WDM System Description

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OpitXNG WDM System Description

1 Network application………Page 3 2 Product functions and features ………..………Page 10 3 Product architecture and capacity………...………Page 37

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Before learn this course, you should have:

Known WDM Basic Principle Studied OTN Basic Knowledge

Reference

OptiXOSN 8800 Product Description OptiXOSN 8800 Hardware Description OptiXOSN 6800 Product Description OptiXOSN 6800 Hardware Description OptiXOSN 3800 Product Description OptiXOSN 3800 Hardware Description

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This chapter introduce

Position in networkss WDM system compositions Classification of channels Networking and applications

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The OptiX OSN 8800 I is mainly applicable to the backbone core layers. It is also applicable

to the metropolitan core layers and metropolitan convergence layers.

The OptiX OSN 8800 I uses dense wavelength division multiplexing (DWDM) technologies

to achieve transparent transmission with multiple services and large capacity.

The OptiX OSN 8800 I can be used to construct the complete OTN end-to-end network

with the OptiX OSN 6800/OptiX OSN 3800, to construct the WDM network with the OptiX BWS1600G/OptiX Metro 6100, and to construct a hybrid network with the OptiX NG-SDH/PTN equipment or data communication equipment. In this way, the OptiX OSN 8800 I can provide complete transport solutions.

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On 2007 huawei launched first OTN WDM system OSN 38006800, which support both

electrical service grooming and photonic cross-connection, both of this equipment using in metro network.

On 2008 huawei plan to launch two kinds of new version equipment there are OSN 8800

and OSN 1800 on is stretching to backbone network and other is stretching to access network try to enhance cross-connect capacity .

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Main functions for OTU is to convert the wavelength between client signals and wdm-side

ITU-T standard signals (G.691/694)

XCS provides flexible cross-connection between the OTU cards, which is the highlights of

OSN8800 compared to traditional WDM equipments.

Main functions for OM is to multiplex the individual channels into main path, OD realizes

the reverse conversion.

OA is used to compensate the line loss or component insertion loss to realize long-distance

transmission.

There are two methods for the management, difference is that ESC depends on OTU cards

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Point-to-point network is the basic application. It is used for end-to-end service

transmission. The other network modes are based on point-to-point mode which is the most basic network.

Chain network with OADM(s) is the suitable topology when it is required to add/drop

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Ring with chain

Tangent rings

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MESH networks have no node bottleneck and ensure unblocked services by alternative

routes during equipment failure. In a MESH network, more than one route is available between two nodes so that the service transmission is highly reliable. As a result, the MESH topology is a mainstream mode for intelligent optical networks. The MESH topology is flexible with good expandability.

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Optical layer technology Electrical layer technology Service access

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BB back bone

MC maintenance control M-D multiple dimension OEQ Optical Equalizer

Single-hop capability 76dB for example G.652 fiber attenuation ratio is 0.25dB/km so

transmission distance about 76/0.25=304 km

XFP 10-Gigabit small form-factor pluggable transceiver eSFP enhance Small Form-Factor Pluggable

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The OptiX OSN 8800 I provides L1 electrical grooming.The OptiX OSN 8800 I supports

two types of cross-connect boards: XCH and XCM. Cross-connect capacity is 1.28T

They support the electrical grooming of ODU2, ODU1, and ODU0.

The OptiX OSN 8800 II provides L1 electrical grooming.The OptiX OSN 8800 II supports

two types of cross-connect boards: XCT and SXM. Cross-connect capacity is 2.56T

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OpitXNG WDM System Description Cross-connection granularity Integrated grooming: GE / ODU1/ ODU2. Distributed grooming: GE / ODU1 / Any(100Mb/s ~2.5Gb/s).

Support L2 electrical layer switching

Full configuration of cabinets of different heights

Item 2.2-m high cabinet 2.6-m high cabinet Quantity of configurable subracks in a ETSI

300 mm middle-column cabinet

4 4

Quantity of configurable subracks in a standard ETSI 300 mm cabinet

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BB back bone

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Transmission distance affect by several facts such as dispersion, OSNR, attenuation and

Non-linear effects

Different accessing rate laser have different dispersion tolerance and different

requirements of OSNR

The value of table is fit to OSN 8800 and OSN 6800 Transmission Distance of OSN 3800

For 10 Gbit/s rate, supports a maximum of 25x22 dB transmission without electrical regenerator.

