{"id":475950,"date":"2023-08-09T07:24:43","date_gmt":"2023-08-09T07:24:43","guid":{"rendered":""},"modified":"2023-09-05T11:11:41","modified_gmt":"2023-09-05T11:11:41","slug":"automatic-repeat-requests","status":"publish","type":"wiki","link":"https:\/\/oneproxy.pro\/vn\/wiki\/automatic-repeat-requests\/","title":{"rendered":"Y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng"},"content":{"rendered":"<p>Y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng, th\u01b0\u1eddng \u0111\u01b0\u1ee3c vi\u1ebft t\u1eaft l\u00e0 ARQ, l\u00e0 m\u1ed9t giao th\u1ee9c \u0111\u1ec3 ki\u1ec3m so\u00e1t l\u1ed7i trong truy\u1ec1n d\u1eef li\u1ec7u. B\u1eb1ng c\u00e1ch s\u1eed d\u1ee5ng m\u00e3 ph\u00e1t hi\u1ec7n l\u1ed7i v\u00e0 x\u00e1c nh\u1eadn, giao th\u1ee9c ARQ c\u00f3 th\u1ec3 \u0111\u1ea3m b\u1ea3o vi\u1ec7c truy\u1ec1n d\u1eef li\u1ec7u kh\u00f4ng c\u00f3 l\u1ed7i, \u0111\u1ea3m b\u1ea3o r\u1eb1ng ng\u01b0\u1eddi nh\u1eadn c\u00f3 \u0111\u01b0\u1ee3c b\u1ea3n sao ch\u00ednh x\u00e1c c\u1ee7a d\u1eef li\u1ec7u do ng\u01b0\u1eddi g\u1eedi truy\u1ec1n.<\/p>\n<h2>Ngu\u1ed3n g\u1ed1c v\u00e0 l\u1ecbch s\u1eed ban \u0111\u1ea7u c\u1ee7a c\u00e1c y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng<\/h2>\n<p>Ngu\u1ed3n g\u1ed1c c\u1ee7a Y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng c\u00f3 th\u1ec3 b\u1eaft ngu\u1ed3n t\u1eeb nh\u1eefng ng\u00e0y \u0111\u1ea7u c\u1ee7a \u0111i\u1ec7n b\u00e1o v\u00e0o th\u1ebf k\u1ef7 19. C\u00e1c nh\u00e0 \u0111i\u1ec1u h\u00e0nh \u0111i\u1ec7n b\u00e1o s\u1ebd y\u00eau c\u1ea7u truy\u1ec1n l\u1ea1i c\u00e1c tin nh\u1eafn kh\u00f4ng r\u00f5 r\u00e0ng ho\u1eb7c b\u1ecb c\u1eaft x\u00e9n theo c\u00e1ch th\u1ee7 c\u00f4ng. Tuy nhi\u00ean, l\u1ea7n \u0111\u1ea7u ti\u00ean \u0111\u1ec1 c\u1eadp \u0111\u1ebfn m\u1ed9t h\u1ec7 th\u1ed1ng t\u1ef1 \u0111\u1ed9ng t\u01b0\u01a1ng t\u1ef1 ARQ \u0111\u01b0\u1ee3c t\u00ecm th\u1ea5y trong b\u1eb1ng s\u00e1ng ch\u1ebf n\u0103m 1924 c\u1ee7a A. Harry Nyquist cho \u201cH\u1ec7 th\u1ed1ng l\u1eb7p l\u1ea1i \u0111i\u1ec7n b\u00e1o\u201d.<\/p>\n<p>S\u1ef1 ph\u00e1t tri\u1ec3n v\u00e0 ho\u00e0n thi\u1ec7n c\u00e1c giao th\u1ee9c ARQ b\u1eaft \u0111\u1ea7u t\u0103ng nhanh v\u1edbi s\u1ef1 ra \u0111\u1eddi c\u1ee7a truy\u1ec1n th\u00f4ng d\u1eef li\u1ec7u s\u1ed1 trong th\u1ebf k\u1ef7 20. B\u01b0\u1edbc nh\u1ea3y v\u1ecdt \u0111\u00e1ng k\u1ec3 nh\u1ea5t trong th\u1eddi \u0111\u1ea1i n\u00e0y c\u00f3 l\u1ebd l\u00e0 s\u1ef1 ra \u0111\u1eddi c\u1ee7a ki\u1ec3m tra d\u1ef1 ph\u00f2ng theo chu k\u1ef3 (CRC) v\u00e0o nh\u1eefng n\u0103m 1960, m\u1ed9t s\u01a1 \u0111\u1ed3 m\u00e3 h\u00f3a ph\u00e1t hi\u1ec7n l\u1ed7i v\u1eabn \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i trong tri\u1ec3n khai ARQ hi\u1ec7n \u0111\u1ea1i.