{"id":1986,"date":"2012-11-22T11:49:58","date_gmt":"2012-11-22T04:49:58","guid":{"rendered":"http:\/\/snt.com.vn\/blog\/?p=1986"},"modified":"2012-11-22T11:49:58","modified_gmt":"2012-11-22T04:49:58","slug":"cap-xo%e1%ba%afn-doitwisted-pair","status":"publish","type":"post","link":"https:\/\/snt.com.vn\/blog\/cap-xo%e1%ba%afn-doitwisted-pair\/","title":{"rendered":"C\u00e1p xo\u1eafn \u0111\u00f4i(Twisted pair)"},"content":{"rendered":"

\"\"N\u0103m 1881 <\/strong>Alexander Graham Bell<\/strong> l\u00e0 ng\u01b0\u1eddi \u0111\u1ea7u ti\u00ean \u0111\u01b0a c\u00e1p xo\u1eafn \u0111\u00f4i v\u00e0o s\u1eed d\u1ee5ng trong d\u1ecbch v\u1ee5 \u0111i\u1ec7n tho\u1ea1i.V\u00e0 \u0111\u1ebfn n\u0103m 1900,lo\u1ea1i c\u00e1p n\u00e0y \u0111\u00e3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng ph\u1ed5 bi\u1ebfn,r\u1ed9ng r\u00e3i tr\u00ean to\u00e0n n\u01b0\u1edbc M\u0129.Ng\u00e0y nay h\u00e0ng tri\u1ec7u Km c\u00e1p xo\u1eafn \u0111\u00f4i \u0111ang \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng b\u00ean ngo\u00e0i b\u1edfi c\u00e1c c\u00f4ng ty \u0111i\u1ec7n tho\u1ea1i ,ph\u1ee5c v\u1ee5 cho truy\u1ec1n t\u1ea3i \u00e2m thanh.V\u00e0 ph\u1ea7n l\u1edbn c\u00e1c m\u1ea1ng th\u00f4ng tin,Internet c\u0169ng s\u1eed d\u1ee5ng lo\u1ea1i c\u00e1p n\u00e0y. <\/strong><\/em><\/span><\/p>\n

