{"id":12374418,"date":"2026-03-17T15:45:33","date_gmt":"2026-03-17T07:45:33","guid":{"rendered":"https:\/\/www.likacloud.com\/knowledge\/%e4%bb%8e%e5%85%a5%e9%97%a8%e5%88%b0%e7%b2%be%e9%80%9a%ef%bc%9a%e5%85%a8%e6%96%b9%e4%bd%8d%e8%a7%a3%e6%9e%90ssl%e8%af%81%e4%b9%a6%e7%9a%84%e4%bd%9c%e7%94%a8%e3%80%81%e7%b1%bb%e5%9e%8b%e4%b8%8e\/"},"modified":"2026-03-17T15:51:20","modified_gmt":"2026-03-17T07:51:20","slug":"ssl-certificate-guide-types-application-deployment-tutorial","status":"publish","type":"knowledge_post","link":"https:\/\/www.likacloud.com\/en\/knowledge\/ssl-certificate\/ssl-certificate-guide-types-application-deployment-tutorial\/","title":{"rendered":"From Beginner to Expert: A Comprehensive Guide to the Role, Types of SSL Certificates, and How to Apply for and Deploy Them"},"content":{"rendered":"

In today's internet environment, website security has become an essential foundation that cannot be ignored. A secure and reliable website not only protects user data but also earns the trust of visitors. One of the core technologies for achieving this goal is the SSL\/TLS protocol and its digital credentials\u2014the SSL certificate. It acts as the website's \u201cdigital identity card\u201d and \u201csecure encryption envelope,\u201d establishing an encrypted communication channel between the user's browser and the website server.<\/p>\n\n\n\n

The core role and value of an SSL certificate<\/h2>\n\n\n\n

An SSL certificate is far more than just a \u201clittle lock\u201d icon that appears in the address bar. It represents a comprehensive security mechanism that provides multiple layers of protection for both websites and users.<\/p>\n\n\n\n

Implement data encryption transmission<\/h3>\n\n\n\n

When a user visits a website that has an SSL certificate deployed, their browser establishes an encrypted connection with the server through a process known as a \u201chandshake.\u201d All data transmitted between the two parties thereafter\u2014including login credentials, credit card numbers, personal information, and chat content\u2014is encrypted. Even if the data is intercepted by a third party during transmission, it cannot be decrypted without the corresponding private key, effectively preventing information theft and man-in-the-middle attacks.<\/p>\n

Recommended Reading Master SSL Certificates: A Comprehensive Analysis of Their Types, Application Processes, and Website Security Configuration<\/a>\u3002<\/p>\n\n\n\n\n

Verify the true identity of the website<\/h3>\n\n\n\n

SSL certificates are issued by trusted third-party organizations known as Certificate Authorities (CAs). Before issuing a certificate, CAs conduct a thorough verification of the applicant\u2019s identity. As a result, when a user visits a website with a valid SSL certificate, the browser can confirm that the website they are accessing is indeed the legitimate entity it claims to be, and not a phishing or counterfeit site. This helps to build users\u201c trust in the website.<\/p>\n\n

\r\n\t\r\n\t\t\r\n\t\r\n\t
\r\n\t\t
\r\n\t\t\t\r\n\t\t\t
\r\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"Bluehost\r\n\t\t\t\t\t\t\t\t\t\r\n\t\t\t<\/div>\r\n\t\t\t\r\n\t\t\t\r\n\t\t\t
\r\n\t\t\t\t
\r\n\t\t\t\t\tBluehost SSL Certificate<\/strong>\r\n\t\t\t\t\t\t\t\t\t<\/div>\r\n\t\t\t<\/div>\r\n\t\t<\/div>\r\n\t\t\t\tBlueHost SSL Certificates offer 1-2 year extension options, support for RSA or ECC algorithms, key lengths up to 4096 bits, and up to $1.75 million in protection.<\/span>\r\n\t\t\t\t
\r\n\t\t\t\r\n\t\t\t\t\t\t\r\n\t\t\t \r\n\t\t\t
\r\n\t\t\t\t\t\t\t\t
From $7.49 USD per month<\/div>\r\n\t\t\t\t\t\t\t\t\t\t\t\tAccess to Bluehost SSL Certificates \u2192<\/a>\r\n\t\t\t\t\t\t\t<\/div> \r\n\t\t<\/div>\r\n\t<\/div>\r\n\t\t\r\n\t\r\n\t
\r\n\t\t
\r\n\t\t\t\r\n\t\t\t
\r\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"hosting.com\r\n\t\t\t\t\t\t\t\t\t\r\n\t\t\t<\/div>\r\n\t\t\t\r\n\t\t\t\r\n\t\t\t
\r\n\t\t\t\t
\r\n\t\t\t\t\thosting.com SSL Certificate<\/strong>\r\n\t\t\t\t\t\t\t\t\t<\/div>\r\n\t\t\t<\/div>\r\n\t\t<\/div>\r\n\t\t\t\tAffordable DV, OV, EV SSL certificates, up to 256-bit encryption, 5 ~ 1 million USD protection amount, 24\/7 support<\/span>\r\n\t\t\t\t
\r\n\t\t\t\r\n\t\t\t\t\t\t\r\n\t\t\t \r\n\t\t\t
\r\n\t\t\t\t\t\t\t\t
From $2.5 USD per month<\/div>\r\n\t\t\t\t\t\t\t\t\t\t\t\tVisit hosting.com SSL Certificates \u2192<\/a>\r\n\t\t\t\t\t\t\t<\/div> \r\n\t\t<\/div>\r\n\t<\/div>\r\n\t\t\r\n<\/div>\r\n\r\n\r\n\n\n\n\n\n\n\n

