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Odporność sieci xPON nadziałanie nieposłusznej jednostki ONU

Kula Sławomir, Kowalska Weronika

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2023

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nr 4

252--255

PL

Referat jest poświęcony problemowi zakłócania lub uniemożliwiania transmisji w górę w sieciach dostępowych xPON w wyniku niewłaściwego działania jednostki ONU, tak zwanej jednostki rogue ONU wchodzącej w skład sieci xPON. W tym celu przeprowadzono badania laboratoryjne sieci GPON, zastępując jedną z jednostek ONU przestrajanym nadajnikiem laserowym. Uzyskane wnioski rozciągnięto na systemy XG-PON i NG-PON.

EN

The paper is devoted to the problem of interfering or preventing upstream transmission in xPON access networks as a result improper operation of the ONU, the socalled rogue ONU included in the xPON network. For this purpose laboratory tests of GPON network were carried out, replacing one of the ONUs with a tunable laser transmitter. The obtained conclusions were extended to XG-PON and NG-PON networks.

2

Deep data analysis in gigabit passive optical networks

Horvath T., Krkos R., Dubravec L.

Optica Applicata

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2017

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Vol. 47, nr 1

157--170

EN

This paper focuses on practical aspects of gigabit passive optical networks (GPON) diagnostics during deployment, for root-cause analysis and for research purposes. While GPON signalling analysis is already quite commonly used for diagnostics, the aim of this work is a holistic approach, including both signalling and user plane (payload) analysis. User plane analysis, especially if targeted at payload Ethernet, IP and transport layers, enables detection of additional group of problems that could limit or even prevent GPON internetworking and thus degrade the user perceived service quality. Integrated signalling and payload analysis is also interesting from the research point of view, leading to the ability to study equipment idiosyncrasies that would be hard to detect otherwise and it is also one of the enablers of equipment security verification. The mentioned theories were tested during a practical diagnostic session on a real GPON network deployment and this paper presents the findings.

3

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.

4

FTTB+LAN : a flexible access architecture for residential and business users

Parol P., Pawłowski M.

Przegląd Teleinformatyczny

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2013

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T. 1, Nr 1 (19)

3-27

EN

In this study we propose an approach of building a modern high-speed access network based on FTTB+LAN architecture in multi-dwelling buildings where cat.5 copper infrastructure is available and can be used. Presented approach allows building easy-to-implement and cost-effective access solution which can be deployed for both residential and business users. The study provides a wide view on network architecture design and presents methods of how to carry user traffic in effective way within the considered architecture. Thanks to a flexible approach various service profiles cohabitation in one access network is feasible.

PL

Przedstawiono propozycje podejścia do budowy nowoczesnego, szerokopasmowego punktu dostępowego sieci, bazującego technologii FTTB+LAN, w budynkach wielorodzinnych, w których dostępne jest okablowanie miedziane kategorii 5. Prezentowane podejście pozwala na budowę niedrogich rozwiązań, które łatwo mogą być wdrażane dla użytkowników indywidualnych i biznesowych. W niniejszym opracowaniu szeroko omówiono architektury sieci dostępowych, wraz ze sposobem efektywnego przekazywania ruchu użytkowego. Przedstawiona elastyczna architektura dostępowa umożliwia wykorzystanie jednej sieci dostępowej dla różnych profili usług.