Migrating from LTI 1.0/1.1 to 1.3
For the first time in LTI’s history we need to handle migrating from one version to another. Before 1.3 the changes were all additive, but with 1.3 the payload format and security model have changed significantly, so we need a way to migrate existing LTI 1.1 (and 1.0) links to support the 1.3 format.
Note that Learn has never allowed two tools or applications to be configured in the same Learn instance with the same fully qualified domain name (fqdn). This means that you cannot have both a 1.1 version and a 1.3 version of a tool configured at the same time if they use the same fqdn.
If a tool provider wants to upgrade their tool to LTI 1.3/Advantage but not break all of an institution’s existing links then they will need to host their LTI 1.3/Advantage tool at the same fqdn.
In Learn we automatically upgrade the links for a tool when a Learn administrator deploys the 1.3 version of the tool.
At deployment time, if Learn sees there is an existing 1.1 tool registered with the same domain(s) as the 1.3 tool the admin is prompted to migrate the links. If they choose “yes” then we migrate ALL LTI 1.1 links to the new LTI 1.3 application, effectively removing the LTI 1.1 domain configuration. The links remain and should work fine if the tool developer has done their job correctly. The target_link_uri for the 1.3 tool is the same as the launch URL defined in the LTI 1.1 placement or link.