What is Secure Sockets Layer (SSL)?
SSL (Secure Sockets Layer) is a security protocol designed to establish an encrypted connection between a web server and a client (usually a web browser). Although SSL has been succeeded by TLS (Transport Layer Security), the term “SSL” is still commonly used to refer to the technology that secures internet communications.
How SSL Works
- SSL Handshake: When a browser connects to a website secured with SSL, the following steps occur:
- Connection Initiation: The browser initiates a connection to the server.
- Server Identification: The server responds by sending a copy of its SSL certificate.
- Certificate Validation: The browser validates the SSL certificate to ensure it is trustworthy.
- Encryption: Once validated, a secure, encrypted connection is established between the browser and the server, allowing safe data transmission.
- Visual Indicators: On modern browsers, secure sites use HTTPS in their URL and display a padlock icon. Clicking this icon allows users to view the SSL certificate details.
Common Terms Related to SSL
- TLS (Transport Layer Security): The successor to SSL, offering more advanced security features. TLS is often used interchangeably with SSL, though SSL is technically outdated.
- HTTP (HyperText Transfer Protocol): The standard protocol for transferring data over the web, but without encryption.
- HTTPS (HyperText Transfer Protocol Secure): The secure version of HTTP, using TLS/SSL to encrypt data transmitted between a server and a client.
Why is SSL Important?
1. SEO Ranking Signal
- HTTPS as a Ranking Signal: Google uses HTTPS as a lightweight ranking signal. While it may not be the most critical factor, it can positively affect search rankings. Sites without HTTPS may be penalized in search engine rankings.
2. Security and Privacy
- Encryption: SSL/TLS provides encryption, which secures data transmitted between the server and the client, protecting sensitive information like login credentials and payment details.
- Trust and Credibility: Websites with HTTPS are perceived as more trustworthy by users, enhancing user confidence and potentially improving engagement.
3. Referral Data Preservation
- Referral Information: HTTPS ensures that referral data is preserved, allowing site owners to understand traffic sources accurately.
4. Site Speed Improvements
- Performance: Modern SSL/TLS protocols can improve site speed by leveraging technologies like HTTP/2, which speeds up data transfer.
Best Practices for TLS/SSL Certificates
1. Get Your Certificate from a Reliable Certificate Authority (CA)
- Trusted Providers: Purchase your certificate from well-known CAs like Symantec, GoDaddy, DigiCert, or GeoTrust. Reputable CAs offer technical support and ensure the security of your certificate.
2. Choose the Right Type of Certificate
- Domain Validated (DV): Suitable for blogs or informational sites. Requires minimal verification.
- Organization Validated (OV): Ideal for commercial sites that handle customer information. Provides more extensive validation.
- Extended Validation (EV): Best for sites dealing with sensitive information, such as banking or healthcare. Involves thorough validation of the organization’s identity.
3. Consider Wildcard and SAN Certificates
- Wildcard Certificate: Secures multiple subdomains under a single domain (e.g.,
*.example.com). - SAN (Subject Alternative Name) Certificate: Secures multiple domain names or websites with one certificate.
4. Monitor Certificate Expiry
- Expiration: SSL/TLS certificates are valid for a maximum of 398 days. Renew your certificate within 30 days of expiration to avoid security risks and interruptions.
FAQs
Do SSL/TLS Certificates Cover Sub-Subdomains?
No, wildcard certificates cover only one level of subdomains. For example, *.example.com covers sub.example.com but not sub.sub.example.com. For multiple levels, consider a SAN certificate.
What is the Maximum Lifespan of an SSL/TLS Certificate?
As of September 1, 2020, the maximum validity period for SSL/TLS certificates is 398 days. Certificates must be renewed before expiration.
Can I Get an SSL/TLS Certificate for Free?
Yes, free SSL/TLS certificates are available. Providers like Let’s Encrypt and Cloudflare offer domain-validated (DV) certificates at no cost. Many web hosting providers also include free certificates with their hosting packages.
By implementing SSL/TLS and maintaining best practices, you enhance your website’s security, user trust, and potentially your SEO performance.
