Modes Of Operation - Ericsson Marconi OMS 1200 Product Description

The protection logic of each end determines the highest priority request that is active.
This may be a remote request (received via the K1 byte) or a local request (condition,
state or switch request of the local MSP function). The protection logic sets the bridge
in accordance with the highest priority request. The resultant bridge position is
indicated in K2 bits 1-4. For the generation of the sent K1 byte, only the highest
priority request is considered.
7.4.3.2 Siemens Accelerated K1/K2 MSP Protocol
The SMA also supports the Siemens Accelerated Protection Switching protocol for
1+1 bi-directional switching for a network using predominantly 1+1 bi-directional
switching. The K1, K2 bytes are still used for signalling, however, only a single K1, K2
protocol exchange is required to complete a bi-directional switch. This protocol may
only be used for bi-directional switching.
When the protection section is not in use, Null Channel is indicated for the sent K1
bytes on both ends. Bits 1-4 of K2 bytes sent at both ends of the section are set to
0001 to indicate that the selector is released and receiving traffic from the working
section.
The protection logic of each end determines the highest priority request that is active.
This may be a remote request (received via the K1 byte) or a local request (condition,
state or switch request of the local MSP function). The protection logic sets the
selector in accordance with the highest priority request. The resultant selector position
is indicated in K2 bits 1-4. For the generation of the sent K1 byte, only the highest
priority request is considered. Remote requests are not considered, and Reverse
Request is never indicated.
7.4.4

Modes of Operation

The MSP architecture is outlined in Table 7-12 (1+1 link protection). Control of the
(effective) two-way switches at the receive ends of the links is performed according to
the selected mode of operation. There are four modes of operation, which are
configurable options at the LCT/LCTS (although the SMA might adopt a different
mode according to other factors as described later in this chapter). These modes are:
•
•
•
•
Note:
Note:
221 02-ZAP 701 25/1 Rev C 2006-08-04
03PHB00004AAV-CUA
Revertive
Non-revertive
Uni-directional
Bi-directional.
The default mode of operation is Bi-directional Non-revertive.
It is not possible to use the Siemens Protocol in Uni-directional mode of
operation.
Marconi OMS 1200
Technical Product Description
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