Merging Fragments (2)

We know
O(F1) < O(F2) &&
O(F1) + L(F1) < O(F2) + L(F2)
Build new fragment NF
O(NF) = O(F1)
L(NF) = O(F2) + L(F2) - O(F1)
M(NF) = M(F2)
The More Fragments flag
TTL(NF) = min(TTL(F1),TTL(F2))
All other header fields in F1 and F2 the same
Copy values into NF
except the checksum
calculate appropriate value
Copy the data from F1 and F2 into NF
Initial data from F1
Trailing data from F2
Any overlapping data, from either