For 2.5 Gbit/s rate, supports a maximum of 25x22 dB transmission without electrical regenerator.

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FE: Fast Ethernet GE: Gigabit Ethernet

ESCON: Enterprise systems connection FICON: Fiber connection

FC: Fiber channel

HDTV: High Definition TV

DVB-ASI: Digital video broadcasting-asynchronous serial interface DVB-SDI: Digital video broadcasting-serial digital interface

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OTN frame structure 4 rows and 4080 columns

An Optical Transport Network (OTN) is composed of a set of Optical Network Elements

connected by optical fiber links, able to provide functionality of transport, multiplexing, routing, management, supervision and survivability of client signals, according to the requirements given in Rec. G.872

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OTN have abundant overhead bytes

The figure shows the overall electrical layer overhead, include frame alignment overhead,

OTUk layer overhead, ODUk layer overhead, and OPUk layer overhead.

The frame alignment overhead is used for the framing. It is composed of 6-byte frame

alignment signal overhead FAS and 1-byte multiframe alignment overhead MFAS.

OTUk layer overhead supports the transmission operation function connected through one

or more optical channel. It is composed of 3-byte SM, 2-byte GCC0, and 2-byte RES. It is terminated at the OTUk signal assembly and dissemble places.

ODUk layer overhead is used to support the operation and maintenance of the optical

channel. It is composed of 3-byte PM for end-to-end ODUk channel monitoring, 6-level TCM1-TCM6 with 3 bytes respectively, 1-byte TCMACT, 1-byte FTFL, 2-byte EXP, 2-byte GCC1, 2-byte GCC2, 4-byte APS/PCC, and 6-byte reservation overhead. The ODUk overhead is terminated at the ODUK assembly and disassemble places. TC overhead is added at the source, and is terminated at the sink.

OPUk overhead is used to support the customer signal adaptation. It is composed of

1-byte PSI, 3-1-byte JC, 1-1-byte NJO, and 3-1-byte reservation overhead. It is terminated at the OPUk assembly and disassemble places.

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Optical line protection need OLP card after FIU, The OLP aims to protect fibers of the line, which adopts the dual feeding and selective receiving function of the OLP board. This kind of protection is performed between two sites segmentally for the optical signal that is multiplexed. This makes that the working path and the protection path of the protected site must adopt the diverse route. Client side och 1+1 protection:

The client-side 1+1 protection of the OTU uses the dual feeding and the selective receiving

function of the OLP/SCS board to protect the OTU board and units after it.

The client-side 1+1 protection performs the switching based on the client-side ports. And it

has the larger extent of protection that other protection types Intra-borad Och 1+1:

As for the ring networking, the OTU intra-board 1+1 protection uses the separated paths in

the ring to perform the protection, that is, services are transmitted in both the positive and opposite direction of the ring before arriving at the destination node.

As for the chain networking, it is much similar to the optical line protection explained in

chapter one in that the diverse route is required to provide between the adjacent sites. We need to note that in the actual configuration, line fibers of the OTU board that are dually fed are sent to the eastward and westward lines of the node through different equipment types: MUX/DMUX and OA. This process is omitted in this figure.

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SNC/I: Inherent monitoring The trigger conditions are decided by the SM section overhead

status.

SNC/S: Sub-layer monitoring The trigger conditions are decided by the SM and TCM

section overhead status,.

SNC/N: Non-intrusive monitoring The trigger conditions are decided by the SM, TCM and

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The ODUk SPRing protection mainly applies to the ring network with distributed services.

This protection uses two different wavelengths to achieve the protection of multiple distributed services between all stations. Compared with SNCP, multiple services share one protection channel in the ODUk SPRing protection. As a result, the ODUk SPRing

protection effectively saves resources. Currently, the ODU1-level protection can be achieved.

The ODUk SPRing protection applies to ring networks and thus requires the support of a

network protection protocol. The protection adopts dual-ended switching mode, namely, when the receiving end of the working channel fails, both the receive and transmitting ends of the working channel are switched to the protection channels.

