The Analysis of Network Scale and Reliability in Ring-and-Tree-Based Metro-Access Network with LAN Service

Gan

et al. 2018

Int J Communication

Self Cite

In this paper, a reliable scheme based on star topology is proposed by introducing group protection. Depending on interconnecting fibers, all optical network units (ONUs) are divided into some groups and each group contains 2 ONUs.Through these groups, the network can not only realize efficient transmission of local area network service between adjacent ONUs but also provide mutual protection for ONUs in a group when distribution fibers happen to faults. By using the backup pathway, the network can further provide protections for feeder fibers when they fall in faults. With the help of the optical tunable receiver in ONU, dynamic bandwidth allocation algorithm is also supported to realize flexible bandwidth allocation in 1 group. By the subtly design, the network can realize passivity (there are no active devices in remote nodes), modularization, and scalability. By utilizing amplitude modulation, differential phase shift keying modulation and reflective semiconductor optical amplifier technology, wavelength triple reuse is also achieved. Finally, the results of simulation and performance analysis demonstrate the feasibility of the architecture.KEYWORDS group protection, high reliability, LAN, metro-access network, modularization | INTRODUCTIONWith the rapid development of real-time services, such as teleconference, telemedicine, and online education, the more efficient way of communication needs to be considered, especially for the future optical network. 1 However, direct communication among optical network units (ONUs) is not supported in the traditional optical networks. The communication information needs to be firstly transmitted to the optical line terminal (OLT) and then transmitted to the destination ONUs. This will cause some problems, for example, raising the burden of OLT and even resulting in the information congestions, taking up the bandwidth of up and downstream signals, increasing transmission delay, and so on. To solve these problems, the solutions supporting direct communications among ONUs have been proposed. 2 Meanwhile, optical metro-access network can integrate traditional metro and access layers into metro-access layer, which will meet the flattening development trend of future optical network. 3 In a short, it is becoming increasingly important to support direct communication among ONUs for metro-access network.In the support of services, the schemes supporting local area network (LAN) service can be classified into 5 categories in general: additional transceiver, utilizing upstream signals, broadcasting, virtual ring, and ONU ring. Garg et al transmit and receive LAN service together with downstream and upstream services by placing a transceiver in OLT or remote node (RN). 4 The LAN signals will be transmitted to OLT or RN from initiative ONU and next to destination ONU. Wu et al transmit LAN service through orthogonal modulation technology. 5 By utilizing the light source of upstream signals, the LAN signals are produced. Garg et al broadcast the LAN signals to all output ports of a 8 ×...

Section: Performance Comparisonsmentioning

confidence: 99%

“…

…”

mentioning

confidence: 99%

See 1 more Smart Citation

Group protection and LAN service scheme utilizing flexible modularization and high efficiency for metro‐access network

Gan

et al. 2018

Int J Communication

Self Cite

“…Therefore, the flexibility and efficiency of direct communication is reduced. In our latest research result, the flexibility and efficiency is still not advanced [23]. In addition, it can only support the direct communication among ONUs connected with same RN.…”

Section: Introductionmentioning

confidence: 97%

Dual-Fiber-Ring Architecture Supporting Discretionary Peer-to-Peer Intra-Communication and Bidirectional Inter-communication in Metro-Access Network

Gan

et al. 2019

IEEE Access

Self Cite

Direct communication among optical network units (ONUs) is very significant for next-generation optical networks. In this paper, a metro-access optical network architecture supporting intra-communication and inter-communication is proposed based on dual-fiber ring topology. By adopting two tunable fiber Bragg gratings and one arrayed waveguide grating in the remote node, direct peer-to-peer communication of ONUs can be achieved. By designing the architecture to provide inter-communication in two opposite transmission directions, not only the efficiency and flexibility of inter-communication can be guaranteed depending on the shortest transmission path, but also the inter-communication can be supported even if a dual-fiber fault occurs. By allocating three wavelengths to one ONU, not only the intra-communication and inter-communication for one ONU can be carried out simultaneously, but also the inter-communication for different ONUs can be realized simultaneously. By using a dual-fiber ring structure, both the scale and the reliability can be improved. Because the network capacity and scale are relatively large, the relative construction-and-maintenance cost of the network is low. The availability of the proposal can be verified via the performance analyses and the simulations.

“…In this scheme, the communication signals of ONUs get through all ONUs orderly along the real ONU ring. Li et al use ONU ring to realize direct communication of ONUs and DF protection, simultaneously …”

Section: Introductionmentioning

confidence: 99%

High‐reliability grid architecture supporting discretionary and efficient communication between ONUs in metro‐access optical network

Shao

Zhao

et al. 2019

Int J Communication

Self Cite

Direct communication of optical network units (ONUs) is an important function in metro-access optical network. In this paper, a grid architecture supporting discretionary and efficient communication between ONUs is proposed. The grid architecture is built by using two interconnecting fibers to connect every two ONUs; this can give protection to every ONU by four ONUs.Additionally, the network reliability can be improved greatly. Grid topology of ONUs leads to their discretionary direct communication. In this topology, direct communication signal can be transmitted from one ONU to another ONU directly, rather than being returned to remote node central office. Also, the efficiency of direct communication can be improved remarkably with the proposed architecture. Finally, the performance analyses and the simulation results verify the feasibility of the proposed architecture. When the n reaches to 10, the reliability of downstream and direct communication signals is all larger than 99.993%.