The lwp::protocol::https module provides support for using https schemed urls with lwp. lwp::protocol::https is a plug-in to the lwp protocol handling, so you don't use it directly. once the module is installed lwp is able to access sites using http over ssl/tls.

if hostname verification is requested by lwp::useragent's ssl_opts, and neither ssl_ca_file nor ssl_ca_path is set, then ssl_ca_file is implied to be the one provided by ca-certificates.

this module used to be bundled with libwww-perl, but it was unbundled in v6.02 in order to be able to declare its dependencies properly for the cpan tool-chain. applications that need https support can just declare their dependency on lwp::protocol::https and will no longer need to know what underlying modules to install.