HUAWEI OptiX OSN 8800 T64/T32 Intelligent Optical Transport Platform. Product Description - part 32
7.6.13 Service Association
Service association can be used to associate the same services accessed from different points
into an ASON network.
Service association involves associating two ASON services that have different routes. During
rerouting or optimization of either service, the rerouting service avoids the route of its associated
service. Service association is mainly used for services (dual-source) accessed from two points.
As shown in Figure 7-49, D-E-I and A-B-G-H are two associated LSPs. When the fiber between
B and G is cut, rerouting of A-B-G-H LSP avoids D-E-I LSP.
Figure 7-49 Service association
R4
R1
E
1+1protection
I
1+1protection
D
F
C
A
B
H
G
R2
R3
: ASON NE
: User equipment
Table 7-25 lists the attributes of service association.
Table 7-25 Attributes of service association
Attribute
Service Association
Service creation
Supports the creation of the associated services with the same source
node.
Service
Supports optimization of associated services.
optimization
Rerouting
When one service reroutes, it avoids the route of the associated service.
Service type
l Supports the association of two silver services.
l Supports association of two copper services.
l Supports the association of a silver service and a copper service.
l Supports the association of two silver tunnels.
l Supports the association of two copper tunnels.
l Supports the association of a silver tunnel and a copper tunnel.
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7.6.14 Service Optimization
After the topology changes several times, the ASON may have less satisfactory routes and thus
requires service optimization. Service optimization involves creating a new LSP, switching the
optimized service to the new LSP, and deleting the original LSP to change and optimize the
service without disrupting the service. Of course, the service route can be restricted during the
service optimization.
LSP optimization has the following features.
l Only manual optimization is supported.
l The optimization does not change the protection level of the optimized service.
l During optimization, rerouting, downgrade/upgrade, or deleting operations are not allowed.
l During creation, rerouting, downgrading/upgrading, starting or deleting operations,
optimization is not allowed.
l The following service types support optimization: diamond, gold, silver, copper, iron and
tunnel services.
7.6.15 Service Migration
OptiX ASON software supports the conversion between ASON services, and between ASON
services and traditional services. The service conversion is in-service conversion, which would
not interrupt the services.
Service Migration between ASON Trails and Permanent Connections
Currently, Huawei ASON software supports the following migration between the traditional
SDH services and ASON services:
l Migration between diamond services and permanent SNCP connections
l Migration between gold services and permanent connections
l Migration between silver services and permanent connections
l Migration between copper services and permanent connections
l Migration between iron services and permanent connections
l Migration between tunnel services and server trail.
Service Migration between ASON Trails
The ASON software supports the following migration between the traditional SDH services and
ASON services:
l Migration between diamond, gold, silver, and copper services
l Migration between diamond, gold, silver, and copper tunnels
7.6.16 Preset Restoration Trail
Customers may require that the services route to a specified trail in the case of trail failure. To
this end, the ASON software provides the function of presetting the trail for restoration. This
function helps increase the controllability of service routing. The preset restoration trail
information is stored only on the control plane and requires no physical resource.
The ASON software supports setting a preset restoration trail for a diamond/silver/gold ASON
trail. When the ASON trail reroutes, the service is restored to the preset restoration trail first.
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In the case of a service configured with a preset restoration trail, when this preset restoration
trail fails, the system recalculates a new preset restoration trail during regular detection (by
default, the interval is 60 minutes) and reports a preset restoration trail update event to the NMS.
7.6.17 Trail Pre-Computation and Adjustment
When optimizing the routes of new ASON services or original services, users can issue the route
pre-computation command through the U2000. In this manner, users can acknowledge the
service routes to be created, routes after optimization, specific routes involving service
restoration trails in advance. In addition, users can properly adjust the pre-computed trail
according to service trail requirements.
7.6.18 Reverting Services to Original Routes
After many changes in an ASON network, service routes may differ from the original routes.
You can revert all service to the original routes.
Generally, the route during ASON service creation is the original route of the ASON service. If
the original route recovers after rerouting of the ASON services, the services can be adjusted to
the original route manually.
7.6.19 Amalgamation of ASON and LCAS
In OCS networking, the ASON supports amalgamation of ASON and LCAS.
