
, the signal flow and timeslot allocation are as follows:
l
Traffic direction from NE1 to NE2: NE1
→
NE2
Services are added to the source NE (NE1) and are transmitted to the working path and
protection path at the same time. Then, the services are dropped from the sink NE (NE2),
which selects the services from the working path.
l
Traffic direction from NE2 to NE1: NE2
→
NE1
Services are added to the source NE (NE2) and are transmitted on the working path and
protection path at the same time. Then, the services are dropped from the sink NE (NE1),
which selects the services from the working path.
l
The services between NE 1 and NE2 occupy VC-12s 1-5 of VC4-1 (VC4-1:VC-12:1-5) on
the SDH link between NE1 and NE2. The capacity of the services is 5xE1.
When the working path from NE1 to NE2 becomes faulty, in the case of single-ended switching,
the signal flow is as follows:
l
Traffic direction from NE1 to NE2: NE1
→
NE2
Services are added to the source NE (NE1) and are transmitted on the working path and
protection path at the same time. Then, the services are dropped from the sink NE (NE2),
which selects the services from the protection path.
l
The services from NE2 to NE1 are not affected, and the traffic direction is NE2
→
NE1.
Services are added to the source NE (NE2) and are transmitted on the working path and
protection path at the same time. Then, the services are dropped from the sink NE (NE1),
which selects the services from the working path.
When the working path from NE1 to NE2 becomes faulty, in the case of dual-ended switching,
the signal flow is as follows:
l
Traffic direction from NE1 to NE2: NE1
→
NE2
Services are added to the source NE (NE1) and are transmitted on the working path and
protection path at the same time. Then, the services are dropped from the sink NE (NE2),
which selects the services from the protection path.
l
Traffic direction from NE2 to NE1: NE2
→
NE1
Services are added to the source NE (NE2) and are transmitted on the working path and
protection path at the same time. Then, the services are dropped from the sink NE (NE1),
which selects the services from the protection path.
Figure 3-6
Signal flow and timeslot allocation of the 1+1 linear MSP services
VC4-1:1-5(VC12)
VC4-1:1-5(VC12)
NE1
NE2
3-SP3D
1-SL1D-1
1-SL1D-2
Traffic direction of
the working path
Line board
Tributary board
Traffic direction of
the protection path
5xE1 services are
added/dropped
1-SL1D-1
1-SL1D-2
3-SP3D
5xE1 services are
added/dropped
3-SP3D
1-SL1D-1
3-SP3D
1-SL1D-2
1-SL1D-2
1-SL1D-1
Line board Tributary board
Tributary board Line board Line board
Line board
3 Configuring SDH Services
OptiX OSN 550 Multi-Service CPE Optical Transmission
System
Configuration Guide
3-16
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
Issue 02 (2011-06-30)