Trivial File Transfer Protocol Server
TFTP is a (trivial) File Transfer Protocol that ensures reliable data transfer over UDP. It does this by using a subset of mechanics that make TCP reliable. The full RFC can be found below, with the packet structure highlighted in this read me.
https://datatracker.ietf.org/doc/html/rfc1350
Packet structure
Initial Read Request
ReadReq acts as the initial read request packet (RRQ) informing the server which file it would like to read
2 bytes string 1 byte string 1 byte
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| Opcode | Filename | 0 | Mode | 0 |
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Data Packet
The data packet contains an opcode, the block number (a monotonically incrementing number used by the server to ensure reliable transfer by waiting for the client to ack the packet by sending the block number back to the server)
2 bytes 2 bytes n bytes
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| Opcode | Block # | Data |
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ACK Packet
Ack responds to the server with a block number to inform the server which packet it just received
2 bytes 2 bytes
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| Opcode | Block # |
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