{"id":10326,"date":"2021-11-21T19:49:45","date_gmt":"2021-11-21T12:49:45","guid":{"rendered":"https:\/\/www.vietlearn.org\/post\/?p=10326"},"modified":"2021-11-21T20:11:22","modified_gmt":"2021-11-21T13:11:22","slug":"modem-va-card-mang-co-gi-khac-nhau","status":"publish","type":"post","link":"https:\/\/www.vietlearn.org\/kien-thuc\/modem-va-card-mang-co-gi-khac-nhau\/","title":{"rendered":"M\u00f4\u0111em v\u00e0 card m\u1ea1ng c\u00f3 g\u00ec kh\u00e1c nhau?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Ngay t\u1eeb nh\u1eefng n\u0103m 60 th\u1ebf k\u1ec9 XX ng\u01b0\u1eddi ta \u0111\u00e3 ngh\u0129 c\u00e1ch s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n tho\u1ea1i b\u00ecnh th\u01b0\u1eddng \u0111\u1ec3 k\u1ebft n\u1ed1i nh\u1eefng m\u00e1y t\u00ednh \u0111\u1eb7t c\u00e1ch xa nhau, khi\u1ebfn ch\u00fang ta c\u00f3 th\u1ec3 truy\u1ec1n d\u1eef li\u1ec7u cho nhau. Th\u1ebf nh\u01b0ng \u0111\u01b0\u1eddng \u0111i\u1ec7n tho\u1ea1i ch\u1ec9 c\u00f3 th\u1ec3 truy\u1ec1n \u00e2m thanh &#8211; lo\u1ea1i t\u00edn hi\u1ec7u t\u01b0\u01a1ng t\u1ef1, c\u00f2n m\u00e1y t\u00ednh th\u00ec l\u1ea1i c\u1ea7n truy\u1ec1n m\u1ed9t d\u00e3y t\u00edn hi\u1ec7u s\u1ed1 0 v\u00e0 1 c\u1ee7a h\u1ec7 nh\u1ecb ph\u00e2n. B\u1edfi v\u1eady, c\u1ea7n ph\u1ea3i c\u00f3 m\u1ed9t thi\u1ebft b\u1ecb c\u00f3 th\u1ec3 truy\u1ec1n t\u00edn hi\u1ec7u s\u1ed1 th\u00e0nh t\u00edn hi\u1ec7u t\u01b0\u01a1ng t\u1ef1 \u0111\u1ec3 c\u00f3 th\u1ec3 truy\u1ec1n t\u1ea3i tr\u00ean \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n tho\u1ea1i. Do v\u1eady m\u00e0 m\u00f4\u0111em \u0111\u00e3 ra \u0111\u1eddi. M\u00f4\u0111em \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng th\u00e0nh c\u1eb7p, hai m\u00e1y t\u00ednh mu\u1ed1n k\u1ebft n\u1ed1i v\u1edbi nhau th\u00ec ph\u1ea3i c\u00f3 n\u00f3 n\u1ed1i v\u1edbi \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n tho\u1ea1i. Tr\u00ean th\u1ef1c t\u1ebf th\u00ec m\u00f4\u0111em \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh b\u1edfi hai thi\u1ebft b\u1ecb \u0111i\u1ec1u ch\u1ebf v\u00e0 gi\u1ea3i \u0111i\u1ec1u ch\u1ebf. B\u1ed9 \u0111i\u1ec1u ch\u1ebf (bi\u1ebfn \u0111i\u1ec7u) c\u00f3 nhi\u1ec7m v\u1ee5 chuy\u1ec3n t\u00edn hi\u1ec7u s\u1ed1 c\u1ea7n ph\u00e1t \u0111i th\u00e0nh t\u00edn hi\u1ec7u t\u01b0\u01a1ng t\u1ef1, c\u00f2n b\u1ed9 gi\u1ea3i \u0111i\u1ec1u ch\u1ebf (gi\u1ea3i \u0111i\u1ec1u) th\u00ec