All networked computer systems require some form of temporal synchronization. As networks have gotten faster the demands for accurate, distributed, timekeeping have increased, but most programmers have no idea about the quality of the clocks in their systems, nor how they might be kept in sync. Most programmers have at least heard of NTP (The Network Time Protocol) which is used to synchronize computer clocks over a network, but fewer have heard about more recent work, such as the Precision Time Protocol which can keep computers accurate to within several hundred nanoseconds when working over a LAN. Well synchronized clocks are used in financial applications such as High Frequency Trading as well as the electrical grid and cellular telephone networks.

This talk will cover:

• How computers keep track of the time, and how they fail miserably at this.
• The fundamental ideas behind network based time keeping, why we do it, and how it works.
• Network Time Protocols (NTP and PTP) deployment, use and tuning.