technetcalwindows server2008 R2 (1-4CPU,5CAL) ,其中的5CAL是什么意思？在一个2U服务器上安装配送的正版系统

technetcal 时间:2020-11-17 阅读:()

SHA-1的应用

SHA-1, SHA-224, SHA-256, SHA-384 和 SHA-512 都被需要安全散列算法的美国联邦政府所应用，他们也使用其他的密码算法和协定来保护敏感的未保密资料。FIPS PUB 180-1 也鼓励私人或商业组织使用 SHA-1 加密。Fritz-chip 将很可能使用 SHA-1 散列函数来实现个人电脑上的数位版权管理。首先推动安全散列算法出版的是已合并的数位签章标准。 SHA 散列函数已被做为 SHACAL 分组密码算法的基础。 SHA-1 的描述以下是 SHA-1 算法的伪代码： (Initialize variables:) a = h0 = 0x67452301 b = h1 = 0xEFCDAB89 c = h2 = 0x98BADCFE d = h3 = 0x10325476 e = h4 = 0xC3D2E1F0 (Pre-processing:) paddedmessage = (message) append 1 while length(paddedmessage) mod 512 <> 448: paddedmessage = paddedmessage append 0 paddedmessage = paddedmessage append (length(message) in 64-bit format) (Process the message in essive 512-bit chunks:) while 512-bit chunk(s) remain(s): break the current chunk into sixteen 32-bit words w(i), 0 <= i <= 15 (Extend the sixteen 32-bit words into eighty 32-bit words:) for i from 16 to 79: w(i) = (w(i-3) xor w(i-8) xor w(i-14) xor w(i-16)) leftrotate 1 (Main loop:) for i from 0 to 79: temp = (a leftrotate 5) + f(b,c,d) + e + k + w(i) (note: all addition is mod 2^32) where: (0 <= i <= 19): f(b,c,d) = (b and c) or ((not b) and d), k = 0x5A827999 (20 <= i <= 39): f(b,c,d) = (b xor c xor d), k = 0x6ED9EBA1 (40 <= i <= 59): f(b,c,d) = (b and c) or (b and d) or (c and d), k = 0x8F1BBCDC (60 <= i <= 79): f(b,c,d) = (b xor c xor d), k = 0xCA62C1D6 e = d d = c c = b leftrotate 30 b = a a = temp h0 = h0 + a h1 = h1 + b h2 = h2 + c h3 = h3 + d h4 = h4 + e digest = hash = h0 append h1 append h2 append h3 append h4 注意：FIPS PUB 180-1 展示的构想，用以下的公式替代可以增进效能： (0 <= i <= 19): f(b,c,d) = (d xor (b and (c xor d))) (40 <= i <= 59): f(b,c,d) = (b and c) or (d and (b or c))) SHA-1在许多安全协议中广为使用，包括TLS和SSL、PGP、SSH、S/MIME和IPsec，曾被视为是MD5（更早之前被广为使用的散列函数）的后继者。