SSL certificates (Secure Sockets Layer) are digital certificates that provide encryption and authentication for websites.

What is SSL?

SSL is a security protocol that encrypts communication between a web browser and a web server, protecting transmitted data.

Certificate Types

By Validation

  • DV (Domain Validated): Domain validation
  • OV (Organization Validated): Organization validation
  • EV (Extended Validated): Extended validation

By Coverage

  • Single Domain: Single domain
  • Wildcard: Subdomains of a domain
  • Multi-Domain: Multiple domains
  • Unified Communications: Unified communications

Obtainment Process

Request

  • CSR: Generate Certificate Signing Request
  • Information: Provide organization information
  • Validation: Validation process
  • Issuance: Certificate issuance

Installation

  • Server: Install on web server
  • Configuration: Configure server
  • Testing: Test functionality
  • Monitoring: Monitor certificate

Configuration

Apache

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# SSL configuration in Apache
<VirtualHost *:443>
    ServerName example.com
    DocumentRoot /var/www/html
    
    SSLEngine on
    SSLCertificateFile /path/to/certificate.crt
    SSLCertificateKeyFile /path/to/private.key
    SSLCertificateChainFile /path/to/chain.crt
</VirtualHost>

Nginx

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# SSL configuration in Nginx
server {
    listen 443 ssl;
    server_name example.com;
    
    ssl_certificate /path/to/certificate.crt;
    ssl_certificate_key /path/to/private.key;
    ssl_trusted_certificate /path/to/chain.crt;
    
    location / {
        root /var/www/html;
        index index.html;
    }
}

Renewal

Automatic

  • Certbot: Let’s Encrypt tool
  • Scripts: Renewal scripts
  • Cron: Scheduled tasks
  • Monitoring: Expiration monitoring

Manual

  • Process: Renewal process
  • Validation: Revalidation
  • Installation: Reinstallation
  • Testing: Functionality testing

Best Practices

Configuration

  • Strong encryption: Use strong encryption
  • Protocols: Use secure protocols
  • Headers: Configure security headers
  • HSTS: Implement HSTS

Monitoring

  • Expiration: Monitor expiration
  • Renewal: Automatically renew
  • Validation: Validate functionality
  • Alerts: Configure alerts

Security

  • Keys: Protect private keys
  • Rotation: Rotate certificates
  • Revocation: Revoke compromised certificates
  • Audit: Regular audits

References