{"id":12375533,"date":"2026-03-18T06:05:38","date_gmt":"2026-03-17T22:05:38","guid":{"rendered":"https:\/\/www.likacloud.com\/knowledge\/cdn%e5%8a%a0%e9%80%9f%e5%8e%9f%e7%90%86%e5%85%a8%e8%a7%a3%e6%9e%90%ef%bc%9a%e4%bb%8edns%e8%a7%a3%e6%9e%90%e5%88%b0%e7%bc%93%e5%ad%98%e7%ad%96%e7%95%a5%e7%9a%84%e5%ae%8c%e6%95%b4%e6%8c%87%e5%8d%97\/"},"modified":"2026-03-18T06:43:49","modified_gmt":"2026-03-17T22:43:49","slug":"cdn-acceleration-principles-dns-caching-guide","status":"publish","type":"knowledge_post","link":"https:\/\/www.likacloud.com\/vi\/knowledge\/cdn\/cdn-acceleration-principles-dns-caching-guide\/","title":{"rendered":"H\u01b0\u1edbng d\u1eabn to\u00e0n di\u1ec7n v\u1ec1 nguy\u00ean l\u00fd CDN: T\u1eeb ph\u00e2n gi\u1ea3i DNS \u0111\u1ebfn chi\u1ebfn l\u01b0\u1ee3c b\u1ed9 nh\u1edb \u0111\u1ec7m"},"content":{"rendered":"

Trong th\u1ebf gi\u1edbi internet ng\u00e0y nay, ng\u01b0\u1eddi d\u00f9ng \u0111\u1eb7t ra nh\u1eefng y\u00eau c\u1ea7u g\u1ea7n nh\u01b0 kh\u1eaft khe \u0111\u1ed1i v\u1edbi t\u1ed1c \u0111\u1ed9 t\u1ea3i trang web v\u00e0 \u1ee9ng d\u1ee5ng. Ch\u1ec9 m\u1ed9t v\u00e0i gi\u00e2y tr\u1ec5 c\u0169ng c\u00f3 th\u1ec3 khi\u1ebfn ng\u01b0\u1eddi d\u00f9ng r\u1eddi b\u1ecf trang web \u0111\u00f3. \u0110\u1ec3 \u0111\u1ed1i ph\u00f3 v\u1edbi th\u00e1ch th\u1ee9c n\u00e0y, m\u1ea1ng l\u01b0\u1edbi ph\u00e2n ph\u1ed1i n\u1ed9i dung (Content Distribution Network \u2013 CDN) \u0111\u00e3 ra \u0111\u1eddi, s\u1eed d\u1ee5ng m\u1ed9t lo\u1ea1t c\u00f4ng ngh\u1ec7 tinh vi \u0111\u1ec3 ph\u00e2n ph\u1ed1i n\u1ed9i dung t\u0129nh v\u00e0 \u0111\u1ed9ng m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3 \u0111\u1ebfn ng\u01b0\u1eddi d\u00f9ng tr\u00ean to\u00e0n th\u1ebf gi\u1edbi. Vi\u1ec7c hi\u1ec3u r\u00f5 c\u01a1 ch\u1ebf ho\u1ea1t \u0111\u1ed9ng c\u1ee7a CDN l\u00e0 r\u1ea5t quan tr\u1ecdng \u0111\u1ed1i v\u1edbi c\u00e1c nh\u00e0 ph\u00e1t tri\u1ec3n v\u00e0 nh\u00e2n vi\u00ean v\u1eadn h\u00e0nh h\u1ec7 th\u1ed1ng, nh\u1eb1m n\u00e2ng cao tr\u1ea3i nghi\u1ec7m ng\u01b0\u1eddi d\u00f9ng.<\/p>\n\n\n\n

Kh\u00e1i ni\u1ec7m c\u1ed1t l\u00f5i v\u00e0 ki\u1ebfn tr\u00fac c\u1ee7a CDN<\/h2>\n\n\n\n

CDN (Content Delivery Network) l\u00e0 m\u1ed9t h\u1ec7 th\u1ed1ng ph\u00e2n ph\u1ed1i n\u1ed9i dung, v\u1edbi nguy\u00ean l\u00fd c\u01a1 b\u1ea3n l\u00e0 \u201ctruy c\u1eadp t\u1eeb ngu\u1ed3n g\u1ea7n nh\u1ea5t\u201d. H\u1ec7 th\u1ed1ng n\u00e0y x\u00e2y d\u1ef1ng m\u1ed9t m\u1ea1ng \u1ea3o th\u00f4ng minh b\u1eb1ng c\u00e1ch tri\u1ec3n khai c\u00e1c m\u00e1y ch\u1ee7 tr\u00ean kh\u1eafp m\u1ea1ng l\u01b0\u1edbi. D\u1ef1a tr\u00ean d\u1eef li\u1ec7u th\u1eddi gian th\u1ef1c v\u1ec1 l\u01b0u l\u01b0\u1ee3ng truy c\u1eadp, t\u00ecnh tr\u1ea1ng k\u1ebft n\u1ed1i v\u00e0 t\u1ea3i c\u1ee7a t\u1eebng m\u00e1y ch\u1ee7, c\u0169ng nh\u01b0 kho\u1ea3ng c\u00e1ch \u0111\u1ebfn ng\u01b0\u1eddi d\u00f9ng v\u00e0 th\u1eddi gian ph\u1ea3n h\u1ed3i, CDN s\u1ebd t\u1ef1 \u0111\u1ed9ng \u0111\u1ecbnh tuy\u1ebfn y\u00eau c\u1ea7u c\u1ee7a ng\u01b0\u1eddi d\u00f9ng \u0111\u1ebfn m\u00e1y ch\u1ee7 ph\u1ee5c v\u1ee5 n\u1eb1m g\u1ea7n h\u1ecd nh\u1ea5t.<\/p>\n\n\n\n

C\u1ea5u tr\u00fac c\u01a1 b\u1ea3n c\u1ee7a m\u1ea1ng CDN (Content Delivery Network)<\/h3>\n\n\n\n

M\u1ed9t m\u1ea1ng l\u01b0\u1edbi CDN (Content Delivery Network) \u0111i\u1ec3n h\u00ecnh ch\u1ee7 y\u1ebfu bao g\u1ed3m hai ph\u1ea7n ch\u00ednh: c\u00e1c n\u00fat trung t\u00e2m (central nodes) v\u00e0 c\u00e1c n\u00fat bi\u00ean (edge nodes). C\u00e1c n\u00fat trung t\u00e2m, c\u00f2n \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 m\u00e1y ch\u1ee7 ngu\u1ed3n (source servers), l\u00e0 ngu\u1ed3n cung c\u1ea5p n\u1ed9i dung cu\u1ed1i c\u00f9ng, l\u01b0u tr\u1eef t\u1ea5t c\u1ea3 d\u1eef li\u1ec7u g\u1ed1c. C\u00e1c n\u00fat bi\u00ean l\u00e0 nh\u1eefng m\u00e1y ch\u1ee7 \u0111\u1ec7m \u0111\u01b0\u1ee3c ph\u00e2n b\u1ed1 r\u1ed9ng r\u00e3i tr\u00ean kh\u1eafp th\u1ebf gi\u1edbi; ch\u00fang l\u1ea5y n\u1ed9i dung t\u1eeb c\u00e1c n\u00fat trung t\u00e2m, l\u01b0u tr\u1eef n\u00f3 v\u00e0o b\u1ed9 \u0111\u1ec7m, v\u00e0 sau \u0111\u00f3 ph\u1ee5c v\u1ee5 tr\u1ef1c ti\u1ebfp c\u00e1c y\u00eau c\u1ea7u t\u1eeb ng\u01b0\u1eddi d\u00f9ng cu\u1ed1i. C\u1ea5u tr\u00fac ph\u00e2n t\u00e1n n\u00e0y l\u00e0 n\u1ec1n t\u1ea3ng v\u1eadt l\u00fd cho vi\u1ec7c t\u0103ng t\u1ed1c truy c\u1eadp n\u1ed9i dung th\u00f4ng qua CDN.<\/p>\n

