Transport Layer Security (TLS) is a protocol that provides security between clients and server. Due to 4D v20 now upgrading to TLS 1.3, note the differences below:

v19
- Default TLS version is TLSv1_2
- Possible values for SET DATABASE PARAMETER for Min TLS version are:
   - TLSv1_0
   - TLSv1_1
   - TLSv1_2
   - TLSv1_3

v20
- Default TLS version is TLSv1_3
- Possible values for SET DATABASE PARAMETER for Min TLS version are:
   - TLSv1_2
   - TLSv1_3

Note that v20 has deprecated TLSv1_0 and TLSv1_1 so be sure to keep this in mind as connection attempts from clients or other apps running on deprecated TLS versions may be rejected.