What is Symmetric Key Cryptography? What are the Challenges in symmetric key cryptography?

 Symmetric Key Cryptography:

After reading the above contents you are able to answer following questions.

1. What is mean by unsecure channel?

2. What is Symmetric Key? 

(Symmetric Key means same Key used for both Encryption & Decryption)

3. What are the various Symmetric key algorithm?

4. What is the meaning of Key?

5. How Symmetric key Cryptography works explain with example?

6. What are the challenges of symmetric key cryptography?