After TTL changes, the IPv4 header checksum is recomputed with the checksum word zeroed.
Checksum covers the header
The IP version 4 header checksum covers the header. When TTL changes, the checksum must be recomputed.
checksum word index=5
Zero the checksum word
For compute mode, word index 5 is treated as zero before summing.
zeroed word=5
Computed after checksum
The recomputed after checksum is 0xb2e6.
after checksum=0xb2e6
Summary
TTL changed one byte, so the header checksum was zeroed and recomputed.
after checksum=0xb2e6