[Question] Cipher ?

06/30/2012 07:42 romeoromeo#1
Greetings ....
Please . if you not willing to answer this ....DO not tell me to search Or Go learn bla bla .... just Do not comment
there will be No reason at all of these fourms if we will search on google or wiki .. plus if i know how to search for my answers i will not ask .
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i wish if anybody will answer this . to just talk alot as much as possible .
coz the "half line" answers doesnt fit my slow brain .

the questions is ... what is Cipher ...
my question is NOT about how to find it . and its NOT about what is the conquer new cipher ...
its simply what is it ..... how to know which is which ...
the names i know such as blowfish , crc32 , hash , md5 .... i do not know what does it mean . or how it started , devoloped , coded ..or why every "style " has diff name ... how to understand the logarithm behind it ?

if the class is NOT named with the cipher name how to know which one is it .
... how many are they ? !! and what are the most known .
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well that is enough . ... .
06/30/2012 08:14 Zeroxelli#2
06/30/2012 17:21 I don't have a username#3
"there will be No reason at all of these fourms if we will search on google or wiki"

Yes there is. To discuss different subjects, but learning purpose mostly no... Google is your friend.
06/30/2012 18:02 romeoromeo#4
Quote:
Originally Posted by I don't have a username View Post
"there will be No reason at all of these fourms if we will search on google or wiki"

Yes there is. To discuss different subjects, but learning purpose mostly no... Google is your friend.
that was the only line you did read ? !!!!!!!!!!!!!!!


and this fourm is "discuss and questions" . change the name..... or change rules to "Do NOT try to learn anything here" .
06/30/2012 18:34 Zeroxelli#5
Never try and learn anything from just one source, it will most likely be imcomplete and not 100% true. Use multiple sources so that you can compare and find the truth in all of it, thereby learning more efficiently.
06/30/2012 19:02 I don't have a username#6
Quote:
Originally Posted by romeoromeo View Post
that was the only line you did read ? !!!!!!!!!!!!!!!


and this fourm is "discuss and questions" . change the name..... or change rules to "Do NOT try to learn anything here" .
No I took that line out, because it was plain stupidity from your side, but reading this just made me laugh and realize what a waste of time you are.
06/30/2012 20:36 romeoromeo#7
Quote:
Originally Posted by I don't have a username View Post
No I took that line out, because it was plain stupidity from your side, but reading this just made me laugh and realize what a waste of time you are.
you are just giving me a free invitation to insult you back ... but i will just remind you of that line which i think you did not read .
Quote:
Please . if you not willing to answer this ....DO not tell me to search Or Go learn bla bla .... just Do not comment
06/30/2012 20:42 Zeroxelli#8
While it is admirable to ask that people do not fill up your thread will things not related to your question(s), you have to realize that barely anyone would actually listen to this request, and be prepared to deal with any response(s) you get.
06/30/2012 20:42 romeoromeo#9
Quote:
Originally Posted by Zeroxelli View Post
Never try and learn anything from just one source, it will most likely be imcomplete and not 100% true. Use multiple sources so that you can compare and find the truth in all of it, thereby learning more efficiently.
i agree with you ... but use multiple sources for something i know what is it .
i know nothing about ciphers ... what i know is . every thing change the data in way that only sender and Target can read it ... is cipher ...
Quote:

how to know which is which ...
the names i know such as blowfish , crc32 , hash , md5 .... i do not know what does it mean . or how it started , devoloped , coded ..or why every "style " has diff name ... how to understand the logarithm behind it ?

if the class is NOT named with the cipher name how to know which one is it .
06/30/2012 20:54 Zeroxelli#10
There are multiple ways to figure out what cipher something is. For example, you take a look at various qualities of the hash. One of the biggest give-aways for finding what cipher something is encrypted with is the length of the hash.

Hash is usually the product/result of an encryption.

CRC32 is the 32bit form of a cyclic redundancy check, usually used to verify files.

MD5 is the third (I believe, don't quote me on that, though.) installment of the message digest algorithm, a very common encryption algorithm. This is a hash function, not a cipher.

Blowfish is another very common cipher, but the difference between MD5 and Blowfish, is MD5 cannot be decrypted. Once MD5 is encrypted, the contents can only be found by finding something that, when encrypted, generates the same hash. Blowfish on the other hand, can be decrypted. Because with a cipher, you can both encrypt AND decrypt, whereas with a hash function, you can only encrypt. (Again, don't quote me. This is what I have learned, which may not be 100% fact. Hopefully someone else will verify my statements or correct me.)

