There is zero encryption . Anyone on the network can see the data being transferred. There is also no authentication—if you know the filename, you can usually grab it.
When you plug in an IP phone, it often reaches out to a TFTP server to download its specific configuration settings, wallpaper, and firmware updates. Pros and Cons of TFTP The Advantages: TFTP Server
You might wonder why anyone would use a protocol without passwords or encryption. The answer lies in 1. Booting Diskless Workstations (PXE) There is zero encryption
The transfer ends when a block arrives that is smaller than the standard 512 bytes. TFTP Server