The DBCACNX consists of two logical sections:
One header always exists and is followed by one or more elements. If data is associated with an element, it may either be included with the element or pointed to by the element. More than one extension may be chained together.
The following figures list the sequential order of the header fields.
When the Level field contains a value of '2', there is an additional header field as shown below:
New development should use only the level 2 form. The level 1 form is deprecated. The following figure lists the sequential order of the elements fields.