4.21.1.1. Protocol elements

TFTP supports five types of packets, all of which have been mentioned above:

  • 1 - Read request (RRQ)

  • 2 - Write request (WRQ)

  • 3 - Data (DATA)

  • 4 - Acknowledgment (ACK)

  • 5 - Error (ERROR), which can contain the following error messages:

    • 0 - Not defined, see error message (if any).

    • 1 - File not found.

    • 2 - Access violation.

    • 3 - Disk full or allocation exceeded.

    • 4 - Illegal TFTP operation.

    • 5 - Unknown transfer ID.

    • 6 - File already exists.

    • 7 - No such user.