Brief Introduction

ZXWM M920 is a member of iOTN series targeting long-haul backbone applications in regional and national area. It features super-large capacity, ultra-long haul, and smooth upgradeability. It offers full-rate optical access capability from STM-1/OC-3 to 100GE, as well as complete access capability for other services, such as POS, ATM, GE/10GE, ESCON, FICON, FC and PDH. ZXWM M920 Cabinet and sub-rack are illustrated in Figure 1.

Features

• Large Capacity and Scalable Platform
  

ZXWM M920 support 80×100G transport capacity, which means the maximum transport capacity of each fiber can reach 8Tb/s. It is 10 times and 2.5times of 10G and 40GWDM system. Thus, it can satisfy the operator’s growing bandwidth demands.

ZXWM M920 supports 80/96×10G/40G at the same time. It can be upgrade from 40 wavelengths to 80 wavelengths and from 48 wavelengths to 96 wavelengths smoothly.

• Ultra Long Haul Applications

With excellent ultra long haul transmission techniques, ZXWM M920 supports for 5000km transmission without electrical regeneration and 300Km single-span transmission for 10G system and 1500km transmission without electrical regeneration for 40G system and  over 3500km transmission without electrical regeneration for 100G system.

• Single 100Gbit/s system 

ZXWM M920 can support single 100Gbit/s system, and has following features:

Support 80*100GE transmission and the capacity of at most 8Tbit/s;

PM-QPSK coding with SD-FEC has good OSNR tolerance and can restrain the non-linear effect well. The transmission distance can be over 3500KM without the REG with 50GHz spacing. 

Embedded high-speed DSP technology realizes the compensation of dispersion and PMD, so that the additional boards of PMD and CD compensation are reduced.

PM-QPSK coding can restrain the non-linear effect well. With DSP technology, the PMD tolerance can support 60ps and CD tolerance can support +/-70000ps/nm.

• 40G Transmission

40Gb/s system supports P-DPSK, RZ-DQPSK, PM-QPSK modulation. PM-QPSK solution adopts advanced DSP processing technology can support 60ps of PMD tolerance and +/-50,000ps/nm of chromatic dispersion tolerance. Transmission distance can reach over 1,500 kilometers without electrical relay, which saves the investments and facilitates the maintenance.

• Intelligent Optical Network WASON

ZXWM M920 supports GMPLS/WASON control plane load, can realize rapid automatic route discovery. Strong ability for automatic resource discovery. Versatile resource management functions and fast end-to-end service provisioning and so on.

• Powerful Electrical-Optical Mixed Switching

ZXWM M920 is an intelligent OTN product with the most powerful electrical-optical mixed switching function, it can simultaneously support multi-granularity services dispatching in optical layer, electrical layer and the data L2 switching; optical-layer, electrical-layer and L2 layer can work together to randomly dispatch services from electrical layer to optical layer, which improves network flexibility.

• IWF (Integrated Wavelength Feedback) Patented Technique

Combination of patented wavelength centralized monitoring technique and precise temperature control further guarantees the wavelength stability of 50GHz wavelength spacing system. Realize smooth system upgrading from 100GHz spacing to 50GHz spacing.

• APO (Auto performance Optimization): Secure and Reliable Optical Power Auto-balancing Technique

Embedded sub-network-level performance optimization is used to automatically establish and retain the optimized status of system optical performance, as exemplified by OSNR, maintain optimal overall system performance, drive down maintenance cost and improve maintenance efficiency, applicable to WDM system with frequently changing fiber parameters. 

• Leading Protection Schemes

ZXWM M920 can provide multiple and effective protection modes: Optical subnet connection protective switchover (OSNCP); Unidirectional optical line protective switchover (ULSR); Unidirectional optical channel protective switchover (UPSR); Bidirectional optical line share protective switchover (BLSR); Bidirectional optical channel share protective switchover (BPSR) etc. which with the switching time shorter than 50ms. 

• Power Service Access and Aggregation Ability
  

ZXWM M920 adopts an open design. The accessed optical signals can be converted to ITU-T G.692 recommendation compliant wavelength signals for output by employing optical/electric/optical conversion technology. 

