{"id":479170,"date":"2023-08-09T10:31:59","date_gmt":"2023-08-09T10:31:59","guid":{"rendered":""},"modified":"2023-09-05T11:18:20","modified_gmt":"2023-09-05T11:18:20","slug":"stream-cipher","status":"publish","type":"wiki","link":"https:\/\/oneproxy.pro\/vn\/wiki\/stream-cipher\/","title":{"rendered":"M\u1eadt m\u00e3 d\u00f2ng"},"content":{"rendered":"<p>M\u1eadt m\u00e3 d\u00f2ng l\u00e0 m\u1ed9t m\u1eadt m\u00e3 kh\u00f3a \u0111\u1ed1i x\u1ee9ng trong \u0111\u00f3 c\u00e1c ch\u1eef s\u1ed1 v\u0103n b\u1ea3n g\u1ed1c \u0111\u01b0\u1ee3c k\u1ebft h\u1ee3p v\u1edbi lu\u1ed3ng ch\u1eef s\u1ed1 m\u1eadt m\u00e3 gi\u1ea3 ng\u1eabu nhi\u00ean (d\u00f2ng kh\u00f3a). Trong m\u1eadt m\u00e3 d\u00f2ng, m\u1ed7i ch\u1eef s\u1ed1 c\u1ee7a b\u1ea3n r\u00f5 \u0111\u01b0\u1ee3c m\u00e3 h\u00f3a l\u1ea7n l\u01b0\u1ee3t b\u1eb1ng ch\u1eef s\u1ed1 t\u01b0\u01a1ng \u1ee9ng c\u1ee7a d\u00f2ng kh\u00f3a, \u0111\u1ec3 t\u1ea1o ra m\u1ed9t ch\u1eef s\u1ed1 c\u1ee7a d\u00f2ng b\u1ea3n m\u00e3.<\/p>\n<h2>L\u1ecbch s\u1eed ngu\u1ed3n g\u1ed1c c\u1ee7a m\u1eadt m\u00e3 d\u00f2ng v\u00e0 s\u1ef1 \u0111\u1ec1 c\u1eadp \u0111\u1ea7u ti\u00ean v\u1ec1 n\u00f3<\/h2>\n<p>M\u1eadt m\u00e3 d\u00f2ng c\u00f3 m\u1ed9t l\u1ecbch s\u1eed phong ph\u00fa k\u1ec3 t\u1eeb Th\u1ebf chi\u1ebfn th\u1ee9 nh\u1ea5t. Ch\u00fang \u0111\u00e3 \u0111\u1ea1t \u0111\u01b0\u1ee3c s\u1ee9c h\u00fat \u0111\u00e1ng k\u1ec3 trong Th\u1ebf chi\u1ebfn th\u1ee9 hai nh\u1edd vi\u1ec7c s\u1eed d\u1ee5ng c\u00e1c thi\u1ebft b\u1ecb c\u01a1 kh\u00ed nh\u01b0 m\u1eadt m\u00e3 Lorenz v\u00e0 m\u00e1y Enigma c\u1ee7a \u0110\u1ee9c.<\/p>\n<p>Trong nh\u1eefng n\u0103m \u0111\u1ea7u c\u1ee7a m\u1eadt m\u00e3, c\u00e1c h\u1ec7 th\u1ed1ng th\u1ee7 c\u00f4ng \u0111\u01a1n gi\u1ea3n nh\u01b0 m\u1eadt m\u00e3 Vigene\u00e8re c\u0169ng \u0111\u01b0\u1ee3c coi l\u00e0 m\u1eadt m\u00e3 d\u00f2ng, m\u1eb7c d\u00f9 l\u00e0 nh\u1eefng h\u1ec7 th\u1ed1ng nguy\u00ean th\u1ee7y. K\u1ef7 nguy\u00ean hi\u1ec7n \u0111\u1ea1i c\u1ee7a m\u1eadt m\u00e3 d\u00f2ng b\u1eaft \u0111\u1ea7u v\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a m\u00e1y t\u00ednh k\u1ef9 thu\u1eadt s\u1ed1 v\u00e0 nhu c\u1ea7u m\u00e3 h\u00f3a t\u1ed1c \u0111\u1ed9 cao.<\/p>\n<h2>Th\u00f4ng tin chi ti\u1ebft v\u1ec1 M\u1eadt m\u00e3 lu\u1ed3ng: M\u1edf r\u1ed9ng ch\u1ee7 \u0111\u1ec1 M\u1eadt m\u00e3 lu\u1ed3ng<\/h2>\n<p>M\u1eadt m\u00e3 d\u00f2ng l\u00e0 m\u1ed9t ph\u1ea7n quan tr\u1ecdng c\u1ee7a m\u1eadt m\u00e3 hi\u1ec7n \u0111\u1ea1i, \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong nhi\u1ec1u \u1ee9ng d\u1ee5ng kh\u00e1c nhau nh\u01b0 truy\u1ec1n th\u00f4ng an to\u00e0n, ng\u00e2n h\u00e0ng tr\u1ef1c tuy\u1ebfn v\u00e0 ph\u00e1t s\u00f3ng ph\u01b0\u01a1ng ti\u1ec7n truy\u1ec1n th\u00f4ng k\u1ef9 thu\u1eadt s\u1ed1.