Is the file in a location that you can map a drive?
If so, you could try the Read File step.
In this step, configure the file name/location and save the input into a property:
Use another step to do something with the file.
Notes:
- The file path must be accessible from the machine (local or DT server) that is executing the step.
- The file path can be parameterized using {{ }} notation if desired.
- File size may or may not be an issue. For example, if you are moving '000s of MB, I cannot say what the performance would be.
- There is also a DT FTP step available. I am unfamiliar with Tectia FTP, but I assume you have a technique for passing the file (property) to the FTP client.
There is a custom SSH/FTP step that you can search for in Communities. I do not know the status of this code.
Let us know if this helps.