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8-channel optical add/drop multiplexing unit with VOA

Realizes the adding/dropping and multiplexing of eight signals and adjusts the input

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The first flash show as the Fix OADM ,3 wavelengths form F to A, D, G, which wavelength

to use depend on the card you design on station A,D,C and F

The second scenarios show us ROADM you can configure the wavelengths’ direction by

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The WSS is the core component. The two types of WSS are MEMS-based WSS and the

LCD-based WSS. The WSS cross-connected a wavelength to a multiplexer corresponding to the designated output port, according to the wavelength routing information. In this way, the WSS accomplish the wavelength grooming function.

In the NG WDM system, there are two types of WSS: WSD9 and WSM9. Considering the

optical channel revertive principle, the WSM9 and the WSD9 are the same in the interior structure and the mechanism. And here, we are talking about the WSD9.

Firstly, the chromatic optical signal is demultiplexed to monochromatic optical signals in

multiplex channels. The in-built VOAs adjust the power of each monochromatic optical signal, and then guide each of the monochromatic signals to different optical multiplexer by controlling the 1 x N (that is N=9 in the figure) optical switch array. Finally, the signals are multiplexed and output. In this way, we can accomplish transmitting of any

monochromatic optical signal to any output port.

Compared with the PLC and the WB, the WSS has the following advantages:

It has better functionality than the WB and the PLC. It can choose a wavelength to be

switched in multiple directions.

The WSS can be directly used as a DMUX, which can add/drop any wavelength at any port.

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The first flash show as the Fix OADM ,3 wavelengths form F to A, D, G, which wavelength

to use depend on the card you design on station A,D,C and F

The second scenarios show us ROADM you can configure the wavelengths’ direction by

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The OptiX OSN 8800 provides grooming on L1 electrical layer. Granularities that can be

groomed at L1 electrical layer are ODU1 signals and ODU2 signals. The electrical layer processing and grooming are added between the client side interface signals and the WDM-side interface signals. Thus, the wavelength utilization of the line is improved. In addition, the OptiX OSN 8800 can connect seamlessly to traditional electrical layer equipment.

The OptiX OSN 6800 provides grooming on L1 electrical layer and L2 electrical layer. Granularities that can be groomed at L1 electrical layer are GE services, ODU1 signals,

ODU2 signals and Any services. Because the electrical layer processing and grooming are added between the client-side interface signals and the WDM-side ones, wavelength utilization of the line is improved. In addition, the OptiX OSN 6800 can therefore connect seamlessly to traditional electrical layer equipment.

The OptiX OSN 6800 supports L2 electrical layer switching based on VLAN and Stack

VLAN. The L4G board realizes basic Ethernet management, including management of the Ethernet private line (EPL) services, Ethernet virtual private line (EVPL) services, the quality of service (QoS), port basic attribute configuration, and test frames.

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TOM board have 6 different scenarios :

Application Scenario 1: Realizes the Conversion between Eight Optical Signals at the Rate between 100 Mbit/s - 2.5 Gbit/s and Four ODU1 Electrical Signals Application Scenario 2: Realizes the Conversion between Eight Optical Signals at

the Rate between 100 Mbit/s - 2.5 Gbit/s and One ODU1 Electrical Signals Application Scenario 3: Realizes the Conversion between Four Optical Signals at

the Rate between 100 Mbit/s-2.5 Gbit/s and Four ITU-T Recommendation compliant WDM Signals

Application Scenario 4: Realizes the Conversion between Seven Optical Signals at the rate between 100 Mbit/s-2.5 Gbit/s and ITU-T Recommendation-compliant WDM Signals

Application Scenario 5: Realizes the Conversion between Six Optical Signals at the rate between 100 Mbit/s-2.5 Gbit/s and ITU-T Recommendation-compliant WDM Signals, and the Dual Fed and Selective Receiving Function on the WDM Side Application Scenario 6: Realizes the Electrical Regeneration of One/Four OTU1

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The OptiX OSN 8800 supports master-slave subrack management. When multiple subracks

are used to form an NE, the master-slave subrack mode is required to realize the unified management.

This ensures less IP resources. Also the ASON function is realized only in one NE. This

ensures easier maintenance and less management overheads.

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The system provides the intelligent power adjustment (IPA) function. When there is a fiber

break on the line, the upstream optical amplifier is shutdown to prevent exposed optical fibers hurting human body.

