After the content section of responses a summary section follows for inventories and searches to give information about the paging status:

<verbatim>
  ...
  </inventory>
  <summary start="5" totalReturned="5" next="10" ResponseSummary>
</response>
</verbatim>

The next attribute specifies the index of the next record which was not returned because of the paging.
If there is no more record, the next attribute is not existing.