\u0110\u1ecdc th\u00eam Ph\u00e2n t\u00edch s\u00e2u v\u1ec1 nguy\u00ean l\u00fd k\u1ef9 thu\u1eadt CDN, \u01b0u \u0111i\u1ec3m c\u1ee7a n\u00f3, v\u00e0 c\u00e1ch l\u1ef1a ch\u1ecdn nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 t\u1ed1t nh\u1ea5t<\/a>\u3002<\/p>\n\n\n\n\n

Mekanisme truy xu\u1ea5t ngu\u1ed3n (Origin Pulling) v\u00e0 l\u01b0u tr\u1eef \u0111\u1ec7m (Caching)<\/h3>\n\n\n\n

Khi m\u00e1y ch\u1ee7 n\u00fat bi\u00ean (edge node) kh\u00f4ng c\u00f3 n\u1ed9i dung m\u00e0 ng\u01b0\u1eddi d\u00f9ng y\u00eau c\u1ea7u, n\u00f3 c\u1ea7n g\u1eedi y\u00eau c\u1ea7u d\u1eef li\u1ec7u \u0111\u1ebfn m\u00e1y ch\u1ee7 ngu\u1ed3n (source server); qu\u00e1 tr\u00ecnh n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 \u201ckh\u00f4i ph\u1ee5c ngu\u1ed3n d\u1eef li\u1ec7u\u201d (data retrieval from the source). Sau khi nh\u1eadn \u0111\u01b0\u1ee3c d\u1eef li\u1ec7u t\u1eeb m\u00e1y ch\u1ee7 ngu\u1ed3n, m\u00e1y ch\u1ee7 n\u00fat bi\u00ean s\u1ebd l\u01b0u tr\u1eef ch\u00fang v\u00e0o b\u1ed9 nh\u1edb \u0111\u1ec7m (cache). Khi c\u00f3 y\u00eau c\u1ea7u t\u01b0\u01a1ng t\u1ef1 t\u1eeb ng\u01b0\u1eddi d\u00f9ng sau n\u00e0y, m\u00e1y ch\u1ee7 n\u00fat bi\u00ean c\u00f3 th\u1ec3 tr\u1ea3 l\u1eddi ngay l\u1eadp t\u1ee9c m\u00e0 kh\u00f4ng c\u1ea7n ph\u1ea3i g\u1eedi y\u00eau c\u1ea7u l\u1ea1i, t\u1eeb \u0111\u00f3 gi\u1ea3m \u0111\u00e1ng k\u1ec3 \u0111\u1ed9 tr\u1ec5 v\u00e0 \u00e1p l\u1ef1c l\u00ean m\u00e1y ch\u1ee7 ngu\u1ed3n.<\/p>\n\n

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\r\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\\nbunny.net\r\n\t\t\t\t\t\t\t\t\t\r\n\t\t\t<\/div>\r\n\t\t\t\r\n\t\t\t\r\n\t\t\t
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\r\n\t\t\t\t\t\\nbunny.net CDN<\/strong>\r\n\t\t\t\t\t\t\t\t\t<\/div>\r\n\t\t\t<\/div>\r\n\t\t<\/div>\r\n\t\t\t\tChi ph\u00ed ch\u1ec9 t\u1eeb 1 \u0111\u00f4 la m\u1ed7i th\u00e1ng, v\u1edbi m\u1ee9c ph\u00ed r\u00f5 r\u00e0ng v\u00e0 kh\u00f4ng c\u00f3 chi ph\u00ed \u1ea9n. C\u00e1c t\u00ednh n\u0103ng bao g\u1ed3m l\u01b0u tr\u1eef v\u0129nh vi\u1ec5n, gi\u00e1m s\u00e1t theo th\u1eddi gian th\u1ef1c, b\u1ea3o v\u1ec7 DDoS v\u00e0 ch\u1ee9ng ch\u1ec9 SSL mi\u1ec5n ph\u00ed. \u0110\u1eb7c bi\u1ec7t, n\u00f3 c\u00f2n \u0111\u01b0\u1ee3c t\u1ed1i \u01b0u h\u00f3a cho ph\u00e1t tr\u1ef1c tuy\u1ebfn video v\u00e0 cung c\u1ea5p m\u1ed9t m\u00f4 h\u00ecnh thanh to\u00e1n linh ho\u1ea1t theo m\u1ee9c s\u1eed d\u1ee5ng.<\/span>\r\n\t\t\t\t
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Kh\u00f4ng c\u1ea7n th\u1ebb t\u00edn d\u1ee5ng, d\u00f9ng th\u1eed mi\u1ec5n ph\u00ed trong 14 ng\u00e0y<\/div>\r\n\t\t\t\t\t\t\t\t\t\t\t\tTruy c\u1eadp m\u1ea1ng l\u01b0\u1edbi ph\u00e2n ph\u1ed1i n\u1ed9i dung (CDN) c\u1ee7a bunny.net \u2192<\/a>\r\n\t\t\t\t\t\t\t<\/div> \r\n\t\t<\/div>\r\n\t<\/div>\r\n\t\t\r\n\t\r\n\t
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\r\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\u0110\u00e1m\r\n\t\t\t\t\t\t\t\t\t\r\n\t\t\t<\/div>\r\n\t\t\t\r\n\t\t\t\r\n\t\t\t
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\r\n\t\t\t\t\t\u0110\u00e1m m\u00e2y Cloudways Cloudflare Enterprise<\/strong>\r\n\t\t\t\t\t\t\t\t\t<\/div>\r\n\t\t\t<\/div>\r\n\t\t<\/div>\r\n\t\t\t\tG\u00f3i gi\u00e1 d\u1ecbch v\u1ee5 CDN\/WAF c\u1ea5p doanh nghi\u1ec7p c\u1ee7a Cloudflare c\u00f3 c\u00e1c m\u1ee9c ph\u00ed nh\u01b0 sau: t\u1ed1i \u0111a 5 t\u00ean mi\u1ec1n, m\u1ed7i t\u00ean mi\u1ec1n c\u00f3 gi\u00e1 4,99 USD\/th\u00e1ng, bao g\u1ed3m 100GB b\u0103ng th\u00f4ng, v\u00e0 ph\u1ea7n v\u01b0\u1ee3t qu\u00e1 s\u1ebd \u0111\u01b0\u1ee3c t\u00ednh ph\u00ed theo m\u1ee9c ph\u00ed 0,02 USD\/GB.<\/span>\r\n\t\t\t\t
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M\u1ed7i t\u00ean mi\u1ec1n \u0111\u01b0\u1ee3c t\u1eb7ng 100GB l\u01b0u l\u01b0\u1ee3ng truy c\u1eadp<\/div>\r\n\t\t\t\t\t\t\t\t\t\t\t\tTruy c\u1eadp Cloudways Cloudflare Enterprise \u2192<\/a>\r\n\t\t\t\t\t\t\t<\/div> \r\n\t\t<\/div>\r\n\t<\/div>\r\n\t\t\r\n<\/div>\r\n\r\n\r\n\n\n\n\n\n\n\n