In the DWDM system, optical fiber break, equipment failure or optical connector removal

may lead to the loss of optical signals on the main optical channel and on the optical auxiliary channels. To prevent exposed optical fibers hurting human body, especially eyes, and to avoid surge of the optical amplifier, the system provides the IPA functions. Where the loss of optical power signals happens on one or more optical trunk sections on the main optical channel and the optical supervisory channels, the system can detect the loss of optical signals on the link and instantly shut down the upstream optical amplifier.

The system provides the automatic level control (ALC) function. When ALC function is

enabled,the increase in the line attenuation in a section causes the decrease in the input power of the amplifier in that section. Its output power and the input and output power of the downstream amplifiers remain the same.

The system provides the automatic power equilibrium (APE). With the APE function, you

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A stable clock is the basic condition for an NE to function properly. The clock must be

configured according to clock configuration principles, to ensure the stability of the clock.

Physical clock ensures frequency synchronization, which is the prerequisite for clock

synchronization.

Physical clock directly uses the features of the physical layer of the synchronous

transmission network. That is, physical clock directly restores clock frequency from the physical optical signals, to ensure the frequency synchronization between the upstream and downstream. In this manner, the services can be transmitted normally.

Table lists the board in the OptiX OSN 8800 I, equipment version, and NM version that

support the physical clock. In addition, the relation between the board type, equipment version, and NM version are provided.

Board Type Equipment

Version NM Version STG OptiX OSN 8800 I V100R002 T2000 V200R008C00 EGSH, SLO16, SLQ64, SLH41, NS2, ND2 T2000 Web LCT V200R008C00

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To deploy the ASON function:

The network topology should be complex enough to provide the redundant routes.

The NE is upgraded to the intelligent NE, which has the GMPLS Control Plane.

The flexible grooming function (optical layer grooming or electrical layer grooming ) is available.

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The OptiX GCP is the ASON software provided by Huawei, which can be applied to the OptiX OSN series products to support the evolution from traditional network to ASON network. The GCP stands for the GMPLS control plane. The GCP complies with the ITU and IETF ASON/GMPLS-related standards.

Compared with the WDM network, the transmission network that applies the new ASON technology shows advantages in service configuration, bandwidth utilization and protection schemes.

In the traditional transmission network, the WDM transmission equipment functions as fibers. Currently, the WDM transmission equipment also carries services. As a result, more requirements are for the operability of the WDM equipment. The traditional network has the following problems:

The service configuration is complex and capacity expansion or service provision takes a

long period.

The bandwidth utilization is of a low rate and low efficiency. In a ring network, half of the

bandwidth should be reserved.

Just a few protection schemes are available and the performance of self-healing protection

is poor.

The ASON has been developed to solve these problems. This technology involves signaling switching and a control plane to enhance its network connection management and recovery capability. It supports end-to-end service configuration and the service level agreement (SLA).

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Product architecture Board list

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The unique innovation of OSN8800 system is the two-level traffic grooming infrastructure

integrating dynamic optical cross-connect (Multi-degree ROADM) flexible electric grooming (Any ADM).

L0 (Optical layer).

Agile photonic layer has multi-degree wavelength cross-connect capacity, and therefore provides the ability to route wavelengths to speed up service delivery and reduce the cost of O-E-O conversion.

L1(High order electrical layer).

In the case of the electrical-layer grooming scheme, the OptiX OSN 8800 supports L1 grooming to groom ODU0, ODU1 and ODU2 services.

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Board area: All service boards, SCC boards and XCS boards are in this area. Totally 49slots

are available.

Fiber cabling area: Fiber jumpers from the ports on the front panel of the boards are

routed to the area before reaching the matched side of the cabinet.

Fan tray assembly: This area contains 3 fans for ventilation and heat dissipation of the

subrack. There are altogether four subrack indicators in different colors on the fan tray assembly to indicate the status of running.

The EFI1, EFI2 and ATE boards are the interface board of OSN 8800, they implement

functions, such as alarm input, alarm output, and alarm cascading, to monitor the remote external systems.

The AUX board provides the inter-board and inter-subrack communication. The AUX board

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IU1-IU8, IU12-IU27, IU29-IU36 are for service boards. IU37 is for the EFI2.