l\u1ea1i chuy\u1ec3n t\u00edn hi\u1ec7u t\u01b0\u01a1ng t\u1ef1 \u0111\u00e3 thu \u0111\u01b0\u1ee3c th\u00e0nh t\u00edn hi\u1ec7u s\u1ed1 (ho\u00e0n nguy\u00ean). T\u1eeb ti\u1ebfng Anh MODEM l\u00e0 gh\u00e9p m\u1ea5y ch\u1eef \u0111\u1ea7u c\u1ee7a hai t\u1eeb ch\u1ec9 b\u1ed9 \u0111i\u1ec1u ch\u1ebf modulator v\u00e0 gi\u1ea3i \u0111i\u1ec1u demodulator. Ngo\u00e0i ra, c\u00f3 nh\u1eefng m\u00f4\u0111em c\u00f2n c\u00f3 ch\u1ee9c n\u0103ng n\u00e9n, ki\u1ec3m tra sai s\u00f3t v\u00e0 s\u1eeda ch\u1eefa sai s\u00f3t. Nh\u1eefng m\u00f4\u0111em \u0111\u1ea7u ti\u00ean ch\u1ec9 l\u00e0 thi\u1ebft b\u1ecb \u0111\u01a1n \u0111\u1ed9c, n\u00f3 \u0111\u01b0\u1ee3c g\u1eafn v\u1edbi c\u1ed5ng truy\u1ec1n th\u00f4ng tu\u1ea7n t\u1ef1. V\u1ec1 sau ng\u01b0\u1eddi ta l\u00e0m m\u00f4\u0111em th\u00e0nh m\u1ed9t t\u1ea5m card, tr\u1ef1c ti\u1ebfp c\u1eafm v\u00e0o khe c\u1ed5ng tuy\u1ebfn c\u1ee7a m\u00e1y t\u00ednh, \u0111\u00f3 l\u00e0 m\u00f4\u0111em ki\u1ec3u l\u1eafp trong. Ngo\u00e0i ra m\u00f4\u0111em c\u00f2n chia ra lo\u1ea1i b\u1ea5m s\u1ed1 (quay s\u1ed1) v\u00e0 chuy\u00ean tuy\u1ebfn. Lo\u1ea1i b\u1ea5m s\u1ed1 s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n tho\u1ea1i hi\u1ec7n c\u00f3, khi n\u1ed1i m\u1ea1ng th\u00ec c\u1ea7n b\u1ea5m s\u1ed1. Lo\u1ea1i chuy\u00ean tuy\u1ebfn l\u00e0 ph\u1ea3i thu\u00ea bao ri\u00eang m\u1ed9t \u0111\u01b0\u1eddng d\u00e2y c\u1ee7a ng\u00e0nh b\u01b0u \u0111i\u1ec7n v\u00e0 k\u1ebft n\u1ed1i c\u1ed1 \u0111\u1ecbnh, kh\u00f4ng c\u1ea7n b\u1ea5m s\u1ed1.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Card m\u1ea1ng l\u00e0 g\u1ecdi t\u1eaft card ti\u1ebfp giao di\u1ec7n. Card m\u1ea1ng c\u00f2n g\u1ecdi l\u00e0 card ph\u1ed1i h\u1ee3p m\u1ea1ng. N\u00f3 l\u00e0 lo\u1ea1i card giao di\u1ec7n \u0111\u01b0a v\u00e0o \u0111\u01b0a ra \u0111\u01b0\u1ee3c g\u1eafn tr\u1ef1c ti\u1ebfp v\u00e0o khe c\u1ed5ng tuy\u1ebfn c\u1ee7a m\u00e1y t\u00ednh. M\u00e1y t\u00ednh s\u1ebd k\u1ebft n\u1ed1i v\u1edbi c\u00e1p m\u1ea1ng th\u00f4ng qua n\u00f3. Card m\u1ea1ng \u0111\u01b0\u1ee3c <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">thi\u1ebft k\u1ebf<\/a> cho m\u1ea1ng x\u00e1c \u0111\u1ecbnh, nh\u1eefng m\u1ea1ng kh\u00e1c nhau c\u00f2n d\u00f9ng card m\u1ea1ng kh\u00e1c nhau. V\u00ed d\u1ee5 d\u00f9ng cho k\u1ebft n\u1ed1i v\u1edbi m\u1ea1ng Ethernet ph\u1ea3i c\u00f3 card m\u1ea1ng