Five Minute Facts About Packet Timing In multicast PTP a slave port need only subscribe to the PTP multicast addresses and timing will come to it. However, in unicast PTP a slave port has to reach out to the master port it wants time from with PTP message requests. It is more of a client-server […]
What’s new in IEEE 1588-2019: L1 Sync
Five Minute Facts About Packet Timing Time to play what’s new in IEEE 1588-2019, the game where everyone wins new PTP features. L1 Sync is short for physical layer frequency synchronization. Recall that frequency sync is also referred to as syntonization. So, what is it? First, two clocks are syntonized if the they have the […]
What’s in IEEE 1588-2019: DIY PTP Port States
Five Minute Facts About Packet Timing In this installment of What’s in IEEE 1588-2019 we look at the exciting and dangerous world of manual port state configuration1. The Best Master Clock Algorithm leaving you uninspired? No longer a problem, you can configure the state of every PTP Port in your network to be whatever you […]
The PTP AUTHENTICATION TLV
Five Minute Facts About Packet Timing This is the next installment in our series: what is in the 2019 edition of IEEE 1588. Recently, I posted a discussion about GNSS spoofing, and what to do about it. However, the radio interface is not the only way that a hacker could disrupt the timing on your […]
GNSS Spoofing and how to mitigate it
Five Minute Facts About Packet Timing In a previous post I talked about GNSS jamming and how to mitigate it. Today I will discuss GNSS spoofing. Once again GNSS means Global Navisgation Satellite System, which includes not only GPS, but similar systems like the European Galileo. GNSS jamming is bad, but at least you always […]
GNSS jamming and how to mitigate it
Five Minute Facts About Packet Timing This post discusses GNSS jamming, for a discusstion of GNSS Spoofing see the follow up post. Before a timeserver transmits messages with timing information it usually gets that information from a GNSS receiver. That is a Global Navigation Satellite System. Such systems include the Global Positioning System (GPS), Galileo, […]
The Sync Monitor reverse PTP mechanism
Five Minute Facts About Packet Timing By Doug Arnold Since timing is a critical component of many networked systems, there is a desire among network operators to measure the time distribution performance in their networks. This includes logging time compliance for regulations such as MiFID II, as well as well as for general performance monitoring. To […]
TLVs in PTP Messages
Five Minute Facts About Packet Timing By Doug Arnold What is with al of these TLVs in the Precision Time Protocol?Let’s start at the beginning, TLV stands for “type, length, value.” It is a general means to extend a PTP message with some extra information for some optional feature or whatever. TLVs are used in many […]
What’s in the 2019 edition of IEEE 1588: Performance Monitoring
Five Minute Facts About Packet Timing By Doug Arnold Every implementation of PTP includes some information about the state and performance of the device. So in principle a monitoring node could gather all the data and determine the health of the PTP network. Here’s the rub: If you’re the poor soul who is writing the code […]
What’s in the 2019 edition of IEEE 1588: Profile isolation
Five Minute Facts About Packet Timing Next in the series on What is in the 2019 edition of IEEE 1588 is profile isolation. And while we are looking at that we will take a peak at the PTP common message header, the part of PTP message which has the same structure regardless of which PTP […]