This can be done by concatenating timestamped digital signatures onto messages. The timestamp protocol is an alternative to nick/channel delays which resolves collisions using timestamped priority. It records the selected sessions into encrypted, timestamped, and digitally signed audit trails. A Timeline of dendrochronology timestamped events. The server receives timestamped notifications of changes made to the document by other users. PTPd accuracy depends on how IEEE 1588 packets are timestamped on the participating machines. Thus, eight timestamped events are generated per axle. Each cell of a bigtable can have zero or more timestamped versions of the data. Both of these approaches allow recordings to be timestamped, often required for legal reasons.