It supports optical signals in multiple formats, such as STM-N (N=1, 4, 16, 64,256), POS, GE/10GE/100GE, ATM, ESCON, FICON and FC, which protect users’ benefit and provide an ideal means for network expansion. 

ZXWM M920 also can multiplex low-rate services into 100GE, 40G, 10G or 2.5G rates transparently to improve the availability of system wavelength.

• ULH Design. Reduce the Amount Of Regenerators

ZXWM M920 employs the ultra-long-haul distance optical source technologies to realize ULH transmission without regenerators, which can reduce CAPEX and OPEX.

With different optical transponder units (OTU), EDFA, FEC, AFEC and SD FEC technologies, RZ/SRZ coding technology, P-DPSK/DQPSK/PM-QPSK coding technology, distributed Raman amplifier(RMAN), Remote pumped optical amplifier (RPOA)  and dispersion management technology, ZXWM M920 can perform super long non-electric relay transmission from several kilometers up to thousands of kilometers.

• Large Capacity. Fully Satisfying Service Explosion In Future

ZXWM M920 can provide 1920/3840/8000Gbit/s transmission capacity, fully satisfying the ever-growing requirements on bandwidth.

ZXWM M920 can support 80*100GE transmission and the capacity of at most 8Tbit/s;

Product Architecture

ZXWM M920 is divided into a hardware system and a software system, which are independent of each other.

According to functional modules, ZXWM M920 hardware structure can be divided into service access and convergence system, group Mux/De-Mux subsystem, OA subsystem, supervision subsystem, protection subsystem, optical-layer management subsystem, cross-connect subsystem, RPOA subsystem and power subsystem. Their composition and roles are as follows:

• Service access and convergence system

It consists of optical transponder boards and convergence boards. It supports various functions such as service access, service convergence, FEC coding/decoding, and performance monitoring for

• Intelligent Traffic Grooming

ZXWM M920 provides intelligent traffic grooming – DSS (Distributed Service Switching platform).

One DSS group consists of four cards. The non-blocking service switching among these four cards can realize sub-wavelength service dispatching during multiple directions. The switching granularity can be ODU0 or ODU1. Total switching capacity of each DSS group is 80G and single sub-rack can support multiple DSS group.

• Mux/De-Mux subsystem

It consists of add/drop multiplexing unit, group De-Mux unit and Mux/De-Mux unit. Its functions are Mux/De-Mux and add/drop multiplexing.

• Optical amplification subsystem

It consists of EOA board, DRA board, LAC board and DCM module. It supports optical signal amplification, dispersion compensation, and add/drop of supervision channel.

Optical fiber amplifier of ZXWM M920 system is based on single-stage mode or double-stage mode. Enhanced Optical Booster Amplifier (EOBA),Enhanced Optical Line Amplifier (EOLA) and Enhanced Optical Preamplifier (EOPA) is based on single-stage mode , and Enhanced Optical Node Amplifier(EONA) is based on double-stage mode. EOBA,EOLA and EONA use dual pumps, and EOPA use single pump or dual pumps. The wavelength of single pump source is 980nm, and the wavelengths of dual pump sources are 980nm and 1480nm. Gain flatness is ±1dB. Extra metal ion and Gain Flattening Filter (GFF) can be added to ensure OA gain flatness.

• Supervision subsystem

It consists of SNP board, SOSC board, SCC board, and SEIA board. It provides communication bus, EMS management interface, and supervision channel transmission.

• Protection subsystem

It supports 1+1 protection and 1:N shared protection for channel and multiplex section.

• Cross-connect subsystem

It consists of CSUB board, COMB board, CQ2 board, LQ2 board, and LS2 board. It provides clocks to the system and supports service access, cross-connect and Mux/De-Mux.

• Optical layer management subsystem

It consists of OWM board, OPM board, DCU board, EOPM board and EOWM board. It monitors important performance parameters of optical signal, including wavelength, optical power, and optical signal-noise ratio.

• RPOA subsystem

It consists of RPU board and RGU module. It provides ZXWM M920 equipment with ultra long-haul single-span transmission with no line power supply.