22.214.171.124.4.1 Structure with Trailing Gap
NDR64 represents a structure as an ordered sequence of representations of the structure members. The trailing gap from the last nonconformant and nonvarying field to the alignment of the structure MUST be represented as a trailing pad. The size of the structure MUST be a multiple of its alignment. See the following figure.
Figure 11: Structure with trailing gap
For more information, see the example in section 4.8.