• SSLv23 Compatibility mode, used to allow both SSLv3 and TLSv1.
  • SSLv3 Allow only SSLv3.
  • TLSv1 Allow only TLSv1.
  • SSLv2 is disabled. SSLv2 should not be used.


SSL 1.0UnpublishedUnpublished
SSL 2.01995Deprecated in 2011 (RFC 6176)
SSL 3.01996Deprecated in 2015 (RFC 7568)
TLS 1.01999Deprecation planned in 2020
TLS 1.12006Deprecation planned in 2020
TLS 1.22008
TLS 1.32018

In 2014, SSL 3.0 was found to be vulnerable to the POODLE attack.

IP Address Classes (A-B-C-D-E)

ClassAddress rangeSupports
Class A1.0.0.1 to
Supports 16 million hosts on each of 127 networks.
Class B128.1.0.1 to
Supports 65,000 hosts on each of 16,000 networks.
Class C192.0.1.1 to
Supports 254 hosts on each of 2 million networks.
Class D224.0.0.0 to
Reserved for multicast groups.
Class E240.0.0.0 to
Reserved for future use, or research and development purposes.

Setup Load Balancer on DigitalOcean

  1. Create at least 2 nodes (droplets) on the same region. (IP1, IP2).
  2. Create load balancer (IP3).
  3. Create DNS record for IP3 on your domain DNS interface.
  4. Install web server on all nodes for your domain or subdomain.
  5. You can create Let’s Encrypt SSL certificates on all nodes
    for your domain or subdomain, they will work.