Lab #2
Implement Hashing & Encryption
IS4560
1. Explain in your own words why the hash values will change when data is modified.
Hash values change because the contents of the files being hashed have changed.
MD5sum - Original File example.txt
Example.txt.md5
SHA1 - Original File example.txt
Example.txt.sha1
MD5sum – Modified File example.txt
SHA1 – Modified File example.txt
2. Why are the MD5sum and SHA1sum hash values the same every time you calculate for the “example.txt” sample file? What if it were different when you re-calculated the hash value at the other end?
Because the file is still the same, the hashes change when the files change. It would mean something changed when it was not supposed to.
3. If you were using corporate e-mail for internal and external communications but did not want to encrypt an e-mail message, what other security countermeasure can you deploy to ensure message integrity?
Digital Signature
4. If you are using corporate e-mail for external communications that contain confidential information, what other security countermeasure can you deploy to maximize confidentiality of e-mail transmissions through the Internet?
A. VPN.
5. What is the difference between MD5sum and SHA1sum hashing calculations? Which is better and why?
One of the big differences is that MD5 uses 128bit and SHA1 160bit for the length, this makes it stronger but slower to generate. This makes SHA1 a more secure choice.
6. Where can you store your public keys or public certificate files in the public domain? Is this the same thing as a Public Key Infrastructure (KI) server?
The Public Key Infrastructure creates encryption keys and manages certificate requests while the storage location is called the certificate store.
7. What do you need if you want to decrypt encrypted messages and files from a trusted sender?
You need the sender’s private key to decrypt the message.
8. What encryption mechanisms are built into...