DNS Gi\u1ea3i m\u00e3: B\u01b0\u1edbc \u0111\u1ea7u ti\u00ean trong qu\u00e1 tr\u00ecnh l\u1eadp l\u1ecbch tr\u00ecnh th\u00f4ng minh<\/h2>\n\n\n\n

Khi ng\u01b0\u1eddi d\u00f9ng truy c\u1eadp m\u1ed9t trang web \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i v\u1edbi CDN (Content Delivery Network), b\u01b0\u1edbc quan tr\u1ecdng \u0111\u1ea7u ti\u00ean l\u00e0 qu\u00e1 tr\u00ecnh gi\u1ea3i m\u00e3 DNS (Domain Name System). Qu\u00e1 tr\u00ecnh n\u00e0y kh\u00f4ng \u0111\u01a1n thu\u1ea7n l\u00e0 tr\u1ea3 v\u1ec1 \u0111\u1ecba ch\u1ec9 IP c\u1ee7a m\u00e1y ch\u1ee7 ngu\u1ed3n, m\u00e0 l\u00e0 kh\u1edfi \u0111\u1ea7u cho h\u1ec7 th\u1ed1ng \u0111i\u1ec1u ph\u1ed1i th\u00f4ng minh c\u1ee7a CDN.<\/p>\n\n\n\n

Khi ng\u01b0\u1eddi d\u00f9ng nh\u1eadp \u0111\u1ecba ch\u1ec9 web, h\u1ec7 th\u1ed1ng DNS c\u1ee5c b\u1ed9 s\u1ebd g\u1eedi y\u00eau c\u1ea7u truy v\u1ea5n \u0111\u1ebfn m\u00e1y ch\u1ee7 DNS \u0111\u01b0\u1ee3c \u1ee7y quy\u1ec1n c\u1ee7a t\u00ean mi\u1ec1n \u0111\u00f3. \u0110\u1ed1i v\u1edbi c\u00e1c t\u00ean mi\u1ec1n s\u1eed d\u1ee5ng d\u1ecbch v\u1ee5 CDN (Content Delivery Network), m\u00e1y ch\u1ee7 DNS \u0111\u01b0\u1ee3c \u1ee7y quy\u1ec1n kh\u00f4ng tr\u1ef1c ti\u1ebfp k\u1ebft n\u1ed1i \u0111\u1ebfn m\u00e1y ch\u1ee7 ngu\u1ed3n, m\u00e0 s\u1ebd k\u1ebft n\u1ed1i \u0111\u1ebfn h\u1ec7 th\u1ed1ng DNS th\u00f4ng minh do nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 CDN cung c\u1ea5p. H\u1ec7 th\u1ed1ng DNS th\u00f4ng minh n\u00e0y s\u1ebd l\u1ef1a ch\u1ecdn m\u1ed9t node (n\u00fat) g\u1ea7n ng\u01b0\u1eddi d\u00f9ng nh\u1ea5t v\u00e0 ph\u00f9 h\u1ee3p nh\u1ea5t \u0111\u1ec3 ph\u1ee5c v\u1ee5 y\u00eau c\u1ea7u truy c\u1eadp d\u1ef1a tr\u00ean m\u1ed9t lo\u1ea1t c\u00e1c chi\u1ebfn l\u01b0\u1ee3c ph\u00e2n ph\u1ed1i ph\u1ee9c t\u1ea1p.<\/p>\n\n\n\n

Chi ti\u1ebft v\u1ec1 chi\u1ebfn l\u01b0\u1ee3c l\u1eadp l\u1ecbch (Scheduling Strategy)<\/h3>\n\n\n\n

Chi\u1ebfn l\u01b0\u1ee3c l\u1eadp l\u1ecbch c\u1ee7a DNS th\u00f4ng minh l\u00e0 y\u1ebfu t\u1ed1 then ch\u1ed1t quy\u1ebft \u0111\u1ecbnh hi\u1ec7u su\u1ea5t c\u1ee7a CDN. C\u00e1c chi\u1ebfn l\u01b0\u1ee3c ph\u1ed5 bi\u1ebfn bao g\u1ed3m l\u1eadp l\u1ecbch d\u1ef1a tr\u00ean v\u1ecb tr\u00ed \u0111\u1ecba l\u00fd, t\u1ee9c l\u00e0 d\u1ef1a tr\u00ean th\u00f4ng tin \u0111\u1ecba l\u00fd c\u1ee7a \u0111\u1ecba ch\u1ec9 IP c\u1ee7a ng\u01b0\u1eddi d\u00f9ng \u0111\u1ec3 tr\u1ea3 v\u1ec1 \u0111\u1ecba ch\u1ec9 IP c\u1ee7a n\u00fat g\u1ea7n nh\u1ea5t v\u1ec1 m\u1eb7t v\u1ecb tr\u00ed \u0111\u1ecba l\u00fd. Ngo\u00e0i ra, c\u00f2n c\u00f3 chi\u1ebfn l\u01b0\u1ee3c l\u1eadp l\u1ecbch d\u1ef1a tr\u00ean c\u00e2n b\u1eb1ng t\u1ea3i (load balancing), trong \u0111\u00f3 h\u1ec7 th\u1ed1ng theo d\u00f5i th\u1eddi gian th\u1ef1c t\u00ecnh h\u00ecnh t\u1ea3i c\u1ee7a t\u1eebng n\u00fat bi\u00ean (edge node) v\u00e0 \u0111\u1ecbnh h\u01b0\u1edbng y\u00eau c\u1ea7u c\u1ee7a ng\u01b0\u1eddi d\u00f9ng \u0111\u1ebfn n\u00fat c\u00f3 t\u1ea3i nh\u1eb9 h\u01a1n, nh\u1eb1m tr\u00e1nh t\u00ecnh tr\u1ea1ng qu\u00e1 t\u1ea3i t\u1ea1i m\u1ed9t \u0111i\u1ec3m duy nh\u1ea5t. Nh\u1eefng chi\u1ebfn l\u01b0\u1ee3c ti\u00ean ti\u1ebfn h\u01a1n s\u1ebd k\u1ebft h\u1ee3p th\u00f4ng tin v\u1ec1 t\u00ecnh tr\u1ea1ng m\u1ea1ng th\u1eddi gian th\u1ef1c \u0111\u1ec3 ch\u1ecdn n\u00fat c\u00f3 ch\u1ea5t l\u01b0\u1ee3ng k\u1ebft n\u1ed1i t\u1ed1t nh\u1ea5t v\u00e0 th\u1eddi gian ph\u1ea3n h\u1ed3i nhanh nh\u1ea5t.<\/p>\n\n\n\n

K\u1ebft qu\u1ea3 ph\u00e2n t\u00edch v\u00e0 d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong b\u1ed9 nh\u1edb \u0111\u1ec7m c\u1ee5c b\u1ed9 (local cache)<\/h3>\n\n\n\n

