3. "Length" field

We could change the significance of the "Length" field. Increasing the value of this field has also increased the size of the package, so we can change the fields of data octets by appending to the end of datagram.

So processing is possible when the package was a source of hidden data. So if the modification had occurred at the source device, the receiving host cannot properly assemble the original packets. This manipulation cannot be detected by the packet sniffer.

**Figure 4.** *Header of UDP.*
