Performance study of packet-optical transport network protocols

Abstract

This research is carried out in the field of Optical Transport Network (OTN), in particular, to investigate the performance of a new protocol called Packet Optical Network that was introduced as a successor to the legacy Synchronous Digital Hierarchy/Synchronous optical networking (SDH/SONET). The migration to IP/Ethernet application globally is forcing enterprises to address two major (Wide Area Network) WAN issues: converging Time Division Multiplexing (TDM) and packet networks to reduce expenses, and improving network and service management to support delay-sensitive, bandwidth-intensive applications. Optical Transport Network - ITU G.709 is a global standard to address these challenges by eliminating unnecessary layer, IP straight over optic without being encapsulated in ATM/SDH frames, and eventually reduce Optical-Electronic-Optical (OEO) conversion. The International Telecommunication Union Telecommunication Standardization Sector ITU-T defines an OTN as a set of Optical Network Elements (ONE) connected by optical fiber links, able to provide functionality of transport, multiplexing, switching, management, supervision, and survivability of optical channels carrying client signals. Packet Optical Network or often called Optical Channel Digital Wrapper added more functionalities to the legacy SONET/SDH such as the inclusion of stronger FEC, switching scalability, Transparency, and different frame rates. The Optical Channel Payload Envelope (OCh PE) can carry any type of data: SONET/SDH, GbE, 10GbE, ATM, IP, and so on. The objective of this research is to model an Optical Transport Network in the OMNeT++ simulation environment and OptiSystem Software, where the performance of Packet Optical Network protocols is compared with the legacy system in terms of delay and error correction capability. Simulation conducted in the metro/core optical network environment shows that the optical network performances in delay and error performance are improved when using the Packet optical network protocol, up to 30% decrease in delay can be achieved and longer distances can be reached by employing the new more powerful Forward Error Correction of the Digital Wrapper G.709.