IU38 is for the EFI1. IU48 is for the ATE.

IU39, IU40, IU45 and IU46 are for the PIU. IU41 and IU43 are for the AUX.

IU42, IU44 and IU47 are reserved for future use. IU28 is for the active SCC.

IU11 is available for the standby SCC or the other service boards. IU9 and IU10 are for the XCS

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Note:

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The unique innovation of OSN 6800 system is the three-level traffic grooming

infrastructure integrating dynamic optical cross-connect (Multi-degree ROADM) flexible electric grooming (Any ADM) embedded L2 switch processing capability.

L0 (Optical layer).

Agile photonic layer has multi-degree wavelength cross-connect capacity, and therefore provides the ability to route wavelengths to speed up service delivery and reduce the cost of O-E-O conversion.

L1(High order electrical layer).

Huawei GE ADM is the first commercialized integrated GE transport and switching system in the industry designed with Huawei own patents. Today, Huawei has extended ADM solution to any service, Any ADM/MADM solution implements any data channel end to end automated creation, performance monitoring, fault detection, protection and traffic grooming between different wavelengths across complicated network topologies.

L2(Low order electrical layer).

Embedded LAN switching processor implements local Ethernet traffic

aggregation, including convergence of n*GE to m* GE (m<n) or N*GE to 10GE LAN interface. It increases wavelength bandwidth utilization.

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The EFI and AUX boards are the interface board of OSN 6800.

The EFI provides various functional interfaces such as management interfaces,

inter-subrack communication interfaces, and alarm input/output interfaces.

The AUX board provides various functional interfaces such as inter-subrack

communication interfaces, NM interface and NM cascading interface.

NM_ETH1/2: It is NM interface or NM cascading interface ETH: It is for master/slave subrack communication

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The slot 17 can be used for the common boards if the SCC 1+1 protection is not

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Different slots have different pairs of backplane bus connected to the XCS. The OSN 6800 supports the cross-connect of GE, ANY, ODUk(ODU1, ODU2) GE and ODU1 support both centralized and inter-board (distributed)

cross-connect.

ODU2 only supports the centralized cross-connect.

ANY only supports the inter-board (distributed) cross-connect.

Thought:

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The AUX board is the interface board of OSN 3800, it implements functions such as

alarm input, alarm output and alarm cascading.

NM_ETH1/2: It is NM interface or NM cascading interface. EXT: The testing connectors

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IU1 and IU11 can either hold two OADM boards respectively, or hold one service

board as IU11.

Full MESH cross-connection between IU2～IU5, supports the electrical grooming

of: GE services, ODU1 services and Any services (100Mbit/s～2.5Gbit/s)

The OptiX OSN 3800 provides alternating current (AC) and direct current (DC)

power supplies. The arrangement of boards of IU6, IU7, IU8, and IU9 is different for the two power supply modes.

In DC mode

IU6 and IU7 are for the PIU. IU8 and IU9 are for the SCC。IU9 is for the active SCC. IU8 is available for either the standby SCC or the OADM board.

In AC mode

IU6，IU7，IU8 are for two APIU boards. The IU9 is for the SCC. The IU8 is occupied. The standby slot for the SCC is not available.

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Here list some types of OTU but not all.

Indicator Name Color

STAT Board hardware status indicator

Red, green

ACT Service active status indicator Green PROG Board software status

indicator

Red, green

SRV Service alarm indicator Red, green, yellow

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Tributary cards only have clients side

NS2 NS2 CLASS 1 LASER PRODUCT STAT ACT PROG SRV O U T IN

Line card only has wdm side

All tributary units and line units provide four indicators

STAT Board hardware status indicator

Red, green ACT Service active status indicator Green PROG Board software status

indicator

Red, green SRV Service alarm indicator Red, green, yellow

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Tributary units only access client service and each of them have cross connect chips can

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TN11ND2 is 20Gbit/s card, single card outputs two individual wavelengths. TN51NQ2 is 40Gbit/s cards with four wavelength output.