Cu\u1ed1i c\u00f9ng, h\u1ec7 th\u1ed1ng DNS th\u00f4ng minh s\u1ebd tr\u1ea3 v\u1ec1 \u0111\u1ecba ch\u1ec9 IP c\u1ee7a n\u00fat c\u1ea1nh \u0111\u01b0\u1ee3c ch\u1ecdn cho DNS c\u1ee5c b\u1ed9 c\u1ee7a ng\u01b0\u1eddi d\u00f9ng, v\u00e0 qu\u00e1 tr\u00ecnh gi\u1ea3i quy\u1ebft y\u00eau c\u1ea7u \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n th\u00f4ng qua tr\u00ecnh duy\u1ec7t. K\u1ebft qu\u1ea3 gi\u1ea3i quy\u1ebft n\u00e0y th\u01b0\u1eddng \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong b\u1ed9 nh\u1edb \u0111\u1ec7m (cache) c\u1ea3 \u1edf c\u1ea5p \u0111\u1ed9 c\u1ee5c b\u1ed9 l\u1eabn c\u00e1c m\u00e1y ch\u1ee7 DNS \u1edf c\u00e1c t\u1ea7ng kh\u00e1c nhau trong m\u1ed9t th\u1eddi gian nh\u1ea5t \u0111\u1ecbnh; \u0111i\u1ec1u n\u00e0y gi\u00fap t\u0103ng t\u1ed1c \u0111\u1ed9 truy c\u1eadp sau n\u00e0y. Tuy nhi\u00ean, \u0111i\u1ec1u n\u00e0y c\u0169ng c\u00f3 ngh\u0129a l\u00e0 khi c\u00f3 s\u1ef1 c\u1ed1 v\u1edbi n\u00fat c\u1ea1nh ho\u1eb7c thay \u0111\u1ed5i trong m\u1ea1ng, ng\u01b0\u1eddi d\u00f9ng s\u1ebd ph\u1ea3i ch\u1edd cho \u0111\u1ebfn khi d\u1eef li\u1ec7u trong b\u1ed9 nh\u1edb \u0111\u1ec7m h\u1ebft h\u1ea1n ho\u1eb7c th\u1ef1c hi\u1ec7n thao t\u00e1c l\u00e0m m\u1edbi (refresh) \u0111\u1ec3 chuy\u1ec3n<\/p>\n

\u0110\u1ecdc th\u00eam Ph\u00e2n t\u00edch s\u00e2u v\u1ec1 CDN: C\u00e1ch l\u1ef1a ch\u1ecdn v\u00e0 s\u1eed d\u1ee5ng m\u1ea1ng ph\u00e2n ph\u1ed1i n\u1ed9i dung \u0111\u1ec3 t\u1ed1i \u01b0u hi\u1ec7u su\u1ea5t website<\/a>\u3002<\/p>\n\n\n\n\n

X\u1eed l\u00fd y\u00eau c\u1ea7u v\u00e0 truy\u1ec1n t\u1ea3i n\u1ed9i dung<\/h2>\n\n\n\n

Sau khi nh\u1eadn \u0111\u01b0\u1ee3c \u0111\u1ecba ch\u1ec9 IP c\u1ee7a n\u00fat c\u1ea1nh (edge node), tr\u00ecnh duy\u1ec7t c\u1ee7a ng\u01b0\u1eddi d\u00f9ng s\u1ebd k\u1ebft n\u1ed1i v\u1edbi n\u00fat \u0111\u00f3 v\u00e0 g\u1eedi y\u00eau c\u1ea7u truy c\u1eadp n\u1ed9i dung. L\u00fac n\u00e0y, n\u00fat c\u1ea1nh \u0111\u00f3ng vai tr\u00f2 l\u00e0 trung gian truy\u1ec1n th\u00f4ng v\u00e0 b\u1ed9 t\u0103ng t\u1ed1c (accelerator).<\/p>\n\n\n\n

Cache hit v\u00e0 cache miss<\/h3>\n\n\n\n

Sau khi nh\u1eadn \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u, n\u00fat bi\u00ean (edge node) s\u1ebd ki\u1ec3m tra xem li\u1ec7u t\u00e0i nguy\u00ean \u0111\u01b0\u1ee3c y\u00eau c\u1ea7u c\u00f3 t\u1ed3n t\u1ea1i trong b\u1ed9 nh\u1edb \u0111\u1ec7m (cache) \u0111\u1ecba ph\u01b0\u01a1ng hay kh\u00f4ng, \u0111\u1ed3ng th\u1eddi x\u00e1c \u0111\u1ecbnh xem t\u00e0i nguy\u00ean \u0111\u00f3 c\u00f3 h\u1ebft h\u1ea1n hay ch\u01b0a (d\u1ef1a tr\u00ean c\u00e1c th\u00f4ng tin trong ph\u1ea7n \u0111\u1ea7u HTTP li\u00ean quan \u0111\u1ebfn ki\u1ec3m so\u00e1t b\u1ed9 nh\u1edb \u0111\u1ec7m). N\u1ebfu t\u00e0i nguy\u00ean t\u1ed3n t\u1ea1i v\u00e0 v\u1eabn c\u00f2n h\u1ee3p l\u1ec7, vi\u1ec7c truy xu\u1ea5t s\u1ebd \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n tr\u1ef1c ti\u1ebfp t\u1eeb b\u1ed9 nh\u1edb \u0111\u1ec7m, mang l\u1ea1i t\u1ed1c \u0111\u1ed9 truy xu\u1ea5t nhanh nh\u1ea5t. Ng\u01b0\u1ee3c l\u1ea1i, n\u1ebfu t\u00e0i nguy\u00ean kh\u00f4ng t\u1ed3n t\u1ea1i ho\u1eb7c \u0111\u00e3 h\u1ebft h\u1ea1n, n\u00fat bi\u00ean s\u1ebd ph\u1ea3i g\u1eedi y\u00eau c\u1ea7u v\u1ec1 m\u00e1y ch\u1ee7 ngu\u1ed3n (origin server) \u0111\u1ec3 l\u1ea5y th\u00f4ng tin m\u1edbi nh\u1ea5t.<\/p>\n\n\n\n

T\u1ed1i \u01b0u h\u00f3a giao th\u1ee9c v\u00e0 t\u0103ng t\u1ed1c truy\u1ec1n t\u1ea3i<\/h3>\n\n\n\n

Trong qu\u00e1 tr\u00ecnh truy\u1ec1n t\u1ea3i n\u1ed9i dung, CDN (Content Delivery Network) s\u1ebd \u00e1p d\u1ee5ng nhi\u1ec1u bi\u1ec7n ph\u00e1p t\u1ed1i \u01b0u h\u00f3a kh\u00e1c nhau. V\u00ed d\u1ee5, h\u1ed7 tr\u1ee3 c\u00e1c giao th\u1ee9c HTTP\/2 ho\u1eb7c HTTP\/3 m\u1edbi nh\u1ea5t \u0111\u1ec3 th\u1ef1c hi\u1ec7n k\u1ef9 thu\u1eadt \u0111a lu\u1ed3ng (multiplexing) v\u00e0 n\u00e9n th\u00f4ng tin trong ph\u1ea7n ti\u00eau \u0111\u1ec1 (header compression), t\u1eeb \u0111\u00f3 gi\u1ea3m \u0111\u1ed9 tr\u1ec5 k\u1ebft n\u1ed1i. \u0110\u1ed1i v\u1edbi c\u00e1c t\u1ec7p l\u1edbn ho\u1eb7c video, CDN s\u1eed d\u1ee5ng c\u00e1c k\u1ef9 thu\u1eadt nh\u01b0 truy\u1ec1n t\u1ea3i theo ph\u1ea7n (segmented transmission) v\u00e0 \u0111i\u1ec1u ch\u1ec9nh t\u1ed1c \u0111\u1ed9 truy\u1ec1n d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch dinh h\u1ed3ng (dynamic bitrate adjustment). Ngo\u00e0i ra, c\u00e1c nh\u00e0 cung c\u1ea5p CDN s\u1edf h\u1eefu m\u1ea1ng l\u01b0\u1edbi c\u1ed1t l\u00f5i \u0111\u01b0\u1ee3c t\u1ed1i \u01b0u h\u00f3a v\u00e0 c\u00f3 k\u1ebft n\u1ed1i \u0111\u1ed1i x\u1ee9ng v\u1edbi nhi\u1ec1u nh\u00e0 m\u1ea1ng kh\u00e1c nhau, gi\u00fap h\u1ecd c\u00f3 th\u1ec3 l\u1ef1a ch\u1ecdn \u0111\u01b0\u1eddng truy\u1ec1n t\u1ed1t nh\u1ea5t, gi\u1ea3m t\u00ecnh tr\u1ea1ng qu\u00e1 t\u1ea3i v\u00e0 m\u1ea5t g\u00f3i d\u1eef li\u1ec7u trong qu\u00e1 tr\u00ecnh truy\u1ec1n t\u1ea3i<\/p>\n\n\n\n

