Tuesday, April 17, 2012

Einstein vs Professor

This story is retrieved from the Internet. Though the authenticity of this conversation is still in question, it's still worth it to read. Enjoy.

Professor : You are a Christian, aren’t you, son ?
Student : Yes, sir.
Professor: So, you believe in GOD ?
Student : Absolutely, sir.
Professor : Is GOD good ?
Student : Sure.
Professor: Is GOD all powerful ?
Student : Yes.
Professor: My brother died of cancer even though he prayed to GOD to heal him. Most of us would attempt to help others who are ill. But GOD didn’t. How is this GOD good then? Hmm?

(Student was silent.)

Professor: You can’t answer, can you ? Let’s start again, young fella. Is GOD good?
Student : Yes.
Professor: Is satan good ?
Student : No.
Professor: Where does satan come from ?
Student : From … GOD …
Professor: That’s right. Tell me son, is there evil in this world?
Student : Yes.
Professor: Evil is everywhere, isn’t it ? And GOD did make everything. Correct?
Student : Yes.
Professor: So who created evil ?

(Student did not answer.)

Professor: Is there sickness? Immorality? Hatred? Ugliness? All these terrible things exist in the world, don’t they?
Student : Yes, sir.
Professor: So, who created them ?

(Student had no answer.)

Professor: Science says you have 5 Senses you use to identify and observe the world around you. Tell me, son, have you ever seen GOD?
Student : No, sir.
Professor: Tell us if you have ever heard your GOD?
Student : No , sir.
Professor: Have you ever felt your GOD, tasted your GOD, smelt your GOD? Have you ever had any sensory perception of GOD for that matter?
Student : No, sir. I’m afraid I haven’t.
Professor: Yet you still believe in Him?
Student : Yes.
Professor : According to Empirical, Testable, Demonstrable Protocol, Science says your GOD doesn’t exist. What do you say to that, son?
Student : Nothing. I only have my faith.
Professor: Yes, faith. And that is the problem Science has.
Student : Professor, is there such a thing as heat?
Professor: Yes.
Student : And is there such a thing as cold?
Professor: Yes.
Student : No, sir. There isn’t.

(The lecture theater became very quiet with this turn of events.)

Student : Sir, you can have lots of heat, even more heat, superheat, mega heat, white heat, a little heat or no heat. But we don’t have anything called cold. We can hit 458 degrees below zero which is no heat, but we can’t go any further after that. There is no such thing as cold. Cold is only a word we use to describe the absence of heat. We cannot measure cold. Heat is energy. Cold is not the opposite of heat, sir, just the absence of it.

(There was pin-drop silence in the lecture theater.)

Student : What about darkness, Professor? Is there such a thing as darkness?
Professor: Yes. What is night if there isn’t darkness?
Student : You’re wrong again, sir. Darkness is the absence of something. You can have low light, normal light, bright light, flashing light. But if you have no light constantly, you have nothing and its called darkness, isn’t it? In reality, darkness isn’t. If it is, well you would be able to make darkness darker, wouldn’t you?
Professor: So what is the point you are making, young man ?
Student : Sir, my point is your philosophical premise is flawed.
Professor: Flawed ? Can you explain how?
Student : Sir, you are working on the premise of duality. You argue there is life and then there is death, a good GOD and a bad GOD. You are viewing the concept of GOD as something finite, something we can measure. Sir, Science can’t even explain a thought. It uses electricity and magnetism, but has never seen, much less fully understood either one. To view death as the opposite of life is to be ignorant of the fact that death cannot exist as a substantive thing.

Death is not the opposite of life: just the absence of it. Now tell me, Professor, do you teach your students that they evolved from a monkey?

Professor: If you are referring to the natural evolutionary process, yes, of course, I do.
Student : Have you ever observed evolution with your own eyes, sir?

(The Professor shook his head with a smile, beginning to realize where the argument was going.)

