ng v\u00e0 web tr\u01b0\u1edbc c\u00e1c h\u00e0nh vi gian l\u1eadn ho\u1eb7c \u0111\u1ed9c h\u1ea1i. Tuy nhi\u00ean, c\u0169ng c\u1ea7n nh\u1eadn th\u1ee9c r\u1eb1ng m\u00e3 c\u00f3 th\u1ec3 g\u00e2y kh\u00f3 ch\u1ecbu cho ng\u01b0\u1eddi d\u00f9ng. M\u00e3 c\u00e0ng ph\u1ee9c t\u1ea1p, ch\u00fang c\u00e0ng m\u1ea5t th\u1eddi gian \u0111\u1ec3 x\u00e1c th\u1ef1c. Do \u0111\u00f3, ng\u01b0\u1eddi d\u00f9ng s\u1ebd b\u1ecb c\u1ea3n tr\u1edf \u00edt nhi\u1ec1u khi v\u00e0o web.<\/p>\n

T\u1ea7m quan tr\u1ecdng c\u1ee7a m\u00e3 CAPTCHA \u0111\u1ed1i v\u1edbi an ninh m\u1ea1ng<\/h2>\n

M\u00e3 CAPTCHA \u0111\u00f3ng vai tr\u00f2 then ch\u1ed1t trong vi\u1ec7c b\u1ea3o m\u1eadt tr\u1ef1c tuy\u1ebfn. N\u00f3 ng\u0103n ch\u1eb7n c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng t\u1ef1 \u0111\u1ed9ng nh\u01b0 t\u1ea5n c\u00f4ng brute force, x\u00e2m nh\u1eadp m\u1eadt kh\u1ea9u. H\u00e3y c\u0169ng kh\u00e1m ph\u00e1 t\u1ea7m quan tr\u1ecdng c\u1ee7a m\u00e3 n\u00e0y \u0111\u1ed1i v\u1edbi an ninh m\u1ea1ng nh\u00e9.<\/p>\n

\u0110\u1ea3m b\u1ea3o an to\u00e0n cho quy tr\u00ecnh t\u1ea1o t\u00e0i kho\u1ea3n v\u00e0 truy c\u1eadp<\/h3>\n

Nh\u1edd v\u00e0o m\u00e3 CAPTCHA, an ninh cho ng\u01b0\u1eddi d\u00f9ng \u0111\u01b0\u1ee3c t\u0103ng c\u01b0\u1eddng, gi\u00fap b\u1ea3o v\u1ec7 h\u1ec7 th\u1ed1ng tr\u01b0\u1edbc c\u00e1c h\u00e0nh vi gian l\u1eadn ho\u1eb7c \u0111\u1ed9c h\u1ea1i, \u0111\u1ed3ng th\u1eddi t\u1ea1o ra m\u1ed9t m\u00f4i tr\u01b0\u1eddng tr\u1ef1c tuy\u1ebfn an to\u00e0n v\u00e0 b\u1ea3o m\u1eadt h\u01a1n cho ng\u01b0\u1eddi d\u00f9ng. M\u00e3 ki\u1ec3m tra Turing ho\u00e0n to\u00e0n t\u1ef1 \u0111\u1ed9ng \u0111\u1ec3 ph\u00e2n bi\u1ec7t m\u00e1y t\u00ednh v\u00e0 con ng\u01b0\u1eddi.<\/p>\n

M\u00e3 n\u00e0y c\u1ef1c k\u1ef3 quan tr\u1ecdng trong vi\u1ec7c b\u1ea3o v\u1ec7 qu\u00e1 tr\u00ecnh \u0111\u0103ng k\u00fd v\u00e0 \u0111\u0103ng nh\u1eadp tr\u1ef1c tuy\u1ebfn. N\u00f3 \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf nh\u1eb1m m\u1ee5c \u0111\u00edch ng\u0103n ch\u1eb7n c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng t\u1ef1 \u0111\u1ed9ng nh\u01b0 brute-force. \u0110\u00e2y l\u00e0 n\u01a1i m\u00e0 m\u00e1y t\u00ednh th\u1eed t\u1ea5t c\u1ea3 c\u00e1c kh\u1ea3 n\u0103ng, ho\u1eb7c t\u1ea5n c\u00f4ng t\u1eeb \u0111i\u1ec3n, n\u01a1i m\u00e0 m\u00e1y t\u00ednh th\u1eed t\u1ea5t c\u1ea3 c\u00e1c t\u1eeb trong m\u1ed9t danh s\u00e1ch c\u1ed1 \u0111\u1ecbnh.<\/p>\n

\"CAPTCHA-2\"
M\u00e3 b\u1ea3o v\u1ec7 qu\u00e1 tr\u00ecnh \u0111\u0103ng k\u00fd v\u00e0 \u0111\u0103ng nh\u1eadp tr\u1ef1c tuy\u1ebfn c\u1ee7a ng\u01b0\u1eddi d\u00f9ng<\/figcaption><\/figure>\n

\u0110i\u1ec3m \u0111\u1eb7c bi\u1ec7t c\u1ee7a m\u00e3 l\u00e0 y\u00eau c\u1ea7u nh\u1eadp th\u00f4ng tin x\u00e1c nh\u1eadn m\u1ed9t c\u00e1ch th\u1ee7 c\u00f4ng. \u0110i\u1ec1u n\u00e0y t\u1ea1o ra m\u1ed9t r\u00e0o c\u1ea3n cho c\u00e1c ph\u1ea7n m\u1ec1m t\u1ef1 \u0111\u1ed9ng. R\u00e0o c\u1ea3n n\u00e0y \u0111\u1ea3m b\u1ea3o r\u1eb1ng ch\u1ec9 con ng\u01b0\u1eddi m\u1edbi c\u00f3 kh\u1ea3 n\u0103ng hi\u1ec3u \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u. T\u1eeb \u0111\u00f3 h\u1ecd m\u1edbi truy c\u1eadp v\u00e0o c\u00e1c t\u00e0i kho\u1ea3n \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7. Nh\u1edd v\u00e0o m\u00e3 CAPTCHA, an ninh cho ng\u01b0\u1eddi d\u00f9ng \u0111\u01b0\u1ee3c t\u0103ng c\u01b0\u1eddng \u0111\u00e1ng k\u1ec3. H\u1ec7 th\u1ed1ng \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7 tr\u01b0\u1edbc c\u00e1c h\u00e0nh vi gian l\u1eadn ho\u1eb7c \u0111\u1ed9c h\u1ea1i. \u0110\u1ed3ng th\u1eddi, m\u00e3 c\u0169ng t\u1ea1o ra m\u1ed9t m\u00f4i tr\u01b0\u1eddng tr\u1ef1c tuy\u1ebfn an to\u00e0n v\u00e0 b\u1ea3o m\u1eadt, gi\u00fap h\u1ecd y\u00ean t\u00e2m h\u01a1n khi th\u1ef1c hi\u1ec7n c\u00e1c ho\u1ea1t \u0111\u1ed9ng tr\u1ef1c tuy\u1ebfn.<\/p>\n

