IEEE 1588v2 (also known as Precision Time Protocol, PTP) is an industry-standard protocol that enables the precise transfer of frequency and time to synchronize clocks over packet-based Ethernet networks between a system Grandmaster clock and slave clock within same clock domain. Please click the below link for more info regarding the PTP overview from Juniper. https://www.juniper.net/techpubs/en_US/junos/topics/concept/ptp-overview.html
The need for providing time accuracy and synchronization in the enterprise, data center, and financial networks is growing. Also, the Market in Financial Instruments Directive (MiFID II) enforced by the European Securities and Market Authority (ESMA) will require all trades to be time-stamped to UTC at a high-level of precision, effective in January 2018.
So, the IETF has developed new PTP profile for Enterprise IT Networks. Please find the below link for more detailed info from the latest draft, which is version 06.