Chi\u1ebfn l\u01b0\u1ee3c l\u01b0u tr\u1eef \u0111\u1ec7m (Cache Strategy): S\u1ef1 c\u00e2n b\u1eb1ng gi\u1eefa hi\u1ec7u n\u0103ng v\u00e0 t\u00ednh nh\u1ea5t qu\u00e1n<\/h2>\n\n\n\n

Chi\u1ebfn l\u01b0\u1ee3c l\u01b0u tr\u1eef \u0111\u1ec7m (cache strategy) l\u00e0 linh h\u1ed3n c\u1ee7a CDN (Content Delivery Network \u2013 M\u1ea1ng Ph\u00e2n ph\u1ed1i N\u1ed9i dung); n\u00f3 quy\u1ebft \u0111\u1ecbnh th\u1eddi gian n\u1ed9i dung \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef tr\u00ean c\u00e1c node (n\u00fat) \u1edf periphery (b\u00ean ngo\u00e0i trung t\u00e2m x\u1eed l\u00fd) v\u00e0 c\u00e1ch th\u1ee9c n\u1ed9i dung \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt. \u0110i\u1ec1u n\u00e0y \u1ea3nh h\u01b0\u1edfng tr\u1ef1c ti\u1ebfp \u0111\u1ebfn m\u1ee9c<\/p>\n\n\n\n

Ki\u1ec3m so\u00e1t \u0111\u1ec7m d\u1ef1a tr\u00ean ti\u00eau \u0111\u1ec1 HTTP<\/h3>\n\n\n\n

C\u00e1c chi\u1ebfn l\u01b0\u1ee3c l\u01b0u tr\u1eef \u0111\u1ec7m (cache) ph\u1ed5 bi\u1ebfn nh\u1ea5t \u0111\u01b0\u1ee3c ki\u1ec3m so\u00e1t b\u1edfi m\u00e1y ch\u1ee7 ngu\u1ed3n th\u00f4ng qua c\u00e1c ti\u00eau \u0111\u1ec1 ph\u1ea3n h\u1ed3i HTTP (HTTP response headers).Cache-Control<\/code> In the header section\u2026 max-age<\/code> L\u1ec7nh n\u00e0y x\u00e1c \u0111\u1ecbnh th\u1eddi gian l\u01b0u tr\u1eef t\u1ed1i \u0111a (cache time) cho t\u00e0i nguy\u00ean.Expires<\/code> Ph\u1ea7n \u0111\u1ea7u (header) ch\u1ec9 \u0111\u1ecbnh m\u1ed9t th\u1eddi gian h\u1ebft h\u1ea1n tuy\u1ec7t \u0111\u1ed1i. C\u00e1c n\u00fat \u0111\u1ea7u cu\u1ed1i (edge nodes) c\u1ee7a CDN s\u1ebd tu\u00e2n th\u1ee7 nghi\u00eam ng\u1eb7t c\u00e1c ch\u1ec9 th\u1ecb n\u00e0y. Ngo\u00e0i ra,s-maxage<\/code> Nh\u1eefng l\u1ec7nh n\u00e0y \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng ri\u00eang \u0111\u1ec3 ch\u1ec9 \u0111\u1ecbnh th\u1eddi gian l\u01b0u tr\u1eef d\u1eef li\u1ec7u trong b\u1ed9 \u0111\u1ec7m \u0111\u01b0\u1ee3c chia s\u1ebb (ch\u1eb3ng h\u1ea1n nh\u01b0 b\u1ed9 \u0111\u1ec7m CDN \u2013 Content Delivery Network).<\/p>\n\n\n\n

Mekanisme x\u00e1c th\u1ef1c v\u00e0 l\u00e0m m\u1edbi (Verification and Refresh Mechanism)<\/h3>\n\n\n\n

\u0110\u1ec3 \u0111\u1ea1t \u0111\u01b0\u1ee3c s\u1ef1 c\u00e2n b\u1eb1ng gi\u1eefa vi\u1ec7c l\u01b0u tr\u1eef n\u1ed9i dung trong b\u1ed9 \u0111\u1ec7m (cache) v\u00e0 vi\u1ec7c c\u1eadp nh\u1eadt n\u1ed9i dung m\u1edbi, c\u00e1c h\u1ec7 th\u1ed1ng CDN (Content Delivery Network) h\u1ed7 tr\u1ee3 c\u00e1c c\u01a1 ch\u1ebf x\u00e1c th\u1ef1c (validation mechanisms). Khi th\u1eddi gian l\u01b0u tr\u1eef trong b\u1ed9 \u0111\u1ec7m h\u1ebft h\u1ea1n, c\u00e1c n\u00fat \u0111\u1ea7u cu\u1ed1i (edge nodes) s\u1ebd kh\u00f4ng ngay l\u1eadp t\u1ee9c x\u00f3a n\u1ed9i dung c\u0169, m\u00e0 thay v\u00e0o \u0111\u00f3 s\u1ebd g\u1eedi m If-Modified-Since<\/code> \u6216 If-None-Match<\/code> Ph\u1ea7n \u0111\u1ea7u (Header): N\u1ebfu n\u1ed9i dung tr\u00ean m\u00e1y ch\u1ee7 ngu\u1ed3n kh\u00f4ng thay \u0111\u1ed5i, tr\u1ea1ng th\u00e1i 304 s\u1ebd \u0111\u01b0\u1ee3c tr\u1ea3 v\u1ec1; c\u00e1c n\u00fat chuy\u1ec3n ti\u1ebfp (edge nodes) c\u00f3 th\u1ec3 ti\u1ebfp t\u1ee5c s\u1eed d\u1ee5ng d\u1eef li\u1ec7u \u0111\u00e3 \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong b\u1ed9 nh\u1edb \u0111\u1ec7m (cache) v\u00e0 c\u1eadp nh\u1eadt th\u1eddi h\u1ea1n hi\u1ec7u l\u1ef1c c\u1ee7a ch\u00fang. N\u1ebfu n\u1ed9i dung \u0111\u00e3 thay \u0111\u1ed5i,<\/p>\n

\u0110\u1ecdc th\u00eam Gi\u1ea3i th\u00edch chi ti\u1ebft v\u1ec1 c\u00f4ng ngh\u1ec7 CDN: H\u01b0\u1edbng d\u1eabn to\u00e0n di\u1ec7n t\u1eeb nguy\u00ean l\u00fd ki\u1ebfn tr\u00fac \u0111\u1ebfn t\u1ed1i \u01b0u h\u00f3a hi\u1ec7u n\u0103ng<\/a>\u3002<\/p>\n\n\n\n\n

L\u00e0m m\u1edbi b\u1ed9 nh\u1edb cache ch\u1ee7 \u0111\u1ed9ng v\u00e0 th\u1ee5 \u0111\u1ed9ng<\/h3>\n\n\n\n