<\/p>\n<h3>Th\u00e0nh ph\u1ea7n ch\u00ednh<\/h3>\n<ol>\n<li><strong>Ch\u00eca kh\u00f3a<\/strong>: M\u1ed9t tham s\u1ed1 b\u00ed m\u1eadt \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 m\u00e3 h\u00f3a.<\/li>\n<li><strong>Tr\u00ecnh t\u1ea1o d\u00f2ng kh\u00f3a<\/strong>: T\u1ea1o ra m\u1ed9t chu\u1ed7i c\u00e1c k\u00fd t\u1ef1 ho\u1eb7c bit gi\u1ea3 ng\u1eabu nhi\u00ean.<\/li>\n<li><strong>Thu\u1eadt to\u00e1n m\u00e3 h\u00f3a<\/strong>: K\u1ebft h\u1ee3p d\u00f2ng kh\u00f3a v\u1edbi v\u0103n b\u1ea3n g\u1ed1c, th\u01b0\u1eddng s\u1eed d\u1ee5ng XOR theo bit.<\/li>\n<\/ol>\n<h3>Thu\u1eadt to\u00e1n chung<\/h3>\n<ul>\n<li>RC4<\/li>\n<li>Salsa20<\/li>\n<li>ChaCha<\/li>\n<\/ul>\n<h2>C\u1ea5u tr\u00fac b\u00ean trong c\u1ee7a M\u1eadt m\u00e3 lu\u1ed3ng: C\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng c\u1ee7a M\u1eadt m\u00e3 lu\u1ed3ng<\/h2>\n<p>Ho\u1ea1t \u0111\u1ed9ng c\u1ee7a m\u1eadt m\u00e3 d\u00f2ng nh\u00ecn chung r\u1ea5t \u0111\u01a1n gi\u1ea3n:<\/p>\n<ol>\n<li><strong>Kh\u1edfi t\u1ea1o<\/strong>: M\u1eadt m\u00e3 \u0111\u01b0\u1ee3c kh\u1edfi t\u1ea1o b\u1eb1ng kh\u00f3a b\u00ed m\u1eadt v\u00e0 c\u00f3 th\u1ec3 l\u00e0 vect\u01a1 kh\u1edfi t\u1ea1o (IV).<\/li>\n<li><strong>T\u1ea1o d\u00f2ng kh\u00f3a<\/strong>: M\u1ed9t chu\u1ed7i gi\u1ea3 ng\u1eabu nhi\u00ean \u0111\u01b0\u1ee3c t\u1ea1o ra b\u1edfi b\u1ed9 t\u1ea1o d\u00f2ng kh\u00f3a.<\/li>\n<li><strong>M\u00e3 h\u00f3a<\/strong>: D\u00f2ng kh\u00f3a \u0111\u01b0\u1ee3c k\u1ebft h\u1ee3p v\u1edbi b\u1ea3n r\u00f5 b\u1eb1ng m\u1ed9t thao t\u00e1c \u0111\u01a1n gi\u1ea3n nh\u01b0 XOR.<\/li>\n<li><strong>gi\u1ea3i m\u00e3<\/strong>: D\u00f2ng kh\u00f3a t\u01b0\u01a1ng t\u1ef1 \u0111\u01b0\u1ee3c k\u1ebft h\u1ee3p v\u1edbi b\u1ea3n m\u00e3 \u0111\u1ec3 \u0111\u1ea3o ng\u01b0\u1ee3c qu\u00e1 tr\u00ecnh m\u00e3 h\u00f3a.<\/li>\n<\/ol>\n<h2>Ph\u00e2n t\u00edch c\u00e1c t\u00ednh n\u0103ng ch\u00ednh c\u1ee7a m\u1eadt m\u00e3 d\u00f2ng<\/h2>\n<ul>\n<li><strong>T\u1ed1c \u0111\u1ed9<\/strong>: M\u1eadt m\u00e3 d\u00f2ng th\u01b0\u1eddng nhanh v\u00e0 hi\u1ec7u qu\u1ea3.<\/li>\n<li><strong>S\u1ef1 \u0111\u01a1n gi\u1ea3n<\/strong>: Ch\u00fang th\u01b0\u1eddng c\u00f3 thi\u1ebft k\u1ebf \u0111\u01a1n gi\u1ea3n.<\/li>\n<li><strong>B\u1ea3o v\u1ec7<\/strong>: D\u1ec5 b\u1ecb t\u1ea5n c\u00f4ng n\u1ebfu tri\u1ec3n khai kh\u00f4ng \u0111\u00fang c\u00e1ch, \u0111\u1eb7c bi\u1ec7t n\u1ebfu d\u00f2ng kh\u00f3a \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng l\u1ea1i.