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All Optical multiplexer and demultiplexer unit provide four indicators：

STAT Board hardware status indicator Red, green ACT Service active status indicator Green PROG Board software status indicator Red, green SRV Service alarm indicator Red, green, yellow

D40 D40 STAT ACT PROG SRV CLASS 1 LASER PRODUCT D01 D02 D03 D04 D05 D06 D07 D08 D09 D10 D11 D12 D13 D14 D15 D16 D17 D18 D19 D20 D21 D22 D23 D24 D25 D26 D27 D28 D29 D30 D31 D32 D33 D34 D35 D36 D37 D38 D39 D40 196.00 195.90 195.80 195.70 195.60 195.50 195.40 195.30 195.20 195.10 195.00 194.90 194.80 194.70 194.60 194.50 194.20 194.10 194.40 194.30 194.00 193.90 193.80 193.70 193.60 193.50 193.20 193.10 193.40 193.30 193.00 192.90 192.80 192.70 192.60 192.50 192.20 192.10 192.40 192.30 D 1 5 D 1 6 D 1 7 D 1 8 D 1 9 D 2 0 D 2 1 D 2 2 D 2 3 D 2 4 D 1 3 D 2 5 D 2 6 D 1 4 D 0 1 D 0 2 D 0 3 D 0 4 D 0 5 D 0 6 D 0 7 D 0 8 D 0 9 D 1 0 M O N D 1 1 D 1 2 IN D 2 9 D 3 0 D 3 1 D 3 2 D 3 3 D 3 4 D 3 5 D 3 6 D 3 7 D 3 8 D 2 8 D 3 9 D 4 0 D 2 7

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All Reconfigurable OADM units provide four indicators.

STAT Board hardware status indicator Red, green ACT Service active status indicator Green PROG Board software status indicator Red, green SRV Service alarm indicator Red, green, yellow

R M U 9 R M U 9 S T A T A C T P R O G S R V C L A S S 1 L A S E R P R O D U C T M O N O M O N I O U T E X P I T O A R O A A M 1 A M 2 A M 3 A M 4 A M 5 A M 6 A M 7 A M 8

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Booster amplifier

_{Line Amplifier}

_{Pre-amplifier}

M 4 0 OTU OTU M 4 0 M 4 0 OTU OTU M 4 0 M U X D M U X OA OA OA

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The TN11OAU1/ OBU1 board does not support adjustment of the input optical power,

whereas the TN12OAU1/ OBU1 board does.

TN12OAU1/ OBU1 has VO/VI port on front panel

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Indicators: There are eight indicators on the front panel.

Board hardware status indicator (STAT) - dual-colored (red, green) Service active status indicator (ACT) - green

Board software status indicator (PROG) - dual-colored (red, green) Service alarm indicator (SRV) - triple-colored (red, green, yellow) System power supply indicator (PWRA)- dual-colored (red, green) System power supply indicator (PWRB)- dual-colored (red, green) Protection power indicator (PWRC)- dual-colored (red, green) Alarm cut-off indicator (ALMC)- yellow

Buttons: There are three buttons on the front panel. Table lists the

function of each button.

Button Function

RESET Used to reset the SCC.

ALM CUT Used to clear the sound alarm.

LAMP TEST Used to test all the indicators in the subrack.

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XCH/XCM is fit for OSN 8800. XCS is fit for OSN 6800

STG of OSN 8800 is different with OSN 6800’s. STG of OSN 8800 need work with

interface board STI.

STG and STI board of OSN 8800

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1.28Tbit/s / 2.56Tbit/s Optical Transponder Unit Tributary Unit and Line Unit Cross-connect Unit

Optical Multiplexer and Demultiplexer Unit Optical Add and Drop Multiplexing Unit Optical Amplifying Unit

System Control and Communication Unit Optical Supervisory Channel Unit

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Type Scheme Function

SNCP

ODUk SNCP protection

It uses the dual fed and selective receiving function of the electrical layer grooming, to protect the line board and the OCh fibers. The cross-connect granularity is ODU1 and ODU2 signals.

Tributary SNCP

Protects the tributary service by using the dual-fed and selectively-receiving function at the electrical

crossconnect layer. The cross-connect granularity is ODU1 signals and ODU2 signals.

ODUk

SPRing ODUk SPRing

It applies to the ring networks. This protection uses two different channels to achieve the protection of one channel of service between all stations.

OWSP OWSP

It applies to the ring networks. This protection uses two different channels to achieve the protection of one channel of service between all stations.

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