Ch\u1eb7n spam<\/h3>\n

M\u00e3 CAPTCHA \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c ng\u0103n ch\u1eb7n spam tr\u00ean internet. H\u00ecnh th\u1ee9c n\u00e0y \u0111\u1ea3m b\u1ea3o r\u1eb1ng n\u1ea1n spam web, di\u1ec5n \u0111\u00e0n v\u00e0 mail b\u1ecb gi\u1ea3m thi\u1ec3u \u0111\u00e1ng k\u1ec3. \u0110\u1ed1i v\u1edbi nh\u1eefng ng\u01b0\u1eddi s\u1eed d\u1ee5ng, vi\u1ec7c ph\u1ea3i x\u00e1c nh\u1eadn m\u00ecnh kh\u00f4ng ph\u1ea3i l\u00e0 ch\u01b0\u01a1ng tr\u00ecnh m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng th\u00f4ng qua m\u00e3 l\u00e0 m\u1ed9t b\u01b0\u1edbc quan tr\u1ecdng. H\u1ec7 th\u1ed1ng s\u1ebd qua \u0111\u00f3 x\u00e1c nh\u1eadn, ch\u1eb7n g\u1eedi tin nh\u1eafn spam ho\u1eb7c t\u1ea1o ra c\u00e1c t\u00e0i kho\u1ea3n gi\u1ea3 m\u1ea1o.<\/p>\n

M\u00e3 t\u1ea1o ra m\u1ed9t th\u1eed th\u00e1ch kh\u00f3 kh\u0103n cho c\u00e1c bot v\u00e0 ph\u1ea7n m\u1ec1m t\u1ef1 \u0111\u1ed9ng. Qua \u0111\u00f3, bot s\u1ebd kh\u00f4ng th\u1ec3 g\u1eedi tin nh\u1eafn spam ho\u1eb7c \u0111\u0103ng k\u00fd gi\u1ea3 m\u1ea1o h\u00e0ng lo\u1ea1t. Vi\u1ec7c n\u00e0y kh\u00f4ng ch\u1ec9 gi\u00fap c\u1ea3i thi\u1ec7n tr\u1ea3i nghi\u1ec7m ng\u01b0\u1eddi d\u00f9ng b\u1eb1ng c\u00e1ch l\u00e0m s\u1ea1ch kh\u00f4ng gian tr\u1ef1c tuy\u1ebfn kh\u1ecfi nhi\u1ec5u lo\u1ea1n. N\u00f3 c\u00f2n gi\u1eef cho th\u00f4ng tin c\u00e1 nh\u00e2n v\u00e0 d\u1eef li\u1ec7u tr\u1ef1c tuy\u1ebfn an to\u00e0n.<\/p>\n

\"CAPTCHA-3\"
M\u00e3 t\u1ea1o ra m\u1ed9t th\u1eed th\u00e1ch kh\u00f3 kh\u0103n m\u00e0 bot s\u1ebd kh\u00f4ng th\u1ec3 g\u1eedi tin nh\u1eafn spam ho\u1eb7c \u0111\u0103ng k\u00fd gi\u1ea3 m\u1ea1o h\u00e0ng lo\u1ea1t<\/figcaption><\/figure>\n

M\u00e3 CAPTCHA c\u00f2n cung c\u1ea5p m\u1ed9t l\u1edbp b\u1ea3o v\u1ec7 b\u1ed5 sung. Vi\u1ec7c t\u0103ng c\u01b0\u1eddng l\u1edbp b\u1ea3o v\u1ec7 \u0111\u1eb7c bi\u1ec7t quan tr\u1ecdng trong m\u00f4i tr\u01b0\u1eddng tr\u1ef1c tuy\u1ebfn n\u01a1i m\u00e0 spam c\u00f3 th\u1ec3 l\u00e0m gi\u1ea3m hi\u1ec7u su\u1ea5t v\u00e0 \u0111\u00e1ng k\u1ec3 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn s\u1ef1 tin c\u1eady c\u1ee7a c\u00e1c n\u1ec1n t\u1ea3ng tr\u1ef1c tuy\u1ebfn. C\u1ed9ng \u0111\u1ed3ng tr\u1ef1c tuy\u1ebfn c\u00f3 th\u1ec3 an t\u00e2m \u0111\u1ec3 chia s\u1ebb th\u00f4ng tin. H\u1ecd kh\u00f4ng c\u00f2n lo ng\u1ea1i v\u1ec1 r\u1ee7i ro t\u1eeb spam v\u00e0 c\u00e1c ho\u1ea1t \u0111\u1ed9ng gian l\u1eadn kh\u00e1c.<\/p>\n

Ph\u00f2ng tr\u00e1nh t\u1ea5n c\u00f4ng DDoS<\/h3>\n

DoS (Distributed Denial of Service) l\u00e0 lo\u1ea1i t\u1ea5n c\u00f4ng t\u1eeb bot t\u1ef1 \u0111\u1ed9ng. V\u1edbi h\u00ecnh th\u1ee9c n\u00e0y, h\u00e0ng lo\u1ea1t m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng g\u1eedi m\u1ed9t l\u01b0\u1ee3ng l\u1edbn y\u00eau c\u1ea7u \u0111\u1ebfn m\u1ed9t h\u1ec7 th\u1ed1ng tr\u1ef1c tuy\u1ebfn. M\u1ee5c ti\u00eau c\u1ee7a cu\u1ed9c t\u1ea5n c\u00f4ng l\u00e0 l\u00e0m cho h\u1ec7 th\u1ed1ng n\u00e0y kh\u00f4ng th\u1ec3 x\u1eed l\u00fd \u0111\u1ee7 s\u1ed1 l\u01b0\u1ee3ng l\u1edbn c\u00e1c y\u00eau c\u1ea7u. T\u1eeb \u0111\u00f3, n\u00f3 d\u1eabn \u0111\u1ebfn vi\u1ec7c t\u1eeb ch\u1ed1i d\u1ecbch v\u1ee5 cho ng\u01b0\u1eddi d\u00f9ng h\u1ee3p l\u1ec7.<\/p>\n