Ch\u1eb3ng bao l\u00e2u sau ph\u00e1t minh ra \u0111i\u1ec7n tho\u1ea1i,c\u00e1c \u0111\u01b0\u1eddng d\u00e2y c\u00e1p \u0111\u00e3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong c\u00f4ng ngh\u1ec7 truy\u1ec1n t\u1ea3i .Hai d\u00e2y \u0111\u01b0\u1ee3c c\u0103ng ra \u1edf 2 ph\u00eda c\u1ee7a thanh ch\u00e9o tr\u00ean c\u00e1c c\u1ef1c, truy\u1ec1n t\u1ea3i chung tuy\u1ebfn \u0111\u01b0\u1eddng v\u1edbi d\u00e2y \u0111i\u1ec7n.Ban \u0111\u1ea7u c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u nh\u1eadn ra r\u1eb1ng d\u00e2y \u0111i\u1ec7n \u0111\u00e3 l\u00e0m gi\u1ea3m \u0111i kho\u1ea3ng c\u00e1ch truy\u1ec1n t\u1ea3i c\u1ee7a t\u00edn hi\u1ec7u \u0111i\u1ec7n tho\u1ea1i.V\u00e0 m\u1ed9t gi\u1ea3i ph\u00e1p m\u1edbi \u0111\u01b0\u1ee3c \u0111\u01b0a ra g\u1ecdi l\u00e0 s\u1ef1 chuy\u1ec3n v\u1ecb d\u00e2y,\u0111\u1ec3 gi\u1ea3m b\u1edbt s\u1ef1 giao thoa,t\u1ea1i c\u00e1c c\u1ef1c, 2 d\u00e2y l\u1ea1i \u0111\u01b0\u1ee3c v\u1eaft ch\u00e9o qua nhau.Nh\u01b0 v\u1eady m\u1ed7i d\u00e2y s\u1ebd ch\u1ecbu \u00edt \u1ea3nh h\u01b0\u1edfng c\u1ee7a s\u1ef1 ph\u00e1t x\u1ea1 nhi\u1ec5u \u0111i\u1ec7n t\u1eeb t\u1eeb d\u00f2ng \u0111i\u1ec7n h\u01a1n.Ng\u00e0y nay ,nh\u1eefng \u0111\u01b0\u1eddng d\u00e2y tr\u1ea7n v\u1edbi s\u1ef1 chuy\u1ec3n v\u1ecb tu\u1ea7n ho\u00e0n nh\u01b0 v\u1eady v\u1eabn c\u00f3 th\u1ec3 c\u00f2n \u0111\u01b0\u1ee3c b\u1eaft g\u1eb7p \u1edf c\u00e1c v\u00f9ng n\u00f4ng th\u00f4n.\u0110i\u1ec1u n\u00e0y \u0111\u1ea1i di\u1ec7n cho m\u1ed9t s\u1ef1 thi h\u00e0nh s\u1edbm c\u1ee7a s\u1ef1 xo\u1eafn v\u1edbi nh\u1ecbp xo\u1eafn l\u00e0 4 l\u1ea7n tr\u00ean 1 Km.D\u1ef1a tr\u00ean nh\u1eefng th\u00e0nh qu\u1ea3 nghi\u00ean c\u1ee9u \u0111\u00f3,n\u0103m 1881,Alexander Graham Bell(nh\u00e0 b\u00e1c h\u1ecdc Th\u1ee5y s\u0129 ng\u01b0\u1eddi \u0111\u00e3 ph\u00e1t minh ra chi\u1ebfc m\u00e1y \u0111i\u1ec7n tho\u1ea1i v\u00e0o n\u0103m 1876) \u0111\u00e3 \u0111\u01b0a c\u00e1p xo\u1eafn \u0111\u00f4i v\u00e0o s\u1eed d\u1ee5ng cho h\u1ec7 th\u1ed1ng \u0111i\u1ec7n tho\u1ea1i c\u1ee7a ch\u00ednh c\u00f4ng ty truy\u1ec1n th\u00f4ng Bell c\u1ee7a \u00f4ng.<\/span><\/span>
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\n<\/span>C\u00e1p xo\u1eafn \u0111\u00f4i(Twisted pair<\/strong>) l\u00e0 lo\u1ea1i c\u00e1p g\u1ed3m nhi\u1ec1u c\u1eb7p d\u00e2y \u0111\u1ed3ng xo\u1eafn l\u1ea1i v\u1edbi nhau nh\u1eb1m ch\u1ed1ng ph\u00e1t x\u1ea1 nhi\u1ec5u \u0111i\u1ec7n t\u1eeb (Electromagnetic Interference-EMI<\/strong>) t\u1eeb b\u00ean ngo\u00e0i,t\u1eeb s\u1ef1 ph\u00e1t x\u1ea1 c\u1ee7a lo\u1ea1i c\u00e1p\u00a0UTP<\/strong> v\u00e0 s\u1ef1 xuy\u00ean \u00e2m(Crosstalk<\/strong>) gi\u1eefa nh\u1eefng c\u1eb7p c\u00e1p li\u1ec1n k\u1ec1.
\n(Trong th\u00f4ng tin v\u00f4 tuy\u1ebfn, s\u1ef1 xuy\u00ean \u00e2m th\u01b0\u1eddng \u0111\u01b0\u1ee3c bi\u1ec3u th\u1ecb giao thoa \u0111\u1ed3ng k\u00eanh, v\u00e0 li\u00ean quan \u0111\u1ebfn giao thoa k\u00eanh- k\u1ec1 b\u00ean. )
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[SIZE=4][I] C\u00e1p xo\u1eafn c\u00f3 th\u1ec3 l\u00e0m gi\u1ea3m nhi\u1ec5u v\u00ec hai d\u00e2y ch\u1ec9 truy\u1ec1n m\u1ed9t \u0111\u01b0\u1eddng d\u1eef li\u1ec7u, bi\u1ec5u di\u1ec5n b\u1eb1ng hi\u1ec7u \u0111i\u1ec7n th\u1ebf gi\u1eefa hai d\u00e2y n\u00e0y. Khi nhi\u1ec5u \u0111\u00e1nh v\u00e0o, hai d\u00e2y xo\u1eafn v\u00e0o nhau n\u00ean s\u1ebd xem nh\u01b0 b\u1ecb nhi\u1ec5u gi\u1ed1ng nhau, c\u00f9ng t\u0103ng ho\u1eb7c c\u00f9ng gi\u1ea3m m\u1ed9t \u0111i\u1ec7n \u00e1p nh\u1ea5t \u0111\u1ecbnh.Hi\u1ec7u \u0111i\u1ec7n th\u1ebf gi\u1eefa hai d\u00e2y v\u1eabn gi\u1eef nguy\u00ean n\u00ean d\u1eef li\u1ec7u truy\u1ec1n v\u1eabn \u0111\u00fang.
\nDo gi\u00e1 th\u00e0nh th\u1ea5p n\u00ean c\u00e1p xo\u1eafn \u0111\u01b0\u1ee3c d\u00f9ng r\u1ea5t r\u1ed9ng r\u00e3i \u0111\u1eb7c bi\u1ec7t l\u00e0 l\u00e0m c\u00e1p \u0111i\u1ec7n tho\u1ea1i v\u00e0 s\u1eed d\u1ee5ng cho c\u00e1c lo\u1ea1i m\u00e1y t\u00ednh trong c\u00f4ng ngh\u1ec7 truy\u1ec1n th\u00f4ng Internet.<\/span>C\u00e1c lo\u1ea1i c\u00e1p x\u1eafn \u0111\u00f4i c\u00f3 t\u1ed1c \u0111\u1ed9 truy\u1ec1n t\u1ed1i \u0111a c\u00f3 th\u1ec3 l\u00ean \u0111\u1ebfn h\u00e0ng ch\u1ee5c Gigabit\/gi\u00e2y (Gbps) v\u1edbi t\u1ea7n s\u1ed1 dao \u0111\u1ed9ng c\u00f3 th\u1ec3 \u0111\u1ea1t t\u1edbi 600MHz<\/span>.<\/p>\n

