Network Time Protocols working group Accurate, precise, and reliable time is a key component of all modern systems, devices, and applications. This requires reliable and accurate network time synchronization over modern IP-based networks. Additionally, accurate time is fundamental to implementing many important security properties, and therefore often must be (cryptographically, or otherwise) secured. The Network Time Protocols working group is focused on enhancing existing network time synchronization protocols, such as the Network Time Protocol (NTP), and specifying new network-time-related protocols or extensions for purposes that the existing protocols are not well suited to address. NTP was first defined in the IETF in RFC 958 in 1985. It has been through several iterations in the IETF. The latest, NTPv4 (RFC 5905) was published in 2010. Today, it is a widely used time synchronization protocol for the synchronization of clocks of various digital systems including computers, networks, and a myriad of devices. Despite NTP's wide-spread success, it has become apparent that it needs further development in order to adequately meet the modern requirements of time synchronization protocols and to meet the increasing security threats on the Internet. The working group will continue to address the maintenance of NTPv4, including extensions and corrections. This includes the introduction of an interleave mode in order to enhance the accuracy of the network time synchronization and the introduction of alternative clock selection algorithms in order to enhance robustness against delay attacks. NTP remains vulnerable to many types of attacks. Therefore, in 2020, the working group published Network Time Security (NTS) as RFC 8915. NTS extends NTP with an authentication approach to ensure authenticity of NTP time servers and protects the integrity of exchanged NTP packets. The working group will work on extending NTS to cover the remaining modes of service for NTP not covered by the initial specification. The working group will also work on extending NTS for PTP [1] in collaboration with the IEEE 1588 working group. The working group will also develop an updated version of NTP (preliminarily known as NTPv5), addressing a number of identified weaknesses. The new specification will consist of a set of documents, separating the on-wire protocol engine and the timing engine of NTP clients and servers. The updated version of NTP will address the security requirements specified in RFC 7384 and leverage the work completed in RFC 8915. Finally, the working group will address other network-time-related protocols in the IETF (e.g., roughtime) as well as work on items brought to the group from other standards bodies (e.g. IEEE 1588), with the acknowledged request to do so from that body. Working group items: * YANG model for NTPv4 * interleaved mode for NTPv4 * alternative clock selection algorithms * NTS for PTP * NTPv5 requirements * NTPv5 specification(s) * roughtime specification [1] "IEEE Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems," in IEEE Std 1588-2019 (Revision of IEEE Std 1588-2008) , pp.1-499, 16 June 2020, doi: 10.1109/IEEESTD.2020.9120376.