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Novel rogue optical network unit detection algorithm for gigabit passive optical networks

Horvath T., Munster P., Dubravec L., Filka M.

Optica Applicata

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2016

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Vol. 46, nr 3

421--433

EN

Passive optical networks are widely used as a promising solution for future access networks. Currently, the bandwidth is still increasing which means the current copper networks are not able to transfer new services such as 4K video, live streaming, etc. In other words, they reached their capacity limit. The passive optical networks rely on point-to-multipoint technology. That means each customer uses a share medium by time slots. Each time slot exactly specifies who and when is able to transfer data. In general, this control mechanism is implemented in the optical network unit by worst transmission convergence layer. On the other hand, there are cases when the optical network unit (it is called rogue optical network unit) does not follow instructions provided by the optical line termination, for example, if an attacker modifies a firmware of the end unit and/or when the control protocol is not loaded properly inside optical network unit. In worst case, the optical network unit transmits data in a continual mode (other optical network units cannot send data). Thestandard defines finding of the rogue optical network unit but it does not specify how the rogue optical network unit should be allocated because the frames of the rogue optical network unit do not contain the proper parameters. We realized a measurement in a real network with the rogue optical network unit and then we analyzed the captured data. A new algorithm for the rogue optical network unit allocation is presented. We do not consider any modification of the transmission convergence layer in gigabit passive optical networks.

2

GPON, the Ultimate Pertinent of Next Generation Triple-play Bandwidth Resolution

Sultan D. M. S., Arefin Md. T.

Journal of Telecommunications and Information Technology

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2011

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nr 2

53-60

EN

Optical transmission is getting more popular in the access network due to the increasing demand for bandwidth. New services like IP television (IPTV) transmission, video on demand (VoD) etc. over Internet together along high speed Internet access are confronting the demand of higher bandwidth at the customer end in today's Ethernet network backbone. Even though today's well deployed XDSL (i.e., VDSL/VDSL2+, SHDSL) solutions can satisfy bandwidth demand but are limited to the restriction regarding distance. Hereby, the suitable solution for high bandwidth demand with a long reach can be met by reaching optical cable to cus- tomer end directly. One of the possible ways would be to install passive optical network (PON). Gigabit PON (GPON) is the far-most advanced PON solution used by European and US providers while providers in Asia predominantly use EPON/GePON. This GPON is the basic technology to support the structure of the next-generation fiber to the home (FTTH) system. This paper provides an overview of such GPON solution associating its network architecture, transmission mechanisms and some key services.

3

Przykład konfiguracji szerokopasmowej sieci dostępowej ANS

Rudnicki M.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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1998

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nr 12

848-853

PL

Omówiono budowę światłowodowej sieci dostępowej ANS BOSCH TELECOM z wykorzystaniem światłowodu w łączu abonenckim FITL. Zamieszczono opis modułów wchodzących w skład multipleksera MSV5, krotnicy MS1/4, elestycznego multipleksera XMP1 i jednostek optycznych ONU, które są integralnymi częściami systemu ANS.

EN

ANS Bosch Telecom fiber optic access network with using the fiber network in FITL subscriber loop has been described. Description of midules of MSV5 and MS1/4 Modular SDH Multiplexers and Optical Network Unit ONU which constitute parts of ANS system are placed.