<\/p>\n<h2>\u0110i\u1ec3m m\u1ea5u ch\u1ed1t c\u1ee7a c\u00e1c y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng<\/h2>\n<p>Y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng l\u00e0 n\u1ec1n t\u1ea3ng cho h\u1ec7 th\u1ed1ng truy\u1ec1n d\u1eef li\u1ec7u, \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u trong qu\u00e1 tr\u00ecnh truy\u1ec1n. \u0110\u1ec3 \u0111\u1ea1t \u0111\u01b0\u1ee3c \u0111i\u1ec1u n\u00e0y, c\u00e1c giao th\u1ee9c ARQ k\u1ebft h\u1ee3p ba c\u01a1 ch\u1ebf ch\u00ednh: ph\u00e1t hi\u1ec7n l\u1ed7i, x\u00e1c nh\u1eadn v\u00e0 truy\u1ec1n l\u1ea1i.<\/p>\n<p>Trong h\u1ec7 th\u1ed1ng ARQ, ng\u01b0\u1eddi g\u1eedi \u0111\u00ednh k\u00e8m m\u00e3 ph\u00e1t hi\u1ec7n l\u1ed7i (nh\u01b0 CRC) v\u00e0o d\u1eef li\u1ec7u g\u1eedi \u0111i. Khi nh\u1eadn \u0111\u01b0\u1ee3c, ng\u01b0\u1eddi nh\u1eadn s\u1eed d\u1ee5ng thu\u1eadt to\u00e1n ph\u00e1t hi\u1ec7n l\u1ed7i t\u01b0\u01a1ng t\u1ef1 \u0111\u1ec3 x\u00e1c th\u1ef1c d\u1eef li\u1ec7u. N\u1ebfu d\u1eef li\u1ec7u kh\u00f4ng c\u00f3 l\u1ed7i, ng\u01b0\u1eddi nh\u1eadn s\u1ebd g\u1eedi x\u00e1c nh\u1eadn l\u1ea1i cho ng\u01b0\u1eddi g\u1eedi. N\u1ebfu ph\u00e1t hi\u1ec7n th\u1ea5y l\u1ed7i, ng\u01b0\u1eddi nh\u1eadn s\u1ebd g\u1eedi x\u00e1c nh\u1eadn ph\u1ee7 \u0111\u1ecbnh (NAK) ho\u1eb7c trong m\u1ed9t s\u1ed1 tr\u01b0\u1eddng h\u1ee3p, ch\u1ec9 c\u1ea7n gi\u1eef im l\u1eb7ng, nh\u1eafc ng\u01b0\u1eddi g\u1eedi truy\u1ec1n l\u1ea1i d\u1eef li\u1ec7u.<\/p>\n<h2>C\u00e1c c\u01a1 ch\u1ebf \u0111\u1eb1ng sau c\u00e1c y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng<\/h2>\n<p>C\u00e1c giao th\u1ee9c ARQ th\u01b0\u1eddng ho\u1ea1t \u0111\u1ed9ng theo c\u00e1c nguy\u00ean t\u1eafc n\u00eau tr\u00ean nh\u01b0ng kh\u00e1c nhau v\u1ec1 c\u00e1ch x\u1eed l\u00fd c\u00e1c t\u00ecnh hu\u1ed1ng c\u1ee5 th\u1ec3. M\u1ed9t s\u1ed1 c\u00e2n nh\u1eafc trong thi\u1ebft k\u1ebf ARQ bao g\u1ed3m:<\/p>\n<ul>\n<li>\u0110i\u1ec1u g\u00ec k\u00edch ho\u1ea1t vi\u1ec7c truy\u1ec1n l\u1ea1i?<\/li>\n<li>L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 x\u1eed l\u00fd c\u00e1c g\u00f3i kh\u00f4ng theo th\u1ee9 t\u1ef1?<\/li>\n<li>L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 t\u1ed1i \u01b0u h\u00f3a hi\u1ec7u qu\u1ea3 v\u00e0 th\u00f4ng l\u01b0\u1ee3ng c\u1ee7a h\u1ec7 th\u1ed1ng?