NE20E-S V800R022C00SPC600 Configuration Guide
WDM Interface Configuration
Wavelength division multiplexing (WDM) is a technology used for long-distance transmission over metropolitan area networks (MANs) and wide area networks (WANs)
Overview of WDM Interfaces
This section describes basic concepts of the optical transport network (OTN) and WDM.
Overview of WDM
Wavelength-division multiplexing (WDM), a technology used in the MAN and WAN, is used to transmit two or more optical signals of different wavelengths through the same optical fiber. A WDM system uses a multiplexer at the transmitter to join multiple optical carrier signals of different wavelengths (carrying different information) together on a single optical fiber, and a demultiplexer at the receiver to split the optical carrier signals apart. Then, an optical receiver further processes and restores the optical carrier signals to the original signals.
WDM interfaces supported by the NE20E consist of two interfaces, namely the controller WDM interface and its corresponding GE interface. Parameters related to the optical layer and electrical layer are configured in the controller WDM interface view, and all service features are configured in the GE interface view. The mapping mode of service signals on WDM interfaces is Ethernet over OTN.
Overview of OTN
Currently, the Synchronous Digital Hierarchy over Synchronous Optical Network (SDH/SONET) and WDM networks are usually used as transport networks. SDH/SONET processes and schedules services at the electrical layer and WDM processes and schedules services at the optical layer. With the increasing of data services, more and more bandwidths are required. The SDH/SONET network cannot meet the requirements on cross scheduling and network scalability. In addition, operators require the WDM network of high maintainability, security, and service scheduling flexibility. As a result, the OTN is developed to solve the problems.
The OTN technology applies the operability and manageability of SDH/SONET networks to the WDM system so that the OTN acquires the advantages of both the SDH/SONET network and the WDM network. In addition, the OTN technology defines a complete system structure, including the management and monitoring mechanism for each network layer and the network survival mechanism of the optical layer and electrical layer. In this manner, operators' carrier-class requirements are really met.
The OTN, which consists of optical network elements connected through optical fiber links, provides the transport, multiplexing, routing, management, monitoring, and protection (survival) capabilities to optical channels that are used to transmit client signals. The OTN features that the transport settings of any digital client signal are independent of specified client features, namely, client independence. Optical Transport Hierarchy (OTH) is a new connection-oriented transport technology that is used to develop the OTN. Owing to the great scalable capability, the OTN is applicable to the backbone mesh network. Ideally, the future transport network is an all OTN network. Compared with SDH networks, the OTN is the optical transport network of the next generation.
- Higher FEC capability
- Tandem Connection Monitoring (TCM) of more levels
- Transparent transport of client signals
- Measurable data exchange
FEC Overview
The communication reliability is of great importance to communication technologies. Multiple channel protection measures and automatic error correction coding techniques are used to enhance reliability.
The OTU overhead of an OTN frame contains FEC information. FEC, which corrects data by using algorithms, can effectively improve the transport performance of the system where the signal-to-noise ratio (SNR) and dispersion are limited. In this manner, the investment cost on the transport system is reduced accordingly. In addition, in the system using FEC, the receiver can receive signals of a lower SNR. The maximum single span is enlarged or the number of spans increases. In this manner, the total transmission distance of signals is prolonged.
TTI Overview
Trail trace identifier (TTI) is a byte string in the overhead of an optical transport unit (OTU) or an optical data unit (ODU). Like the J byte in the SDH segment overhead, the TTI identifies the source and destination stations to which each optical fiber is connected to prevent incorrect connection. If the received TTI differs from the expected value, a TIM alarm is generated.
OTU overhead: contains information about the transmission function of optical channels, and defines FAS, MFAS, GCC0, and SM (such as TTI, BIP-8, BDI, BEI/BIAE, and IAE) overheads. Among these overheads, TTI is a 64-byte string monitoring the connectivity of the OTU segment.
ODU overhead: contains information about the maintenance and operation function of optical channels, and defines TCM, PM, GCC1/GCC2, APS/PCC, and FTFL overheads. Among these overheads, TCM monitors the serial connection, and PM monitors ODU paths.
Configuring WDM Interfaces
The physical layer of a WDM interface is configured in the WDM interface view, and service parameters are configured in the GE interface view.
Configuring Optical Parameters
Optical parameters are configured in the WDM interface view to allow the WDM interfaces at both ends of an optical fiber to communicate at the physical layer.
Context
Optical parameters of WDM interfaces must be configured to allow the WDM interfaces at both ends of an optical fiber to communicate at the physical layer. Service parameters can be configured only after optical parameters are configured. Currently, optical parameters of WDM interfaces on the NE20E are FEC and TTI.
FEC contained in the OTU overhead of the OTN frame is used for data error correction by using algorithms. NE20E supports two FEC modes: standard G.709 FEC and enhanced FEC. Compared with standard G.709 FEC, enhanced FEC improves algorithms by using the FEC code type with stronger forward error correction capability.
TTI is a byte string in the overhead of an OTU and or an ODU. Like the J byte in the SDH segment overhead, the TTI identifies the source and destination stations to which each optical fiber is connected to prevent incorrect connection. If the received TTI differs from the expected value, a TIM alarm is generated.