Ethernet, d\u00f9ng cho k\u1ebft n\u1ed1i m\u1ea1ng Token-ring (m\u1ea1ng v\u00f2ng) th\u00ec ph\u1ea3i d\u00f9ng card m\u1ea1ng Token, d\u00f9ng \u0111\u1ec3 k\u1ebft n\u1ed1i m\u1ea1ng ATM (ki\u1ec3u truy\u1ec1n t\u1ea3i kh\u00f4ng \u0111\u1ed3ng b\u1ed9- Asynchronous Transfer Mode) l\u00e0 card m\u1ea1ng ATM v.v. D\u00f9 r\u1eb1ng c\u00f9ng m\u1ed9t m\u1ea1ng nh\u01b0ng n\u1ebfu s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng c\u00e1p kh\u00e1c nhau th\u00ec card m\u1ea1ng c\u0169ng ph\u1ea3i kh\u00e1c nhau. V\u00ed d\u1ee5 m\u1ea1ng Ethernet c\u00f3 th\u1ec3 d\u00f9ng c\u00e1p \u0111\u1ed3ng tr\u1ee5c to, c\u00e1p \u0111\u1ed3ng tr\u1ee5c nh\u1ecf v\u00e0 d\u00e2y xo\u1eafn \u0111\u00f4i. Nh\u1eefng card m\u1ea1ng t\u01b0\u01a1ng \u1ee9ng c\u0169ng c\u00f3 c\u00e1i kh\u00e1c nhau. Card m\u1ea1ng c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n nhi\u1ec1u ch\u1ee9c n\u0103ng m\u00e0 m\u1ea1ng c\u1ea7n. V\u1edbi card m\u1ea1ng Ethernet th\u00ec n\u00f3 tr\u01b0\u1edbc h\u1ebft \u0111\u01b0a d\u1eef li\u1ec7u m\u00e0 m\u00e1y t\u00ednh c\u1ea7n truy\u1ec1n \u0111i \u0111\u1ec3 v\u00e0o khu ho\u00e3n xung c\u1ee7a n\u00f3, r\u1ed3i bi\u1ebfn \u0111\u1ed5i s\u1ed1 li\u1ec7u c\u00f3 \u0111\u01a1n v\u1ecb k\u00ed t\u1ef1 th\u00e0nh d\u00e3y h\u1ec7 nh\u1ecb ph\u00e2n, ti\u1ebfp \u0111\u00f3 bi\u1ebfn d\u00e3y s\u1ed1 nh\u1ecb ph\u00e2n th\u00e0nh h\u00ecnh th\u1ee9c m\u1ea1ng c\u00f3 th\u1ec3 ti\u1ebfp nh\u1eadn v\u00e0 ph\u00e1t l\u00ean m\u1ea1ng. \u0110\u1ed3ng th\u1eddi n\u00f3 c\u00f2n xem x\u00e9t m\u1ea1ng c\u00f3 r\u1ed7i kh\u00f4ng, c\u00f3 ph\u00e1t sinh xung \u0111\u1ed9t trong truy\u1ec1n d\u1eabn kh\u00f4ng.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">M\u00f4\u0111em ki\u1ec3u l\u1eafp \u0111\u1eb7t b\u00ean trong l\u00e0 lo\u1ea1i card ph\u1ed1i h\u1ee3p m\u1ea1ng. N\u00f3 k\u1ebft n\u1ed1i m\u1ea1ng di\u1ec7n r\u1ed9ng b\u1eb1ng \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n tho\u1ea1i. Nh\u01b0ng theo t\u1eadp qu\u00e1n, khi n\u00f3i t\u1edbi card m\u1ea1ng th\u00ec ph\u1ea7n l\u1edbn ch\u1ec9 card m\u1ea1ng k\u1ebft n\u1ed1i m\u1ea1ng c\u1ee5c b\u1ed9, nh\u01b0 card m\u1ea1ng Ethernet. Hi\u1ec7n nay c\u00f3 nhi\u1ec1u ng\u01b0\u1eddi g\u1ecdi card m\u1ea1ng ph\u1ed1i h\u1ee3p ISDN d\u00f9ng cho vi\u1ec7c k\u1ebft n\u1ed1i m\u1ea1ng s\u1ed1 nghi\u1ec7p v\u1ee5 t\u1ed5ng h\u1ee3p l\u00e0 ISDN MODEM ho\u1eb7c