M\u00e3 CAPTCHA c\u00f3 th\u1ec3 \u0111\u1ed1i ph\u00f3 v\u1edbi c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng DDoS.\u00a0\u0110\u00e2y l\u00e0 m\u1ed9t bi\u1ec7n ph\u00e1p b\u1ed5 sung \u0111\u1ec3 ki\u1ec3m so\u00e1t y\u00eau c\u1ea7u t\u1eeb ng\u01b0\u1eddi d\u00f9ng. M\u1ed7i y\u00eau c\u1ea7u ph\u1ea3i tr\u1ea3i qua m\u1ed9t b\u01b0\u1edbc x\u00e1c minh. Trong \u0111\u00f3 ng\u01b0\u1eddi d\u00f9ng ph\u1ea3i nh\u1eadp m\u1ed9t chu\u1ed7i k\u00fd t\u1ef1 ho\u1eb7c th\u1ef1c hi\u1ec7n m\u1ed9t nhi\u1ec7m v\u1ee5 nh\u1ea5t \u0111\u1ecbnh m\u00e0 m\u00e1y t\u00ednh g\u1eb7p kh\u00f3 kh\u0103n khi th\u1ef1c hi\u1ec7n. \u0110i\u1ec1u n\u00e0y t\u1ea1o ra m\u1ed9t r\u00e0o c\u1ea3n m\u00e0 c\u00e1c bot t\u1ef1 \u0111\u1ed9ng g\u1eb7p kh\u00f3 kh\u0103n trong vi\u1ec7c v\u01b0\u1ee3t qua.<\/p>\n

\"CAPTCHA-4\"
DoS (Distributed Denial of Service) l\u00e0 lo\u1ea1i t\u1ea5n c\u00f4ng t\u1eeb bot t\u1ef1 \u0111\u1ed9ng<\/figcaption><\/figure>\n

B\u1eb1ng c\u00e1ch n\u00e0y, vi\u1ec7c s\u1eed d\u1ee5ng m\u00e3 kh\u00f4ng ch\u1ec9 gi\u00fap l\u00e0m ch\u1eadm l\u1ea1i qu\u00e1 tr\u00ecnh t\u1ea5n c\u00f4ng DDoS. H\u01a1n th\u1ebf n\u1eefa, m\u00e3 c\u00f2n c\u00f3 th\u1ec3 ng\u0103n ch\u1eb7n ho\u1eb7c gi\u1ea3m thi\u1ec3u t\u00e1c \u0111\u1ed9ng c\u1ee7a ch\u00fang. Do bot t\u1ef1 \u0111\u1ed9ng kh\u00f4ng th\u1ec3 ho\u00e0n th\u00e0nh b\u01b0\u1edbc x\u00e1c minh, h\u1ec7 th\u1ed1ng c\u00f3 th\u1ec3 nh\u1eadn bi\u1ebft v\u00e0 t\u1eeb ch\u1ed1i y\u00eau c\u1ea7u t\u1eeb c\u00e1c ngu\u1ed3n kh\u00f4ng mong mu\u1ed1n.<\/p>\n

Ch\u1ed1ng l\u1ea1i vi\u1ec7c gi\u1ea3 m\u1ea1o tr\u1ef1c tuy\u1ebfn<\/h3>\n

M\u00e3 CAPTCHA kh\u00f4ng ch\u1ec9 ng\u0103n ch\u1eb7n c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng DDoS. Thay v\u00ec y\u00eau c\u1ea7u ng\u01b0\u1eddi d\u00f9ng ch\u1ec9 \u0111\u01a1n gi\u1ea3n l\u00e0 nh\u1eadp th\u00f4ng tin c\u01a1 b\u1ea3n, h\u1ecd ph\u1ea3i ho\u00e0n th\u00e0nh m\u1ed9t th\u1eed th\u00e1ch nh\u1ecf \u0111\u1ec3 x\u00e1c minh danh t\u00ednh c\u1ee7a m\u00ecnh. Qu\u00e1 tr\u00ecnh n\u00e0y gi\u00fap lo\u1ea1i b\u1ecf ho\u1eb7c l\u00e0m kh\u00f3 kh\u0103n h\u01a1n vi\u1ec7c t\u1ea1o ra c\u00e1c t\u00e0i kho\u1ea3n gi\u1ea3 m\u1ea1o. Nh\u1eefng t\u00e0i kho\u1ea3n n\u00e0y th\u01b0\u1eddng \u0111\u01b0\u1ee3c t\u1ea1o b\u1eb1ng c\u00e1c ch\u01b0\u01a1ng tr\u00ecnh m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng.<\/p>\n

\"CAPTCHA-5\"
M\u00e3 c\u00f2n ch\u1ed1ng l\u1ea1i s\u1ef1 gi\u1ea3 m\u1ea1o c\u00e1c t\u00e0i kho\u1ea3n tr\u1ef1c tuy\u1ebfn<\/figcaption><\/figure>\n

B\u1eb1ng c\u00e1ch t\u1ea1o ra m\u1ed9t b\u01b0\u1edbc x\u00e1c minh b\u1ed5 sung, m\u00e3 l\u00e0m cho qu\u00e1 tr\u00ecnh t\u1ea1o t\u00e0i kho\u1ea3n \u0111\u1ed1i v\u1edbi c\u00e1c bot t\u1ef1 \u0111\u1ed9ng tr\u1edf n\u00ean ph\u1ee9c t\u1ea1p h\u01a1n. K\u1ebft qu\u1ea3 l\u00e0, t\u1ef7 l\u1ec7 t\u1ea1o t\u00e0i kho\u1ea3n gi\u1ea3 m\u1ea1o b\u1ecb th\u1ea5t b\u1ea1i nhi\u1ec1u h\u01a1n. Ng\u01b0\u1eddi d\u00f9ng th\u1ef1c s\u1ef1 c\u00f3 th\u1ec3 ho\u00e0n th\u00e0nh c\u00e1c th\u1eed th\u00e1ch n\u00e0y m\u1ed9t c\u00e1ch d\u1ec5 d\u00e0ng. Trong khi \u0111\u00f3, c\u00e1c ch\u01b0\u01a1ng tr\u00ecnh m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng th\u01b0\u1eddng g\u1eb7p kh\u00f3 kh\u0103n ho\u1eb7c th\u1eadm ch\u00ed kh\u00f4ng th\u1ec3 ho\u00e0n th\u00e0nh \u0111\u01b0\u1ee3c.<\/p>\n

