**> https certificates are what?
HTTPS certificate is actually one kind of transport protocol. HTTP protocol to transmit the data are not encrypted, which means that users fill in passwords, account numbers, transaction records and other confidential information are expressly at any time may be leaked, stolen, tampered with, thereby take advantage of ***, so use HTTP protocol for transmitting private information very unsafe.
Use HTTPS encryption protocol access can be activated (SSL protocol (What is SSL protocol), this way you can achieve high strength two-way encrypted transmission, prevent information being leaked at the time of data transmission.
Simply speaking, HTTPS = HTTP + SSL, that is, HTTPS is the secure version of HTTP
SSL certificate is actually CA public key authentication mechanism for users, including signature and expiration date information, user information public, public keys, authority electronic visa authorities.
CA (Certification Authority, Certificate Authority) organization, is to undertake a third-party inspection of the legitimacy of public authority, responsible for specifying policies, steps to verify the user's identity, and the SSL certificate is signed to ensure the identity of the certificate holder and ownership of the public key.
CA user organization using the public key for each issuing an SSL certificate, the role of SSL certificate is a personal / corporate listed in the certificate to prove the legal owner of the public key listed in the certificate.
CA digital signature allows institutions *** can not forge and tampering with a certificate.
After installing SSL Web site certificate to show the form of a browser (the following picture to EV SSL Certificates as an example):
Why websites need to apply SSSL certificate?
(1) SSL certificate may be encrypted so as not to be leaked sensitive information
The main reason to use SSL certificate to protect sensitive information sent over the Internet can be encrypted to prevent important data from being leaked.
This is important, because you transfer information between your computer and a server on the Internet,
if the SSL certificate encryption is not used, you pass any information you are likely to be accessible to third parties,
including your credit card number, user name and password, and other sensitive information
. With SSL certificate, you can guarantee everyone can not read the information, which can protect data against information *** or bad faith of the people of the infringement.(2) SSL certificates can provide authentication to prevent phishing sites
In addition to encryption, SSL certificates can provide authentication.
This means that you can ensure that the information is sent to the correct server, do not worry about someone stealing your information.
Effectively prevent third parties masquerading as your website and deceive your users, access to personal information, resulting in large or small loss.
The SSL certificate is issued by a CA trusted authority, and will strictly verify the information business / organization applying for the certificate.So, choose a trusted CA SSL certificate issued by the agency is very important,
the CA will only issue SSL certificates verify all kinds of information, and EV SSL certificates require more information than other verification certificate.(3) SSL certificates increase trust, eliminate browser "unsafe" prompt
Earlier in Google browser blow http site, the SSL certificate is not installed in the http site, suggesting that "unsafe" logo,
as shown below, very much affect the user experience, the loss of a large number of website traffic.
SSL certificate installed sites can be displayed in the Web browser address bar, small green lock icon in the address bar green,
EV SSL certificates can also display the company / organization name. To ensure that visitors know that the connection is protected, you can be assured.
This means that when visitors see these tips will be more likely to trust your website.
And you can view the information issued by the CA mechanism, in order to provide more confidence for your customers.（4）有利于seo关键词排名
谷歌、百度等浏览器，明确表示对安装SSL证书的网站进行优先暂时排名的权利，
因此除非网站安装了SSL证书，否则网站将很难在搜索引擎靠前的位置找到，从而影响网站的流量和收入。
如何选择SSL证书？
首先考虑自己拥有的域名数量，单个域名就选择单域名SSL证书，多个主域就现在多域名证书，多个同一个域名的子域就现在通配符证书。
其次考虑验证方式，如果是个人类网站博客的话，只能选择DV SSL证书，因为OV/EV需要验证组织信息，个人无法提供这些信息。企业用户的话，安信证书建议选择OV、EV SSL证书，更加的可信赖，而且EV SSL证书可在浏览器地址栏显示企业名称，有利于企业品牌的宣传，给用户信赖感。
1、个人网站：如果经营的是小型的个人网站，是个人站长或者自媒体，需要HTTPS但是对于网站信誉度没有过高的要求，那么就可以选择域名验证证书(DV)。DV证书签发速度快，价格便宜，通常十分钟内就可完成签发，无需复杂的网站身份验证过程，支持HTTPS和安全挂锁标志，性价比极高。
2、企业网站：如果经营的是普通企业类网站，涉及注册、登录、会员中心等页面，那么推荐使用企业型SSL证书（OV）或增强型SSL证书（EV）。这两种证书都要求对网站所属者的身份进行认证，能够证明网站的真实身份，杜绝钓鱼网站，并且更好得保护访客的个人信息安全。EV证书会使网站地址栏变绿，利于品牌推广，更容易赢得客户信赖。
3、电商网站：对于电商类网站来说，用户的信息安全和网站的品牌形象是购买SSL证书的关键因素。电商类网站涉及交易支付、客户隐私信息以及账号密码等，需要更高一级的加密。并且电商类网站访问量较大，品牌形象较为重要，推荐使用专业版企业型SSL证书（OV）或专业版增强型SSL证书（EV）。
4, financial website: financial securities, banking, third-party payment sites typically require the highest level of security, not only related to the user's private information, credit card information, payment security, but for the true identity of the site has a high demand for standards . Enhanced Extended Validation certificates (EV) using the most appropriate financial website, EV SSL certificate means the certificate issued in compliance with global standards, strict site authentication, is the highest level of security of SSL certificates. And after the installation of EV certificates, the browser address bar green visual display unit and a Chinese name, safe and reliable at a glance
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