California, U.S.A., November 2019 – 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.

Benjamin Franklin quoted that “Time is money.” The new generation networks are converging on Ethernet to interconnect for data acquisition and control. With everything connected nowadays, 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.

Ethernet Direct offers two types of solutions using Synchronous Ethernet or IEEE 1588 Precision Time Protocol depending on your network infrastructure & requirements.

IEEE 1588 PTP V2 is designed to synchronize distributed and large systems over networks.

IEEE 1588 Precision Time Protocol enables highly precise time synchronization over an Ethernet network over a packet-based network such as Ethernet. This protocol provides a very precise mechanism to correct for delays introduced in the network path from the master clock to the slave clocks. The most important innovation is Ethernet Direct industrial switches support hardware time stamp. Ethernet Direct IEEE PTP V2 switches can provide clock accuracy to primary reference clock in 50 nanoseconds. Time-stamping is achieved within the IEEE-1588 Ethernet physical interface itself. 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. Many power & energy industry focused on PTP to achieve accuracy in electric utility substation automation applications. Precision timing solutions serve to increase an electric utility’s efficiency and uptime by improving monitoring and troubleshooting capability while also reducing capital expenses by converging timing and data networks.

Synchronous Ethernet, also referred as SyncE, is an ITU-T standard for networking devices that facilitates the transference of clock signals over the Ethernet physical layer.

Ethernet Direct SyncE industrial switches provide a synchronization signal to time-sensitive networks. The Synchronous Ethernet signal transmitted over the Ethernet physical layer should be traceable to an external clock, ideally a master and unique clock for the whole network. There are numerous applications which include cellular networks, access technologies such as Ethernet, and applications such as IPTV or VoIP.

Comparison of IEEE 1588 Precision Time Protocol & Synchronous Ethernet

Ethernet Direct SyncE industrial switches provide a synchronization signal to time-sensitive networks. The Synchronous Ethernet signal transmitted over the Ethernet physical layer should be traceable to an external clock, ideally a master and unique clock for the whole network. There are numerous applications which include cellular networks, access technologies such as Ethernet, and applications such as IPTV or VoIP.

Supported Operation

SyncE

• Freerun: Use device itself as a “Grand Master Clock”
• Forced Reference Lock: Use External Clock Source as a “Grand Master
• Forced Holdover: Use device itself as a “Grand Master Clock”, but keep Last
• Automatic: Device automatically select External Clock source while it has multiple clock source

IEEE 1588 PTP

• Master only: Choose External or use itself as a “Grand Master Clock”
• Slave only: Running device as a “Slave Clock”, and get the time from Master
• Ord-Boundary: Running device as a “Boundary-Clock” means one port set as Slave to get the time from Master, all other ports are Master to distribute the time to other connected Slaves.
• P2p Transparent: This clock mode will receive PTP packet from Master and make modification in the packet itself (time relevant parameters) then forward the packet again to Slave or Boundary-Clock.
• E2e Transparent: This clock mode will receive PTP packet from Master and adding time delay parameters in the packet itself then forward the packet again to Slave or Boundary-Clock.

Accuracy

SyncE

• Layer 1 Protocol, its the comparison between Jitter & Wander, much more accurate than PTP
• SyncE is supported by up to 10 Gigabit port and it is unaffected by traffic load.

IEEE 1588 PTP

• 50 nanoseconds (Layer 2 Protocol)

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 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.

To understand how your applications can benefit from Ethernet Direct Sync Ethernet and IEEE 1588 PTP V2 switches, please contact us on by e-mail at sales@ethernetdirect-tw.com