LCAS
LCAS is Link Capacity Adjustment Scheme. With LCAS enabled, the bandwidth of VCTRUNK
can be adjusted dynamically without affecting services. As shown in Figure 7-50, VCTRUNK1
is bound with four VC4s, with two transmitted over path 1 and two over path 2. If the VC-4 in
path 1 fails, the two VC4s in path 2 will transmit all Ethernet service without affecting the service
of VCTRUNK1. You can add VC-4 on either path if necessary.
Figure 7-50 LCAS (different path)
Path 1
VCTRUNK1
Router A
Router B
NE1
NE2
Path 2
If these VC4s are transmitted over a path, adding/deleting VC-4 will not affect the service. As
shown in Figure 7-51, VCTRUNK1 is bound with four VC4s. If the first VC-4 fails, the Ethernet
service remains unaffected.
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Figure 7-51 LCAS (same path)
VCTRUNK1
Router A
Router B
NE1
NE2
ASON Trail Group
An ASON trail group associates all member trails for the same LCAS service within one LSP
group. These member trails then can be added, deleted or modified. To provide virtual services
with the error tolerance ability, these member trails must be as separate as possible.
Each ASON trail group is identified by an ID. The ASON NE allocates an ID to each ASON
trail group. The member trails within an ASON trail share the same source and sink. The trails
must also be as separated as possible.
7.6.20 Merging an ASON Network with a Traditional SDH
Network
An ASON network can be used with an SDH network to form a hybrid network. In this case, an
end-to-end service can be managed and created in a centralized manner.
A Traditional SDH Network Connected to an ASON Network in 1+1 or 1:1 MSP
Mode
A traditional SDH network is connected to an ASON network in 1+1 or 1:1 MSP mode. The
connection between the SDH network and the ASON network is protected in linear MSP mode.
The ASON network adopts the intelligent protection or restoration mode. In addition, the ASON
network can access a diamond service, a gold service, or a silver service, as shown in Figure
7-52.
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Figure 7-52 A traditional SDH network connected to an ASON network in 1+1 or 1:1 MSP
mode
1+1 or 1:1 MSP
MSP Ring
ASON
: ASON NE
: SDH NE
A Traditional SDH Network Connected to an ASON Network in SNCP Mode
A traditional SDH network is connected to an ASON network in SNCP mode. In this case, a
service can be protected in SNCP mode. The SDH network adopts the traditional SNCP mode.
The ASON network adopts the intelligent protection or restoration mode. As shown in Figure
7-53, the service can also be protected if two fiber cuts occur.
Figure 7-53 A traditional SDH network connected to an ASON network in SNCP mode
SNCP Access
SNCP Access
Dual-fed
selective
receiving
SNCP
SDH
ASON
SDH
Dual-fed
selective
receiving
SNCP
: ASON NE
: SDH NE
VC-4 Services Between SDH NEs That Cross the ASON Network
As shown in Figure 7-54, a VC-4 service is created between SDH NEs 5 and 6 and crosses the
ASON network. The ASON network adopts the intelligent protection or restoration mode. The
SDH network is not protected.
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Figure 7-54 VC-4 services between SDH NEs that cross the ASON network
NE1
NE4
NE6
NE5
VC-4
VC-4
NE2
NE3
: ASON NE
: SDH NE
VC-12 Services Between SDH NEs That Cross the ASON Network
As shown in Figure 7-55, a VC-12 service is created between SDH NEs 5 and 6 and crosses the
ASON network. The ASON network adopts the intelligent protection or restoration mode. The
SDH network is not protected.
Figure 7-55 VC-12 services between SDH NEs that cross the ASON network
NE1
NE4
NE6
NE5
VC-12
VC-12
NE2
NE3
: ASON NE
: SDH NE
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1+1 VC-4 Services Between Traditional NEs That Cross the ASON Network
As shown in Figure 7-56, a 1+1 VC-4 service is created between SDH NEs 5 and 6 and crosses
the ASON network. The ASON network adopts the intelligent protection or restoration mode.
The SDH network adopts the SNCP protection mode.