\u0110i\u1ec1u n\u00e0y gi\u00fap b\u1ea3o v\u1ec7 t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a c\u1ed9ng \u0111\u1ed3ng tr\u1ef1c tuy\u1ebfn. Qua s\u1eed d\u1ee5ng m\u00e3, h\u1ec7 th\u1ed1ng \u0111\u1ea3m b\u1ea3o r\u1eb1ng ch\u1ec9 nh\u1eefng ng\u01b0\u1eddi th\u1ef1c s\u1ef1 c\u00f3 \u00fd \u0111\u1ecbnh t\u1ea1o t\u00e0i kho\u1ea3n m\u1edbi s\u1ebd c\u00f3 th\u1ec3 l\u00e0m \u0111\u01b0\u1ee3c.<\/p>\n

C\u00e1c h\u00ecnh th\u1ee9c b\u1ea3o m\u1eadt c\u1ee7a CAPTCHA<\/h2>\n

CAPTCHA \u0111\u00e3 tr\u1ea3i qua m\u1ed9t lo\u1ea1t c\u00e1c phi\u00ean b\u1ea3n v\u00e0 bi\u1ebfn th\u1ec3. S\u1ef1 thay \u0111\u1ed5i n\u00e0y nh\u1eb1m \u0111\u00e1p \u1ee9ng nhu c\u1ea7u b\u1ea3o m\u1eadt tr\u1ef1c tuy\u1ebfn ng\u00e0y c\u00e0ng cao v\u00e0 \u0111\u1ed1i ph\u00f3 v\u1edbi c\u00e1c k\u1ef9 thu\u1eadt t\u1ea5n c\u00f4ng ng\u00e0y c\u00e0ng ph\u1ee9c t\u1ea1p t\u1eeb ph\u00eda m\u00e1y t\u00ednh. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 phi\u00ean b\u1ea3n c\u1ee7a ph\u1ed5 bi\u1ebfn.<\/p>\n

CAPTCHA v\u0103n b\u1ea3n<\/h3>\n

CAPTCHA d\u1ea1ng v\u0103n b\u1ea3n, c\u00f2n \u0111\u01b0\u1ee3c bi\u1ebft \u0111\u1ebfn nh\u01b0 x\u00e1c th\u1ef1c d\u1ea1ng ch\u1eef. V\u1edbi h\u00ecnh th\u1ee9c n\u00e0y, ng\u01b0\u1eddi d\u00f9ng \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u nh\u1eadp l\u1ea1i m\u1ed9t \u0111o\u1ea1n v\u0103n b\u1ea3n ho\u1eb7c m\u1ed9t chu\u1ed7i k\u00fd t\u1ef1 \u0111\u01b0\u1ee3c hi\u1ec3n th\u1ecb trong m\u1ed9t h\u00ecnh \u1ea3nh. Th\u01b0\u1eddng th\u00ec m\u00e3 bao g\u1ed3m m\u1ed9t chu\u1ed7i c\u00e1c k\u00fd t\u1ef1 ch\u1eef c\u00e1i v\u00e0 s\u1ed1 \u0111\u01b0\u1ee3c hi\u1ec3n th\u1ecb trong m\u1ed9t h\u00ecnh \u1ea3nh m\u1edd ho\u1eb7c nhi\u1ec5u. \u0110\u00f4i khi, c\u00e1c bi\u1ebfn th\u1ec3 c\u1ee7a c\u00f3 th\u1ec3 bao g\u1ed3m c\u00e1c ch\u1eef c\u00e1i \u0111\u01b0\u1ee3c bi\u1ebfn \u0111\u1ed5i m\u1ed9t ch\u00fat. M\u1ee5c \u0111\u00edch l\u00e0 l\u00e0m kh\u00f3 cho vi\u1ec7c nh\u1eadn d\u1ea1ng b\u1eb1ng c\u00e1c thu\u1eadt to\u00e1n nh\u1eadn d\u1ea1ng k\u00fd t\u1ef1.<\/p>\n

\"CAPTCHA-6\"
CAPTCHA v\u0103n b\u1ea3n<\/figcaption><\/figure>\n

Vi\u1ec7c s\u1eed d\u1ee5ng m\u00e3 d\u1ea1ng v\u0103n b\u1ea3n gi\u00fap \u0111\u1ea3m b\u1ea3o r\u1eb1ng ng\u01b0\u1eddi d\u00f9ng t\u01b0\u01a1ng t\u00e1c v\u1edbi website l\u00e0 con ng\u01b0\u1eddi th\u1eadt s\u1ef1. T\u1eeb \u0111\u00f3 n\u00f3 gi\u00fap gi\u1ea3m thi\u1ec3u r\u1ee7i ro an ninh m\u1ea1ng v\u00e0 t\u0103ng c\u01b0\u1eddng b\u1ea3o m\u1eadt cho website. H\u00ecnh th\u1ee9c n\u00e0y h\u1eefu \u00edch trong vi\u1ec7c ng\u0103n ch\u1eb7n c\u00e1c h\u00e0nh \u0111\u1ed9ng tr\u00e1i ph\u00e9p. Tuy nhi\u00ean, \u0111\u00f4i khi n\u00f3 c\u0169ng c\u00f3 th\u1ec3 l\u00e0m phi\u1ec1n ng\u01b0\u1eddi d\u00f9ng b\u1edfi v\u00ec \u0111\u00f4i khi h\u00ecnh \u1ea3nh c\u00f3 th\u1ec3 kh\u00f3 nh\u1eadn d\u1ea1ng, \u0111\u1eb7c bi\u1ec7t l\u00e0 \u0111\u1ed1i v\u1edbi nh\u1eefng ng\u01b0\u1eddi c\u00f3 kh\u1ea3 n\u0103ng nh\u00ecn y\u1ebfu ho\u1eb7c khi h\u00ecnh \u1ea3nh b\u1ecb nhi\u1ec5u nhi\u1ec1u. \u0110i\u1ec1u n\u00e0y \u0111\u00e3 th\u00fac \u0111\u1ea9y s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00e1c h\u00ecnh th\u1ee9c x\u00e1c nh\u1eadn ti\u00ean ti\u1ebfn kh\u00e1c.<\/p>\n

