A digital signature or defined digital signature is basically a way to ensure that electronic documents (e-mail, documents, text files, etc.) are authentic. Authentic means that you know who created the document and know that the document has not been altered or edited in any way except by the person who first created it. Digital signature is a very important security technology today, especially to avoid fraud and cybercrime increasingly rampant.
Digital Signature according to globalconnex relies on several types of encryption to ensure authentication. Encryption is the process of taking all the data that is on a computer and sending it to another computer, and encoding it into a form that can only be solved by a legitimate computer. Authentication is the process of verifying information coming from a trusted source. Both of these processes work simultaneously to form digital signatures.
There are several ways to authenticate a person or information on a computer:
The use of usernames and passwords gives the most common form of authentication according to globalconnex. You enter a name and password when prompted by the computer. The system checks the pair against a secure file for confirmation. If any of the names or passwords do not match, then you are not allowed to access further.
Checksum. This is probably one of the oldest methods of ensuring the correct data, checksum also provides a form of authentication when an invalid checksum indicates that the data has been altered in some way. A checksum is specified in one of two ways. For example, the checksum of the packet is 1 byte, which means it can have a maximum value of 255. If the number of other bytes in the packet is 255 or less, then the checksum contains the exact values. However, if the number of other bytes is more than 255, then the checksum is the rest of the total value after it is divided by 256. See this example:
Byte 1 = 201
Byte 2 = 224
Byte 3 = 75
Byte 4 = 118
Byte 5 = 250
Byte 6 = 14
Byte 7 = 180
Byte 8 = 79
Total = 1141
1141 divided by 256 equals 4,457 (rounded to 4). Multiply 4 x 256 = 1024. 1141 minus 1024 equals checksum 117.
CRC (Cyclic Redundancy Check). CRC is similar in concept to checksum but uses polynomial division to determine CRC value, usually with length of 16 or 32 bit. The advantage of CRC is its accuracy. If one bit is incorrect, the CRC value will not match. Checksum and CRC combinations are excellent for preventing random errors in transmission, but little protection from deliberate attack on data.
Private Key Encryption. Private Key means that each computer has a secret key (code) that can be used to encrypt packet information before it is sent across the network to another computer. The private key requires that you know which computers communicate with each other and to install the keys on each computer. Private key encryption is basically the same secret code that each computer must know in order to decode information. The code will give you the key to decoding the message. For simplicity, let’s say you create a message encoded to your friend where each letter is replaced with the next third letter. So for example the letter “A” to “D” and “B” to “E” and so on. You have told your trusted friend that the code is “3 letter shift”. Your friend got the message and was able to decode the message. Anyone who sees a message without having a key will only see an irregular arrangement of letters.
Public Key Encryption. This encryption uses a combination of private key and public key. The private key is only known to your computer, while the public key is assigned by your computer to any computer that wants to communicate securely. To decode encrypted messages, the computer must use the public key provided by your computer and its own private key.