C\u00f3 hai lo\u1ea1i c\u00e1p xo\u1eafn \u0111\u00f4i \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i trong\u00a0LAN<\/strong> l\u00e0: lo\u1ea1i c\u00f3 v\u1ecf b\u1ecdc ch\u1ed1ng nhi\u1ec5u(STP<\/strong>) v\u00e0 lo\u1ea1i kh\u00f4ng c\u00f3 v\u1ecf b\u1ecdc ch\u1ed1ng nhi\u1ec5u(UTP<\/strong>).<\/span>
\nI- C\u00e1p xo\u1eafn \u0111\u00f4i kh\u00f4ng c\u00f3 v\u1ecf b\u1ecdc ch\u1ed1ng nhi\u1ec5u UTP(Unshielded Twisted Pair)<\/strong><\/span><\/p>\n

UTP<\/strong> c\u00e1p kh\u00f4ng c\u00f3 v\u1ecf b\u1ecdc ch\u1ed1ng nhi\u1ec5u.B\u00f9 l\u1ea1i n\u00f3 c\u00f3 t\u00ednh linh ho\u1ea1t v\u00e0 \u0111\u1ed9 b\u1ec1n cao.G\u1ed3m nhi\u1ec1u c\u1eb7p xo\u1eafn nh\u01b0 c\u00e1p\u00a0STP<\/strong> nh\u01b0ng kh\u00f4ng c\u00f3 l\u1edbp v\u1ecf \u0111\u1ed3ng ch\u1ed1ng nhi\u1ec5u. C\u00e1p xo\u1eafn \u0111\u00f4i tr\u1ea7n s\u1eed d\u1ee5ng chu\u1ea9n 10BaseT ho\u1eb7c 100BaseT. Do gi\u00e1 th\u00e0nh r\u1ebb n\u00ean \u0111\u00e3 nhanh ch\u00f3ng tr\u1edf th\u00e0nh lo\u1ea1i c\u00e1p m\u1ea1ng c\u1ee5c b\u1ed9 \u0111\u01b0\u1ee3c \u01b0u chu\u1ed9ng nh\u1ea5t. \u0110\u1ed9 d\u00e0i t\u1ed1i \u0111a c\u1ee7a m\u1ed9t \u0111o\u1ea1n c\u00e1p l\u00e0 100 m\u00e9t. Kh\u00f4ng c\u00f3 v\u1ecf b\u1ecdc ch\u1ed1ng nhi\u1ec5u n\u00ean d\u1ec5 b\u1ecb nhi\u1ec5u khi \u0111\u1eb7t g\u1ea7n c\u00e1c thi\u1ebft b\u1ecb v\u00e0 c\u00e1p kh\u00e1c do \u0111\u00f3 th\u00f4ng th\u01b0\u1eddng d\u00f9ng \u0111\u1ec3 \u0111i d\u00e2y trong nh\u00e0. \u0110\u1ea7u n\u1ed1i d\u00f9ng \u0111\u1ea7u RJ-45. C\u00e1p\u00a0UTP<\/strong> c\u00f3 5 lo\u1ea1i:<\/span><\/p>\n


