TDM Clock Configuration
WinLink 1000
D-2
Behavior in fault configuration
D.3
Clock selection
WINLink 1000 automatically selects a single trunk for the timing. The
trunk is selected according to the following rules:
•
Smaller trunk number
•
Both ends line state is in Normal
•
Each line state change in the selected trunk re-triggers a new
clock selection according the above rules.
If the selected trunk is in Los of Signal state, the WINLink 1000 uses its
internal clock.
There are two methods to configure the user equipment.
•
Master / Slave mode – One of the sites is defined as the clock
master while the other site is configured as a time loop (received
clock)
•
Independent (Plesynchronous) Mode – Each site is configured as
timing Master
In both user configurations WINLink 1000 system re-generates the
selected
IN
clock of the opposite site and use it as the
OUT
clock for all
trunks.
In case that there is no
IN
clock in the selected trunk, WINLink 1000
use its internal clock (and re-generate it in the opposite site as an
OUT
clock).
It is user responsibility to verify that all IN clocks of a site are derived
from a single clock source.
D.4
Behavior in fault configuration
Where there are different transmit clocks at the external equipments of
the same site, pattern slips are expected. The pattern slip rate is
proportional to the clock difference. For example if in site A E1 – 1 in
clock is 2.048 Mb/s and E1 – 2 in clock is 2.048 Mb/s + 1 PPM and all
trunks are in normal state, a pattern slip of up to 2000 bits is expected
in trunk 2 every 1000 seconds.
Note
Summary of Contents for WinLink 1000
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