Ngo\u00e0i vi\u1ec7c d\u1ef1a v\u00e0o th\u1eddi gian h\u1ebft h\u1ea1n, CDN c\u00f2n cung c\u1ea5p c\u00e1c giao di\u1ec7n \u0111\u1ec3 th\u1ef1c hi\u1ec7n vi\u1ec7c l\u00e0m m\u1edbi n\u1ed9i dung m\u1ed9t c\u00e1ch t\u1ef1 \u0111\u1ed9ng. Khi n\u1ed9i dung tr\u00ean m\u00e1y ch\u1ee7 ngu\u1ed3n \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt, nh\u00e2n vi\u00ean v\u1eadn h\u00e0nh c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng giao di\u1ec7n \u0111i\u1ec1u khi\u1ec3n ho\u1eb7c API do nh\u00e0 cung c\u1ea5p CDN cung c\u1ea5p \u0111\u1ec3 x\u00f3a b\u1ecf d\u1eef li\u1ec7u \u0111\u00e3 \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong b\u1ed9 \u0111\u1ec7m (cache) t\u1ea1i c\u00e1c node edge, bu\u1ed9c ng\u01b0\u1eddi d\u00f9ng ph\u1ea3i truy c\u1eadp l\u1ea1i m\u00e1y ch\u1ee7 ngu\u1ed3n \u0111\u1ec3 t\u1ea3i d\u1eef li\u1ec7u m\u1edbi m\u1ed7i l\u1ea7n s\u1eed d\u1ee5ng d\u1ecbch v\u1ee5. \u0110\u00e2y l\u00e0 m\u1ed9t bi\u1ec7n ph\u00e1p hi\u1ec7u qu\u1ea3 \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u00ednh th\u1eddi gian th\u1ef1c c\u1ee7a n\u1ed9i dung, nh\u01b0ng c\u1ea7n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng m\u1ed9t c\u00e1ch th\u1eadn tr\u1ecdng v\u00ec vi\u1ec7c l\u00e0m m\u1edbi qu\u00e1 th\u01b0\u1eddng xuy\u00ean c\u00f3 th\u1ec3 l\u00e0m t\u0103ng \u0111\u00e1ng k\u1ec3 t\u1ea3i l\u01b0\u1ee3ng tr\u00ean m\u00e1y ch\u1ee7 ngu\u1ed3n<\/p>\n\n\n\n

T\u00f3m l\u1ea1i<\/h2>\n\n\n\n

Vi\u1ec7c t\u0103ng t\u1ed1c hi\u1ec7u su\u1ea5t c\u1ee7a CDN kh\u00f4ng ph\u1ea3i l\u00e0 \u0111i\u1ec1u k\u1ef3 di\u1ec7u, m\u00e0 l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a m\u1ed9t h\u1ec7 th\u1ed1ng c\u00f4ng ngh\u1ec7 \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf m\u1ed9t c\u00e1ch ch\u1eb7t ch\u1ebd v\u00e0 li\u00ean k\u1ebft ch\u1eb7t ch\u1ebd v\u1edbi nhau. T\u1eeb vi\u1ec7c ph\u00e2n t\u00edch DNS th\u00f4ng minh \u0111\u1ec3 \u0111\u1ecbnh h\u01b0\u1edbng ng\u01b0\u1eddi d\u00f9ng \u0111\u1ebfn n\u00fat ph\u1ee5c v\u1ee5 t\u1ed1i \u01b0u, \u0111\u1ebfn vi\u1ec7c x\u1eed l\u00fd y\u00eau c\u1ea7u b\u1eb1ng c\u00e1c chi\u1ebfn l\u01b0\u1ee3c l\u01b0u tr\u1eef \u0111\u1ec7m hi\u1ec7u qu\u1ea3 t\u1ea1i c\u00e1c n\u00fat edge, cho \u0111\u1ebfn c\u00e1c b\u01b0\u1edbc t\u1ed1i \u01b0u h\u00f3a trong qu\u00e1 tr\u00ecnh truy xu\u1ea5t v\u00e0 truy\u1ec1n d\u1eef li\u1ec7u ngu\u1ed3n, m\u1ed7i kh\u00e2u \u0111\u1ec1u nh\u1eb1m m\u1ee5c \u0111\u00edch r\u00fat ng\u1eafn kho\u1ea3ng c\u00e1ch \u201ccu\u1ed1i c\u00f9ng\u201d gi\u1eefa n\u1ed9i dung v\u00e0 ng\u01b0\u1eddi d\u00f9ng. Vi\u1ec7c hi\u1ec3u r\u00f5 to\u00e0n b\u1ed9 quy tr\u00ecnh t\u1eeb DNS \u0111\u1ebfn l\u01b0u tr\u1eef \u0111\u1ec7m s\u1ebd gi\u00fap ch\u00fang ta c\u1ea5u h\u00ecnh v\u00e0 s\u1eed d\u1ee5ng CDN m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3 h\u01a1n trong th\u1ef1c t\u1ebf, \u0111\u1ea3m b\u1ea3o t\u00ednh nh\u1ea5t qu\u00e1n c\u1ee7a n\u1ed9i dung \u0111\u1ed3ng th\u1eddi mang l\u1ea1i tr\u1ea3i nghi\u1ec7m truy c\u1eadp nhanh ch\u00f3ng v\u00e0 \u1ed5n \u0111\u1ecbnh cho ng\u01b0\u1eddi d\u00f9ng, t\u1eeb \u0111\u00f3 gi\u00fap ch\u00fang ta gi\u00e0nh \u0111\u01b0\u1ee3c l\u1ee3i th\u1ebf c\u1ea1nh tranh quan tr\u1ecdng trong th\u1eddi \u0111\u1ea1i k\u1ef9 thu\u1eadt s\u1ed1.<\/p>\n\n\n\n

FAQ \u5e38\u89c1\u95ee\u9898<\/h2>\n\n\n\n

CDN ch\u1ee7 y\u1ebfu t\u0103ng t\u1ed1c lo\u1ea1i n\u1ed9i dung n\u00e0o?<\/h3>\n\n\n\n

CDN ch\u1ee7 y\u1ebfu \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 t\u0103ng t\u1ed1c \u0111\u1ed9 truy c\u1eadp c\u00e1c n\u1ed9i dung t\u0129nh, ch\u1eb3ng h\u1ea1n nh\u01b0 h\u00ecnh \u1ea3nh, b\u1ea3ng \u0111\u1ecbnh d\u1ea1ng CSS, t\u1ec7p JavaScript, ph\u00f4ng ch\u1eef, t\u00e0i li\u1ec7u PDF, v\u00e0 c\u00e1c t\u1ec7p \u00e2m thanh\/video. Nh\u1eefng n\u1ed9i dung n\u00e0y th\u01b0\u1eddng kh\u00f4ng thay \u0111\u1ed5i th\u01b0\u1eddng xuy\u00ean v\u00e0 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef m\u1ed9t c\u00e1ch an to\u00e0n t\u1ea1i c\u00e1c m\u00e1y ch\u1ee7 \u0111\u1eb7t \u1edf g\u1ea7n ng\u01b0\u1eddi d\u00f9ng (g\u1ecdi l\u00e0 c\u00e1c \u201cnode edge\u201d).<\/p>\n\n\n\n

