Data Encryption and Privacy Protection<\/h3>\n\n\n\n
Another core function of an SSL certificate is to enable data encryption. It achieves this by combining asymmetric and symmetric encryption methods to negotiate and generate a unique session key between the client and the server. All data transmitted between them thereafter (such as login credentials, credit card numbers, personal information, and chat records) is encrypted using this key. Even if the data is intercepted during transmission, the attacker will only receive a bunch of unreadable ciphertext, thereby ensuring the confidentiality of the information.<\/p>\n\n
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\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![\"hosting.com](\"https:\/\/www.likacloud.com\/wp-content\/uploads\/2025\/12\/20251227070008.webp\" "\\"\\"")
\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\tData Integrity Assurance<\/h3>\n\n\n\n
In addition to encryption, the SSL\/TLS protocol also ensures the integrity of data through Message Authentication Codes (MACs). This means that if the data is altered during transmission, the recipient can immediately detect such changes, thereby preventing malicious modifications to the data by attackers using man-in-the-middle attacks.<\/p>\n\n\n\n
The main types of SSL certificates and how to choose them<\/h2>\n\n\n\n
Based on the level of validation and the scope of functionality they cover, SSL certificates are mainly divided into the following types, each suitable for different business scenarios and security requirements:<\/p>\n\n\n\n
Domain Validation Certificate<\/h3>\n\n\n\n
The DV (Domain Validation) certificate is the most basic type of SSL certificate, and it is issued the fastest. The certification authority (CA) only verifies the applicant\u2019s ownership of the domain name (usually through email or DNS resolution records), without verifying the actual identity of the company or organization. As a result, the certificate only contains information about the domain name.
\nThese certificates are inexpensive or even free, making them suitable for personal blogs, small websites, or testing environments. They provide basic encryption capabilities, but they cannot display detailed corporate information to establish a high level of trust with users.<\/p>\n\n\n\n
Organizational validation type certificate<\/h3>\n\n\n\n
The verification process for OV (Organizational Validation) certificates is more stringent. The Certificate Authority (CA) not only verifies the ownership of the domain name but also confirms the actual existence of the applying company, including details such as the company name, address, and phone number. This information is included in the certificate details for users to review.
\nOV certificates significantly enhance the credibility of a website and are suitable for corporate official websites, general e-commerce platforms, as well as online service platforms that need to demonstrate the identity of a legitimate entity.<\/p>\n
Recommended Reading Comprehensive Analysis of SSL Certificates: From Principles to Installation, Solve Your Website's Security and Trust Issues in 10 Minutes<\/a>\u3002<\/p>\n\n\n\n\n EV certificates provide the highest level of verification and trust. Certification Authorities (CAs) follow the most stringent review processes and adhere to globally unified standards to thoroughly verify the legal and physical existence of the organizations. Websites that have deployed EV certificates will display the company name in green directly in the address bar of most major browsers, in addition to the security lock icon. In addition to the level of validation, certificates can also be classified based on the number of domains they cover. A single-domain certificate protects only one specific domain (for example, www.example.com). Multi-domain certificates allow the protection of multiple completely unrelated domains within a single certificate. Wildcard certificates, on the other hand, can protect a primary domain and all its subdomains at the same level (for example, *.example.com), making them ideal for companies with a large number of sub-sites, as they offer more convenient and efficient management.<\/p>\n\n\n\n The working mechanism of an SSL certificate is based on the SSL\/TLS protocol, and the core process is known as the \u201cSSL handshake.\u201d This is a series of complex yet efficient message exchanges that occur before the client and server establish a formal, encrypted communication channel.<\/p>\n\n\n 1. Client Greeting: The client (browser) sends a \u201cClientHello\u201d message to the server, which includes the TLS version supported by the client, a list of supported encryption suites, and a random number. At this point, the secure channel has been established. All application-layer data (HTTP data) will subsequently be encrypted using this efficient symmetric session key, ensuring a balance between communication security and performance.<\/p>\n\n\n\n Deploying an SSL certificate for a website is a systematic process that primarily includes certificate application, verification, installation, and subsequent maintenance.<\/p>\nExtended Validation Certificate<\/h3>\n\n\n\n
\nThis type of certificate is the preferred choice for financial institutions, large e-commerce platforms, government agencies, and other organizations with extremely high requirements for security and trust. It can significantly reduce users' concerns about phishing websites.<\/p>\n\n\n\nClassification by functional coverage: Single-domain, multi-domain, and wildcard certificates<\/h3>\n\n\n\n
The working principle and handshake process of the SSL\/TLS protocol<\/h2>\n\n\n\n
![\"SSL](\"https:\/\/www.likacloud.com\/wp-content\/uploads\/2025\/12\/20251227020448.webp\" "\\"\\"")
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\n <\/a>\n \n \n Visit UltaHost <\/a>\n <\/div>\n <\/div>\n\n \n\n\n\n\n\n\nDetailed explanation of the handshake process<\/h3>\n\n\n\n
\n2. Server Greetings and Certificates: The server responds with a \u201cServerHello\u201d message, selects a TLS version and encryption suite that are supported by both parties, and then sends its own random number. Subsequently, the server sends its SSL certificate (which contains the public key) to the client.
\n3. Certificate Verification and Key Exchange: After receiving the certificate, the client uses its built-in library of trusted CA (Certificate Authority) root certificates to verify the authenticity and validity of the server\u2019s certificate. Once the verification is successful, the client generates a \u201cpre-master key\u201d and encrypts it using the public key from the server\u2019s certificate. The encrypted pre-master key is then sent to the server.
\n4. Generating the session key and completing the handshake: The server uses its private key to decrypt the pre-master key. At this point, both the client and the server have three elements: the client\u2019s random number, the server\u2019s random number, and the pre-master key. Both parties use the same algorithm to independently generate the same \u201csession key\u201d based on these three parameters. Afterwards, they exchange a \u201cFinished\u201d message, which is encrypted using the newly generated session key, to confirm that the handshake process was successful and that the keys match.<\/p>\n\n\n\nPractical Guide to Obtaining, Installing, and Configuring SSL Certificates<\/h2>\n\n\n\n