<\/li>\n<\/ul>\n<p>C\u00e1c quy t\u1eafc ch\u00ednh x\u00e1c \u0111\u1ec3 x\u1eed l\u00fd c\u00e1c t\u00ecnh hu\u1ed1ng n\u00e0y x\u00e1c \u0111\u1ecbnh c\u00e1c \u0111\u1eb7c t\u00ednh hi\u1ec7u su\u1ea5t v\u00e0 h\u00e0nh vi c\u1ee7a giao th\u1ee9c ARQ. V\u00ed d\u1ee5: c\u00e1ch giao th\u1ee9c ph\u1ea3n h\u1ed3i v\u1edbi nhi\u1ec1u l\u1ea7n truy\u1ec1n kh\u00f4ng th\u00e0nh c\u00f4ng c\u00f3 th\u1ec3 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn \u0111\u1ed9 tin c\u1eady c\u1ee7a n\u00f3 trong m\u00f4i tr\u01b0\u1eddng giao ti\u1ebfp \u1ed3n \u00e0o ho\u1eb7c kh\u00f4ng \u0111\u00e1ng tin c\u1eady.<\/p>\n<h2>C\u00e1c t\u00ednh n\u0103ng ch\u00ednh c\u1ee7a Y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng<\/h2>\n<p>C\u00e1c t\u00ednh n\u0103ng n\u1ed5i b\u1eadt c\u1ee7a giao th\u1ee9c ARQ bao g\u1ed3m:<\/p>\n<ul>\n<li>Truy\u1ec1n d\u1eef li\u1ec7u kh\u00f4ng c\u00f3 l\u1ed7i: Giao th\u1ee9c ARQ c\u00f3 th\u1ec3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng ng\u01b0\u1eddi nh\u1eadn nh\u1eadn \u0111\u01b0\u1ee3c b\u1ea3n sao ch\u00ednh x\u00e1c c\u1ee7a d\u1eef li\u1ec7u do ng\u01b0\u1eddi g\u1eedi truy\u1ec1n.<\/li>\n<li>Kh\u1ea3 n\u0103ng th\u00edch \u1ee9ng: ARQ c\u00f3 th\u1ec3 th\u00edch \u1ee9ng v\u1edbi c\u00e1c m\u1ee9c \u0111\u1ed9 nhi\u1ec5u v\u00e0 t\u1ef7 l\u1ec7 l\u1ed7i kh\u00e1c nhau trong k\u00eanh li\u00ean l\u1ea1c.<\/li>\n<li>Hi\u1ec7u qu\u1ea3: B\u1eb1ng c\u00e1ch ch\u1ec9 truy\u1ec1n l\u1ea1i d\u1eef li\u1ec7u sai, ARQ tr\u00e1nh l\u00e3ng ph\u00ed b\u0103ng th\u00f4ng cho nh\u1eefng l\u1ea7n truy\u1ec1n kh\u00f4ng c\u1ea7n thi\u1ebft.<\/li>\n<\/ul>\n<h2>C\u00e1c lo\u1ea1i y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng<\/h2>\n<p>Ba lo\u1ea1i giao th\u1ee9c ARQ th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong c\u00e1c h\u1ec7 th\u1ed1ng truy\u1ec1n d\u1eef li\u1ec7u:<\/p>\n<ol>\n<li>ARQ d\u1eebng v\u00e0 ch\u1edd: D\u1ea1ng ARQ \u0111\u01a1n gi\u1ea3n nh\u1ea5t, ng\u01b0\u1eddi g\u1eedi d\u1eebng v\u00e0 ch\u1edd x\u00e1c nh\u1eadn sau m\u1ed7i l\u1ea7n truy\u1ec1n. N\u1ebfu kh\u00f4ng nh\u1eadn \u0111\u01b0\u1ee3c x\u00e1c nh\u1eadn trong m\u1ed9t kho\u1ea3ng th\u1eddi gian ch\u1edd nh\u1ea5t \u0111\u1ecbnh, ng\u01b0\u1eddi g\u1eedi s\u1ebd truy\u1ec1n l\u1ea1i d\u1eef li\u1ec7u.