Five Minute Facts About Packet Timing By Doug Arnold Next in the series on What is in the 2019 edition of IEEE 1588 is slave port monitoring, also known as slave event monitoring. Sometimes it is not enough to transfer time accurately from a PTP Grandmaster (GM) to a PTP Slave (slave). Sometimes you also […]
PTP Timescale (and what the heck is Arb time?)
Five Minute Facts About Packet Timing By Doug Arnold Most application which use PTP to distribute time, don’t actually need standard time, as understood by national laboratories. All that is needed is for the clocks in a network to have the same time. However, there are several reasons to use a standard timescale when distributing […]
What’s in the IEEE 1588 revision: Interdomain interactions
Five Minute Facts About Packet Timing By Doug Arnold The next installment in what’s in the revision of IEEE 1588 discusses PTP domains Before we get started. A quick review on domains. Every PTP message contains a domain number. A PTP instance is configured to work in one, and only one, domain. It is required […]
What’s in the 2019 edition of IEEE 1588: Mixed Multicast Unicast Operation
Five Minute Facts About Packet Timing By Doug Arnold The next installment in what’s in the revision of IEEE 1588 discusses mixed multicast-unicast operation. In a previous post I described the virtues of mixed multicast-unicast operation in PTP. Sometimes this is referred to as the “hybrid mode”. I summarize the conclusion here, but if you […]
HSR and PRP: redundant Layer 2 networks
Five Minute Facts About Packet Timing By Doug Arnold If are looking into network technologies for power substations, or industrial automation you may run across HSR and/or PRP. So here is the five-minute version of what these things are. First of all, both HSR and PRP are layer s network protocols, which have include the […]
The virtues of clock watching: Why it’s important to monitor your timing network
Five Minute Facts About Packet Timing By Doug Arnold A network architect’s job is never done. It is not enough to design the network, and see that design implemented. You need to keep checking to make sure that everything still works as the network evolves. It’s certainly true for your network-based timing system. First remember […]
What’s coming in the 2019 Edition of IEEE 1588: Special Ports
Five Minute Facts About Packet Timing By Doug Arnold Our next update on what’s in the 2019 edition of IEEE 1588 , delves into the mysterious sounding topic of special ports. A special port happens when a PTP network interfaces with a transport media which has a built in timing mechanism. Two examples are Wi-Fi and Ethernet […]
What’s coming in the 2019 Edition of IEEE 1588: Modular Transparent Clocks
Five Minute Facts About Packet Timing By Doug Arnold As I promised earlier, I will be updating you on what’s in the 2019 edition of IEEE 1588. One of the treasures that you will find is the ability to build modular Transparent Clocks (aka, modular TCs). That is TCs which can be built by installing […]
What’s In the 2019 Edition of IEEE 1588?
Five Minute Facts About Packet Timing By Doug Arnold The new edition of IEEE 1588, IEEE 1588-2019 is finally available. The name is based on the year it approved by the IEEE Standards Board, not the year it is published. So, what’s there? Everything that was added or changed was for the purpose of: Making […]
The Art of Negotiation, the PTP Way
Five Minute Facts About Packet Timing By Doug Arnold and Andreja Jarc A previous post discussed unicast PTP. Most PTP Profiles are based on multicast communication. However, PTP can operate using unicast. This is necessary in networks which don’t support multicast, or if there is a large number of PTP slaves, which would generate too […]