<\/li>\n<\/ul>\n<h2>C\u00e1c lo\u1ea1i m\u1eadt m\u00e3 d\u00f2ng<\/h2>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 b\u1ea3ng v\u1ec1 m\u1ed9t s\u1ed1 lo\u1ea1i m\u1eadt m\u00e3 lu\u1ed3ng ph\u1ed5 bi\u1ebfn:<\/p>\n<table>\n<thead>\n<tr>\n<th>T\u00ean<\/th>\n<th>\u0110\u1ed9 d\u00e0i kh\u00f3a (bit)<\/th>\n<th>T\u00ednh n\u0103ng n\u1ed5i b\u1eadt<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>RC4<\/td>\n<td>40-2048<\/td>\n<td>\u0110\u01b0\u1ee3c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i trong TLS\/SSL<\/td>\n<\/tr>\n<tr>\n<td>Salsa20<\/td>\n<td>256<\/td>\n<td>M\u1ed9t ph\u1ea7n c\u1ee7a danh m\u1ee5c eSTREAM<\/td>\n<\/tr>\n<tr>\n<td>ChaCha<\/td>\n<td>256<\/td>\n<td>Phi\u00ean b\u1ea3n c\u1ea3i ti\u1ebfn c\u1ee7a Salsa20<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>C\u00e1ch s\u1eed d\u1ee5ng M\u1eadt m\u00e3 d\u00f2ng, c\u00e1c v\u1ea5n \u0111\u1ec1 v\u00e0 gi\u1ea3i ph\u00e1p li\u00ean quan \u0111\u1ebfn vi\u1ec7c s\u1eed d\u1ee5ng<\/h2>\n<ul>\n<li><strong>C\u00e1ch s\u1eed d\u1ee5ng<\/strong>: Truy\u1ec1n d\u1eef li\u1ec7u an to\u00e0n, VPN, ch\u1eef k\u00fd s\u1ed1.<\/li>\n<li><strong>C\u00e1c v\u1ea5n \u0111\u1ec1<\/strong>: Qu\u1ea3n l\u00fd kh\u00f3a, t\u00e1i s\u1eed d\u1ee5ng d\u00f2ng kh\u00f3a.<\/li>\n<li><strong>C\u00e1c gi\u1ea3i ph\u00e1p<\/strong>: Giao th\u1ee9c trao \u0111\u1ed5i kh\u00f3a an to\u00e0n, kh\u1edfi t\u1ea1o th\u00edch h\u1ee3p.<\/li>\n<\/ul>\n<h2>C\u00e1c \u0111\u1eb7c \u0111i\u1ec3m ch\u00ednh v\u00e0 nh\u1eefng so s\u00e1nh kh\u00e1c v\u1edbi c\u00e1c thu\u1eadt ng\u1eef t\u01b0\u01a1ng t\u1ef1<\/h2>\n<table>\n<thead>\n<tr>\n<th>T\u00ednh n\u0103ng<\/th>\n<th>M\u1eadt m\u00e3 lu\u1ed3ng<\/th>\n<th>Kh\u00f3a m\u1eadt m\u00e3<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u0110\u01a1n v\u1ecb m\u00e3 h\u00f3a<\/td>\n<td>Bit\/Byte<\/td>\n<td>Kh\u1ed1i c\u00f3 k\u00edch th\u01b0\u1edbc c\u1ed1 \u0111\u1ecbnh<\/td>\n<\/tr>\n<tr>\n<td>T\u1ed1c \u0111\u1ed9<\/td>\n<td>Nhanh<\/td>\n<td>N\u00f3i chung l\u00e0 ch\u1eadm h\u01a1n<\/td>\n<\/tr>\n<tr>\n<td>Th\u1ef1c hi\u1ec7n<\/td>\n<td>\u0110\u01a1n gi\u1ea3n<\/td>\n<td>T\u1ed5 h\u1ee3p<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Quan \u0111i\u1ec3m v\u00e0 c\u00f4ng ngh\u1ec7 c\u1ee7a t\u01b0\u01a1ng lai li\u00ean quan \u0111\u1ebfn m\u1eadt m\u00e3 d\u00f2ng<\/h2>\n<p>S\u1ef1 ph\u00e1t tri\u1ec3n kh\u00f4ng ng\u1eebng c\u1ee7a \u0111i\u1ec7n to\u00e1n l\u01b0\u1ee3ng t\u1eed \u0111e d\u1ecda t\u00ednh b\u1ea3o m\u1eadt c\u1ee7a m\u1eadt m\u00e3 truy\u1ec1n th\u1ed1ng. C\u00e1c m\u1eadt m\u00e3 d\u00f2ng m\u1edbi h\u01a1n c\u00f3 kh\u1ea3 n\u0103ng kh\u00e1ng l\u01b0\u1ee3ng t\u1eed c\u00f3 th\u1ec3 tr\u1edf n\u00ean c\u1ea7n thi\u1ebft. Nghi\u00ean c\u1ee9u \u0111ang di\u1ec5n ra t\u1eadp trung v\u00e0o vi\u1ec7c t\u0103ng c\u01b0\u1eddng b\u1ea3o m\u1eadt, t\u1ed1i \u01b0u h\u00f3a hi\u1ec7u su\u1ea5t v\u00e0 thi\u1ebft k\u1ebf d\u00e0nh ri\u00eang cho \u1ee9ng d\u1ee5ng.