CAPTCHA h\u00ecnh \u1ea3nh<\/h3>\n

\u0110\u00e2y l\u00e0 m\u1ed9t lo\u1ea1i ki\u1ec3m tra x\u00e1c th\u1ef1c s\u1eed d\u1ee5ng h\u00ecnh \u1ea3nh. Thay v\u00ec y\u00eau c\u1ea7u ng\u01b0\u1eddi d\u00f9ng nh\u1eadp c\u00e1c k\u00fd t\u1ef1 t\u1eeb m\u1ed9t h\u00ecnh \u1ea3nh ho\u1eb7c m\u1ed9t chu\u1ed7i k\u00fd t\u1ef1 ng\u1eabu nhi\u00ean, h\u1ec7 th\u1ed1ng y\u00eau c\u1ea7u ng\u01b0\u1eddi d\u00f9ng x\u00e1c minh b\u1eb1ng c\u00e1ch nh\u00ecn v\u00e0 ch\u1ecdn c\u00e1c h\u00ecnh \u1ea3nh c\u00f3 ch\u1ee9a c\u00e1c ph\u1ea7n t\u1eed c\u1ee5 th\u1ec3. M\u00e3 h\u00ecnh \u1ea3nh th\u01b0\u1eddng bao g\u1ed3m c\u00e1c h\u00ecnh \u1ea3nh nh\u1ecf ho\u1eb7c bi\u1ec3u t\u01b0\u1ee3ng.<\/p>\n

\u0110\u00f3 c\u00f3 th\u1ec3 l\u00e0 h\u00ecnh \u1ea3nh c\u1ee7a xe bu\u00fdt, bi\u1ec3n giao th\u00f4ng, c\u00e2y c\u1ecf, \u0111\u00e8n giao th\u00f4ng, \u0111\u00e8n pha \u00f4 t\u00f4, \u0111\u00e8n \u0111\u01b0\u1eddng… Ng\u01b0\u1eddi d\u00f9ng \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u ch\u1ecdn t\u1ea5t c\u1ea3 c\u00e1c h\u00ecnh \u1ea3nh ch\u1ee9a c\u00e1c ph\u1ea7n t\u1eed \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u. Ch\u1eb3ng h\u1ea1n, h\u1ecd c\u1ea7n ch\u1ecdn “ch\u1ecdn t\u1ea5t c\u1ea3 c\u00e1c h\u00ecnh \u1ea3nh ch\u1ee9a bi\u1ec3n giao th\u00f4ng”.<\/p>\n

\"CAPTCHA-7\"
CAPTCHA h\u00ecnh \u1ea3nh<\/figcaption><\/figure>\n

Ph\u01b0\u01a1ng th\u1ee9c th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng v\u00ec ch\u00fang kh\u00e1 kh\u00f3 \u0111\u1ec3 c\u00e1c ch\u01b0\u01a1ng tr\u00ecnh m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng nh\u1eadn di\u1ec7n \u0111\u01b0\u1ee3c. \u0110i\u1ec1u n\u00e0y l\u00e0m cho vi\u1ec7c t\u1ef1 \u0111\u1ed9ng t\u1ea1o ho\u1eb7c bypass tr\u1edf n\u00ean kh\u00f3 kh\u0103n h\u01a1n. M\u00e3 h\u00ecnh \u1ea3nh c\u00f3 th\u1ec3 hi\u1ec7u qu\u1ea3 trong vi\u1ec7c ng\u0103n ch\u1eb7n c\u00e1c t\u1ea5n c\u00f4ng t\u1ef1 \u0111\u1ed9ng. Tuy nhi\u00ean, ch\u00fang c\u0169ng c\u00f3 th\u1ec3 l\u00e0m cho tr\u1ea3i nghi\u1ec7m c\u1ee7a ng\u01b0\u1eddi d\u00f9ng tr\u1edf n\u00ean phi\u1ec1n to\u00e1i. \u0110\u1eb7c bi\u1ec7t l\u00e0 h\u00ecnh nh\u1eadn di\u1ec7n c\u00e0ng ph\u1ee9c t\u1ea1p th\u00ec c\u00e0ng t\u1ed1n th\u1eddi gian. \u0110i\u1ec1u n\u00e0y \u0111\u00e3 th\u00fac \u0111\u1ea9y s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00e1c ph\u01b0\u01a1ng ph\u00e1p m\u1edbi c\u00f3 th\u1ec3 d\u1ec5 d\u00e0ng h\u01a1n cho ng\u01b0\u1eddi d\u00f9ng, nh\u01b0ng v\u1eabn \u0111\u1ee7 kh\u00f3 cho bot.<\/p>\n

CAPTCHA \u00e2m thanh<\/h3>\n

\u0110\u00e2y l\u00e0 m\u1ed9t lo\u1ea1i x\u00e1c th\u1ef1c b\u1eb1ng \u00e2m thanh. C\u1ee5 th\u1ec3, ng\u01b0\u1eddi d\u00f9ng \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u nghe v\u00e0 nh\u1eadp l\u1ea1i m\u1ed9t \u0111o\u1ea1n \u00e2m thanh ho\u1eb7c m\u1ed9t chu\u1ed7i \u00e2m thanh \u0111\u1ec3 x\u00e1c minh r\u1eb1ng h\u1ecd l\u00e0 con ng\u01b0\u1eddi, kh\u00f4ng ph\u1ea3i l\u00e0 ch\u01b0\u01a1ng tr\u00ecnh m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng. Th\u01b0\u1eddng th\u00ec m\u00e3 \u00e2m thanh bao g\u1ed3m m\u1ed9t \u0111o\u1ea1n \u00e2m thanh ng\u1eafn. \u0110o\u1ea1n n\u00e0y ch\u1ee9a m\u1ed9t chu\u1ed7i c\u00e1c k\u00fd t\u1ef1 ho\u1eb7c t\u1eeb \u0111\u01b0\u1ee3c \u0111\u1ecdc ra b\u1eb1ng gi\u1ecdng ng\u01b0\u1eddi ho\u1eb7c m\u1ed9t lo\u1ea1i \u00e2m thanh t\u1ed5ng h\u1ee3p.<\/p>\n

M\u1ee5c \u0111\u00edch c\u1ee7a h\u00ecnh th\u1ee9c n\u00e0y gi\u1ed1ng nh\u01b0 c\u00e1c lo\u1ea1i h\u00ecnh th\u1ee9c kh\u00e1c. \u0110\u00f3 l\u00e0 ng\u0103n ch\u1eb7n c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng t\u1ef1 \u0111\u1ed9ng ho\u1eb7c spam t\u1eeb c\u00e1c bot. N\u00f3 th\u1ef1c hi\u1ec7n b\u1eb1ng c\u00e1ch y\u00eau c\u1ea7u m\u1ed9t kh\u1ea3 n\u0103ng c\u1ea3m nh\u1eadn v\u00e0 x\u1eed l\u00fd \u00e2m thanh ch\u1ec9 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n b\u1edfi con ng\u01b0\u1eddi.<\/p>\n