<\/li>\n<li>Go-Back-N ARQ: Trong ph\u01b0\u01a1ng ph\u00e1p n\u00e0y, ng\u01b0\u1eddi g\u1eedi c\u00f3 th\u1ec3 truy\u1ec1n m\u1ed9t lo\u1ea1t g\u00f3i m\u00e0 kh\u00f4ng c\u1ea7n ch\u1edd x\u00e1c nh\u1eadn, \u0111\u1ebfn m\u1ed9t gi\u1edbi h\u1ea1n nh\u1ea5t \u0111\u1ecbnh (N). N\u1ebfu ph\u00e1t hi\u1ec7n th\u1ea5y l\u1ed7i, ng\u01b0\u1eddi g\u1eedi s\u1ebd \u201cquay l\u1ea1i\u201d v\u00e0 truy\u1ec1n l\u1ea1i t\u1ea5t c\u1ea3 c\u00e1c g\u00f3i t\u1eeb th\u1eddi \u0111i\u1ec3m \u0111\u00f3 tr\u1edf \u0111i.<\/li>\n<li>ARQ l\u1eb7p l\u1ea1i c\u00f3 ch\u1ecdn l\u1ecdc: M\u1ed9t c\u1ea3i ti\u1ebfn so v\u1edbi Go-Back-N, ARQ l\u1eb7p l\u1ea1i c\u00f3 ch\u1ecdn l\u1ecdc cho ph\u00e9p ng\u01b0\u1eddi nh\u1eadn ch\u1ea5p nh\u1eadn c\u00e1c g\u00f3i kh\u00f4ng \u0111\u00fang th\u1ee9 t\u1ef1 v\u00e0 ch\u1ec9 y\u00eau c\u1ea7u truy\u1ec1n l\u1ea1i nh\u1eefng g\u00f3i b\u1ecb l\u1ed7i.<\/li>\n<\/ol>\n<h2>\u1ee8ng d\u1ee5ng th\u1ef1c t\u1ebf v\u00e0 th\u00e1ch th\u1ee9c<\/h2>\n<p>C\u00e1c giao th\u1ee9c ARQ t\u00ecm th\u1ea5y \u1ee9ng d\u1ee5ng trong h\u1ea7u h\u1ebft m\u1ecdi kh\u00eda c\u1ea1nh c\u1ee7a truy\u1ec1n th\u00f4ng d\u1eef li\u1ec7u s\u1ed1, bao g\u1ed3m m\u1ea1ng di \u0111\u1ed9ng, Wi-Fi, truy\u1ec1n th\u00f4ng v\u1ec7 tinh v\u00e0 truy\u1ec1n t\u1ec7p qua internet.<\/p>\n<p>Tuy nhi\u00ean, vi\u1ec7c s\u1eed d\u1ee5ng ARQ kh\u00f4ng ph\u1ea3i l\u00e0 kh\u00f4ng c\u00f3 th\u00e1ch th\u1ee9c. V\u00ed d\u1ee5: d\u1eef li\u1ec7u b\u1ed5 sung c\u1ea7n thi\u1ebft \u0111\u1ec3 ph\u00e1t hi\u1ec7n v\u00e0 x\u00e1c nh\u1eadn l\u1ed7i c\u00f3 th\u1ec3 l\u00e0m gi\u1ea3m b\u0103ng th\u00f4ng c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng. H\u01a1n n\u1eefa, \u0111\u1ed9 tr\u1ec5 do truy\u1ec1n l\u1ea1i c\u00f3 th\u1ec3 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn c\u00e1c \u1ee9ng d\u1ee5ng li\u00ean l\u1ea1c th\u1eddi gian th\u1ef1c nh\u01b0 VoIP v\u00e0 truy\u1ec1n ph\u00e1t video.<\/p>\n<h2>So s\u00e1nh v\u1edbi c\u00e1c giao th\u1ee9c ki\u1ec3m so\u00e1t l\u1ed7i kh\u00e1c<\/h2>\n<p>Ngo\u00e0i ARQ, hai giao th\u1ee9c ki\u1ec3m so\u00e1t l\u1ed7i ch\u00ednh kh\u00e1c \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong truy\u1ec1n d\u1eef li\u1ec7u:<\/p>\n<ul>\n<li>\n<p>S\u1eeda l\u1ed7i chuy\u1ec3n ti\u1ebfp (FEC): FEC m\u00e3 h\u00f3a d\u1eef li\u1ec7u theo c\u00e1ch cho ph\u00e9p ng\u01b0\u1eddi nh\u1eadn s\u1eeda m\u1ed9t s\u1ed1 l\u1ed7i h\u1ea1n ch\u1ebf. Kh\u00f4ng gi\u1ed1ng nh\u01b0 ARQ, FEC kh\u00f4ng y\u00eau c\u1ea7u truy\u1ec1n l\u1ea1i d\u1eef li\u1ec7u nh\u01b0ng n\u00f3 y\u00eau c\u1ea7u nhi\u1ec1u b\u0103ng th\u00f4ng h\u01a1n cho c\u00e1c m\u00e3 s\u1eeda l\u1ed7i b\u1ed5 sung.