Student : Since no one has ever observed the process of evolution at work and cannot even prove that this process is an on-going endeavor. Are you not teaching your opinion, sir? Are you not a scientist but a preacher?

(The class was in uproar.)

Student : Is there anyone in the class who has ever seen the Professor’s brain?

(The class broke out into laughter. )

Student : Is there anyone here who has ever heard the Professor’s brain, felt it, touched or smelt it? No one appears to have done so. So, according to the established Rules of Empirical, Stable, Demonstrable Protocol, Science says that you have no brain, sir. With all due respect, sir, how do we then trust your lectures, sir?

(The room was silent. The Professor stared at the student, his face unfathomable.)

Professor: I guess you’ll have to take them on faith, son.
Student : That is it sir … Exactly ! The link between man & GOD is FAITH. That is all that keeps things alive and moving.

P.S.

I believe you have enjoyed the conversation. And if so, you’ll probably want your friends / colleagues to enjoy the same, won’t you?

Forward this to increase their knowledge … or FAITH.

By the way, that student was EINSTEIN.

Saturday, April 7, 2012

Public Key Infrastructure Fundamental (Part 1)

Public key infrastructure is an infrastructure developed to ensure the data security that is being transfered within insecure network.

Public-Key Infrastructure
Source: Wikimedia

If we talk about PKI, we will talk about some common terms used in this area, such as encryption, digital signatures, public keys, private keys.

In Part 1 of this post, we will explore about the two terms, which are encryption and digital signatures. Public keys and private keys will be discussed in Part 2 of this post.

Encryption

Encryption can be considered as a process to disguise something as something else. This is most likely similar with people write letter to other using words that are understood just between them. This way, even if the letter is being stolen, the bad guy will not be able to read it and understand the content of it. Besides encryption, there is another term known as decryption. Decryption is basically the reverse process of encryption. It means that, we try to reverse the letter that is encrypted using strange words back to normal words that can be understood by human brain easier (or, in computer context, can be read by the computer, though it's not essentially the whole concept).

Encryption/decryption process has long been used in computer security to secure the data that is considered as private and can only be seen by certain persons. There are many algorithms exist to perform the encryption process, such as DES (Data Encryption Standard), 3DES (3 times encryption using DES), and AES (Advanced Encryption Standard). AES actually supersedes as standard encryption algorithm used by US Government.

The AES algorithm is commonly known as symmetric-key algorithm. Symmetric-key algorithm is an algorithm for that use shared secret-key to encrypt and decrypt the data. 3DES is one algorithm that is known to use symmetric-key concept. Other algorithms are blowfish, twofish, CAST-128, and IDEA.

Public-key cryptography, on the other hand, uses two different key to encrypt and decrypt the data. One used to encrypt is know as public key, whilst the other is known as private key. One algorithm that is known to use public-key cryptography is RSA. RSA stands for Ron RivestAdi Shamir and Leonard Adleman. They are the ones to publicly described it in 1978.

Public-Key Encryption
Source: Globus

Digital Signatures

Digital signature, as the name describes, is just like a human signature but in a digital format. This signature is used to proof the authenticity of the data that is transfered over the network. Valid digital signatures means that the data is the same as it is transfered by the sender and not being altered by irresponsible person.

Digital Signature Concept
Source: Wikimedia

As can be seen from the above diagram, the concept of digital signature is quite simple. The data's signature will be computed using hash algorithm and then encrypted using the signer's private key. The receiver will then decrypt the signature using the signer's public key and compare the value with the computed has value of the received data. If the value are the same, then the received can pretty sure that the data is valid and not tampered along the way.

Below are some reasons to use digital signatures:

  1. Authentication. By using the digital signature, we can make sure that the data sent is owned by specific user that is considered to be the sender.
  2. Integrity. By using the digital signature, we can make sure that the data sent is not being tampered by irresponsible person when being transferred.
  3. Non-repudiation. By using the digital signature, we can make sure that the sender, at some time in the future, cannot decline that he already signed the data.