\"CAPTCHA-8\"
M\u00e3 d\u00f9ng \u00e2m thanh x\u00e1c th\u1ef1c b\u1eb1ng c\u00e1ch b\u1eadt bi\u1ec3u t\u01b0\u1ee3ng loa<\/figcaption><\/figure>\n

M\u1eb7c d\u00f9 CAPTCHA \u00e2m thanh c\u00f3 th\u1ec3 h\u1eefu \u00edch trong vi\u1ec7c ng\u0103n ch\u1eb7n c\u00e1c h\u00e0nh \u0111\u1ed9ng tr\u00e1i ph\u00e9p. Tuy nhi\u00ean \u0111\u00f4i khi n\u00f3 c\u0169ng c\u00f3 th\u1ec3 g\u00e2y ra m\u1ed9t s\u1ed1 kh\u00f3 kh\u0103n cho ng\u01b0\u1eddi d\u00f9ng. \u0110\u1eb7c bi\u1ec7t h\u00ecnh th\u1ee9c n\u00e0y v\u00f4 hi\u1ec7u v\u1edbi nh\u1eefng ng\u01b0\u1eddi c\u00f3 v\u1ea5n \u0111\u1ec1 v\u1ec1 th\u00ednh gi\u00e1c. \u0110i\u1ec1u n\u00e0y \u0111\u00e3 th\u00fac \u0111\u1ea9y s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00e1c h\u00ecnh th\u1ee9c kh\u00e1c nh\u01b0 h\u00ecnh \u1ea3nh v\u00e0 c\u00e1c gi\u1ea3i ph\u00e1p x\u00e1c minh kh\u00f4ng g\u00e2y phi\u1ec1n to\u00e1i h\u01a1n.<\/p>\n

ReCAPTCHA<\/h3>\n

ReCAPTCHA l\u00e0 d\u1ecbch v\u1ee5\u00a0x\u00e1c minh ng\u01b0\u1eddi d\u00f9ng \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi Google. D\u1ecbch v\u1ee5 n\u00e0y \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u00ednh an to\u00e0n v\u00e0 b\u1ea3o m\u1eadt c\u1ee7a c\u00e1c trang web. M\u1ee5c \u0111\u00edch ch\u00ednh c\u1ee7a m\u00e3 l\u00e0 x\u00e1c \u0111\u1ecbnh xem ng\u01b0\u1eddi d\u00f9ng l\u00e0 con ng\u01b0\u1eddi th\u1ef1c s\u1ef1 hay l\u00e0 m\u1ed9t ch\u01b0\u01a1ng tr\u00ecnh m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng (bot).<\/p>\n

H\u00ecnh th\u1ee9c CAPTCHA n\u00e0y bao g\u1ed3m hai lo\u1ea1i c\u01a1 ch\u1ebf x\u00e1c minh.<\/p>\n

ReCaptcha v2: \u0110\u00e2y l\u00e0 phi\u00ean b\u1ea3n c\u0169. H\u1ec7 th\u1ed1ng y\u00eau c\u1ea7u th\u1ef1c hi\u1ec7n m\u1ed9t th\u1eed th\u00e1ch \u0111\u01a1n gi\u1ea3n. \u0110\u00f3 c\u00f3 th\u1ec3 l\u00e0 nh\u1ea5p v\u00e0o \u00f4 vu\u00f4ng, ki\u1ec3m tra v\u00e0o m\u1ed9t \u00f4 checkbox. Ho\u1eb7c \u0111\u00f3 c\u00f3 th\u1ec3 l\u00e0 ch\u1ecdn t\u1ea5t c\u1ea3 c\u00e1c h\u00ecnh \u1ea3nh ch\u1ee9a m\u1ed9t lo\u1ea1i \u0111\u1ed1i t\u01b0\u1ee3ng nh\u1ea5t \u0111\u1ecbnh. C\u00e1c y\u00eau c\u1ea7u n\u00e0y th\u00ec th\u01b0\u1eddng c\u00e1c bot t\u1ef1 \u0111\u1ed9ng kh\u00f4ng th\u1ec3 d\u1ec5 d\u00e0ng th\u1ef1c hi\u1ec7n. M\u1ee5c ti\u00eau c\u1ee7a c\u00e1ch n\u00e0y l\u00e0 \u0111\u1ea3m b\u1ea3o r\u1eb1ng ng\u01b0\u1eddi d\u00f9ng th\u1ef1c s\u1ef1 l\u00e0 con ng\u01b0\u1eddi.<\/p>\n

ReCaptcha v3: \u0110\u00e2y l\u00e0 phi\u00ean b\u1ea3n m\u1edbi nh\u1ea5t. N\u00f3 l\u00e0 m\u1ed9t h\u1ec7 th\u1ed1ng x\u00e1c minh ng\u1ea7m t\u1ef1 \u0111\u1ed9ng h\u01a1n. Thay v\u00ec y\u00eau c\u1ea7u ng\u01b0\u1eddi d\u00f9ng th\u1ef1c hi\u1ec7n m\u1ed9t th\u1eed th\u00e1ch c\u1ee5 th\u1ec3, h\u00ecnh th\u1ee9c n\u00e0y ho\u1ea1t \u0111\u1ed9ng ng\u1ea7m b\u1eb1ng c\u00e1ch ph\u00e2n t\u00edch h\u00e0nh vi c\u1ee7a ng\u01b0\u1eddi d\u00f9ng tr\u00ean trang web. Sau \u0111\u00f3 n\u00f3 g\u00e1n cho h\u1ecd m\u1ed9t \u0111i\u1ec3m s\u1ed1 x\u00e1c minh d\u1ef1a tr\u00ean m\u1ee9c \u0111\u1ed9 \u0111\u00e1ng tin c\u1eady. C\u00e1c trang web c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng \u0111i\u1ec3m s\u1ed1 n\u00e0y \u0111\u1ec3 quy\u1ebft \u0111\u1ecbnh xem c\u00f3 n\u00ean x\u00e1c minh ng\u01b0\u1eddi d\u00f9ng ho\u1eb7c kh\u00f4ng.<\/p>\n

