Intelligent Optical Network Solution Based on iOTN

1. Driving force of intelligent optical network

With the explosive growth of Internet applications, data services and high bandwidth consumption of network upload and download applications, the demand for bandwidth in the backbone network has also increased rapidly, and the advantages of traditional voice services and dedicated line services have been greatly weakened. In addition, with the popularization of IPTV and video terminals, it can be expected that these new services will continue to promote the rapid development of the bandwidth of the service bearer network in the future. Therefore, the traditional optical network (SDH/MSTP and DWDM network) based on ring network will face new challenges in dealing with such rapidly increasing services.

The mature commercial use of single-wavelength 40G technology and the launch of 100G technology, as well as the large-scale commercial use of C-band 96-wavelength systems, will alleviate the high-bandwidth requirements of transmission networks to a certain extent.

The introduction of OTN and WASON technologies enables flexible service scheduling. OTN can achieve flexible service scheduling and multiplexing at the ODU0/1/2/3 level. The application of WASON technology will reduce the complexity of network management and maintenance and improve service configuration capabilities through the use of intelligent software.

2. Intelligent optical network Solution

After nearly 15 years of development, DWDM has continuously increased the number of wavelengths and the capacity of a single wavelength, and ZTE is able to provide 80/96chx40G/100G transmission capacity. In addition, by using high-power amplifiers, Raman amplifiers, and improving the transmission coding format and FEC coding, the transmission distance of the WDM system has been continuously extended. Now ZTE's 10G system supports up to 5000km of non-electrical relay transmission, and the 40G system supports up to 1500km of non-electrical relay transmission. For more information, please log in to the Electronic Fans Network ( www.elecfans.com )

Ultra-long-distance solves the transmission capacity problem of the backbone core network. With the trend of network flattening, WDM not only transmits traditional TDM signals, but also directly carries more and more IP services, VIP dedicated line services and storage data services. The suddenness and flexibility of data services have put forward intelligent functional requirements for WDM networks.

The intelligent next-generation optical network of iOTN needs to have the following functional features:

● Automatic discovery function, automatic discovery of packet topology, services and resources;
● It has the ability to quickly and dynamically establish connections, and can provide protection and recovery functions for the required services;
● It provides complete service protection and recovery capabilities. In the event of a network failure, it supports dynamic wavelength routing planning and allocation, can resist multiple points of network failure, and improve the survivability of services;
● It can provide services of different types and priorities, and refine the QoS type of services;
● It has intelligent network automatic adjustment capabilities, can automatically calculate OSNR, dispersion, PMD according to these changes in the network environment, and automatically adjust amplifiers and channel equalizers according to the physical damage model, while supporting service path optimization and adjustment;
● It has complete computing capabilities, can perform calculations, analysis, reasoning and judgments according to these changes in the network environment, and finally make decisions based on the principle of effective resource allocation.

In order to achieve the above functions, ZTE DWDM system provides a unified iOTN solution platform with optical and electrical cross-connection and L2 layer switching.

■10T optical layer wavelength tuning

The iOTN platform has a multi-dimensional ROADM solution based on direction-independent and wavelength-independent. ZTE can provide a variety of ROADM solutions based on WB/PLC/WSS. Among them, the multi-dimensional ROADM based on WSS technology supports flexible wavelength-level service scheduling capabilities from 2 to 10 dimensions. Service scheduling supports from 8 channels to 96 wavelengths, and the scheduling granularity can support 2.5G, 10G or 40G. The maximum service scheduling capacity is 38.4T. For more information, please log in to the Electronic Fans Network ( http://www.elecfans.com/ )

Figure 1: ZTE DWDM optical and electrical cross-connect service scheduling model

■T-level OTN-based ODUk sub-wavelength scheduling

ZTE DWDM transmission platform provides large-capacity electrical cross-connection ZXONE 8000 series products. This series of products can meet the access of multiple services such as TDM/IP/FC to the greatest extent, support ultra-large capacity service scheduling and ultra-long distance transmission, and provide an intelligent management system platform.

The cross-connect capacity of the electrical cross-connect platform is 800G, 1.6T and 3.2T respectively. Products with different cross-connect capacity are positioned in the core layer of the metropolitan area network and local network, provincial trunk lines or national trunk lines. The cross-connect particles support ODU0/1/2/3.

The cross-platform has the following features:

ODU0 scheduling, tailor-made for GE

•Fully supports ODU0’s overhead and scheduling, truly achieving refined management and low-cost operation of GE services.

• Fine-grained management: ODU0 encapsulates GE, and has end-to-end processing and transmission capabilities for GE services;

• Low-cost operation: GE services use ODU0 scheduling to effectively save wavelengths and reduce equipment board investment.