MODEM s\u1ed1. Th\u1ef1c ra th\u00ec g\u1ecdi nh\u01b0 v\u1eady l\u00e0 kh\u00f4ng ch\u00ednh x\u00e1c, v\u00ec m\u1ea1ng s\u1ed1 nghi\u1ec7p v\u1ee5 t\u1ed5ng h\u1ee3p l\u00e0 m\u1ea1ng s\u1ed1, c\u00f3 th\u1ec3 tr\u1ef1c ti\u1ebfp chuy\u1ec3n t\u1ea3i con s\u1ed1, kh\u00f4ng c\u1ea7n c\u00f3 m\u00f4\u0111em. Th\u1ebf nh\u01b0ng t\u1eeb MODEM ng\u00e0y c\u00e0ng \u0111\u01b0\u1ee3c d\u00f9ng nhi\u1ec1u \u0111\u1ec3 ch\u1ec9 thi\u1ebft b\u1ecb li\u00ean k\u1ebft m\u00e1y t\u00ednh th\u00f4ng qua \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n tho\u1ea1i. B\u1edfi v\u1eady m\u00e0 c\u00e1ch g\u1ecdi n\u00e0y \u0111\u00e3 \u0111\u01b0\u1ee3c \u0111a s\u1ed1 ch\u1ea5p nh\u1eadn.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Trong c\u1ea5u tr\u00fac h\u1ec7 th\u1ed1ng m\u1ea1ng m\u00e1y t\u00ednh, m\u00f4\u0111em v\u00e0 card m\u1ea1ng c\u1ee5c b\u1ed9 \u0111\u1ec1u th\u1ef1c hi\u1ec7n ch\u1ee9c n\u0103ng t\u1ea7ng v\u1eadt l\u00ed, nh\u01b0ng ch\u00fang tr\u00ean th\u1ef1c t\u1ebf l\u00e0 hai thi\u1ebft b\u1ecb kh\u00e1c nhau.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">T\u1eeb kh\u00f3a: M\u00f4\u0111em; Card m\u1ea1ng; T\u00edn hi\u1ec7u t\u01b0\u01a1ng t\u1ef1; T\u00edn hi\u1ec7u s\u1ed1.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Ngay t\u1eeb nh\u1eefng n\u0103m 60 th\u1ebf k\u1ec9 XX ng\u01b0\u1eddi ta \u0111\u00e3 ngh\u0129 c\u00e1ch s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n tho\u1ea1i b\u00ecnh th\u01b0\u1eddng \u0111\u1ec3 k\u1ebft n\u1ed1i nh\u1eefng m\u00e1y t\u00ednh \u0111\u1eb7t c\u00e1ch xa nhau, khi\u1ebfn ch\u00fang ta c\u00f3 th\u1ec3 truy\u1ec1n d\u1eef li\u1ec7u cho nhau. Th\u1ebf nh\u01b0ng \u0111\u01b0\u1eddng \u0111i\u1ec7n tho\u1ea1i ch\u1ec9 c\u00f3 th\u1ec3 truy\u1ec1n \u00e2m thanh &#8211; lo\u1ea1i t\u00edn [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[15,13],"tags":[],"class_list":["post-10326","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc","category-tin-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10326","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=10326"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10326\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=10326"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=10326"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=10326"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}