\u0110\u1ed1i v\u1edbi n\u1ed9i dung \u0111\u1ed9ng, ch\u1eb3ng h\u1ea1n nh\u01b0 c\u00e1c trang web \u0111\u01b0\u1ee3c t\u1ea1o ra theo th\u1eddi gian th\u1ef1c d\u1ef1a tr\u00ean th\u00f4ng tin ng\u01b0\u1eddi d\u00f9ng ho\u1eb7c ph\u1ea3n h\u1ed3i t\u1eeb c\u00e1c giao di\u1ec7n API, hi\u1ec7u qu\u1ea3 t\u0103ng t\u1ed1c c\u1ee7a c\u00e1c h\u1ec7 th\u1ed1ng CDN truy\u1ec1n th\u1ed1ng l\u00e0 c\u00f3 h\u1ea1n. Tuy nhi\u00ean, c\u00e1c c\u00f4ng ngh\u1ec7 CDN hi\u1ec7n \u0111\u1ea1i c\u0169ng \u0111\u00e3 cung c\u1ea5p c\u00e1c gi\u1ea3i ph\u00e1p t\u0103ng t\u1ed1c cho n\u1ed9i dung \u0111\u1ed9ng b\u1eb1ng c\u00e1ch t\u1ed1i \u01b0u h\u00f3a \u0111\u01b0\u1eddng truy\u1ec1n d\u1eef li\u1ec7u, n\u00e9n d\u1eef li\u1ec7u, t\u00e1i s\u1eed d\u1ee5ng k\u1ebft n\u1ed1i, v.v., nh\u1eb1m n\u00e2ng cao t\u1ed1c \u0111\u1ed9 truy\u1ec1n t\u1ea3i c\u00e1c n\u1ed9i dung n\u00e0y.<\/p>\n\n\n\n

Sau khi s\u1eed d\u1ee5ng CDN (Content Delivery Network \u2013 M\u1ea1ng l\u01b0\u1edbi ph\u00e2n ph\u1ed1i n\u1ed9i dung), l\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng n\u1ed9i dung m\u00e0 ng\u01b0\u1eddi d\u00f9ng nh\u00ecn th\u1ea5y l\u00e0 m\u1edbi nh\u1ea5t?<\/h3>\n\n\n\n

H\u00e3y \u0111\u1ea3m b\u1ea3o r\u1eb1ng vi\u1ec7c c\u1eadp nh\u1eadt n\u1ed9i dung ch\u1ee7 y\u1ebfu d\u1ef1a v\u00e0o c\u00e1c thi\u1ebft l\u1eadp chi\u1ebfn l\u01b0\u1ee3c \u0111\u1ec7m (cache) h\u1ee3p l\u00fd v\u00e0 ch\u1ee9c n\u0103ng l\u00e0m m\u1edbi t\u1ef1 \u0111\u1ed9ng (active refresh). Tr\u00ean m\u00e1y ch\u1ee7 ngu\u1ed3n, h\u00e3y thi\u1ebft l\u1eadp c\u00e1c th\u00f4ng s\u1ed1 ph\u00f9 h\u1ee3p cho c\u00e1c lo\u1ea1i t\u00e0i nguy\u00ean c\u00f3 t\u1ea7n su\u1ea5t c\u1eadp nh\u1eadt kh\u00e1c nhau. Cache-Control<\/code> Ph\u1ea7n \u0111\u1ea7u (nh\u01b0\u2026) max-age<\/code>\u0110\u1ed1i v\u1edbi nh\u1eefng n\u1ed9i dung c\u1ea7n \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt ngay l\u1eadp t\u1ee9c, b\u1ea1n c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng ch\u1ee9c n\u0103ng \u201cL\u00e0m m\u1edbi b\u1ed9 \u0111\u1ec7m\u201d (Refresh Cache) do nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5 CDN cung c\u1ea5p \u0111\u1ec3 x\u00f3a b\u1ed9 \u0111\u1ec7m t\u1ea1m th\u1eddi (edge cache) c\u1ee7a c\u00e1c URL li\u00ean quan sau khi n\u1ed9i dung \u0111\u01b0\u1ee3c \u0111\u0103ng t\u1ea3i.<\/p>\n\n\n\n

Ngo\u00e0i ra, b\u1ea1n c\u0169ng c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng t\u00ednh n\u0103ng phi\u00ean b\u1ea3n h\u00f3a t\u1ec7p tin (file versioning). Khi n\u1ed9i dung c\u1ee7a t\u1ec7p tin thay \u0111\u1ed5i, h\u00e3y thay \u0111\u1ed5i t\u00ean t\u1ec7p tin ho\u1eb7c c\u00e1c tham s\u1ed1 truy v\u1ea5n; \u0111i\u1ec1u n\u00e0y s\u1ebd khi\u1ebfn ng\u01b0\u1eddi d\u00f9ng y\u00eau c\u1ea7u m\u1ed9t URL ho\u00e0n to\u00e0n m\u1edbi, t\u1eeb \u0111\u00f3 t\u1ef1 \u0111\u1ed9ng tr\u00e1nh s\u1eed d\u1ee5ng c\u00e1c b\u1ea3n nh\u1edb \u0111\u1ec7m (cache) c<\/p>\n\n\n\n

CDN (Content Delivery Network) l\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o an ninh n\u1ed9i dung?<\/h3>\n\n\n\n

CDN s\u1eed d\u1ee5ng nhi\u1ec1u c\u01a1 ch\u1ebf kh\u00e1c nhau \u0111\u1ec3 b\u1ea3o v\u1ec7 an to\u00e0n n\u1ed9i dung. V\u1ec1 m\u1eb7t an to\u00e0n truy\u1ec1n d\u1eef li\u1ec7u, CDN h\u1ed7 tr\u1ee3 giao th\u1ee9c HTTPS m\u1ed9t c\u00e1ch r\u1ed9ng r\u00e3i, gi\u00fap m\u00e3 h\u00f3a d\u1eef li\u1ec7u trong qu\u00e1 tr\u00ecnh truy\u1ec1n t\u1ea3i. V\u1ec1 m\u1eb7t ki\u1ec3m so\u00e1t truy c\u1eadp, CDN cung c\u1ea5p c\u00e1c t\u00ednh n\u0103ng nh\u01b0 ki\u1ec3m so\u00e1t \u0111\u01b0\u1eddng d\u1eabn truy c\u1eadp (Referer), danh s\u00e1ch IP \u0111\u01b0\u1ee3c ph\u00e9p\/tr\u00e1nh (IP allowlist\/blocklist), v\u00e0 x\u00e1c th\u1ef1c b\u1eb1ng Token, nh\u1eb1m ng\u0103n ch\u1eb7n vi\u1ec7c s\u1eed d\u1ee5ng tr\u00e1i ph\u00e9p c\u00e1c t\u00e0i nguy\u00ean.<\/p>\n\n\n\n

\u0110\u1ed1i v\u1edbi nh\u1eefng y\u00eau c\u1ea7u b\u1ea3o m\u1eadt \u1edf c\u1ea5p \u0111\u1ed9 cao h\u01a1n, c\u00e1c d\u1ecbch v\u1ee5 CDN th\u01b0\u1eddng t\u00edch h\u1ee3p ch\u1ee9c n\u0103ng t\u01b0\u1eddng l\u1eeda \u1ee9ng d\u1ee5ng web (Web Application Firewall \u2013 WAF), gi\u00fap b\u1ea3o v\u1ec7 trang web kh\u1ecfi c\u00e1c lo\u1ea1i t\u1ea5n c\u00f4ng m\u1ea1ng ph\u1ed5 bi\u1ebfn nh\u01b0 DDoS, x\u00e2m nh\u1eadp qua SQL (SQL Injection), v\u00e0 t\u1ea5n c\u00f4ng t\u1eeb ch\u1ed1i d\u1ecbch v\u1ee5 (Cross-Site Attacks \u2013 XSS), t\u1eeb \u0111\u00f3 t\u1ea1o ra m\u1ed9t l\u1edbp b\u1ea3o v\u1ec7 cho m\u00e1y ch\u1ee7 ngu\u1ed3n (source<\/p>\n\n\n\n