Large-capacity ODUk electrical cross-connect

•Supports 0.8T/1.6T/3.2T large-capacity electrical layer cross-connection, and can realize multi-granular non-blocking electrical cross-connection such as ODU0/1/2/3; supports overhead and clock transmission of various services, suitable for network aggregation and core nodes, and provides large-capacity cross-connection scheduling function.

High reliability system architecture

•The main control unit, power module unit, and clock unit support redundant 1+1 hot backup;

• The cross-connect unit adopts advanced redundant protection and supports multiple redundant protection. Compared with M+N protection technology, M:N protection greatly improves the safety of the equipment.

Client-side and line-side separation architecture

•Separation of the client side and the line side, business sharing line bandwidth, effectively improving network bandwidth utilization;

• Customer-side boards or line-side boards can be flexibly increased or decreased according to actual needs to protect the operator's investment;

• Customer-side and line-side boards can be flexibly combined to reduce the types of spare parts from M×N to M+N (M and N are the number of customer-side boards and line-side boards respectively; M and N>2), reducing operation and maintenance costs.

Flexible access to multiple services

•Support STM-1/4/16/64/256, POS, GE/10GE/40GE, OTU1/2/3, DVB, ESCON, FC100/200/400/800/1200 and other service access;

•Any-type universal service access board, meeting the operator's needs for mixed transmission of multiple services.
Based on ODUk carrier-grade reliable protection

• Based on our many years of engineering practice and strong technical strength in the field of optical network protection, we have launched a variety of protection methods at the fiber level, wavelength level, sub-wavelength level, and L2 level:

• Fiber level: line 1+1 protection, optical multiplex section 1+1 protection, optical multiplex section shared protection;

• Wavelength level: optical channel sharing protection, optical channel 1+1 protection;

• Sub-wavelength level: ODUk 1+1 protection, ODUk shared protection;

•L2 layer: ESR protection.

High integration, green and energy-saving

• The highest integration in the industry, a single board can access 8-way 10G or 16-way GE/2.5G services, and a single subrack supports 800G/1.6T/3.2T cross-capacity, effectively saving equipment room area;

The industry's lowest power consumption helps operators build green and energy-saving networks (see product specifications for specific power consumption indicators).

■Flexible L2 packet switching capability

ZTE DWDM transmission platform integrates L2 switching technology, which can well support Ethernet services, with a switching capacity of 40G. In order to better transmit Ethernet services, it can provide transparent transmission for data and support static multi-routing technology to transmit Ethernet services. The former uses TDM technology to transparently transmit Ethernet services; the latter uses L2 switching technology to improve the transmission efficiency of Ethernet services.

It can realize the bandwidth aggregation and convergence function of 24 GE + 2 10GE to 10GE, service QoS management and QinQ, etc. L2 technology can provide rigid and flexible transmission pipelines for packet services, effectively improve the carrying efficiency, and provide different QoS carrying services for different services.

In addition, the system supports L2-based ESR Ethernet ring network protection ZESR, which supports LOS and B1 error detection. The protection switching time fully meets the standard requirement of less than 50ms. After the protection switching occurs, the working status can be queried on the network management. The consistency of all protection switching test data is good, and the system has excellent stable performance during the switching work.

■ Comprehensive software solutions

ZTE provides unified intelligent management and intelligent control solutions for OTN network intelligent control:

●Firstly, in terms of network design and planning technology, it provides an industry-leading network service planning platform: the platform has the following functions:

◆WDM network phased planning, network expansion incremental planning, capital investment budget planning, and different network architectures, topologies and technical feasibility analysis, network solution output;

◆Service wavelength routing allocation, network parameter setting and automatic calculation, site type selection, configuration of equipment boards and modules at each site

◆Network indicator evaluation, solution resource statistics, network optimization suggestions

◆WASON service protection and recovery settings, service path protection and recovery calculations, fiber and site failure dynamic simulation, simulation statistics report output, etc.

●Secondly, the transmission network planning software can realize the intelligent configuration of the OTN network and has a user-friendly intelligent management interface. Its configuration, alarm, performance, security, and audit interfaces are fully upgraded to meet the needs of intelligent control;

●Finally, ZTE's new generation of iOTN equipment fully realizes the loading of the control plane, realizes the dynamic update of network topology and resources, and automatic discovery; service path protection + intelligent recovery automatic calculation, automatic deployment; supports SPC, and can realize the rapid configuration function of services. For more information, please log in to the Electronic Fans Network ( http://www.elecfans.com/ )

Figure 2: ZTE transmission network intelligent management and control unified solution