Foreword
Network Security Four Elements
Confidentiality: prevent information from being stolen during transmission, they need to encrypt information to a certain extent
Message integrity: prevent information from being maliciously tampered with during transmission, we need to ensure the integrity of the message
Endpoint identification: the sender and the recipient should be able to confirm the other party involved in the communication process, to make sure the other party does have to communicate their claimed identity
Operational safety: organizations within the network and Internet connections will be necessary to prevent attacks from the Internet
Confidentiality and cryptology
Cryptography allows the sender can masquerade, so that an intruder can not get any information from the intercepted data
Symmetric cryptographic mechanisms, namely the communicating parties have the same password
Public key encryption, i.e. both communication parties have a pair of keys, public key encryption with the sender each other, the receiver can use its own private key to decrypt
Message integrity and digital signatures
Message integrity two important points: 1) the packet is indeed sent from party; 2) during transmission message has not been tampered
Digital Signature: encrypt the message using the private key, digital signature capabilities to complete