1. http protocol and https protocol
http protocol: Hypertext transfer protocol is the most widely used protocol on the Internet. It is based on the TCP/IP communication protocol to transfer information, and is used to transfer hypertext from the WWW server to the local browser.
https protocol: we can think of it as an http protocol with security as the goal. The SSL/TSL layer is added on the basis of the http protocol to ensure the security and integrity of data transmission.
Here to talk about the composition of the agreement
2. Encryption of https protocol
Plaintext and key
Symmetric key encryption: use the same key for encryption and decryption
Asymmetric key encryption: use different keys for encryption and decryption
Digital signature: It is a special encryption check code attached to the message. When the digital signatures are inconsistent, it means that the data has probably been tampered with.
Digital certificate: An accreditation certificate issued by an authority that contains some authentication information.
3. The difference between http protocol and https protocol
| http protocol | https protocol |
|---|---|
| Port: 80 | Port: 443 |
| Clear text transmission | Encrypted transmission |
| Simple connection, stateless | Network protocol capable of encrypted transmission and identity authentication |
4. Disadvantages of https protocol
1. The https handshake time is longer, which will extend the page loading time by 50% and increase the power consumption by 10% to 20%.
2. https caching is not as efficient as http.
3. SSL certificates need to be purchased and are expensive.
4. SSL needs to bind ip and cannot support one ip to bind multiple domain names.
5. Although https has the function of encryption, there are still no effective defensive measures against hacker attacks and server interception.
ps: This article is organized by myself, and I try to repeat it in my own words. Compared with rote memorization, I want to remember knowledge through understanding. There may be missing things. If there are errors, I hope everyone can point them out. Corrected immediately.