California, U.S.A., February 2018 – Ethernet Direct Corporation, a professional and primary provider of industrial networking and communication solutions is pleased to share how to achieve nanoseconds clock accuracy in time sensitive networking applications.

Mission critical systems such as in Telecommunications, Defense, Military, Intelligence, Reconnaissance (C4ISR), Command and Control, Rail transport, Power stations and other businesses often include several counters and clocks to keep track of precise time synchronization across multiple devices. Synchronized clocks in shared network in distributed systems would require critical real-time connectivity.

Typical devices use the Network Time Protocol (NTP) to set their clocks by obtaining the time of day from a remote server. To synchronize with an NTP server, a client sends a request and then waits for a reply which could lead to a few milliseconds. Maintaining accurate time is critical for high-end applications and the evolution of IEEE 1588 PTP V2 and Synchronous Ethernet resolve timing issues as simple as connecting “Sync Ethernet Sync Direct” switches to the network. Attention focuses on a reliable managed Ethernet switch to handle a high level of user control and security with features such as time synchronization, traffic monitoring, advanced security, priority/sensitivity handling, failover mechanisms, and built-in test.

Ethernet Direct industrial managed switches support IEEE 1588-2008, also known as PTP V2 which addresses the limitations of NTP and GPS for synchronization of systems on a local network. Ethernet Direct IEEE PTP V2 switches can provide clock accuracy to primary reference clock in 50 nanoseconds. Our switches can be configurable to act as grand master clock source as supports IEEE PTP V2 for precise synchronization to operate in Ordinary-Boundary, Peer to Peer Transparent Clock, End to End Transparent Clock, Master, Slave port by each port. The application of PTP is typically deployed on local networks and designed for local systems requiring accuracies beyond those attainable using NTP or for applications that cannot bear the cost of a GPS receiver at each node, or for which GPS signals are inaccessible. The PTP V2 concept of a “transparent clock” notes the time that it receives a PTP packet on an ingress interface, and notes it again when the packet is transmitted on an egress interface. The switch can then inform the PTP message recipient of the delay introduced by the switch. In this way, network delay can be fully eliminated as a source of synchronization error. Reference to Wikipedia description of the IEEE 1588 architecture, this standard describe a hierarchical master-slave for clock wherein characterized by a time distribution system consists of one or more network segments and one or more clocks. An ordinary clock is a device with a single network connection and is either the source of (master) or destination for (slave) synchronization reference. A boundary clock has multiple network connections and can accurately synchronize one network segment to the other. A synchronization master is selected for each of the network segments in the system. The root timing reference is called the grandmaster. The grandmaster transmits synchronization information to the clocks residing on its network segment. The boundary clocks with a presence on that segment then relay accurate time to the other segments to which they are also connected. A simplified PTP system frequently consists of ordinary clocks connected to a single network, and no boundary clocks are used. A grandmaster is elected and all other clocks synchronize directly to it.

The IEEE 1588-2008 introduces a clock associated with network equipment used to convey PTP messages. The transparent clock modifies PTP messages as they pass through the device. Timestamps in the messages are corrected for time spent traversing the network equipment. This scheme improves distribution accuracy by compensating for delivery variability across the network.

To understand how your applications can benefit from Ethernet Direct Sync Ethernet and IEEE 1588 PTP V2 switches, please contact us on by phone 1-888-895-8256 (U.S. toll free) or e-mail sales@ethernetdirect-us.com or sales@ethernetdirect-tw.com

Product information is also available at www.ethernetdirect-tw.com