Vloga OTN distribuiranih prevezovalnikov v regionalnih komunikacijskih omrežjih

The role of OTN distributed cross-connects in regional communication networks


Klaus Samardžić
SmartCom


POVZETEK - Prvotni protokoli za optična transportna omrežja G.798 "Characteristics of Optical Transport Network hierarchy equipment functional blocks" so bili definirani na začetku tega stoletja in so imeli vidno vlogo pri arhitekturah sodobnih transportnih omrežjih, v katerih se uporablja valovno multipleksiranje optičnih signalov – WDM (Wavelength Division Multiplexing). Pri tem je bila osrednja arhitektura transportnih omrežij optično procesiranje signalov in ROADM (Reconfigurable Optical Add Drop Multiplexer). Možnosti uporabe OTN prevezovalnikov elektronskih signalov so bile omejene. Linijski signal z nekoherentnim načinom prenosa je bil omejen na hitrost 10 Gbit/s in ni omogočal smiselnih OTN gradbenih elementov za izvedbo prilagodljivega transportnega omrežja. Z vpeljavo linijskih signalov s koherentnim načinom prenosa in hitrostmi 400 Gbit/s in 800 Gbit/s je bilo omogočeno prenašanje uporabniških signalov s hitrostmi od 1 Gbit/s do 400 Gbit/s. Protokoli za OTN-omrežja so danes prilagojeni za učinkovit prenos signalov različnih oblik, kot so Ethernet, Fibre Channel in Common Public Radio Interface (CPRI). Implementacija agregacije, multipleksiranja in prevezovanja elektronskih signalov v OTN-arhitekturah omogoča graditev učinkovitih in prilagodljivih omrežij. Prispevek obravnava gradbene elemente in poda zgled možne arhitekture regionalnega omrežja v Sloveniji, z uporabo OTN-distribuiranih prevezovalnikov.

ABSTRACT - Optical transport networks protocols described in G.798 "Characteristics of Optical Transport Network hierarchy equipment functional blocks" were defined at the beginning of this century and played a prominent role in the architectures of modern transport networks in which wave multiplexing of optical signals - WDM (Wavelength Division Multiplexing) is used. Architectures of transport networks were based on optical signal processing and ROADM (Reconfigurable Optical Add Drop Multiplexer). Possibilities of using OTN cross-connects for electronic signals processing were limited. The line signal using a non-coherent transmission mode was limited to a speed of 10 Gbit/s and did not allow meaningful OTN building blocks for the implementation of flexible transport networks. By introducing line signals using a coherent transmission mode and speeds of 400 Gbit/s and 800 Gbit/s, it is possible to transmit user signals from 1 Gbit/s to 400 Gbit/s. Protocols for OTN networks today are adapted to efficiently transmit signals of various formats, such as Ethernet, Fiber Channel and Common Public Radio Interface (CPRI). The implementation of aggregation, multiplexing and cross-connection of electronic signals in OTN-architectures enables the implementation of efficient and flexible networks. The paper discusses the building elements and gives an example of a possible architecture of a regional network in Slovenia, using OTN-distributed cross-connects.