<\/p>\n<h2>C\u00e1ch s\u1eed d\u1ee5ng ho\u1eb7c li\u00ean k\u1ebft m\u00e1y ch\u1ee7 proxy v\u1edbi M\u1eadt m\u00e3 lu\u1ed3ng<\/h2>\n<p>C\u00e1c m\u00e1y ch\u1ee7 proxy, ch\u1eb3ng h\u1ea1n nh\u01b0 c\u00e1c m\u00e1y ch\u1ee7 do OneProxy cung c\u1ea5p, c\u00f3 th\u1ec3 t\u1eadn d\u1ee5ng m\u1eadt m\u00e3 lu\u1ed3ng \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o truy\u1ec1n d\u1eef li\u1ec7u an to\u00e0n. C\u00e1c k\u1ebft n\u1ed1i \u0111\u01b0\u1ee3c m\u00e3 h\u00f3a gi\u1eefa m\u00e1y kh\u00e1ch v\u00e0 m\u00e1y ch\u1ee7 proxy c\u00f3 th\u1ec3 b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u nh\u1ea1y c\u1ea3m v\u00e0 duy tr\u00ec t\u00ednh \u1ea9n danh c\u1ee7a ng\u01b0\u1eddi d\u00f9ng, t\u1eadn d\u1ee5ng t\u1ed1c \u0111\u1ed9 v\u00e0 hi\u1ec7u qu\u1ea3 c\u1ee7a m\u1eadt m\u00e3 lu\u1ed3ng.<\/p>\n<h2>Li\u00ean k\u1ebft li\u00ean quan<\/h2>\n<ul>\n<li><a href=\"https:\/\/www.example.com\" target=\"_new\" rel=\"noopener nofollow\">Gi\u1edbi thi\u1ec7u v\u1ec1 M\u1eadt m\u00e3 d\u00f2ng<\/a><\/li>\n<li><a href=\"https:\/\/www.example.com\" target=\"_new\" rel=\"noopener nofollow\">Kh\u00e1ng l\u01b0\u1ee3ng t\u1eed trong m\u1eadt m\u00e3 d\u00f2ng<\/a><\/li>\n<li><a href=\"https:\/\/oneproxy.pro\/vn\/\" target=\"_new\" rel=\"noopener\">T\u00ednh n\u0103ng b\u1ea3o m\u1eadt OneProxy<\/a><\/li>\n<\/ul>","protected":false},"featured_media":470617,"menu_order":0,"template":"","meta":{"_acf_changed":false,"content-type":"","inline_featured_image":false,"footnotes":""},"class_list":["post-479170","wiki","type-wiki","status-publish","has-post-thumbnail","hentry"],"acf":{"faq_title":"Frequently Asked Questions about <mark>Stream Cipher<\/mark>","faq_items":[{"question":"What is a Stream Cipher?","answer":"<p>A stream cipher is a symmetric key encryption method where plaintext digits are combined one at a time with a pseudorandom cipher digit stream, known as a keystream. Each plaintext digit is encrypted individually with the corresponding digit of the keystream to create the ciphertext stream.<\/p>"},{"question":"How did Stream Ciphers Originate?","answer":"<p>Stream ciphers originated during World War I and were extensively used during World War II in devices like the Lorenz cipher and the German Enigma machine. The modern era of stream ciphers began with the advent of digital computers, catering to the need for high-speed encryption.