<\/p>\n<\/li>\n<li>\n<p>ARQ lai (HARQ): HARQ k\u1ebft h\u1ee3p c\u00e1c y\u1ebfu t\u1ed1 c\u1ee7a c\u1ea3 ARQ v\u00e0 FEC. N\u1ebfu g\u00f3i nh\u1eadn \u0111\u01b0\u1ee3c c\u00f3 l\u1ed7i, tr\u01b0\u1edbc ti\u00ean HARQ s\u1ebd c\u1ed1 g\u1eafng s\u1eeda l\u1ed7i b\u1eb1ng FEC. N\u1ebfu th\u1ea5t b\u1ea1i, n\u00f3 s\u1ebd quay tr\u1edf l\u1ea1i c\u01a1 ch\u1ebf ARQ y\u00eau c\u1ea7u truy\u1ec1n l\u1ea1i.<\/p>\n<\/li>\n<\/ul>\n<h2>Quan \u0111i\u1ec3m v\u00e0 c\u00f4ng ngh\u1ec7 t\u01b0\u01a1ng lai<\/h2>\n<p>V\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n kh\u00f4ng ng\u1eebng c\u1ee7a c\u00f4ng ngh\u1ec7 truy\u1ec1n th\u00f4ng d\u1eef li\u1ec7u, c\u00e1c giao th\u1ee9c ARQ c\u0169ng \u0111ang \u0111\u01b0\u1ee3c c\u1ea3i ti\u1ebfn v\u00e0 t\u1ed1i \u01b0u h\u00f3a. V\u00ed d\u1ee5: c\u00e1c giao th\u1ee9c \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf cho m\u1ea1ng 5G m\u1edbi s\u1eed d\u1ee5ng s\u01a1 \u0111\u1ed3 HARQ ph\u1ee9c t\u1ea1p c\u00f3 th\u1ec3 th\u00edch \u1ee9ng v\u1edbi \u0111i\u1ec1u ki\u1ec7n c\u1ee7a k\u00eanh li\u00ean l\u1ea1c trong th\u1eddi gian th\u1ef1c, t\u1ed1i \u0111a h\u00f3a th\u00f4ng l\u01b0\u1ee3ng d\u1eef li\u1ec7u v\u00e0 gi\u1ea3m thi\u1ec3u \u0111\u1ed9 tr\u1ec5.<\/p>\n<p>H\u01a1n n\u1eefa, nghi\u00ean c\u1ee9u trong t\u01b0\u01a1ng lai v\u1ec1 truy\u1ec1n th\u00f4ng v\u00e0 \u0111i\u1ec7n to\u00e1n l\u01b0\u1ee3ng t\u1eed c\u00f3 th\u1ec3 d\u1eabn \u0111\u1ebfn c\u00e1c lo\u1ea1i giao th\u1ee9c ki\u1ec3m so\u00e1t l\u1ed7i m\u1edbi, c\u00f3 kh\u1ea3 n\u0103ng thay th\u1ebf ho\u1eb7c b\u1ed5 sung cho ARQ truy\u1ec1n th\u1ed1ng.<\/p>\n<h2>M\u00e1y ch\u1ee7 proxy v\u00e0 y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng<\/h2>\n<p>C\u00e1c m\u00e1y ch\u1ee7 proxy, gi\u1ed1ng nh\u01b0 c\u00e1c m\u00e1y ch\u1ee7 do OneProxy cung c\u1ea5p, c\u0169ng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c h\u01b0\u1edfng l\u1ee3i t\u1eeb c\u00e1c giao th\u1ee9c ARQ. L\u00e0 trung gian gi\u1eefa m\u00e1y kh\u00e1ch v\u00e0 internet, m\u00e1y ch\u1ee7 proxy c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng ARQ \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c truy\u1ec1n qua ch\u00fang. Ch\u1eb3ng h\u1ea1n, m\u00e1y ch\u1ee7 proxy c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng ARQ \u0111\u1ec3 truy\u1ec1n l\u1ea1i d\u1eef li\u1ec7u n\u1ebfu g\u1eb7p l\u1ed7i do t\u1eafc ngh\u1ebdn m\u1ea1ng, m\u1ea5t g\u00f3i ho\u1eb7c c\u00e1c s\u1ef1 c\u1ed1 kh\u00e1c.