\nLo\u1ea1i 1: truy\u1ec1n \u00e2m thanh, t\u1ed1c \u0111\u1ed9 <4Mbps<\/span>
\nLo\u1ea1i 2: c\u00e1p n\u00e0y g\u1ed3m 4 d\u00e2y xo\u1eafn \u0111\u00f4i, t\u1ed1c \u0111\u1ed9 4Mbps<\/span>
\nLo\u1ea1i 3: truy\u1ec1n d\u1eef li\u1ec7u v\u1edbi t\u1ed1c \u0111\u1ed9 l\u00ean \u0111\u1ebfn 10 Mbps. C\u00e1p n\u00e0y g\u1ed3m 4 d\u00e2y xo\u1eafn \u0111\u00f4i v\u1edbi 3 m\u1eaft xo\u1eafn tr\u00ean m\u1ed7i foot.<\/span>
\nLo\u1ea1i 4: truy\u1ec1n d\u1eef li\u1ec7u, 4 c\u1eb7p xo\u1eafn \u0111\u00f4i, t\u1ed1c \u0111\u1ed9 \u0111\u1ea1t \u0111\u01b0\u1ee3c 16 Mbps<\/span>
\nLo\u1ea1i 5: truy\u1ec1n d\u1eef li\u1ec7u, 4 c\u1eb7p xo\u1eafn \u0111\u00f4i, t\u1ed1c \u0111\u1ed9 100Mbp<\/span><\/em><\/span><\/p>\n

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\nL\u00e0 m\u1ed9t d\u1ea1ng c\u00e1p xo\u1eafn \u0111\u00f4i,c\u00e1p<\/em> UTP<\/em><\/strong> \u0111\u00e3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng h\u01a1n 100 n\u0103m b\u1edfi c\u00e1c h\u1ec7 th\u1ed1ng \u0111i\u1ec7n tho\u1ea1i,m\u1ea1ng m\u00e1y t\u00ednh.N\u00f3 c\u00f2n c\u00f3 m\u1ed9t t\u00ean g\u1ecdi kh\u00e1c l\u00e0 c\u00e1p <\/em>Ethernet<\/em><\/strong>,theo t\u00ean c\u1ee7a m\u1ea1ng <\/em>Erthernet<\/em><\/strong>,lo\u1ea1i m\u1ea1ng s\u1eed d\u1ee5ng c\u00e1p <\/em>UTP<\/em><\/strong> nhi\u1ec1u nh\u1ea5t tr\u00ean th\u1ebf gi\u1edbi.<\/em>V\u00e0 t\u00ednh \u0111\u1ebfn hi\u1ec7n nay th\u00ec c\u00e1p UTP \u0111\u01b0\u1ee3c ph\u00e2n lo\u1ea1i l\u00e0m 7 lo\u1ea1i, t\u1eeb cat 1 c\u00f3 t\u1ed1c \u0111\u1ed9 v\u00e0 kh\u1ea3 n\u0103ng ch\u1ed1ng nhi\u1ec5u th\u1ea5p nh\u1ea5t th\u01b0\u1eddng d\u00f9ng \u0111\u1ec3 truy\u1ec1n t\u00edn hi\u1ec7u tho\u1ea1i trong ng\u00e0nh b\u01b0u \u0111i\u1ec7n \u0111\u1ebfn cat 7 c\u00f3 t\u1ed1c \u0111\u1ed9 v\u00e0 kh\u1ea3 n\u0103ng ch\u1ed1ng nhi\u1ec5u cao nh\u1ea5t.<\/p>\n

