It provides printer spooling and network print server functionality using the Line Printer Daemon protocol. Spooling is a combination of buffering and queueing. DNOS supports output spooling and program accessible accounting data. Third, spooling two cables down and then connecting the ends, forming a loop. With the parallel groove system, rope wear is considerably reduced in multilayer spooling. Film is commonly checked for broken sprocket holes before presentation, a process known as "spooling". The PRINT command did this to implement background print spooling. The FH880 drum memory unit was also supported as a spooling and file-storage media. Many installations used Houston Automatic Spooling Priority (HASP) to mitigate the complexity. Several seconds later, the CVR recorded the sound of the engines spooling up. A balance stripe was added on the opposite edge to facilitate spooling of the film. George 2 added the concept of spooling.