<\/p>\n<p>B\u1eb1ng c\u00e1ch \u0111\u00f3, m\u00e1y ch\u1ee7 proxy c\u00f3 th\u1ec3 c\u1ea3i thi\u1ec7n \u0111\u1ed9 tin c\u1eady c\u1ee7a k\u1ebft n\u1ed1i c\u1ee7a m\u00e1y kh\u00e1ch, \u0111\u1eb7c bi\u1ec7t trong c\u00e1c t\u00ecnh hu\u1ed1ng c\u00f3 m\u1ea1ng kh\u00f4ng \u1ed5n \u0111\u1ecbnh ho\u1eb7c kh\u00f4ng \u0111\u00e1ng tin c\u1eady.<\/p>\n<h2>Li\u00ean k\u1ebft li\u00ean quan<\/h2>\n<p>\u0110\u1ec3 \u0111\u1ecdc th\u00eam v\u1ec1 Y\u00eau c\u1ea7u l\u1eb7p l\u1ea1i t\u1ef1 \u0111\u1ed9ng v\u00e0 c\u00e1c kh\u00e1i ni\u1ec7m li\u00ean quan, h\u00e3y xem x\u00e9t c\u00e1c t\u00e0i nguy\u00ean sau:<\/p>\n<ol>\n<li><a href=\"https:\/\/www.geeksforgeeks.org\/automatic-repeat-request-arq\/\" target=\"_new\" rel=\"noopener nofollow\">Hi\u1ec3u ARQ trong truy\u1ec1n th\u00f4ng d\u1eef li\u1ec7u<\/a><\/li>\n<li><a href=\"https:\/\/www.researchgate.net\/publication\/221166636_Automatic_repeat_request_ARQ_in_wireless_networks\" target=\"_new\" rel=\"noopener nofollow\">ARQ trong truy\u1ec1n th\u00f4ng kh\u00f4ng d\u00e2y<\/a><\/li>\n<li><a href=\"https:\/\/www.cambridge.org\/core\/journals\/designs-codes-and-cryptography\/article\/error-control-coding-in-digital-communication-systems\/5A7A5649D45CC3CB8FE4598D251F94AB\" target=\"_new\" rel=\"noopener nofollow\">\u0110i s\u00e2u v\u00e0o m\u00e3 ki\u1ec3m so\u00e1t l\u1ed7i<\/a><\/li>\n<li><a href=\"https:\/\/oneproxy.pro\/vn\/\" target=\"_new\" rel=\"noopener\">OneProxy \u2013 M\u00e1y ch\u1ee7 proxy ch\u1ea5t l\u01b0\u1ee3ng cao<\/a><\/li>\n<\/ol>","protected":false},"featured_media":467673,"menu_order":0,"template":"","meta":{"_acf_changed":false,"content-type":"","inline_featured_image":false,"footnotes":""},"class_list":["post-475950","wiki","type-wiki","status-publish","has-post-thumbnail","hentry"],"acf":{"faq_title":"Frequently Asked Questions about <mark>Understanding Automatic Repeat ReQuests (ARQ)<\/mark>","faq_items":[{"question":"What is an Automatic Repeat ReQuest (ARQ)?","answer":"<p>An Automatic Repeat ReQuest (ARQ) is a protocol used in data transmission to ensure error-free data delivery. It uses mechanisms like error detection codes and acknowledgments to validate data transmission.<\/p>"},{"question":"Where did Automatic Repeat ReQuests originate?","answer":"<p>The concept of Automatic Repeat ReQuests originated from the early days of telegraphy in the 19th century. Telegraph operators would manually request retransmission of messages that were unclear or garbled. The first automated system similar to ARQ appeared in A. Harry Nyquist's 1924 patent for a \"Telegraph Repeat System\".