Improving search engine rankings and user trust<\/h3>\n\n\n\n

Major search engines such as Google have long considered HTTPS to be a positive factor in determining search rankings. Websites that use HTTPS generally receive preferential display in search results. Additionally, modern browsers (such as Chrome and Safari) clearly mark non-HTTPS websites as \u201cinsecure,\u201d which significantly increases the user bounce rate. Conversely, the green security lock and the \u201csecure\u201d indicator directly enhance users\u2019 confidence while browsing and their willingness to complete transactions or take other actions on the website.<\/p>\n\n\n\n

The main types of SSL certificates and their applicable scenarios<\/h2>\n\n\n\n

Based on the level of validation and the features provided, SSL certificates are mainly divided into the following categories to meet the needs of websites of different sizes and types.<\/p>\n\n\n\n

Domain Validation Certificate<\/h3>\n\n\n\n

DV (Domain Validation) certificates are the type of certificate with the lowest level of verification and the fastest issuance process. The Certificate Authority (CA) only verifies the applicant's ownership of the domain name, typically by checking the domain name resolution records or confirming a specified email address. They are ideal for personal websites, blogs, testing environments, or any situation where only basic encryption is required. The main advantages of DV certificates are their low cost and immediate issuance.<\/p>\n\n\n\n

Organizational validation type certificate<\/h3>\n\n\n\n

OV (Organizational Validation) certificates offer a higher level of trust than DV (Domain Validation) certificates. In addition to verifying the ownership of the domain name, the Certificate Authority (CA) also confirms the actual existence of the applying organization by checking legal documents such as business licenses. The certificate details include the name of the applying company. These certificates are suitable for corporate websites, organizational portals, and other commercial websites that need to demonstrate the credibility of the entity behind them.<\/p>\n

Recommended Reading SSL Certificate Overview: How It Works, Type Selection, and HTTPS Configuration Guide<\/a>\u3002<\/p>\n\n\n\n\n

Extended Validation Certificate<\/h3>\n\n\n\n

EV certificates are the most rigorously verified and have the highest level of trust. Certification Authorities (CAs) follow strict review processes, which include verifying the legal, physical, and operational existence of the organization. Browsers also give EV certificates special prominence in their display: the company name is displayed in green directly in the address bar. This used to be the standard configuration for websites in industries with extremely high trust requirements, such as finance, e-commerce, and large enterprises. Although the user interfaces of modern browsers have changed, the strict review standards that underlie them remain among the highest levels of trust.<\/p>\n\n\n\n

Multiple domain and wildcard certificates<\/h3>\n\n\n\n

All three types of certificates can be further subdivided based on their coverage scope. \nA single-domain certificate protects only one specific domain name (e.g., www.example.com). \nA multi-domain certificate can protect multiple completely unrelated domain names within a single certificate (e.g., example.com, example.net, shop.othersite.com). \nA wildcard certificate protects a primary domain name and all its subdomains at the same level (e.g., *.example.com, which can cover blog.example.com, shop.example.com, mail.example.com, etc.), making it ideal for businesses with multiple subdomains.<\/p>\n\n\n\n

How to apply for and obtain an SSL certificate<\/h2>\n\n\n\n

The process of obtaining an SSL certificate is clear and mainly consists of several steps.<\/p>\n\n\n

