WDM Technology and ZTE Integrated Solution

Since the inception of WDM (Wavelength Division Multiplexing) technology, it has found wide applications rapidly as it optimizes the cost-effectiveness in tackling fiber shortage and long-haul transmission. WDM technology has achieved a dominating position in the global trunk line transmission market, furthermore, its two development trends DWDM (Dense WDM) and CWDM (Coarse WDM) adopted in MAN construction have become increasingly popular due to the following advantages:

Advantages of ZTE WDM technology
Backed by strong R&D team, guided by a customer oriented approach and focusing on network construction cost and operation efficiency, ZTE keeps on launching advanced solutions, providing perfect and excellent services for the customers by. After developing WDM technology and promoting it for more than a decade, ZTE has a whole series of WDM products to deploy into backbone network, MAN and access network.

• ZXWM M900 trunk line DWDM system
  Large capacity and ultra-long-haul DWDM equipment. It can multiplex up to 160 wavelength in a single core fiber, and its total transmission capacity can reach to 1600Gb/s. 
  The modular design enables a capacity scale designs of 400Gb/s, 800Gb/s and even 1600Gb/s. The system adopts such flexible design as MUX/DMUX+Interleaver+C/L passband OMU/ODU to ensure smooth scalability and capacity expansion.
  Utilizie advanced technologies such as FEC/EFEC, RAMAN amplifier, RZ coding and dispersion management that the 160 wavelength⊙10Gb/s system can fulfill ultra-long-haul relay transmission over 5000km (54⊙27dB) without regenerator.
  Accommodate integrated services, supporting STM-N, GE, FE, Fiber Channel, ESCON, Digital Video and FICON; it offers powerful access and convergence capabilities for low-rate services and could converge up to eight Any⊙Any rates traffic onto STM-16/STM-64. 
  Provide easy maintainability by fully utilizing such advanced techniques as a wide range of optical power control, wavelength stabilizing, on-line adjustment of wavelength and power, on-line performance test, built-in optical performance test, fault location function, OTN overhead test.
  Offer flexible industrial-leading protection solution, consisting of 6 protection modes for optical layer and service layer. They are 1+1 path protection, two-fiber bi-directional path shared protection (BPSR), two-fiber bi-directional multiplexing section shared protection, sub-network connection protection, 1+1 multiplex section protection, equipment-side 1:16 OTU protection.
  Industry-leading intelligent amplification and power control techniques. In addition to automatic gain locking and EDFA gain variable techniques, the system can balance multi-power energy from path to multiplex section via Line Attenuation Compensation (LAC), Variable Gain Slope Compensation (VGSC), path power pre-balancing (VMUX), Dynamic Gain Equalization (DGE), High-power Optical Booster Amplifier (HOBA) techniques.
  Flexible networking modes: chain, star, cross, two-ring tangent and two-ring intersection networks, applicable for different network layout.
• ZXMP M800 Metro DWDM system
  It is OADM (Optical Add/Drop Multiplexer) equipment based on ZXWM M900 designed for MAN and local backbone transmission network. It can realize configurable optical add/drop multiplexing, wavelength add/drop or transparent transmission, and rapid protection switching.
  Offer 80 optical transmission channels with a maximum capacity of 800Gb/s. The nodeˇs wavelength is upgradeable from 1 to 32, 40, 80; itˇs able to add/drop or multiplex any number of wavelengths at any node to satisfy dynamic requirements of service dispatching;
  Capable of transporting overall integrated services. It offers open protocols and rich client layer interfaces, which can carry various services typical of a metro network, including STM-N (N=1,4,16,64), GE, FE, Fiber Channel, ESCON, Digital Video and FICON; it also offers highly efficient and flexible sub-rate convergence, including 4⊙155/622 Mb/s, 2⊙GE, 4⊙2.5 Gb/s and multiple channel FE convergence and could realize multiple service hybrid multiplexing. 
  Offer flexible industrial-leading protection solution, consisting of 6 protection modes for optical layer and service layer.
  Industry-leading intelligent amplification and power control techniques.
  Flexible networking modes.
• ZXMP M600 Metro CWDM system
  Features economical WDM system for short distance with its low cost, large capacity, service transparency and easy scalability. It can be widely applied at the convergence/access layer in a metro network, and at the metro backbone layer in small to medium cities. 
  Low cost. Typically, its cost is only one third of other DWDM products.
  Transparent transmission of integrated services. It supports services with variable rates from 10M to 2.5G and various protocol like SDH interfaces, POS interface, ATM data services, GE and other protocols independent of rate as well as Fiber Channel, ESCON and FICON.
  Flexible sub-rate convergence. The system can implement convergence of 2⊙GE, 4⊙155M, 4⊙622M and 4⊙any, improving transport network channel utilization ratio as well as reducing bit operation cost. It can also provide 1+1 path protection.
  Easy scalability with modular design. With the increase of bandwidth, it can realize smooth capacity upgrade on condition that the existing services are not interrupted. Its high maintainability, small size and low power consumption satisfies various requirements of installation environment.

Large commercial applications
ZTE has deployed multiple major optical transmission networks around the world, proving the advanced nature of technologies and equipment reliability.

• West ring of China Mobile: In 2003, China Mobile contracted ZTE as the sole DWDM solution supplier for Phase 1 of its West Ring project covering 17 provinces in Western and Southern China. With the explosive growth of services, China Mobile selected ZTE again to carry out Phase 2 construction Phase 2 is an independent network that will overlap with Phase 1, covering 13 comparatively developed provinces of the same region.
  The network will improve transmission capacity and meet the bandwidth demands of increasing data and multi-media services. The over 10, 000km network features powerful capacity expansion and upgrade capability. It can be upgraded smoothly to 160-wavelength system. Upon completion, the network will be the largest optical transmission network in the world with most nodes and longest transmission distance.
• India BSNL national backbone network: BSNL is the biggest state-owned telecom operator in India. In 2002, ZTE successfully completed the Phase I project of BSNL national backbone network. Owing to its excellent equipments and services, ZTE was authorized to construct the Phase II capacity expansion project. The whole network covers two thirds of the country area of India and is the largest national DWDM backbone transmission network in India.
• Bulgaria Cabletel national backbone transmission network: ZTE is the sole provider of it, the first DWDM transmission network project in Bulgaria in march2005 and won Phase II installation contact in the same year. The whole network reach to 800 kilometre and will connect Romania and Turkey.
• Romanian backbone network: In Sep 2005 ZTE announced it has won the contract to supply Euroweb International, a leading ISP in the Central Eastern European region, with SDH equipment for its optical network in Romania. The deal will provide Euroweb with optical transmission equipment for each of its 14 nodes based in major Romanian cities including Oradea, Arad, Brasov and Buzau.
• Macedonia backbone network: ZTE deployed its first optical transmission network in Macedonia in 2005 with Neocom, the countryˇs second largest data communication operator. The network, due for completion in December 2006, will cover five major cities of the country - Ohrid, Gostivar, Skopje, Stip and Negotino, and connecting Macedonia with surrounding countries Serbia & Motenegro, Kosovo, Albania, Bulgaria and Greece.

According to the latest statistics released by market research company RHK Inc.,  the global market share of ZTEˇs optical network products has grown by 27% over the previous year and is becoming the fastest growing supplier of optical transport equipment in the world. ZTE optical networks have been deployed in approximately 70 countries and regions around the world so far. Its growing importance to the global optical network market is manifested in the active role played by it.