The administrator needs to install SSL to make the website trusted. SSL stands for Secure Sockets Layer, which is an encryption-based Internet security protocol that ensures privacy, authentication, and data integrity in web communications. SSL enables HTTPS (Hypertext Transfer Protocol Secure), which is a secure version of HTTP (Hypertext Transfer Protocol) that encrypts the data exchanged between a web browser and a web server. SSL also uses digital certificates to verify the identity of the web server and establish trust with the web browser. A web server that implements SSL has HTTPS in its URL instead of HTTP and displays a padlock icon or a green bar in the browser's address bar.

A checksum is a value that is calculated from a data set to verify its integrity and authenticity. A checksum can be used to compare a downloaded installation package with the original source to ensure that the package has not been corrupted or tampered with during the download or transmission process. If the checksums match, then the package is safe to install. If the checksums do not match, then the package may be infected with malware or contain errors that could cause installation problems. Therefore, validating the checksum for the downloaded installation package is a necessary step before launching the installation again12
1: CompTIA Server+ Certification Exam Objectives 2: How to Verify File Integrity Using Checksums on Linux