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The next generation passive optical networks (NG-GPON) such as long reach GPON is the future-proof solution to answer the continuous demands for access user bandwidth and network expansion. However, security which is yet to be addressed in NG-GPON needs urgent attention as it will become more critical due to much longer distance, denser user population and more network elements. In addition, the longer propagation delay in NG-GPON can also lead to a more complex bandwidth allocation mechanism that is expected to operate in a dynamic manner. Among the highlights of recommendations for future implementation are improvements in the security aspect and the use of dynamic bandwidth allocation (DBA) algorithm that suit the characteristics of long reach GPON. Current PON is exposed to degradation attack, a security breach that can harm how bandwidth fairness mechanism among ONUs work. Thus, this project proposes a secured DBA mechanism for NG-PON that could overcome this particular threat. In specific, a detection phase will be included in the DBA mechanism to sense and subsequently mitigate abnormal behaviours among ONUs that are harmful to the goal of DBA i.e. to ensure QoS among ONUs and traffics. At the same time, careful attention is given on the delay parameter as it is a critical parameter that can affect DBA performance in long reach GPON. In this paper, preliminary analysis is shown that reveal how possibility of threats increase with increasing of distance and network elements.

The next generation passive optical networks (NG-GPON) such as long reach GPON is the future-proof solution to answer the continuous demands for access user bandwidth and network expansion. However, security which is yet to be addressed in NG-GPON needs urgent attention as it will become more critical due to much longer distance, denser user population and more network elements. In addition, the longer propagation delay in NG-GPON can also lead to a more complex bandwidth allocation mechanism that is expected to operate in a dynamic manner. Among the highlights of recommendations for future implementation are improvements in the security aspect and the use of dynamic bandwidth allocation (DBA) algorithm that suit the characteristics of long reach GPON. Current PON is exposed to degradation attack, a security breach that can harm how bandwidth fairness mechanism among ONUs work. Thus, this project proposes a secured DBA mechanism for NG-PON that could overcome this particular threat. In specific, a detection phase will be included in the DBA mechanism to sense and subsequently mitigate abnormal behaviours among ONUs that are harmful to the goal of DBA i.e. to ensure QoS among ONUs and traffics. At the same time, careful attention is given on the delay parameter as it is a critical parameter that can affect DBA performance in long reach GPON. In this paper, preliminary analysis is shown that reveal how possibility of threats increase with increasing of distance and network elements.

This document defines a portion of the Management Information Base (MIB) for use with network management protocols in TCP/IP based Internets. In particular, it defines objects for managing interfaces that conform to the Ethernet Passive Optical Networks (EPON) standard as defined in the IEEE Std 802.3ah-2004, which are extended capabilities to the Ethernet like interfaces. [STANDARDS-TRACK]

We present an application focused on the design of resilient long-reach passive optical networks. We specifically consider dual-parented networks whereby each customer must be connected to two metro sites via local exchange sites. An important property of such a placement is resilience to single metro node failure. The objective of the application is to determine the optimal position of a set of metro nodes such that the total optical fibre length is minimized. We prove that this problem is NP-Complete. We present two alternative combinatorial optimisation approaches to finding an optimal metro node placement using: a mixed integer linear programming (MIP) formulation of the problem; and, a hybrid approach that uses clustering as a preprocessing step. We consider a detailed case-study based on a network for Ireland. The hybrid approach scales well and finds solutions that are close to optimal, with a runtime that is two orders-of-magnitude better than the MIP model.

It is shown that a POPS network with g groups and d processors per group can efficiently route any permutation among the n=dg processors. The number of slots used is optimal in the worst case, and is at most the double of the optimum for all permutations p such that p(i) i for all i.

It is shown that a POPS network with g groups and d processors per group can efficiently route any permutation among the n=dg processors. The number of slots used is optimal in the worst case, and is at most the double of the optimum for all permutations p such that p(i) i for all i.

Environmental concerns have motivated network designers to further reduce energy consumption of access networks. This paper focuses on reducing energy consumption of Ethernet passive optical network (EPON) as one of the most efficient transmission technologies for broadband access. In EPON, the downstream traffic is sent from the optical line terminal (OLT) located at the central office to all optical network units (ONUs). Each ONU checks all arrival downstream packets and selects the downstream packets destined to itself. Therefore, receivers at ONUs have to always stay awake, thus consuming a large amount of energy. Contrariwise, an ONU transmitter can be triggered by the arrival of the upstream traffic and so it can go to the low power mode when no traffic is observed. Putting ONUs into the low power mode during light traffic is a known strategy for energy saving. In this article, we address the downstream challenge and also improve the ONU transmitter sleep time by proposing a simple sleep control scheme. We also propose an upstream and a downstream sleep-aware traffic scheduling scheme to avoid missing the packets during the sleep states. The proposed sleep control scheme does not need the handshake process and is based on the mutual inference at OLT and ONU. Simulation results show that the proposed scheme can save energy as much as 60% when the network traffic is light.

This paper establishes the state of the art in both deterministic and randomized online permutation routing in the POPS network. Indeed, we show that any permutation can be routed online on a POPS network either with $O(\frac{d}{g}\log g)$ deterministic slots, or, with high probability, with $5c\lceil d/g\rceil+o(d/g)+O(\log\log g)$ randomized slots, where constant $c=\exp (1+e^{-1})\approx 3.927$. When $d=\Theta(g)$, that we claim to be the "interesting" case, the randomized algorithm is exponentially faster than any other algorithm in the literature, both deterministic and randomized ones. This is true in practice as well. Indeed, experiments show that it outperforms its rivals even starting from as small a network as a POPS(2,2), and the gap grows exponentially with the size of the network. We can also show that, under proper hypothesis, no deterministic algorithm can asymptotically match its performance.

