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From the results, we chose a free simple SSL certificate from the CA StartCom in a SSL certificate package called StartSSL Free.
Note there is a newer service (checked July 2018), a non-profit called Let's Encrypt that provides free SSL certificates. To understand what you get, you may look at their Hello World site.
SSL Setup (using openssl)
Server keys must be generated for the Certificate Signing Request (CSR). Openssl will be used to generate this CSR.
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