\n\n
\n UltaHost SSL Certificate<\/strong>\n
DV, EV, OV certificates, up to $1,750,000 USD coverage, unlimited sub-domains, iOS and Android apps, discounted 20% per month, $15.95 USD onwards, 30-day money-back guarantee<\/div>\n <\/div>\n\n
\n \n \n \"SSL\n \n \n <\/a>\n \n \n Visit UltaHost <\/a>\n <\/div>\n <\/div>\n\n \n\n\n\n\n\n\n

Step 1: Generate a certificate signing request<\/h3>\n\n\n\n

On your server (such as Nginx, Apache, Tomcat, etc.), the first step is to generate a key pair (private key and public key) as well as a Certificate Signing Request (CSR) file. The CSR file contains your public key, domain name, company information, and other relevant details. The private key must be kept securely on the server and must not be disclosed under any circumstances.<\/p>\n\n\n\n

Step 2: Select a CA (Certificate Authority) and submit the application.<\/h3>\n\n\n\n

Based on your requirements (verification type, brand, budget, etc.), select a reputable CA (Certificate Authority) or its agent. Submit your application on their website, and paste the content of the generated CSR (Certificate Signing Request) file in the designated location. For OV (Organizational Validation) and EV (Extended Validation) certificates, you will also need to submit the required organizational certification documents.<\/p>\n\n\n\n

Step 3: Complete the domain name\/organization verification.<\/h3>\n\n\n\n

The CA will initiate the verification process based on the type of certificate you have applied for. For DV (Domain Validation) certificates, you may need to set up specified DNS records or receive verification emails to confirm control of the domain name. For OV (Organizational Validation) or EV (Extended Validation) certificates, the CA may verify the organization\u2019s information through phone calls, third-party databases, or other means.<\/p>\n

Recommended Reading A Complete Guide to SSL Certificates: How to Select, Install, and Verify Website Security Encryption<\/a>\u3002<\/p>\n\n\n\n\n

Step 4: Issue and download the certificate<\/h3>\n\n\n\n

After the verification is successful, the CA will issue the certificate. You can download the certificate package, which includes the server certificate (and possibly intermediate certificates) from the CA\u2019s console. The certificate files typically have extensions such as .crt, .cer, or .pem.<\/p>\n\n\n\n

Free Certificate Options<\/h3>\n\n\n\n

\u5bf9\u4e8e\u4e2a\u4eba\u6216\u9884\u7b97\u6709\u9650\u7684\u7528\u6237\uff0cLet\u2018s Encrypt\u662f\u4e00\u4e2a\u4f18\u79c0\u7684\u514d\u8d39CA\u9009\u62e9\u3002\u5b83\u63d0\u4f9b\u81ea\u52a8\u7b7e\u53d1\u7684DV\u8bc1\u4e66\uff0c\u6709\u6548\u671f90\u5929\uff0c\u53ef\u4ee5\u901a\u8fc7Certbot\u7b49\u5de5\u5177\u5b9e\u73b0\u81ea\u52a8\u5316\u7eed\u671f\uff0c\u5b8c\u5168\u514d\u8d39\u4e14\u6d41\u7a0b\u9ad8\u5ea6\u81ea\u52a8\u5316\uff0c\u6781\u5927\u5730\u63a8\u52a8\u4e86HTTPS\u7684\u666e\u53ca\u3002<\/p>\n\n\n\n

Deploying and configuring SSL certificates on a server<\/h2>\n\n\n\n

After obtaining the certificate file, the next crucial step is to deploy it correctly on your web server. The following examples illustrate this process for the commonly used Nginx and Apache servers.<\/p>\n\n\n\n

Nginx server configuration<\/h3>\n\n\n\n

Please use the server certificate you have downloaded (which is usually named\u2026) your_domain.crt<\/code>) and the private keyyour_domain.key<\/code>Upload it to a secure directory on the server (for example, \/etc\/ssl\/<\/code>Then, edit your website\u2019s Nginx configuration file (which is usually located in\u2026) \/etc\/nginx\/sites-available\/<\/code> (Next.)
\nWhat needs to be done is based on the existing\u2026 listen 80;<\/code> Next to the existing server block, add a new server block to listen on port 443 (the default port for HTTPS). The core configuration instructions include specifying the paths for the SSL certificate and private key, as well as selecting the appropriate SSL protocol and encryption suite to enhance security. Once the configuration is complete, proceed with\u2026 nginx -t<\/code> Test the configuration syntax; once it is confirmed to be correct, proceed with the next step. systemctl reload nginx<\/code> Reload the configuration.<\/p>\n\n\n\n

Apache server configuration<\/h3>\n\n\n\n

For Apache servers, you also need to upload the certificate and private key files. Next, edit your virtual host configuration file (for example,...). \/etc\/apache2\/sites-available\/your-site.conf<\/code>\uff09\u3002
\nAfter enabling the SSL module, add it to the virtual host configuration. SSLEngine on<\/code> Instructions, and proceed accordingly. SSLCertificateFile<\/code> and SSLCertificateKeyFile<\/code> The instructions specify the paths for the certificate file and the private key file respectively. It is also necessary to configure the enhanced SSL protocol. After saving the settings, proceed with the use. apachectl configtest<\/code> Test the system, and then restart the Apache service.<\/p>\n\n\n\n

Forced HTTPS redirection and HSTS (HTTP Strict Transport Security)<\/h3>\n\n\n\n

After the deployment is complete, to ensure that all traffic is directed through the secure HTTPS channel, you should configure a 301 redirect from HTTP to HTTPS. This can be achieved by adding a rewrite rule in the server\u2019s listening block on port 80.
\nGoing a step further, you can enable HSTS (HTTP Strict Transport Security). By including the appropriate header in your responses, you instruct browsers to use HTTPS for all visits to the site for a specified period of time (for example, one year). This can effectively prevent SSL stripping attacks. However, please be cautious when enabling HSTS: make sure it is only done after you have confirmed that HTTPS is working correctly, as a configuration error could result in users being unable to access the site for an extended period.<\/p>\n\n\n\n

Post-installation verification<\/h3>\n\n\n\n

After deployment, be sure to access your HTTPS website using a browser to check whether the lock icon in the address bar is displayed correctly. Click on the icon to view the certificate details and verify that they match the information you provided. It is also highly recommended to use online SSL testing tools (such as SSL Labs\u2019 SSL Test) to perform a comprehensive security assessment of your configuration. These tools will identify potential weaknesses in your setup, such as insecure protocols or weak encryption algorithms.<\/p>\n\n\n\n

summarize<\/h2>\n\n\n\n

SSL certificates are essential tools for ensuring the security of online communications and building user trust. ranging from basic DV certificates to highly secure EV certificates, and from single-domain certificates to wildcard certificates, the wide variety of options available can meet the needs of different scenarios. The application process has become increasingly simplified and automated, especially with the widespread availability of free certificates, which has significantly lowered the barriers to enabling HTTPS for websites. A successful deployment depends not only on the installation but also on the correct configuration and ongoing maintenance, including enforcing HTTPS redirects, enabling HSTS (HTTP Strict Security Transport), and regularly renewing the certificates. Embracing HTTPS is not only about keeping up with technological trends but also about demonstrating a responsible attitude towards user security and the reputation of one\u2019s own brand.<\/p>\n\n\n\n

FAQ Frequently Asked Questions<\/h2>\n\n\n\n

Are SSL certificates and TLS certificates the same thing?<\/h3>\n\n\n\n

Essentially, they refer to the same technology. SSL (Secure Sockets Layer) is an older version of the protocol, and its successor is the more secure and modern TLS (Transport Layer Security) protocol. However, due to historical convention, the term \u201cSSL certificate\u201d is still widely used. Therefore, the SSL certificates available on the market today actually support the TLS protocol.<\/p>\n\n\n\n

What is the difference between a free SSL certificate and a paid one?<\/h3>\n\n\n\n

\u4e3b\u8981\u533a\u522b\u5728\u4e8e\u9a8c\u8bc1\u7ea7\u522b\u3001\u529f\u80fd\u3001\u4fdd\u969c\u548c\u670d\u52a1\u3002\u514d\u8d39\u8bc1\u4e66\uff08\u5982Let\u2018s Encrypt\uff09\u901a\u5e38\u662fDV\u8bc1\u4e66\uff0c\u4ec5\u9a8c\u8bc1\u57df\u540d\u6240\u6709\u6743\uff0c\u9002\u5408\u4e2a\u4eba\u6216\u975e\u5546\u4e1a\u9879\u76ee\u3002\u4ed8\u8d39\u8bc1\u4e66\u63d0\u4f9bOV\u3001EV\u7b49\u66f4\u9ad8\u7ea7\u522b\u7684\u9a8c\u8bc1\uff0c\u80fd\u5c55\u793a\u516c\u53f8\u4fe1\u606f\uff0c\u63d0\u5347\u4fe1\u4efb\u5ea6\uff1b\u901a\u5e38\u63d0\u4f9b\u66f4\u9ad8\u7684\u4fdd\u4fee\u91d1\u989d\uff08\u5982\u767e\u4e07\u7f8e\u5143\u7ea7\u4fdd\u969c\uff09\uff0c\u5728\u8bc1\u4e66\u88ab\u76d7\u6216\u8bef\u7b7e\u53d1\u5bfc\u81f4\u635f\u5931\u65f6\u63d0\u4f9b\u8d54\u507f\uff1b\u5e76\u4e14\u62e5\u6709\u4e13\u4e1a\u7684\u6280\u672f\u652f\u6301\u670d\u52a1\u3002<\/p>\n\n\n\n

