A Basic Principle Network Time Synchronization
Duy-Ky Nguyen, PhD
Since early 1980, Network Time Protocol (NTP) and recently Precision Time Portocol (PTP) have been used for network time synchronization.
The similarities are
- both have the same 4 timestamps;
- both assume symmetric transmission paths.
The differences are
- Any PTP slave could become to a master if its clock accuracy is more accurate;
- PTP has timestamp right at the wire, so sending timestamp must be included into the following message.
Basic PTP PDF file is here
TCP/IP Encapsulation and PTP PayLoad PDF file is here
PTP IEEE-1588 Standard PDF file is here
Basic NTP PDF file is here
NTP RFC-1035 PDF file is here
History of NTP PDF file is here
