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EKOSync 1588 User Manual rev 3.10
Grandmaster Clock
The root timing reference is called the grandmaster. The grandmaster transmits
synchronization information to the clocks residing on its network segment. A grandmaster clock
is the highest-ranking clock within its PTP subdomain and is the primary reference source for all
other PTP elements. In a PTP network a grandmaster is the node that defines the correct time.
Ordinary Clock
An ordinary clock is a PTP clock with a single PTP port. It could be a master clock (grandmaster)
or a slave clock. Ordinary clocks are the most common device within a PTP network.
Boundary Clock
A boundary clock is a device between PTP grandmaster and PTP slave clients. A boundary clock
has multiple network connections and can act as a source (master) and a destination (slave or
client) for synchronization messages. The boundary clock intercepts and processes all PTP
messages and passes all other traffic.
Transparent Clocks
Transparent clocks measure and adjust for packet delay. The transparent clock computes the
variable delay as the PTP packets pass through the switch. There are two types of transparent
clocks, end-to-end and peer-to-peer. End-to-end transparent clocks update the time interval
field for the delay associated. However peer-to-peer transparent clocks measure the line delay
associated. Transparent clocks improve synchronization between the master and slave clocks
and ensure that the master and slave clocks are not impacted by the effects of packet delay
variation.