<\/em><\/span>II-C\u00e1p xo\u1eafn \u0111\u00f4i c\u00f3 v\u1ecf b\u1ecdc ch\u1ed1ng nhi\u1ec5u STP(Shielded Twisted Pair)<\/strong><\/span><\/p>\n

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G\u1ed3m nhi\u1ec1u c\u1eb7p xo\u1eafn \u0111\u01b0\u1ee3c ph\u1ee7 b\u00ean ngo\u00e0i m\u1ed9t l\u1edbp v\u1ecf l\u00e0m b\u1eb1ng d\u00e2y \u0111\u1ed3ng b\u1ec7n. L\u1edbp v\u1ecf n\u00e0y c\u00f3 t\u00e1c d\u1ee5ng ch\u1ed1ng EMI t\u1eeb ngo\u00e0i v\u00e0 ch\u1ed1ng ph\u00e1t x\u1ea1 nhi\u1ec5u b\u00ean trong. L\u1edbp v\u1ecf b\u1ecdc ch\u1ed1ng nhi\u1ec5u n\u00e0y \u0111\u01b0\u1ee3c n\u1ed1i \u0111\u1ea5t \u0111\u1ec3 tho\u00e1t nhi\u1ec5u. C\u00e1p xo\u1eafn \u0111\u00f4i c\u00f3 b\u1ecdc \u00edt b\u1ecb t\u00e1c \u0111\u1ed9ng b\u1edfi nhi\u1ec5u \u0111i\u1ec7n v\u00e0 c\u00f3 t\u1ed1c \u0111\u1ed9 truy\u1ec1n qua kho\u1ea3ng c\u00e1ch xa cao h\u01a1n c\u00e1p xo\u1eafn \u0111\u00f4i tr\u1ea7n.<\/p>\n

\n– Chi ph\u00ed: \u0111\u1eaft ti\u1ec1n h\u01a1n Thinnet v\u00e0 UTP nh\u01b0ng l\u1ea1i r\u1ebb ti\u1ec1n h\u01a1n Thicknet v\u00e0 c\u00e1p quang.\u00a0
\n– T\u1ed1c \u0111\u1ed9: t\u1ed1c \u0111\u1ed9 l\u00fd thuy\u1ebft 500Mbps, th\u1ef1c t\u1ebf kho\u1ea3ng 155Mbps, v\u1edbi \u0111\u01b0\u1eddng ch\u1ea1y 100m. T\u1ed1c \u0111\u1ed9 ph\u1ed5 bi\u1ebfn 16Mbps (Token Ring).\u00a0
\n– \u0110\u1ed9 suy d\u1ea7n: t\u00edn hi\u1ec7u y\u1ebfu d\u1ea7n n\u1ebfu c\u00e1p c\u00e0ng d\u00e0i, th\u00f4ng th\u01b0\u1eddng ng\u1eafn h\u01a1n 100m.\u00a0
\n– \u0110\u1ea7u n\u1ed1i: STP s\u1eed d\u1ee5ng \u0111\u1ea7u n\u1ed1i DIN (DB \u20139).<\/p>\n

\n<\/span><\/em><\/span>Ngo\u00e0i 2 d\u1ea1ng c\u00e1p tr\u00ean, c\u00e1p xo\u1eafn \u0111\u00f4i c\u00f2n m\u1ed9t d\u1ea1ng n\u1eefa l\u00e0 FTP(Foiled Twisted Pair).FTP l\u00e0 lo\u1ea1i c\u00e1p lai t\u1ea1o gi\u1eefa c\u00e1p UTP v\u00e0 STP, n\u00f3 h\u1ed7 tr\u1ee3 chi\u1ec1u d\u00e0i t\u1ed1i \u0111a 100m<\/strong>. <\/strong><\/em><\/span><\/p>\n

<\/span>III-\u00cdch l\u1ee3i v\u00e0 h\u1ea1n ch\u1ebf:<\/strong><\/span>
\n1)\u00cdch l\u1ee3i<\/strong>
\n<\/em><\/span><\/p>\n

