Hirschmann RS20 User Manual page 108

Synchronizing the System Time in the
Network
PTPv1 PTPv2
Stratum Clock class
number
3 187
4 248
5–254 –
255 255
Table 6: Stratum – classifying the clocks
 Cable delays; device delays
The communication protocol specified by IEEE 1588 enables delays to be
determined. Algorithms for calculating the current time cancel out these
delays.

Accuracy of local clocks
The communication protocol specified by IEEE 1588 takes into account
the inaccuracy of local clocks in relation to the reference clock.
Calculation formulas permit the synchronization of the local time, taking
into account the inaccuracy of the local clock in relation to the reference
clock.
108
Specification
Indicates the reference clock that can be synchronized via an
external connection.
Indicates the reference clock that cannot be synchronized via an
external connection. This is the standard setting for boundary
clocks.
Reserved.
Such a clock should never be used as the so-called best master
clock.
7.3 Precision Time Protocol
UM BasicConfig L2E
Release 8.0 05/2013