t****t
发帖数: 6806 | 1 是同一个序列, 起点不同. 简单的说, PRNG的状态数是有限的, 一个设计的正常的PRNG
的状态(state)数等于它的周期. 每一个状态对应一个随机数输出. 如果周期小于状态
数, 那这个PRNG设计得不太理想.
-1 |
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n*****8
发帖数: 19630 | 2 这种你还考中学生吧，
叔考你一个基本的吧，通常加密算法中的PRNG是怎么产生的。
：）
: 果然是p都不懂的it从业人员
: The address space of current 64-bit OSes
: 这个你要还是不懂 就别让我再看到你了
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i****x
发帖数: 17565 | 3 冯诺依满的贡献早就不能用钱衡量了 别的不说，没他对eniac的工作，程序员这个职业
就不会存在。gates要是知道你把他俩比，估计都要被折杀了。
wiki上列了他的主要贡献领域，给你参考下
Abelian von Neumann algebra
Affiliated operator
Amenable group
Arithmetic logic unit
Artificial viscosity
Axiom of regularity
Axiom of limitation of size
Backward induction
Blast wave (fluid dynamics)
Bounded set (topological vector space)
Class (set theory)
Decoherence theory
Computer virus
Commutation theorem
Continuous geometry
Direct integral
Doubly stochastic matrix
Duality Theorem
Density matrix
... 阅读全帖 |
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f****g
发帖数: 313 | 4 I am working at application Security industry for a year, and I am still a
newbie:-) But I love to share my $0.02.
Knowledge and Skill sets:
If you are working in Web Security:
* Web technology stack, from the most basic principle like same domain
origin policy to latest technology like PostMessage, WebSocket etc.
* OWASP Top 10 Web Security Vulnerabilities
* Applied cryto. How to generate PRNG? How to store customers' password?
what is the crypto algorithms/libraries you are going to suggest d... 阅读全帖 |
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a******e
发帖数: 36306 | 5 本来拿了一个品客凑数，结帐跟我算的不一样，结果又拿了一个，还是on sale的。。
。糊涂啊
2x PRNG $1 x 2
Loreal 眼影 4.99x3
Gillete Venus 7.29
LRL REV ADV TWLT 7.79
LRL YC DSCLR CRT 24.99
CVS Beauty 7 off 35
Cosmetic CRT 4 off 12
Loreal $1x3
Loreal $2x2
Venus $3
ECB $21
30% CVS COUPON 14.49
subtotal: .55
total: .59
返ECB 10+5+3, Beauty bucks 5.5, 不赔不赚
不知道这个14.49怎么出来的
另一个单比较简单，30% + 6 off 30
LRL G360 CD EXF 5.79
LRL YC DSCLR CRT 24.99
- 6/30
- 30% CVS coupon 7.44
- Loreal coupon 2x2
- $10 ECB
没想到是先算6/30，结果oop 3.34+tax, beauty bucks只能回来3刀，算亏了... 阅读全帖 |
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g*****0
发帖数: 887 | 6 请教 帮主...为毛 你要 100股 甚至 50股的买。特别是PRNG...这么便宜的股票。。请
问有什么诀窍么 ？ |
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t*******f
发帖数: 2634 | 7 PRNG can be re-programed de ba. |
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G*******h
发帖数: 1391 | 9 估计中枢神经再生中：）
ping，prng，peng。。。
1,2,3.。。
测试，测试。。。
：） |
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t****t
发帖数: 6806 | 11 首先, 你要控制那么细的话, libc自己的rand()是个很糙的函数, 多半不合要求
其次, 你确定是每个实例都要一个自己的PRNG吗?
如果不是并行做, 你可以做完一个, 再重新用srand()设种子, 再做下一个 |
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t****t
发帖数: 6806 | 12 /dev/random is different -- /dev/random is RNG, while libc rand() or
whatever function from software is PRNG. "Real" rng must have OS support (
which /dev/random do).
most libc rand() is linear congruential generator. it's easy to implement
and fast.
however it has some severe problem, and is of low quality. |
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t****t
发帖数: 6806 | 13 then rand() is indeed a function of time(), which could be random, or could
be totally not random.
(pseudo) random generator is not a trivial topic. the quality of PRNG varies
a LOT. if your program need to use a lot of PRN (e.g. more than 2^16),
usually you have to pick a reasonable generator, instead of blindly using
the rand() comes with libc. |
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m****s
发帖数: 1481 | 14 谢谢，那看来需要换一个周期更长的prng了，我做仿真的sample数量在10^13左右，2^
31-1看来是不够了。 |
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m*****e
发帖数: 47 | 15 prng will give the same sequence of numbers |
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r*****e
发帖数: 1584 | 16 C++
例子程序不通的说。
openssl上的faq也只这样讲了一下。不甚明白。
多谢. |
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x**********n
发帖数: 2 | 17 You need SUNWski package. |
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r*****e
发帖数: 1584 | 18 我主要是不知道用 RAND_and生成的key应该用在什么地方。 |
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