Hope that helps you understand a bit more.
06/30/2012 22:19 CptSky#11
Quote:
Originally Posted by Zeroxelli View Post
[...]Hash is usually the product/result of an encryption.

CRC32 is the 32bit form of a cyclic redundancy check, usually used to verify files.

MD5 is the third (I believe, don't quote me on that, though.) installment of the message digest algorithm, a very common encryption algorithm. This is a hash function, not a cipher.

Blowfish is another very common cipher, but the difference between MD5 and Blowfish, is MD5 cannot be decrypted. Once MD5 is encrypted, the contents can only be found by finding something that, when encrypted, generates the same hash. Blowfish on the other hand, can be decrypted. Because with a cipher, you can both encrypt AND decrypt, whereas with a hash function, you can only encrypt. (Again, don't quote me. This is what I have learned, which may not be 100% fact. Hopefully someone else will verify my statements or correct me.)

Hope that helps you understand a bit more.
CRC32 is a checksum algorithm which is a specific hash function type. Checksums have high dispersion rate and are fast, but they also have several collisions. They're there to authenticate data.

MD5 is a cryptographic hash function. There should be no collision as it is used for cryptography (password protection). However, MD5 is not collision resistant, so, birthday attacks are possible. Also, there are bunch of dictionaries for brute-force and rainbow attacks.

Blowfish is a block cipher which is different of a stream cipher.

For MD5, data is hashed, not encrypted. Encryption suppose a possibility to get the original data back. Hash suppose that for any unique input, it will be an unique output. To get that, you can't use reversible operations.
06/30/2012 22:43 Zeroxelli#12
Quote:
Originally Posted by CptSky View Post
CRC32 is a checksum algorithm which is a specific hash function type. Checksums have high dispersion rate and are fast, but they also have several collisions. They're there to authenticate data.

MD5 is a cryptographic hash function. There should be no collision as it is used for cryptography (password protection). However, MD5 is not collision resistant, so, birthday attacks are possible. Also, there are bunch of dictionaries for brute-force and rainbow attacks.

Blowfish is a block cipher which is different of a stream cipher.

For MD5, data is hashed, not encrypted. Encryption suppose a possibility to get the original data back. Hash suppose that for any unique input, it will be an unique output. To get that, you can't use reversible operations.
Thanks again, Cpt. That's pretty helpful, even to me. I wasn't fully aware of the differences between a hash an the product of an encryption, but now I've got it.

As far as MD5 goes, maybe four or so years ago, me and a small team of people from the HackThisSite! staff put together a rather large database containing the MD5 hashes of every possible combination of characters and symbols up to a length of 16. Not only did it take bloody forever, but the amount of space it took up was enormous, not to mention it took around a minute to receive a match, at least. Though, it was certainly faster than a brute force method. We were actually fairly successful with using that method to get the plain-text of any MD5 people threw at our test page. It's really too bad that we lost the data, it took months to accumulate, and was rather fun. :)
06/30/2012 23:16 romeoromeo#13
CptSky and Zeroxelli..... Thank you so much .
all what you said is very new information to me and i really feel ashame of my next question .......
as i said i know nothing at all about encryption or Cipher that i dont even know the diff between them but i know that cipher is tool (code) used for encryption ... (wong ? right ? )
all those names are still meaningless to me . i know the "translation" but not the concept
hash function ,Checksums ,collision , brute-force and rainbow attacks, block cipher , stream cipher.
if you please have a very basicks start to all that ... Book or site or link . or vids .
my brain is white page ... and u have the brush . draw whatever you wish .
06/30/2012 23:19 Zeroxelli#14
I would recommend going back and reading the links in the post where I answered your question before: [Only registered and activated users can see links. Click Here To Register...]

And also, search for an explanation of how ciphers and hash functions work, try and find the simplest explanation you can. It's better if you understand coding a little bit first, though.
06/30/2012 23:43 romeoromeo#15
Quote:
It's better if you understand coding a little bit first
i still apreciate your help and respect you so much .. but did not expect that comment from you , but i really understand ... my questions are so newbies questions .
few months ago i wasnt know what is the meaning of packets . and did asked lot of questions alike . and now i do understant lot of it . and can analyse packets my self (except Poker to be honest )
and im kinda able to understand any code inside the source as long as it doesnt belong to cipher or encryption
i do not want to code encryption/cipher . i want to understand it .
same as i had CCNA but never coded something related to it ...