hi! pliz help me here....
1) can u help me on using the public key    encryption to  show that encryption can be used NOT for security or protection?

2) how can i determine the minimum,average and maximum time it would take to crack a six-digit password if one can be checked every millisecond?
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

The purpose of public key is to encrypt data. Just because it is susceptable to being hacked doesn't mean that it's has no use in security and in data protection. It takes a lot to decrypt when a good key phrase is being used.

The time that is involved with decryption has many variables that must be defined before one could tell you the amount of time that it would take. The deeper the level of encryption the longer it's going to take. Obvoulsy the slower the CPU in your pc the longer it will take as well.

Here are some pages that you can look at:

Good PDF File:

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial

s0rry, we cann0t helP y0U w1th hOmew0rk ass1gnMENts

...academic honesty or other unethical behavior...  

Most commonly, this means that Experts are prohibited from doing your homework for you. They'll guide you and teach you, but don't ask them to write code to answer a question that seems like it was written for a test. It should be noted that just like bribery, while it's bad to offer a bribe, it's worse to take it -- so don't do homework.

"Homework" is loosely defined as an assigment, project or quiz offered up an instructor of a technical, trade or eductional institution as part of a scheduled course of instruction, for which the student receives some kind of credit. The Moderators know what homework looks like, and it will be your task to convince them it isn't.  

Q: how long would it take someone to crack 128 bit encryption?

When the press talks about "cracking" or "breaking" an encryption algorithm. They always seem to mean this: the "attacker" decrypted a message by guessing the secret key that was used for the encryption. This is not breaking or cracking a particular algorithm. But it does demonstrate the importance of key size. The key size -- the number of bits used to store the key, which is an integer number -- determines the size of the key space, the number of possible keys that can be used. If you knew that to decrypt a message you needed to guess a number between 1 and 10, would you feel challenged? How about between 1 and 1000? How about 1 and 1^38 (1 followed by 38 zeros). That is (roughly) the key space using a 128-bit key. For comparison purposes, let’s use a (so far) non-existent computer that can guess 1 trillion (1 followed by 12 zeroes) keys a second. On average, it would take around 2 million million million (2 followed by 18 zeroes) years to guess the key.

Public Key Cryptography: A Continuation of the Discussion

How PGP works

Passwords vs Public Key Cryptography for encryption

"s0rry, we cann0t helP y0U w1th hOmew0rk ass1gnMENts"

Nice touch,  talking to the kids in there own language :)
Budi SantosoIT Infrastructure ManagerCommented:
Encryption is process to encrypt/coding and invited for security or protection.
Public key can be spreaded except private key.
But, maybe it can used for other thing.
Ex: for research only, for riddle only, to generating random character for designer :)

what you mean about "if one can be checked every millisecond?"
Are you mean 1 character every 1 millisecond ?
CPU able to check NOT one millisecond, but 1 char=1/million millisecond.
Yes, it can be cracked easly if your six digit password is the combination of numerical variable (0-9) only.
The time to crack the password is depend :
-how fast your CPU to try (brute force).
-how long your password digit.
-what variable in your password. (0-9,a-z,A-Z,all ASCII code, or the combination of thems)
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.