\"CAPTCHA-9\"
ReCAPTCHA v3<\/figcaption><\/figure>\n

H\u00ecnh th\u1ee9c n\u00e0y c\u0169ng b\u1ea3o v\u1ec7 c\u00e1c trang web kh\u1ecfi spam, t\u1ea5n c\u00f4ng brute force, ho\u1ea1t \u0111\u1ed9ng gi\u1ea3 m\u1ea1o v\u00e0 c\u00e1c lo\u1ea1i ho\u1ea1t \u0111\u1ed9ng gian l\u1eadn tr\u1ef1c tuy\u1ebfn kh\u00e1c. Ph\u01b0\u01a1ng th\u1ee9c ho\u1ea1t \u0111\u1ed9ng l\u00e0 x\u00e1c \u0111\u1ecbnh v\u00e0 ng\u0103n ch\u1eb7n bot t\u1ef1 \u0111\u1ed9ng t\u1ea5n c\u00f4ng v\u00e0o web.<\/p>\n

noCAPTCHA<\/h3>\n

NoCAPTCHA l\u00e0 m\u1ed9t h\u00ecnh th\u1ee9c ti\u00ean ti\u1ebfn c\u1ee7a vi\u1ec7c x\u00e1c th\u1ef1c CAPTCHA. \u0110i\u1ec3m \u0111\u1eb7c bi\u1ec7t c\u1ee7a h\u00ecnh th\u1ee9c n\u00e0y so v\u1edbi truy\u1ec1n th\u1ed1ng l\u00e0 n\u00f3 kh\u00f4ng y\u00eau c\u1ea7u ng\u01b0\u1eddi d\u00f9ng nh\u1eadp c\u00e1c k\u00fd t\u1ef1 ho\u1eb7c ch\u1ecdn h\u00ecnh \u1ea3nh t\u1eeb m\u1ed9t t\u1eadp h\u1ee3p cho tr\u01b0\u1edbc. Thay v\u00e0o \u0111\u00f3, h\u1ec7 th\u1ed1ng s\u1eed d\u1ee5ng m\u1ed9t h\u1ec7 th\u1ed1ng ki\u1ec3m tra \u0111\u01a1n gi\u1ea3n nh\u01b0ng hi\u1ec7u qu\u1ea3.<\/p>\n

Ng\u01b0\u1eddi d\u00f9ng ch\u1ec9 c\u1ea7n nh\u1ea5p v\u00e0o \u00f4 ki\u1ec3m tra c\u00f3 ch\u1eef \u201cT\u00f4i kh\u00f4ng ph\u1ea3i l\u00e0 robot\u201d. Tuy nhi\u00ean, \u0111\u1eb1ng sau s\u1ef1 \u0111\u01a1n gi\u1ea3n n\u00e0y l\u00e0 m\u1ed9t h\u1ec7 th\u1ed1ng ph\u00e2n t\u00edch ph\u1ee9c t\u1ea1p. Ph\u01b0\u01a1ng th\u1ee9c n\u00e0y c\u00f3 kh\u1ea3 n\u0103ng ph\u00e2n t\u00edch h\u00e0nh vi nh\u1ea5p chu\u1ed9t c\u1ee7a ng\u01b0\u1eddi d\u00f9ng. T\u1eeb \u0111\u00f3 n\u00f3 x\u00e1c \u0111\u1ecbnh li\u1ec7u h\u00e0nh \u0111\u1ed9ng \u0111\u00f3 c\u00f3 ph\u1ea3i do m\u1ed9t bot t\u1ef1 \u0111\u1ed9ng th\u1ef1c hi\u1ec7n hay kh\u00f4ng.<\/p>\n

\"CAPTCHA-10\"
NoCAPTCHA l\u00e0 h\u00ecnh th\u1ee9c ti\u00ean ti\u1ebfn nh\u1ea5t c\u1ee7a vi\u1ec7c x\u00e1c th\u1ef1c CAPTCHA<\/figcaption><\/figure>\n

C\u00f4ng ngh\u1ec7 n\u00e0y gi\u00fap ng\u0103n ch\u1eb7n c\u00e1c h\u00e0nh vi spam ho\u1eb7c l\u1ea1m d\u1ee5ng t\u1eeb c\u00e1c bot t\u1ef1 \u0111\u1ed9ng, b\u1ea3o v\u1ec7 th\u00f4ng tin v\u00e0 d\u1eef li\u1ec7u an to\u00e0n kh\u1ecfi s\u1ef1 x\u00e2m nh\u1eadp c\u1ee7a ph\u1ea7n m\u1ec1m \u0111\u1ed9c h\u1ea1i, robot v\u00e0 spam tr\u00ean website. C\u00f3 th\u1ec3 n\u00f3i \u0111\u00e2y l\u00e0 ph\u01b0\u01a1ng th\u1ee9c thu\u1eadn ti\u1ec7n v\u00e0 \u00edt t\u1ed1n th\u1eddi gian nh\u1ea5t. V\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n kh\u00f4ng ng\u1eebng c\u1ee7a c\u00f4ng ngh\u1ec7, h\u00ecnh th\u1ee9c n\u00e0y \u0111\u00e3 tr\u1edf th\u00e0nh m\u1ed9t c\u00f4ng c\u1ee5 quan tr\u1ecdng trong vi\u1ec7c b\u1ea3o v\u1ec7 ng\u01b0\u1eddi d\u00f9ng v\u00e0 h\u1ec7 th\u1ed1ng tr\u1ef1c tuy\u1ebfn kh\u1ecfi c\u00e1c m\u1ed1i \u0111e d\u1ecda ti\u1ec1m \u1ea9n.<\/p>\n

CAPTCHA ho\u1ea1t \u0111\u1ed9ng nh\u01b0 th\u1ebf n\u00e0o?<\/h2>\n

Nguy\u00ean t\u1eafc ho\u1ea1t \u0111\u1ed9ng c\u1ee7a CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) l\u00e0 s\u1eed d\u1ee5ng c\u00e1c th\u1eed th\u00e1ch m\u00e0 con ng\u01b0\u1eddi c\u00f3 th\u1ec3 gi\u1ea3i quy\u1ebft d\u1ec5 d\u00e0ng nh\u01b0ng m\u00e1y t\u00ednh g\u1eb7p kh\u00f3 kh\u0103n \u0111\u1ec3 th\u1ef1c hi\u1ec7n. M\u1ee5c \u0111\u00edch ch\u00ednh c\u1ee7a l\u00e0 ph\u00e2n bi\u1ec7t gi\u1eefa ng\u01b0\u1eddi d\u00f9ng th\u1ef1c v\u00e0 c\u00e1c ch\u01b0\u01a1ng tr\u00ecnh m\u00e1y t\u00ednh t\u1ef1 \u0111\u1ed9ng (bot). D\u01b0\u1edbi \u0111\u00e2y l\u00e0 c\u00e1c b\u01b0\u1edbc c\u01a1 b\u1ea3n c\u1ee7a nguy\u00ean t\u1eafc ho\u1ea1t \u0111\u1ed9ng c\u1ee7a ch\u00fang.<\/p>\n

