IPoDWDM

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IP over DWDM (IPoDWDM) is a technology used in telecommunications networks to integrate IP routers and network switches in the OTN (Optical Transport Network). A true IPoDWDM solution is implemented only when the IP Routers and Switches support ITU-T G.709. [1] In this way IP devices can monitor the optical path and implement the transport functionality as FEC (Forward Error Correction) specified by ITU-T G.709/Y.1331 [1] or Super FEC functionality defined in ITU-T G.975.1. [2]

Contents

Benefits

This approach saves network components including shelves, processors, interfaces cards and hence it permits to reduce the power consumption, OPEX (Operational expenditure) and CAPEX (capital expenditure). This approach brings also a simplification of the network, eliminating the SDH/SONET intermediate layer. [3]

Multivendors

A DWDM network can be implemented using different vendor technology from the IP devices as long as they support alien wavelength transmission specified by ITU-T G.698.2. [4] [5]

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G.709 ITU-T recommendation

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An optical module is a typically hot-pluggable optical transceiver used in high-bandwidth data communications applications. Optical modules typically have an electrical interface on the side that connects to the inside of the system and an optical interface on the side that connects to the outside world through a fiber optic cable. The form factor and electrical interface are often specified by an interested group using a multi-source agreement (MSA). Optical modules can either plug into a front panel socket or an on-board socket. Sometimes the optical module is replaced by an electrical interface module that implements either an active or passive electrical connection to the outside world. A large industry supports the manufacturing and use of optical modules.

Coherent optical module refers to a typically hot-pluggable coherent optical transceiver that uses coherent modulation and is typically used in high-bandwidth data communications applications. Optical modules typically have an electrical interface on the side that connects to the inside of the system and an optical interface on the side that connects to the outside world through a fiber optic cable. The technical details of coherent optical modules were proprietary for many years, but have recently attracted efforts by multi-source agreement (MSA) groups and a standards development organizations such as the Optical Internetworking Forum. Coherent optical modules can either plug into a front panel socket or an on-board socket. Coherent optical modules form a smaller piece of a much larger optical module industry.

References

  1. 1 2 "Interfaces for Optical Transport Network (OTN)”, ITU-T G.709/Y.1331
  2. "Forward error correction for high bit-rate DWDM submarine systems", ITU-T G.975.1
  3. Virgilio Puglia, Olga Zadedyurina, “optical transport networks: from all-optical to digital”, IEEE,31 August 2009 ISBN   978-92-61-12891-3
  4. D. Ventorini, E. Moura, L. Paraschis, O. Gerstel, M. Silva, K. Wollenweber, A.J. Silverio, P.P. Henrique, L.A.C. Silva "Demonstration and evaluation of IP-over-DWDM networking as "alien-wavelength" over existing carrier DWDM infrastructure", Optical Fiber communication/ National Fiber Optic Engineers Conference, Issue , 24–28 February 2008 Page(s):1 – 6
  5. Amplified multichannel DWDM applications with single channel optical interfaces", ITU-T G.698.2