Hirschmann RS20 User Manual page 149

Synchronizing the system time in the
Stratum Specification
number
0 For temporary, special purposes, in order to assign a better value to one
clock than to all other clocks in the network.
1 Indicates the reference clock with the highest degree of accuracy. A stratum
1 clock can be both a boundary clock and an ordinary clock. Stratum 1 clocks
include GPS clocks and calibrated atomic clocks. A stratum 1 clock should
be synchronized using the PTP from another clock in the PTP system.
2 Indicates the second-choice reference clock.
3 Indicates the reference clock that can be synchronized via an external con-
nection.
4 Indicates the reference clock that cannot be synchronized via an external
connection.
5–254 Reserved.
255 Default setting. Such a clock should never be used as the best master clock.
Table 10: Stratum – classifying the clocks
Cable delays; device delays The communication protocol specified by
IEEE 1588 enables delays to be determined. Formulas for calculating the
current time eliminate 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 lo-
cal time, taking into account the inaccuracy of the local clock in relation to
the reference clock.
Basic Configuration L2P
Release 4.2 07/08
8.3 Precision Time Protocol
149