It uses a pair of mathematically related keys, one of which (public key) is used to encrypt information and the other (private key) is used to decrypt information. The key used in the traditional encryption technology adopted by PGP is called "session key" (sek). Every time it is used, PGP randomly generates an IDEA session key of 128 bits to encrypt the content. The public key and private key in public key encryption technology are used to encrypt the session key and indirectly protect the content through it. For example, when you want to send me a confidential letter or file, you must first obtain my public key and add it to your public key ring, and then use my public key to encrypt the letter. When I receive your encrypted letter, I must use its relative key to decrypt it. So, unless someone else has the private key, you can't unlock the encrypted letter you sent me. At the same time, when I use the private key to decrypt, I must also enter the password, which adds another layer of protection to the encrypted message.
Each public key and private key in PGP is accompanied by a key certificate. It generally includes the following contents:
1, key content (key expressed in hundreds of digits)
2. Key type (indicating whether the key is a public key or a private key)
3. Key length (the length of the key, expressed in binary bits)
4. Key number (used to uniquely identify the key)
5. Creation time (used to indicate time stamp)
6. User identification (information of the key creator, such as name, e-mail address, etc. )
7. Key fingerprint (128 digits, which is the only feature of the key content summary)
Introduction of PGP software under Win platform
PGP Desktop Professional Edition
PGP Desktop Professional Edition is an American PGP encryption software, which is the best and safest encryption method at present.
The core idea of this software is to protect files with logical partitions. For example, logical partition D is a hard disk partition protected by PGP, so every time you open this partition, you need to enter a password to open it, and the files in this partition are absolutely safe. When you no longer need this partition, you can close it and make it disappear from the desktop. When you open it again, you need to enter a password. Without a password, software developers can't decrypt it themselves! PGP is the most popular folder encryption software in the world. Its source code is open and has withstood the cracking challenge of thousands of top hackers. It turns out that PGP is the most secure encryption software in the world.
The commonly used version is PGP Desktop Professional, which includes email encryption and identity confirmation, data public key&etc. Private key encryption, password protection of hard disk and mobile disk, network data encryption, PGP self-extracting document creation, data security erasure and many other functions.
Final version: PGP10.02 [build13] (PGP SDK 4.0.0).
Due to the acquisition of Symantec, PGP has been integrated into Symantec's Norton and other security products as a security plug-in since 10.0.2. Now the common versions are 8. 1 and 10.02. Search the relevant download address by yourself.
You can use PGP to do the following:
1, encryption/signature and decryption/verification in any software. With PGP option and email plug-in, you can use PGP function in any software.
2. Create and manage keys. Use PGPkeys to create, view and maintain your own PGP key pairs. And add anyone's public key to your public key store.
3. Create a self-decrypting file (SDA). You can create an executable file that can be decrypted automatically. No one needs to install PGP in advance, as long as they know the encryption password of the file, they can decrypt the file. This feature is especially useful when you need to send files to people who don't have PGP installed. Moreover, this function can also compress files embedded in it, and the compression rate is similar to ZIP, slightly lower than RAR (sometimes slightly higher, such as containing a lot of text). Generally speaking, this function is excellent.
4. Create an encrypted PGPdisk file. This function can create a. pgd file, which will appear as a new partition after being loaded with PGP disk function. You can put any documents that need to be kept secret in this section. It uses both private key and password to save encrypted data, and its confidentiality is indestructible. However, it should be noted that you must remember to back up all files in the "PGP" folder in "My Documents" before reinstalling the system, so as to recover your private key after reinstalling. Remember to remember, otherwise you will never be able to open any encrypted files created under this system again!
5. Destroy files and folders permanently to free up disk space. You can use PGP shredding tool to permanently delete these sensitive files and folders without leaving any data fragments on the hard disk. You can also use PGP free space shredder to clear the hard disk space actually occupied by deleted files again. These two tools are designed to ensure that the data you deleted will never be recovered by people with ulterior motives.
Related use tutorial: top encryption software PGP desktop personal use tutorial [application recommendation]
GnuPG
GnuPG is a member of GNU project, and it is the simplest tool in information encryption technology, because it is actually the command using GnuPG.
The home page of gpg does not provide download of gpg, because American law restricts the export of encryption technology.
However, the gpg homepage only provides images downloaded from servers in other countries, and this is where I downloaded them:
ftp://ftp.gnupg.ca/binary/gnupg-w32cli- 1.4.9.exe
Then install it all the way. The default installation path is:
C:\Program Files\GNU\GnuPG
After installation, we need a place as the working directory of gpg, and create a folder anywhere, such as "My Documents" is a good place, such as this location:
\ My Documents \gpg
Create a text file in this folder and rename it to a batch file, such as startgpg.bat, as follows:
@ set path = C:\ Program Files \ GNU \ GnuPG； % PATH %
@ echo-* * Welcome to gpg encryption system * *-
@echo, please use the command gpg -h for help.
@cmd
In fact, the path of the gpg command is temporarily specified.
Run startgpg.bat, and you will enter a "command and prompt" window. You can use gpg -h to see the help information first.
You can watch the official Chinese course here:
Gnu Privacy Guard (GnuPG) Pocket Guide (Chinese Version)
Or a tutorial written by moonlight blog
A course of encrypting information and digital signature with GnuPG(PGP)
And Ruan Yifeng's blog.
Introduction to GPG-Ruan Yifeng's blog
Instant encryption
Official home page: use public key e-mail encryption to send secure e-mail
InstantCrypt is a powerful encryption tool, which uses PGP designed by open standards to send and receive secure e-mail. This is an entry-level PGP standard encryption program.
MiniPGP
There is no home page, but many download sites have it.
As the name implies, this software is a simplified version of PGP encryption and decryption tool. If you want to encrypt and decrypt some files with your friends without installing huge PGP software, then it will be your best choice!