Web sites not supporting HTTPS are going nowhere nowadays. Luckily, there are some certificate authorities providing certificates with short-term expiration. For example:
WUSON Practice Field as a Software Test Engine
I’ve used free certificates from Let’s Encrypt to implement LINE bots and turned to ZeroSSL this time for my new project, WUSON Practice Field for Wentz QOTD, hosted on a new website, https://QOTD.WentzWu.com.
The ZeroSSL user interface is quite handy and efficient. You can typically apply for a certificate in five minutes. It provides a certificate package containing three files:
Install the Certificate on an IIS Server
For Microsoft IIS administrators to install a certification on the IIS server, they need a .pfx file, a package that contains both the private key and certificate. The following OpenSSL command can do so:
openssl pkcs12 -export -out qotd.wentzwu.com.pfx -inkey private.key -in certificate.crt
Certificate Subject and the DNS Name
The domain name shall map to the one registered in the certificate, so you have to configure your DNS resource record and use it as the subject name when applying for the certificate.
In the process of implementing HTTPS support, I found the following links helpful: