What is ssl?

SSL (Secure Sockets Layer) and its successor Transport Layer Security (TLS) are a security protocol that provides security and data integrity for network communications; TLS and SSL are The transport layer encrypts network connections.

Secure Socket Layer, developed by Netscape, is used to ensure the security of data transmission on the Internet. It uses data encryption (Encryption) technology to ensure that data is Transmissions on the network will not be intercepted or eavesdropped. The generally accepted specification is the 40-bit security standard. The United States has introduced a higher security standard of 128-bit, but exports are restricted. As long as I.E. or Netscape browser version 3.0 or above can support SSL.

The current version is 3.0. It has been widely used for authentication and encrypted data transmission between web browsers and servers.

The SSL protocol is located between the TCP/IP protocol and various application layer protocols, providing security support for data communication. The SSL protocol can be divided into two layers: SSL Record Protocol: It is built on a reliable transmission protocol (such as TCP) and provides support for basic functions such as data encapsulation, compression, and encryption for high-level protocols. SSL Handshake Protocol: It is built on the SSL record protocol and is used by the communicating parties to authenticate identities, negotiate encryption algorithms, and exchange encryption keys before actual data transmission begins.

Provide services

1) Authenticate users and servers to ensure data is sent to the correct client and server;

2) Encrypt data to prevent The data is stolen midway;

3) Maintain the integrity of the data and ensure that the data is not changed during the transmission process.

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