The meaning of any checksum, whether it is at the UDP layer or any other layer is to detect errors in the data. When data is transported over a physical medium, some bits might get flipped creating invalid data. The checksum is a mechanism to detect that and to discard the data if it got corrupted.
[unverified] means Wireshark did not verify the UDP checksum. Which is the default preference in the UDP protocol preferences. This is because a lot of systems do checksum offloading which means the checksum of outgoing packets when captured on a system itself will have bad checksums (as they are not calculated yet).
Assuming there is timeout for retransmitting a block when no ACK is received, you could use a filter like tftp and udp.time_delta > 0.05 to list all TFTP packets that are more than 50ms apart. Use different values depending on the RTT in your network of course...
Asked: 2025-02-25 11:43:00 +0000
Seen: 52 times
Last updated: yesterday
