Big God gives you the analysis of the difference between HTTPS and HTTP

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Today, when doing Yahoo, found that using third-party tools to intercept the client and the service side of the communication, has not encountered this situation, looked carefully, its URL request based on HTTPS, GG found the original HTTPS protocol and HTTP has a great difference. Overall, HTTP is more efficient and HTTPS security is higher.

First talk about what is https:

HTTPS (Secure hypertext Transfer Protocol) Secure Hypertext Transfer Protocol It is a secure communication channel that is based on HTTP development and is used to exchange information between client computers and servers. It uses Secure Sockets Layer (SSL) for information exchange, which simply means that it is a secure version of HTTP. It is developed by Netscape and built into its browser to compress and decompress data and return the results that are sent back on the network. HTTPS actually applies the Netscape secure full Socket Layer (SSL) as a sub-layer of the HTTP application layer. (HTTPS uses port 443 instead of using port 80来 and TCP/IP to communicate like HTTP.) SSL uses 40-bit keywords as the RC4 stream encryption algorithm, which is appropriate for the encryption of business information. HTTPS and SSL support use of the digital authentication of the number, and if necessary, the user can confirm who the sender is.

The difference between HTTPS and http:

The HTTPS protocol requires a certificate to be applied to the CA, and the general free certificate is very small and requires a fee. HTTP is a Hypertext Transfer Protocol, the information is clear-text transmission, HTTPS is a security SSL encryption transport protocol HTTP and HTTPS using a completely different connection mode with the port is not the same, the former is 80, the latter is 443.

HTTP connection is very simple, is a stateless HTTPS protocol is built by the SSL+HTTP protocol can be encrypted transmission, authentication network protocol than the HTTP protocol security HTTPS solution problem:

1. The problem of trusting the host. Server with HTTPS must request a certificate from the CA that is used to certify the server's purpose type. The client trusts the secondary host only when the certificate is used for the corresponding server. So at present, all the banking system website, the key part of the application is HTTPS. The client trusts the host by trusting the certificate. In fact, this is inefficient, but banks are more focused on security. This does not make any sense to us, our server, the use of certificates regardless of their own issue or from the public place issue, the client is one of our own, so we will certainly trust the server.

2. Disclosure and tampering of data in the course of communication

HTTPS in the general sense is that the server has a certificate.

• A) The main purpose is to ensure that server is the server he claims to be. This is the same as the 1th.
• b) All communication between the server and the client is encrypted. I. Specifically, the client generates a symmetric key that is exchanged through the server's certificate. The handshake process in the general sense. II. All information exchanged is encrypted. A third party, even if intercepted, does not make any sense. Because he doesn't have a key. Of course, there's no point in tampering.

In the case of a small client requirement, the client must also have a certificate.

• A) Here the client certificate, in fact, similar to the personal information, in addition to the user name/password, there is a CA authenticated identity. Should be a personal certificate in general, others cannot emulate, all of which can further confirm their identity.
• b) Currently a small number of personal banking Professional Edition is this practice, the specific certificate may be to take a USB flash drive as a backup carrier. Like I used the Bank of communications online banking is the way to take it. HTTPS must be cumbersome. A) originally a simple HTTP protocol, a get a response. Because HTTPS is required to also encrypt the key and confirm the encryption algorithm. A single handshake requires 6/7 round trips. I. In any application, excessive round trip will definitely affect performance. b) Then the specific HTTP protocol, each response or request, requires the client and the server to encrypt/decrypt the contents of the session. I. Although symmetric encryption/decryption efficiency is high, but still consumes too much CPU, for this there is a dedicated SSL chip. If the CPU signal is low, it will certainly degrade performance, thus not serve more requests.

Description of SSL:

SSL is a security-confidentiality protocol presented by Netscape companies in browsers such as Internet Explorer, Netscape Navigator, and Web servers such as Netscape Enterprise server for Netscape, ColdFusion server and so on) to construct a secure channel for data transmission, SSL runs above the TCP/IP layer, under the application layer, to provide encrypted data channel for the application, it uses encryption algorithms such as RC4, MD5, and RSA, using 40-bit keys, For encryption of business information. At the same time, Netscape company developed the HTTPS protocol and built in its browser, HTTPS is actually SSL over HTTP, it uses the default port 443, instead of using port 80来 and TCP/IP to communicate like HTTP. The HTTPS protocol uses SSL to encrypt the original data in the sender, then decrypt the receiver, the encryption and decryption needs the sender and the receiver by exchanging the common known key, so the transmitted data is not easy to be intercepted and decrypted by the network hacker. However, the encryption and decryption process requires a large amount of overhead on the system, severely reducing the performance of the machine, and the relevant test data indicates that the efficiency of data transfer using the HTTPS protocol is only one-tenth of the HTTP protocol. If for security purposes, all Web applications of a website are SSL-enabled to encrypt and transmit using the HTTPS protocol, then the performance and efficiency of the site will be greatly reduced, and it is not necessary because generally not all data are required to be so high level of security, so, We only need to use the HTTPS protocol for interactive processing involving confidential data, so that we can get the best of both worlds. In short, do not need to use the place of HTTPS, try not to use.

Big God gives you the analysis of the difference between HTTPS and HTTP (go)