Figure 7-56 1+1 VC-4 services between SDH NEs that cross the ASON network
NE1
NE4
NE6
NE5
VC-4
VC-4
NE2
NE3
: ASON NE
: SDH NE
1+1 VC-12 Services Between SDH NEs That Cross the ASON Network
As shown in Figure 7-57, a 1+1 VC-12 service is created between SDH NEs 5 and 6 and crosses
the ASON network. The ASON network adopts the intelligent protection or restoration mode.
The SDH network adopts the SNCP protection mode.
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Figure 7-57 1+1 VC-12 services between SDH NEs that cross the ASON network
NE1
NE4
NE6
NE5
VC-12
VC-12
NE2
NE3
: ASON NE
: SDH NE
VC-4 Services Between ASON NEs and Traditional NEs
As shown in Figure 7-58, a VC-4 service is created between traditional NE5 and ASON NE1.
The ASON network adopts the intelligent protection or restoration mode. The SDH network is
not protected.
Figure 7-58 VC-4 services between ASON NEs and SDH NEs
NE1
NE4
VC-4
NE6
NE5
VC-4
NE2
NE3
: ASON NE
: SDH NE
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VC-12 Services Between ASON NEs and SDH NEs
As shown in Figure 7-59, a VC-12 service is created between SDH NE5 and ASON NE1. The
ASON network adopts the intelligent protection or restoration mode. The SDH network is not
protected.
Figure 7-59 VC-12 services between ASON NEs and SDH NEs
NE1
NE4
VC-12
NE6
NE5
VC-12
NE2
NE3
: ASON NE
: SDH NE
1+1 VC-4 Services Between ASON NEs and SDH NEs
As shown in Figure 7-60, a 1+1 VC-4 service is created between SDH NE5 and ASON NE1.
The ASON network adopts the intelligent protection or restoration mode. The SDH network
adopts the SNCP protection mode.
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Figure 7-60 1+1 VC-4 services between ASON NEs and SDH NEs
NE1
NE4
VC-4
NE6
NE5
VC-4
NE2
NE3
: ASON NE
: SDH NE
1+1 VC-12 Services Between ASON NEs and SDH NEs
As shown in Figure 7-61, a 1+1 VC-12 service is created between SDH NE5 and ASON NE1.
The ASON network adopts the intelligent protection or restoration mode. The SDH network
adopts the SNCP protection mode.
Figure 7-61 1+1 VC-12 services between ASON NEs and SDH NEs
NE1
NE4
VC-12
NE6
NE5
VC-12
NE2
NE3
: ASON NE
: SDH NE
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7.7 Optical-Layer and Electrical-Layer ASON Services
The ASON software provides the wavelength-level ASON services at the optical layer and sub-
wavelength level ASON services at the electrical layer. Hence, customers can implement flexible
service grooming at different layers.
7.7.1 Protection and Restoration Mechanisms for Services
Optical-layer and electrical-layer services have different protection and restoration mechanisms.
Protection and Restoration Mechanism for Optical-Layer ASON Services
Optical-layer ASON services combine protection mechanisms for the traditional WDM network
and the rerouting mechanism for the ASON network, and thus provide the capability of resisting
multiple faults. In the case of the rerouting mechanism for optical-layer ASON services, after
the services are interrupted, rerouting is initiated at the source node. Then, a new trail is set up
through ROADM cross-connections. Figure 7-62 shows the model of the traditional WDM
protection and restoration corresponding to optical-layer silver ASON services of source node
association. For the implementation principles of the client-side protection, see Client 1+1
Protection in the Feature Description.
Figure 7-62 Model of the protection for optical-layer ASON services
Optical-Layer Silver Service of source
node association (Client 1+1 Protection)
OTU
FIU
ROADM
OTU
FIU
Protection and Restoration Mechanism for Electrical-Layer ASON Services
Electrical-layer ASON services combine protection mechanisms for the traditional WDM
network and the rerouting mechanism for the ASON network, and thus provide the capability
of resisting multiple faults. In the case of the rerouting mechanism for electrical-layer ASON
services, after the services are interrupted, new services are created through the cross-
connections on the centralized cross-connect boards or tributary boards.Figure 7-63 shows the
model of the traditional WDM protection and restoration corresponding to typical type of
electrical-layer ASON services. For the implementation principles of the ODUk SNCP
protection, see ODUk SNCP in the Feature Description.
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