Fajrina Blog Spot

I'll explain how to install PGP and the function of that particular software in network security...PGP is from a word Pretty Good Privacy, it is a public key enryption program originally written by Phil Zimmermann in 1991.Why PGP?For me, it is to secure email on internet because email is personal and it's private, beside that we don't want our private email or confidential documents read by anyone else. The advantages of PGP are language support and is available for many different platforms including Windows, Unix, MS DOS, OS/2, Macintosh and so on. After I do a research, the latest version of international freeware versions of PGP os 6.5.1i for Windows 95/98/NT and MacOS only while 5.0i for other platform.PGP works by combines some of the best features of both conventional and public key cryptography.PGP will compresses the plaintext that had been encrypt by user and creates a session key(secret key). Then after data is encrypted, the session key is then encrypted to the recipient's public key and transmitted along with the ciphertext to the recipient.

There are two type of crptography -> substitution and transportation. Substitution is use by use one letter to refer to another letter. This substitution divided by two type, monoalphabetic(use same letter for the whole message) and polyalphabetic(use different letter in whole message).While transportation is use by change the arragement of text and letter. This method can be divided by key and unkeyed..

example what i learn in class is:
1 2 3 4 5 6 7 8 9 10
1 T H E R E I S N O S
2 E C U R I T Y O N T
3 H I S E A R T H T H
4 E R E I S O N L Y O
5 P P O R T U N I T Y
Conclusion: for unkeyed single transportation can be develop into a matrix of 10(vertical) by 5(horizontal). This step can be try on keyed single transportation just by using matrix 10 but do not in sorting.

this is some terms that need to memorize such as :

1. Vigenere Ciphers - we must know the manual polyalphabetic cipher to perform encryption
2. Simple substitution ciphers (random) - is use for random aphabet tp improve caesar ciphers.

Other thing that i learn today is about MAC, Message Authentication Codes is key-dependent one way hash function.It accepts as input a secret key and an arbitrary-length message to be authenticated, and outputs.MAC protects both a message's data integrity as well as its authenticity.While digital signiture is use for message from particular sender and cryptography value that depends on message and sender.A digital guarantee that information has not been modified, as if it were protected by a proof seal that is broken if the content were altered.

RSA is the algorithm was publicly described in 1978 by Ron Rivest, Adi Shamir, and Leonard Adleman at MIT.The letters RSA are the initials of their surnames, listed in the same order as on the paperis an algorithm for public-key cryptography. It is the first algorithm known to be suitable for signing as well as encryption, and one of the first great advances in public key cryptography (taken from wikipedia website).

What i'm understand about IT security goals is to provide strong network logon authentication and at the same time reduce the and help desk costs that are associated with supporting users who forget their passwords or who let their passwords expire.Besides that, to preventing users from downloading or from using nontrusted and nonsigned content from the Internet. Sometimes, IT security use to provide availability, integrity,confidentiality and nonrepudiation for general business e-mail messages. I will explain about availability, integrity and confidentiality after this. Let me explain about the different between NTFS and Fat32.

Fat 32 is old file system that is simple, but if need to access from DOS or win9x, this Fat32 is suitable. Is also well-documented, readable from a large number of OSs, and supported by a wide range of tools while a newer file system that is faster, safer, space efficient, feature-rich, proprietary, undocumented at the raw bytes level, and subject to change - even within Service Packs of the same OS version. To get detail, refer to this website http://cquirke.mvps.org/ntfs.htm.

The differentiate between availability, integrity,confidentiality :

CONFIDENTIALLY -
Means that, computer or asset cannot being used by other unauthorized person because it is privacy and secrecy.
Example : there are two user had been created. User1 do not have authority to see,modified or do anything to User2 folder or file.Only User2 have authority can do anything to their computer or assets.

AVAILABILITY -
Means that, user can access their own file or information anytime they want without a failure and it remains available or secure.
Example : User1 can access their own information anytime they want but User2 cannot do anything eventhough User1 had been removed or delete by administrator.

INTEGRITY -
Means that, only own user can do any changes to their data.
Example : User1 can added, deleted or updated their data. User1 can only do the task that been set by administrator.

Let me explain how to convert from FAT disk into NTFS.There are a few step :

1. Log on Windows 2003 Server as Administrator.
2. Click [Start] and after that Click [Run]
3. Type cmd to open command line at type chkntfs d: Notes : You will get a message "D: is not dirty"
4. Then type convert d: /fs:ntfs. If the drive has a volume label, enter it when prompted.
5. Type chkntfs d : to verify that drive is now NTFS.
6. Finish.