Marconi OMS 1200
Technical Product Description
221 02-ZAP 701 25/1 Rev C 2006-08-04
© Ericsson AB 2006
03PHB00004AAV-CUA
Commercial in confidence
109
(136)
Figure 7-10: STM-4/16 Core Card Equipping Options
STM 4/16 CORE CARD
'A'
LINE
EAST
LINE
WEST
STM 4/16 CORE CARD
'B'
y
Duplicated Core Card
y
Linear MSP (Terminal)
y
SNCP (ADM)
y
MS-SPRING
For an in-traffic, unprotected system, core card protection is commissioned by the
logical addition of a second core card (Traffic Core B).
Note:
Core card protection always operates in non-revertive mode; logically adding
a second core card to an in-traffic system does not instigate protection
switching by peripheral traffic cards and functions (i.e, traffic affecting
switching is avoided unless contra-indicating failures are detected).
On power-up, a system in which two switch units are fitted defaults to protected
operation and the card-in-traffic indicator is lit on cards of both core units. This
indicates that removal of a card of either core unit may disrupt traffic.
Note:
Although one core is not carrying traffic, the In-traffic LED is lit.This indicates
that both core cards are available to pass traffic and it is unsafe to remove
either core card.
7.7.2.1 Reconfiguration
for Protected Operation
To add core unit protection to a currently unprotected traffic-carrying system, a second
core unit is fitted to the equipment shelf. Once the unit has been logically added to the
shelf, the card-in-traffic indicator of the added core unit is lit and the protection
mechanism activated. The traffic from the original switch unit remains selected by the
destination ports (preventing any unnecessary, traffic-degrading switchovers).
7.7.2.2
Removal of a Core Unit from a Traffic Carrying SMA
During operation, it may become necessary to remove one of the cards from a system
that is carrying traffic.
Note:
Removing Traffic Core A also removes the NE’s CCU function, therefore
forced switches must be put in place before removing cards.
Three possible situations arise:
1
Removal of a failed core card.