Procedure
- Run system-view
The system view is displayed.
- Run interface interface-type interface-number
The interface view is displayed.
- Run set transfer-mode otn
The interface is configured to work in OTN mode.
- Run optical-tx-power { attenuation attenuation-value | target target-value }
The attenuation value and optical power for an optical module is configured.
- Run quit
Return to the system view.
- Run controller wdm interface-number
The interface view is displayed.
- Run fec { standard | none | enhanced-i-4 | enhanced-i-7 | enhanced | lhaul-sd }
The FEC mode is configured for the WDM interface.
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Two interconnected WDM interfaces must have the same FEC configurations.
- Run tti { otu | odu-pm } { expected | sent } 64byte-mode value
The TTI is configured for the OTU or ODU.
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The value on the sending end must be the same as the expected value set on the peer end of an optical fiber.
- Run otn sd-threshold sd-threshold
The alarm thresholds on attenuation of optical transmission signals are set.
- (Optional) Run otn prefec-tca trigger-threshold trigger-coefficient trigger-power trigger-interval trigger-time-interval [ recover-threshold recover-coefficient recover-power ] [ recover-interval recover-time-interval ]
Configure an alarm threshold and detection interval for FEC bit error ratio detection on an optical transport network (OTN).
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To configure an alarm threshold and detection interval for FEC bit error ratio detection on an OTN, run the otn prefec-tca command. By default, FEC bit error ratio detection is enabled. The default alarm thresholds and detection intervals are used. If the FEC bit error ratio exceeds a specified threshold, the device reports an FEC bit error ratio alarm to the NMS. When the FEC bit error ratio falls below a specified threshold, the device reports an FEC bit error ratio clear alarm to the NMS.
- Run span span-value
The span to estimate the OSNR of a line are set.
When an optical amplifier (OA) resides between two connected OTN interfaces, run the span command to set a span based on the network situation, so that the non-linear OSNR of a line can be more accurately estimated to facilitate line adjustment.
- Run mapping-path { opu2-standard | opu2-non-standard | opu2e }
A mapping mode for client signals is configured.
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The undo shutdown, loopback, clock, and ptp command configurations have been cleared from the Ethernet interface that the WDM interface corresponds to.
Interfaces that have different mapping modes cannot communicate with each other. The mapping-path command can be run only on 10GE OTN subcards.
- Run commit
The configuration is committed.
Configuring Service Parameters
Configuring service parameters in the Ethernet interface view allows the interface to bear services.
Context
Before configuring service parameters, enter the Ethernet interface view. The configuration procedure is the same as that for 10GE LAN interfaces. For details, see Ethernet Interface Configuration.
Configuring OTN Delay Measurement
Configuring OTN delay measurement allows you to obtain the round-trip delay on an OTN.
Context
To obtain an OTN delay, configure OTN delay measurement. Figure 1-542 shows an OTN delay measurement network.
This configuration is performed on Device A (source) and Device B (sink).
Configuration Examples for WDM
Example for Configuring DWDM Services
This section provides an example for configuring DWDM services.
Networking Requirements
As shown in Figure 1-543, colored optical modules are installed on router interfaces to directly output colored optical signals that comply with ITU-T G.694. The interfaces send optical signals with different wavelengths directly to the MUX of a DWDM device. The MUX multiplexes optical signals with specific wavelengths from multiple interfaces and then sends the signals to the DMUX. After receiving the signals with different wavelengths from the same MUX interface, the DMUX demultiplexes them and sends them through different interfaces. In this way, the optical signals are transmitted to the colored optical module interfaces with the corresponding wavelengths on the receive end.
Interfaces 1 through 4 in this example represent GigabitEthernet0/1/0, GigabitEthernet0/1/1, GigabitEthernet0/1/0, and GigabitEthernet0/1/1, respectively.
Configuration Roadmap
- Configure a transmission mode for specified interfaces.
- Set channel IDs for the center wavelengths of the optical modules on the interfaces.
- Check the center wavelengths of the optical modules on the interfaces.
Procedure
- Configure a transmission mode for the specified interfaces on DeviceA and set channel IDs for the center wavelengths of the corresponding optical modules.
<HUAWEI> system-view [~HUAWEI] sysname DeviceA [*HUAWEI] commit [~DeviceA] interface GigabitEthernet0/1/0 [~DeviceA-GigabitEthernet0/1/0] set transfer-mode otn [*DeviceA-GigabitEthernet0/1/0] wavelength-channel 48 [*DeviceA-GigabitEthernet0/1/0] quit [*DeviceA] interface GigabitEthernet0/1/1 [*DeviceA-GigabitEthernet0/1/1] set transfer-mode otn [*DeviceA-GigabitEthernet0/1/1] wavelength-channel 48 [*DeviceA-GigabitEthernet0/1/1] quit [~DeviceA] commit
- Configure a transmission mode for the specified interfaces on DeviceB and set channel IDs for the center wavelengths of the corresponding optical modules.