Why does the browser still display a \u201cnot secure\u201d message after the certificate has been deployed?<\/h3>\n\n\n\n

There are several possible reasons: \n1. The website page contains resources loaded using the HTTP protocol (such as images, JavaScript, and CSS files), and all resource links need to be changed to HTTPS. \n2. The certificate chain is incomplete, and the server has not properly configured the intermediate certificate. \n3. The certificate's domain name does not match the domain name currently being accessed. \n4. The certificate has expired. \nYou need to troubleshoot based on the specific error messages provided by the browser.<\/p>\n\n\n\n

How often does an SSL certificate need to be renewed?<\/h3>\n\n\n\n

\u76ee\u524d\uff0c\u4e3b\u6d41CA\u7b7e\u53d1\u7684SSL\u8bc1\u4e66\u6700\u957f\u6709\u6548\u671f\u4e3a398\u5929\uff08\u7ea613\u4e2a\u6708\uff09\uff0c\u8fd9\u662f\u884c\u4e1a\u6807\u51c6\u59d4\u5458\u4f1a\u5f3a\u5236\u89c4\u5b9a\u7684\u3002\u514d\u8d39\u8bc1\u4e66\u5982Let\u2018s Encrypt\u6709\u6548\u671f\u66f4\u77ed\uff0c\u4e3a90\u5929\u3002\u56e0\u6b64\uff0c\u60a8\u9700\u8981\u5b9a\u671f\u5728\u8bc1\u4e66\u8fc7\u671f\u524d\u8fdb\u884c\u7eed\u671f\u64cd\u4f5c\uff0c\u5426\u5219\u8fc7\u671f\u540e\u7f51\u7ad9\u8bbf\u95ee\u5c06\u56e0\u5b89\u5168\u8b66\u544a\u800c\u4e2d\u65ad\u3002\u5efa\u8bae\u8bbe\u7f6e\u81ea\u52a8\u7eed\u671f\u6216\u63d0\u524d\u7eed\u671f\u63d0\u9192\u3002<\/p>\n\n\n\n

Can an SSL certificate be used on multiple servers?<\/h3>\n\n\n\n

Sure, but the approach needs to be carefully considered. If you have multiple servers providing the same service (such as a load-balanced cluster), you can deploy the same certificate and private key to each server. An even better option is to use a type of certificate that supports multi-server deployment (for example, some certificates allow you to specify multiple server IP addresses), or use specialized certificate management tools to distribute and deploy the certificates. The most important thing is to ensure that the private key is managed securely.<\/p>","protected":false},"excerpt":{"rendered":"

This article systematically introduces the role of SSL certificates in data encryption, identity authentication, and improving search rankings. It compares in detail certificate types such as DV, OV, EV, and multi-domain certificates, and provides a complete application and deployment guide from generating a CSR to completing the verification, including the selection of free certificates.<\/p>","protected":false},"author":7,"featured_media":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"tags":[326,11,416,319,338],"knowledge_category":[277],"class_list":["post-12374418","knowledge_post","type-knowledge_post","status-publish","hentry","tag-https-guide","tag-ssl-certificate","tag-encrypted-transmission","tag-website-security","tag-cybersecurity","knowledge_category-ssl-certificate"],"acf":{"site_seo_keywords":"SSL\u8bc1\u4e66,HTTPS\u52a0\u5bc6,SSL\u8bc1\u4e66\u7533\u8bf7,SSL\u8bc1\u4e66\u7c7b\u578b,SSL\u90e8\u7f72\u6559\u7a0b,\u7f51\u7ad9\u5b89\u5168\u8bc1\u4e66,\u901a\u914d\u7b26SSL\u8bc1\u4e66"},"_links":{"self":[{"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/knowledge_posts\/12374418","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/knowledge_posts"}],"about":[{"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/types\/knowledge_post"}],"author":[{"embeddable":true,"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/users\/7"}],"version-history":[{"count":0,"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/knowledge_posts\/12374418\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/media?parent=12374418"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/tags?post=12374418"},{"taxonomy":"knowledge_category","embeddable":true,"href":"https:\/\/www.likacloud.com\/en\/wp-json\/wp\/v2\/knowledge_category?post=12374418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}