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LTI allows a platform to include Resource Links on its pages. These links (like literally HTML hyperlinks) are responsible for “Launching” a tool. There are rules on how to structure a link and what information it needs to include. There are rules on how to perform a launch. Long story short, you need to specific specify who you are, who the tool is, who the user is, and where the link appears on the page, all with unique identifiers. LTI also provides facilities/protocols for performing authentication during this process.
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