    \n
  • L\u00e0 lo\u1ea1i c\u00e1p m\u1ecfng, m\u1ec1m d\u1ebbo n\u00ean d\u1ec5 d\u00e0ng \u0111\u1ec3 k\u00e9o d\u00e0i th\u00e0nh d\u00e2y gi\u1eefa nh\u1eefng t\u01b0\u1eddng.<\/span><\/em><\/span><\/li>\n
  • C\u00e1p UTP nh\u1ecf, n\u00f3 kh\u00f4ng nhanh \u0111\u1ed5 \u0111\u1ea7y tr\u00e0n nh\u1eefng \u1ed1ng n\u1ed1i d\u00e2y.<\/span><\/em><\/span><\/li>\n
  • UTP chi ph\u00ed \u00edt h\u01a1n so v\u1edbi m\u1ecdi c\u00e1p ki\u1ec3u LAN kh\u00e1c<\/span><\/em><\/span><\/li>\n<\/ul>\n

    \n2)<\/strong><\/span>H\u1ea1n ch\u1ebf<\/strong><\/span>:
    \n<\/strong><\/span>T\u00ednh c\u1ea3m \u1ee9ng c\u1ee7a c\u00e1p xo\u1eafn t\u1edbi ph\u00e1t x\u1ea1 nhi\u1ec5u \u0111i\u1ec7n t\u1eeb ph\u1ee5 thu\u1ed9c nhi\u1ec1u v\u00e0o nh\u1eefng s\u01a1 \u0111\u1ed3 Xo\u1eafn c\u1eb7p (th\u00f4ng th\u01b0\u1eddng \u0111\u01b0\u1ee3c c\u1ea5p b\u1eb1ng s\u00e1ng ch\u1ebf b\u1edfi nh\u1eefng nh\u00e0 s\u1ea3n xu\u1ea5t) v\u00e0 kh\u00f4ng \u0111\u01b0\u1ee3c s\u1ee9t m\u1ebb trong th\u1eddi gian s\u1ef1 c\u00e0i \u0111\u1eb7t. Do \u0111\u00f3, nh\u1eefng c\u00e1p xo\u1eafn \u0111\u00f4i th\u00f4ng th\u01b0\u1eddng c\u00f3 nh\u1eefng y\u00eau c\u1ea7u kh\u00f3 kh\u0103n cho vi\u1ec7c s\u1eafp \u0111\u1eb7t b\u00e1n k\u00ednh u\u1ed1ng cong c\u1ef1c ti\u1ec3u ho\u1eb7c c\u1ef1c \u0111\u1ea1i. T\u00ednh d\u1ec5 v\u1ee1 t\u01b0\u01a1ng \u0111\u1ed1i n\u00e0y c\u1ee7a nh\u1eefng c\u00e1p xo\u1eafn \u0111\u00f4i l\u00e0m cho vi\u1ec7c th\u1ef1c hi\u1ec7n vi\u1ec7c c\u00e0i \u0111\u1eb7t tr\u1edf th\u00e0nh m\u1ed9t y\u1ebfu t\u1ed1 quan tr\u1ecdng \u0111\u1ea3m b\u1ea3o cho s\u1ef1 ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u00e1p.<\/span><\/em><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

    N\u0103m 1881 Alexander Graham Bell l\u00e0 ng\u01b0\u1eddi \u0111\u1ea7u ti\u00ean \u0111\u01b0a c\u00e1p xo\u1eafn \u0111\u00f4i v\u00e0o s\u1eed d\u1ee5ng trong d\u1ecbch v\u1ee5 \u0111i\u1ec7n<\/p>\n","protected":false},"author":9,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11,1],"tags":[],"yoast_head":"\nC\u00e1p xo\u1eafn \u0111\u00f4i(Twisted pair) - Blog SNT - C\u00f4ng Ty TNHH Si\u00eau Nh\u1eadt Thanh - Sao Nhanh Th\u1ebf<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/snt.com.vn\/blog\/cap-xo\u1eafn-doitwisted-pair\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"C\u00e1p xo\u1eafn \u0111\u00f4i(Twisted pair) - Blog SNT - C\u00f4ng Ty TNHH Si\u00eau Nh\u1eadt Thanh - 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