Ngo\u00e0i vi\u1ec7c c\u00e0i \u0111\u1eb7t v\u00e0 thi\u1ebft l\u1eadp CDN, c\u00e1c m\u00e1y ch\u1ee7 ngu\u1ed3n c\u00f2n c\u1ea7n \u0111\u01b0\u1ee3c t\u1ed1i \u01b0u h\u00f3a th\u00eam nh\u1eefng kh\u00eda c\u1ea1nh sau \u0111\u1ec3 t\u0103ng hi\u1ec7u su\u1ea5t v\u00e0 kh\u1ea3 n\u0103ng ph\u1ee5c v\u1ee5 ng\u01b0\u1eddi d\u00f9ng:<\/h3>\n\n\n\n

Ngay c\u1ea3 khi s\u1eed d\u1ee5ng CDN (Content Delivery Network), vi\u1ec7c t\u1ed1i \u01b0u h\u00f3a m\u00e1y ch\u1ee7 ngu\u1ed3n v\u1eabn r\u1ea5t quan tr\u1ecdng. \u0110\u1ea7u ti\u00ean, c\u1ea7n ph\u1ea3i c\u1ea5u h\u00ecnh \u0111\u00fang c\u00e1c ti\u00eau \u0111\u1ec1 HTTP li\u00ean quan \u0111\u1ebfn vi\u1ec7c l\u01b0u tr\u1eef d\u1eef li\u1ec7u trong b\u1ed9 \u0111\u1ec7m; nh\u1eefng ti\u00eau \u0111\u1ec1 n\u00e0y ch\u00ednh l\u00e0 c\u01a1 s\u1edf \u0111\u1ec3 CDN x\u00e1c \u0111\u1ecbnh c\u00e1ch th\u1ee9c l\u01b0u tr\u1eef v\u00e0 truy xu\u1ea5t d\u1eef li\u1ec7u. Th\u1ee9 hai, c\u1ea7n \u0111\u1ea3m b\u1ea3o t\u00ednh \u1ed5n \u0111\u1ecbnh v\u00e0 t\u1ed1c \u0111\u1ed9 ph\u1ea3n h\u1ed3i c\u1ee7a ch\u00ednh m\u00e1y ch\u1ee7 ngu\u1ed3n, b\u1edfi v\u00ec trong tr\u01b0\u1eddng<\/p>\n\n\n\n

\u0110\u1ec1 ngh\u1ecb b\u1eadt ch\u1ee9c n\u0103ng n\u00e9n d\u1eef li\u1ec7u b\u1eb1ng Gzip ho\u1eb7c Brotli \u0111\u1ec3 gi\u1ea3m l\u01b0\u1ee3ng d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c truy\u1ec1n t\u1eeb m\u00e1y ch\u1ee7 ngu\u1ed3n (origin server). \u0110\u1ed1i v\u1edbi c\u00e1c t\u00e0i nguy\u00ean c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef trong b\u1ed9 \u0111\u1ec7m (cache), b\u1ea1n n\u00ean \u0111\u1eb7t ch\u00fang \u1edf m\u1ed9t t\u00ean mi\u1ec1n ho\u1eb7c \u0111\u01b0\u1eddng d\u1eabn ri\u00eang bi\u1ec7t \u0111\u1ec3 d\u1ec5 d\u00e0ng qu\u1ea3n l\u00fd c\u00e1c ch\u00ednh s\u00e1ch CDN (Content Delivery Network). \u0110\u1ed3ng th\u1eddi, theo d\u00f5i l\u01b0u l\u01b0\u1ee3ng v\u00e0 t\u1ef7 l\u1ec7 truy c\u1eadp t\u1eeb m\u00e1y ch\u1ee7 ngu\u1ed3n th\u00f4ng qua CDN l\u00e0 nh\u1eefng ch\u1ec9 s\u1ed1 quan tr\u1ecdng \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 hi\u1ec7u qu\u1ea3 c\u1ee7a CDN v\u00e0 t\u1ea3i c\u00f4ng su\u1ea5t c\u1ee7a m\u00e1y ch\u1ee7 ngu\u1ed3n.<\/p>","protected":false},"excerpt":{"rendered":"

B\u00e0i vi\u1ebft n\u00e0y ph\u00e2n t\u00edch m\u1ed9t c\u00e1ch h\u1ec7 th\u1ed1ng nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u00f4ng ngh\u1ec7 t\u0103ng t\u1ed1c CDN (Content Delivery Network). B\u1eaft \u0111\u1ea7u t\u1eeb ki\u1ebfn tr\u00fac c\u1ed1t l\u00f5i v\u00e0 c\u01a1 ch\u1ebf ph\u00e2n ph\u1ed1i th\u00f4ng tin th\u00f4ng minh th\u00f4ng qua DNS (Domain Name System), b\u00e0i vi\u1ebft m\u00f4 t\u1ea3 chi ti\u1ebft c\u00e1ch c\u00e1c y\u00eau c\u1ea7u \u0111\u01b0\u1ee3c \u0111\u1ecbnh h\u01b0\u1edbng \u0111\u1ebfn n\u00fat c\u1ea1nh (edge node) ph\u00f9 h\u1ee3p nh\u1ea5t. \u0110\u1ed3ng th\u1eddi, b\u00e0i vi\u1ebft c\u0169ng ph\u00e2n t\u00edch s\u00e2u r\u1ed9ng c\u00e1c tr\u01b0\u1eddng h\u1ee3p truy c\u1eadp d\u1eef li\u1ec7u t\u1eeb b\u1ed9 nh\u1edb \u0111\u1ec7m (cache hit), qu\u00e1 tr\u00ecnh truy xu\u1ea5t d\u1eef li\u1ec7u t\u1eeb ngu\u1ed3n g\u1ed1c (origin pull), c\u0169ng nh\u01b0 c\u00e1c chi\u1ebfn l\u01b0\u1ee3c l\u01b0u tr\u1eef d\u1eef li\u1ec7u d\u1ef1a tr\u00ean th\u00f4ng tin trong ti\u00eau \u0111\u1ec1 HTTP (HTTP headers). T\u1ea5t c\u1ea3 nh\u1eef<\/p>","protected":false},"author":7,"featured_media":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"tags":[385,398,359,361,520],"knowledge_category":[278],"class_list":["post-12375533","knowledge_post","type-knowledge_post","status-publish","hentry","tag-cdn-acceleration","tag-dns-resolution","tag-content-delivery-network","tag-cache-strategy","tag-network-architecture","knowledge_category-cdn"],"acf":{"site_seo_keywords":"CDN\u52a0\u901f\u539f\u7406,DNS\u89e3\u6790,\u7f13\u5b58\u7b56\u7565,\u5185\u5bb9\u5206\u53d1\u7f51\u7edc,\u8fb9\u7f18\u8282\u70b9,\u56de\u6e90\u673a\u5236,\u667a\u80fd\u8c03\u5ea6,HTTP\u7f13\u5b58\u63a7\u5236"},"_links":{"self":[{"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/knowledge_posts\/12375533","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/knowledge_posts"}],"about":[{"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/types\/knowledge_post"}],"author":[{"embeddable":true,"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/users\/7"}],"version-history":[{"count":0,"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/knowledge_posts\/12375533\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/media?parent=12375533"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/tags?post=12375533"},{"taxonomy":"knowledge_category","embeddable":true,"href":"https:\/\/www.likacloud.com\/vi\/wp-json\/wp\/v2\/knowledge_category?post=12375533"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}