Review The next generation of passive optical networks: A review Q2 Huda Saleh Abbas n , Mark A. Gregory Q1 RMIT University, Melbourne, Australia article info Article history: Received 8 November 2015 Received in revised form 5 February 2016 Accepted 21 February 2016 Keywords: EPON GPON XG-EPON XG-GPON1 XG-GPON2 TDM-PON WDM-PON TWDM-PON OCDM-PON OFDM-PON Physical layer Data link layer Hybrid technology abstract Passive O Q3 ptical Net Q4 works (PONs) have become a popular fiber access network solution because of its service transparency, cost effectiveness, energy savings, and higher security over other access networks. PON utilizes passive low-power components which removes the need for power-feeding in the fiber distribution network. This paper presents three different generations of PON that are based on the Ethernet PON and Gigabit PON standards. This article showcases the first generation of PON in terms of physical and data link layers and forms the basis for discussion about the different approaches being pursued for the next generation stage 1 PON (NG-PON1). Additionally, the main objective of this study is to review the technologies proposed for the next generation stage 2 PON (NG-PON2); highlighting the important contributions and limitations of the corresponding technologies. Hybrid approaches that combine multiple technologies are introduced as a solution to eliminate major limitations and to improve overall system-wise performance. However, NG-PON2 is still suffering from a number of chal- lenges include cost, reach, capacity and power consumption are discussed at the end of this paper. Another purpose of this paper is to identify potential remedies that can be investigated in the future to improve the performance of the NG-PON2. & 2016 Elsevier Ltd. All rights reserved. Contents 1. Introduction .......................................................................................................... 2 2. Deployed EPON and GPON .............................................................................................. 3 2.1. Physical layer ................................................................................................... 3 2.2. Data link layer .................................................................................................. 4 3. NG-PON 1 ........................................................................................................... 5 3.1. From EPON to XG-EPON .......................................................................................... 5 3.2. From GPON to XG-GPON.......................................................................................... 5 3.3. Mixed scenario.................................................................................................. 6 4. ING-PON2 pure technologies ............................................................................................ 6 4.1. High speed TDM-PON ............................................................................................ 6 4.2. WDM-PON ..................................................................................................... 7 4.3. OCDM-PON .................................................................................................... 8 4.4. OFDM-PON..................................................................................................... 9 4.5. UNI-PON....................................................................................................... 9 4.6. PDM-PON ..................................................................................................... 10 5. ITU-T NG-PON2 technology............................................................................................. 10 5.1. TWDM-PON ................................................................................................... 10 5.2. Point-to-Point WDM Overlay ..................................................................................... 11 6. ITU-T Standards for NG-PON2 ........................................................................................... 11 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/jnca Journal of Network and Computer Applications http://dx.doi.org/10.1016/j.jnca.2016.02.015 1084-8045/& 2016 Elsevier Ltd. All rights reserved. n Corresponding author. E-mail addresses: Huda.s.abbas@gmail.com (H.S. Abbas), mark.gregory@rmit.edu.au (M.A. Gregory). Please cite this article as: Abbas HS, Gregory MA. The next generation of passive optical networks: A review. Journal of Network and Computer Applications (2016), http://dx.doi.org/10.1016/j.jnca.2016.02.015i Journal of Network and Computer Applications ∎ (∎∎∎∎) ∎∎∎–∎∎∎