B\u01b0\u1edbc 1: H\u1ec7 th\u1ed1ng t\u1ea1o ra m\u1ed9t th\u1eed th\u00e1ch m\u00e0 con ng\u01b0\u1eddi c\u00f3 th\u1ec3 gi\u1ea3i quy\u1ebft. \u0110\u00f3 th\u01b0\u1eddng l\u00e0 th\u00f4ng qua vi\u1ec7c hi\u1ec3n th\u1ecb c\u00e1c h\u00ecnh \u1ea3nh ho\u1eb7c \u00e2m thanh ch\u1ee9a c\u00e1c k\u00fd t\u1ef1 ho\u1eb7c \u0111\u1ed1i t\u01b0\u1ee3ng.<\/p>\n

B\u01b0\u1edbc 2: Hi\u1ec3n th\u1ecb th\u1eed th\u00e1ch cho ng\u01b0\u1eddi d\u00f9ng. Th\u1eed th\u00e1ch \u0111\u01b0\u1ee3c hi\u1ec3n th\u1ecb tr\u00ean giao di\u1ec7n ng\u01b0\u1eddi d\u00f9ng. \u0110\u00f3 th\u01b0\u1eddng l\u00e0 trong m\u1ed9t \u00f4 ki\u1ec3m (checkbox) ho\u1eb7c m\u1ed9t bi\u1ec3u m\u1eabu nh\u1eadp li\u1ec7u.<\/p>\n

B\u01b0\u1edbc 3: Ng\u01b0\u1eddi d\u00f9ng ph\u1ea3i th\u1ef1c hi\u1ec7n h\u00e0nh \u0111\u1ed9ng c\u1ee5 th\u1ec3 \u0111\u1ec3 gi\u1ea3i quy\u1ebft th\u1eed th\u00e1ch. Ch\u1eb3ng h\u1ea1n h\u1ecd ph\u1ea3i ch\u1ecdn c\u00e1c h\u00ecnh \u1ea3nh c\u00f3 ch\u1ee9a \u0111\u1ed1i t\u01b0\u1ee3ng c\u1ee5 th\u1ec3. Ho\u1eb7c h\u1ecd ph\u1ea3i nh\u1eadp l\u1ea1i c\u00e1c k\u00fd t\u1ef1 ho\u1eb7c t\u1eeb \u0111\u01b0\u1ee3c hi\u1ec3n th\u1ecb.<\/p>\n

B\u01b0\u1edbc 4: X\u00e1c minh k\u1ebft qu\u1ea3. H\u1ec7 th\u1ed1ng sau \u0111\u00f3 x\u00e1c minh k\u1ebft qu\u1ea3 \u0111\u01b0\u1ee3c nh\u1eadp l\u1ea1i b\u1edfi ng\u01b0\u1eddi d\u00f9ng \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh xem h\u1ecd \u0111\u00e3 ho\u00e0n th\u00e0nh th\u1eed th\u00e1ch m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c hay kh\u00f4ng.<\/p>\n

B\u01b0\u1edbc 5: Truy c\u1eadp \u0111\u01b0\u1ee3c c\u1ea5p cho ng\u01b0\u1eddi d\u00f9ng. N\u1ebfu ng\u01b0\u1eddi d\u00f9ng v\u01b0\u1ee3t qua th\u1eed th\u00e1ch th\u00e0nh c\u00f4ng, h\u1ecd \u0111\u01b0\u1ee3c c\u1ea5p quy\u1ec1n truy c\u1eadp v\u00e0o t\u00e0i nguy\u00ean ho\u1eb7c d\u1ecbch v\u1ee5 m\u00e0 h\u1ecd \u0111ang y\u00eau c\u1ea7u.<\/p>\n

\"CAPTCHA-11\"
C\u00e1ch ho\u1ea1t \u0111\u1ed9ng c\u1ee7a m\u00e3 CAPTCHA<\/figcaption><\/figure>\n

C\u00e1c th\u1eed th\u00e1ch c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf theo nhi\u1ec1u h\u00ecnh th\u1ee9c kh\u00e1c nhau. Nh\u1eefng h\u00ecnh th\u1ee9c \u0111\u00f3 bao g\u1ed3m nh\u1eadp k\u00fd t\u1ef1, ch\u1ecdn h\u00ecnh \u1ea3nh, nh\u1eadn di\u1ec7n \u00e2m thanh, v\u00e0 c\u00e1c ph\u01b0\u01a1ng ph\u00e1p kh\u00e1c. M\u1eb7c d\u00f9 \u0111\u00f4i khi g\u00e2y phi\u1ec1n to\u00e1i cho ng\u01b0\u1eddi d\u00f9ng, nh\u01b0ng \u0111\u00e2y v\u1eabn l\u00e0 m\u1ed9t c\u00f4ng c\u1ee5 hi\u1ec7u qu\u1ea3 \u0111\u1ec3 ng\u0103n ch\u1eb7n c\u00e1c ho\u1ea1t \u0111\u1ed9ng t\u1ef1 \u0111\u1ed9ng kh\u00f4ng mong mu\u1ed1n tr\u00ean Internet.<\/p>\n

K\u1ebft lu\u1eadn<\/h2>\n

Tr\u00ean \u0111\u00e2y l\u00e0 nh\u1eefng th\u00f4ng tin v\u1ec1 m\u00e3 CAPTCHA. C\u00f3 th\u1ec3 n\u00f3i \u0111\u00e2y l\u00e0 m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c b\u1ea3o m\u1eadt tuy \u0111\u01a1n gi\u1ea3n m\u00e0 hi\u1ec7u qu\u1ea3. N\u00f3 nh\u01b0 trang b\u1ecb th\u00eam m\u1ed9t l\u1edbp r\u00e0o tr\u01b0\u1edbc s\u1ef1 t\u1ea5n c\u00f4ng t\u1eeb c\u00e1c t\u00e0i kho\u1ea3n gi\u1ea3 m\u1ea1o. Hy v\u1ecdng b\u1ea1n c\u00f3 th\u1ec3 \u00e1p d\u1ee5ng th\u00e0nh c\u00f4ng cho h\u1ec7 th\u1ed1ng web c\u1ee7a m\u00ecnh nh\u00e9. \u0110\u1eebng qu\u00ean kh\u00e1m ph\u00e1 th\u00eam c\u00e1c th\u00f4ng tin th\u00fa v\u1ecb kh\u00e1c v\u1ec1 an ninh m\u1ea1ng t\u1ea1i \u0111\u00e2y.<\/p>\n

XEM TH\u00caM:<\/p>\n