<\/p>"},{"question":"What are Some Common Stream Cipher Algorithms?","answer":"<p>Some common stream cipher algorithms include RC4, Salsa20, and ChaCha. They vary in key lengths and specific use cases, such as in secure web communication or digital media broadcasting.<\/p>"},{"question":"How Does a Stream Cipher Work?","answer":"<p>A stream cipher begins with initialization using a secret key and possibly an initialization vector (IV). The keystream generator then produces a pseudorandom sequence that is combined with the plaintext using a simple operation like XOR for encryption. Decryption is performed by recombining the same keystream with the ciphertext.<\/p>"},{"question":"What are the Key Features of Stream Ciphers?","answer":"<p>Key features of stream ciphers include speed, simplicity, and security. They are typically fast and efficient but can be vulnerable to attacks if not implemented correctly, especially if the keystream is reused.<\/p>"},{"question":"What Types of Stream Cipher Exist?","answer":"<p>Common types of stream ciphers include RC4, Salsa20, and ChaCha. They differ in key lengths and notable features such as usage in TLS\/SSL or improvements over predecessor algorithms.<\/p>"},{"question":"What are the Ways to Use Stream Ciphers, and What Problems Might Arise?","answer":"<p>Stream ciphers are used for secure data transmission, in VPNs, and for digital signatures. Problems can arise from key management and keystream reuse, but these can be addressed through secure key exchange protocols and proper initialization.<\/p>"},{"question":"What is the Future of Stream Ciphers?","answer":"<p>The future of stream ciphers may involve the development of quantum-resistant algorithms and ongoing research for increased security, performance optimization, and application-specific designs.<\/p>"},{"question":"How are Proxy Servers Associated with Stream Ciphers?","answer":"<p>Proxy servers like OneProxy can use stream ciphers to ensure secure data transmission between clients and servers. The efficiency of stream ciphers helps in protecting sensitive data and maintaining user anonymity in encrypted connections.<\/p>"}]},"_links":{"self":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/wiki\/479170","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\/479170\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/media\/470617"}],"wp:attachment":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/media?parent=479170"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}