As passive optical networks (PON) are increasingly deployed to provide high speed Internet access, it is important to understand their fundamental traffic capacity limits. The paper discusses performance models applicable to wavelength division multiplexing (WDM) EPONs and GPONs under the assumption that users access the fibre via optical network units equipped with tunable transmitters. The considered stochastic models are based on multiserver polling systems for which explicit analytical results are not known. A large system asymptotic, mean-field approximation, is used to derive closed form solutions of these complex systems. Convergence of the mean field dynamics is proved in the case of a simple network configuration. Simulation results show that, for a realistic sized PON, the mean field approximation is accurate.

We propose a scheme for quantum key distribution (QKD) in a passive optical network (PON) based on differential phase shift (DPS) coding. A centralized station including all expensive components serves many users, making it suitable for a true multi-user network in a local environment with moderate distances on the order of a few kilometers. The emphasis lies on an asymmetric design for cost effective implementation of network end points.

In this paper, the parameters of optical amplifiers are evaluated using numerical methods with the Optisystem software. The main objective of this evaluation is the implementation of an optical telecommunication architecture, able to push back the current limits, due to a more and more restricted bandwidth following a demand which does not stop growing. We start from a study of the classical architecture of an optical telecommunication network with an external modulation provided by the mach zehnder modulator, the non return to zero (NRZ) coding, a pseudo random bit generator and a continuous wave (CW) laser diode of frequency 193.1 THz. The results obtained show a transmission possibility at 30.8 dBm and an output power of 25 dBm (316 mW) with an electrical rate signal to noise (SNR) and optical rate signal to noise (OSNR) beyond 34 dBm. The successive integration of the different amplifiers will improve these results with a gain of more than 10 dBm and also provide a better signal quality.

This paper proposes a novel scheme which can efficiently reduce the energy consumption of Optical Line Terminals (OLTs) in Time Division Multiplexing (TDM) Passive Optical Networks (PONs) such as EPON and GPON. Currently, OLTs consume a significant amount of energy in PON, which is one of the major FTTx technologies. To be environmentally friendly, it is desirable to reduce energy consumption of OLT as much as possible; such requirement becomes even more urgent as OLT keeps increasing its provisioning data rate, and higher data rate provisioning usually implies higher energy consumption. In this paper, we propose a novel energy-efficient OLT structure which guarantees services of end users with the smallest number of power-on OLT line cards. More specifically, we adapt the number of power-on OLT line cards to the real-time incoming traffic. Also, in order to avoid service disruption resulted by powering off OLT line cards, proper optical switches are equipped in OLT to dynamically configure the communications between OLT line cards and ONUs.

5G is altering the communications future. The 5G literature focuses on wireless and radio technology, but fiber optics play a crucial supporting role in signal transmission to and from the next generation of base stations (BSs) that will serve customers. With the increasing bandwidth requirements of 5G ultra-high-speed applications, passive optical networks (PONs) are the optimal solution. Targeting long-reach 5G PONs, an integrated, high-speed, and cost-effective optical transmitter circuit was constructed and tested. This engine can be combined into a 5G-compliant optical transceiver module. For the purpose of validating the engine performance, a theoretical analysis and an OptiSim TM -based design simulation model are carried out. Bit error rate (BER), phase-shifting, and eye diagram were all taken into account when analyzing the transmitter performance. The article findings validate the optical transmitter design. The design is cost-effective and requires no extra components, such as a filter.

This document describes the application of MPLS multi-segment pseudowires (MS-PWs) in a dual-technology environment comprising a Passive Optical Network (PON) and an MPLS Packet Switched Network (PSN).

Achievement of transmission (full duplex) over single fiber is a challenge for researchers for Wavelength Division Multiplexed Passive Optical Networks. There are many schemes available but they suffer from transmission issues because of using transmissions on the same wavelength with bidirectional transmissions. This results in the reduction of transmission distances between optical fiber terminal equipment and the optical network units. This happens because Rayleigh’ backscattering noise and there is a need to reduce that noise substantially. In this research work channels capacity Dense Wavelength Division Multiplexing (DWDM), Passive Optical Networks (PON) are simulated after extensive testing. The main aim is enhancing the capacity over a distance with less bit error rates. This was achieved through the design optimization using Rayleigh’ Backscattering elimination technique thus enhancing the performance.

The purpose of this document is to provide applicability of the Access Node Control Mechanism to broadband access based on Passive Optical Networks (PONs). The need for an Access Node Control Mechanism between a Network Access Server (NAS) and an Access Node Complex, composed of a combination of Optical Line Termination (OLT) and Optical Network Termination (ONT) elements, is described in a multi-service reference architecture in order to perform QoS-related, service-related, and subscriber-related operations. The Access Node Control Mechanism is also extended for interaction between components of the Access Node Complex (OLT and ONT). The Access Node Control Mechanism will ensure that the transmission of information between the NAS and Access Node Complex (ANX) and between the OLT and ONT within an ANX does not need to go through distinct element managers but rather uses direct device-to-device communication and stays on net. This allows for performing access-link-related operations within those network elements to meet performance objectives.