<\/p>"},{"question":"What are the key features of ARQ?","answer":"<p>Key features of ARQ include error-free data delivery, adaptability to varying levels of noise and error rates in the communication channel, and efficiency through only retransmitting erroneous data.<\/p>"},{"question":"What are the types of ARQ?","answer":"<p>The three commonly used types of ARQ protocols are Stop-and-Wait ARQ, Go-Back-N ARQ, and Selective Repeat ARQ. They differ based on how they handle acknowledgment and retransmission of data packets.<\/p>"},{"question":"What are the practical applications of ARQ?","answer":"<p>ARQ protocols are used in almost every aspect of digital data communication, including cellular networks, Wi-Fi, satellite communication, and file transfers over the internet.<\/p>"},{"question":"What are the challenges associated with using ARQ?","answer":"<p>The challenges associated with using ARQ include decreased usable bandwidth due to additional data for error detection and acknowledgments, and delays introduced by retransmissions that can affect real-time communication applications.<\/p>"},{"question":"How are ARQ and Proxy Servers related?","answer":"<p>Proxy servers can benefit from ARQ protocols as intermediaries between the client and the internet. They can use ARQ to ensure the integrity of data transmitted through them, improving the reliability of the client's connection in scenarios with unstable or unreliable networks.<\/p>"},{"question":"How is ARQ evolving with new technologies?","answer":"<p>With the evolution of data communication technologies, ARQ protocols are also being refined and optimized. For instance, protocols designed for new 5G networks use sophisticated Hybrid ARQ schemes. Also, future research in quantum communication could lead to new types of error control protocols.<\/p>"}]},"_links":{"self":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/wiki\/475950","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/wiki"}],"about":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/types\/wiki"}],"version-history":[{"count":0,"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/wiki\/475950\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/media\/467673"}],"wp:attachment":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/media?parent=475950"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}