<HUAWEI> system-view [~HUAWEI] sysname DeviceB [*HUAWEI] commit [~DeviceB] interface GigabitEthernet0/1/0 [~DeviceB-GigabitEthernet0/1/0] set transfer-mode otn [*DeviceB-GigabitEthernet0/1/0] wavelength-channel 49 [*DeviceB-GigabitEthernet0/1/0] quit [*DeviceB] interface GigabitEthernet0/1/1 [*DeviceB-GigabitEthernet0/1/1] set transfer-mode otn [*DeviceB-GigabitEthernet0/1/1] wavelength-channel 49 [*DeviceB-GigabitEthernet0/1/1] quit [~DeviceB] commit
- Verify the configuration.
GigabitEthernet0/1/0 on DeviceA is used as an example.
You can run the display interface command to check the effective transmission mode and center wavelength of the specified interface. The mapping between the center wavelength and channel ID of the optical module can be queried through the display wavelength-capability command.
[~DeviceA] display interface GigabitEthernet0/1/0
GigabitEthernet0/1/0 current state : UP (ifindex: 521) Line protocol current state : DOWN Link quality grade : GOOD Description: Route Port,The Maximum Transmit Unit is 1500 Internet protocol processing : disabled IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is xxxx-xxxx-xxxx The Vendor PN is LTF8502-BC+ The Vendor Name is Hisense Port BW: 10G, Transceiver max BW: 10G, Transceiver Mode: MultiMode WaveLength: 1547.715nm, Transmission Distance: 300m Rx Power: -2.90dBm, Warning range: [-9.901, -1.000]dBm Tx Power: -2.03dBm, Warning range: [-7.300, -1.000]dBm Loopback: none, OTN full-duplex mode, Pause Flowcontrol: Receive Enable and Send Enable Last physical up time : 2021-10-11 09:21:18 Last physical down time : 2021-10-11 09:20:20 Current system time: 2021-10-11 16:47:55 Statistics last cleared:never Last 300 seconds input rate: 79 bits/sec, 0 packets/sec Last 300 seconds output rate: 79 bits/sec, 0 packets/sec Input peak rate 127 bits/sec, Record time: 2021-10-11 09:22:08 Output peak rate 127 bits/sec, Record time: 2021-10-11 09:22:08 Input: 293740 bytes, 895 packets Output: 293740 bytes, 895 packets Input: Unicast: 0 packets, Multicast: 895 packets Broadcast: 0 packets, JumboOctets: 0 packets CRC: 0 packets, Symbol: 0 packets Overrun: 0 packets, InRangeLength: 0 packets LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets Fragment: 0 packets, Undersized Frame: 0 packets RxPause: 0 packets Output: Unicast: 0 packets, Multicast: 895 packets Broadcast: 0 packets, JumboOctets: 0 packets Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets System: 0 packets, Overruns: 0 packets TxPause: 0 packets Local fault: normal, Remote fault: normal. Last 300 seconds input utility rate: 0.01% Last 300 seconds output utility rate: 0.01%[~DeviceA] display wavelength-capability interface GigabitEthernet0/1/0
----------------------------------------------- index Frequency(THz) Wavelength(nm) ----------------------------------------------- 01 196.050 1529.163 02 196.000 1529.553 03 195.950 1529.944 04 195.900 1530.334 05 195.850 1530.725 06 195.800 1531.116 07 195.750 1531.507 08 195.700 1531.898 09 195.650 1532.290 10 195.600 1532.681 11 195.550 1533.073 12 195.500 1533.465 13 195.450 1533.858 14 195.400 1534.250 15 195.350 1534.643 16 195.300 1535.036 17 195.250 1535.429 18 195.200 1535.822 19 195.150 1536.216 20 195.100 1536.609 21 195.050 1537.003 22 195.000 1537.397 23 194.950 1537.792 24 194.900 1538.186 25 194.850 1538.581 26 194.800 1538.976 27 194.750 1539.371 28 194.700 1539.766 29 194.650 1540.162 30 194.600 1540.557 31 194.550 1540.953 32 194.500 1541.349 33 194.450 1541.746 34 194.400 1542.142 35 194.350 1542.539 36 194.300 1542.936 37 194.250 1543.333 38 194.200 1543.730 39 194.150 1544.128 40 194.100 1544.526 41 194.050 1544.924 42 194.000 1545.322 43 193.950 1545.720 44 193.900 1546.119 45 193.850 1546.518 46 193.800 1546.917 47 193.750 1547.316 48 193.700 1547.715 49 193.650 1548.115 50 193.600 1548.515
Configuration Files
DeviceA configuration file
# sysname DeviceA # interface GigabitEthernet0/1/0 set transfer-mode otn wavelength-channel 48 # interface GigabitEthernet0/1/1 set transfer-mode otn wavelength-channel 48 # return
DeviceB configuration file
# sysname DeviceB # interface GigabitEthernet0/1/0 set transfer-mode otn wavelength-channel 49 # interface GigabitEthernet0/1/1 set transfer-mode otn wavelength-channel 49 # return