ITU-T Kaleidoscope 2009 Innovations for Digital Inclusion OPTICAL TRANSPORT NETWORKS: FROM ALL-OPTICAL TO DIGITAL Virgilio Puglia virgilio.puglia@tin.it Olga Zadedyurina olga.zadedyurina@disi.unitn.it Mar del Plata, Argentina, 31 Aug – 1 Sep 2009

Traditional DWDM based on OTN (Optical Transport Network) ITU-T G.872; Outlines Traditional DWDM based on OTN (Optical Transport Network) ITU-T G.872; IPoDWDM; ODN (Optical Digital Network); Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

IP traffic today becomes dominant: Introduction IP traffic today becomes dominant: New application based on IP (video communication, P2P, etc.); Old application migrate to IP (ex. SS7); IP traffic has overcome capacity of currently used wavelength 10Gb/s; Today trend/evolution is: Eliminate SDH/SONET layer; Move Transport from Optical to Digital; Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Traditional DWDM as an OTN DWDM is a fully optical network which provides transparency: only 1R regeneration (optical amplification-equalization and CD compensation); theoretically the signal can be delivered from every ONE to any other. Traditional (OTN) approach becomes hardly realizable for big network; Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Insert IP traffic into DWDM without mapping into SDH frame; IPoDWDM Approach Insert IP traffic into DWDM without mapping into SDH frame; Integration of DWDM transponders directly into IP switch/router. Transponder G.709 IP routers OTN IPoDWDM G.709 Transponder IP routers Colored interface Transponder MUX Transponder Gray interface Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

IPoDWDM intelligence Preemptive traffic protection becomes possible OTN Working path Lost data Protection p. Work path Protection path BER BER Corrected bits Optical Impaiments FEC Limit POS on router LOF IP Layer IP Layer + G.709 on router FEC Limit SDH/DWDM Layer Corrected bits Transponder Switch threshold Optical Impaiments Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Optical Digital Network Approach The philosophy of ODN is based on O-E-O conversion whenever it is possible. OTN manipulate analogical wavelengths; ODN manipulate digital “bits”. Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Network Layers: OTN vs ODN OTM0 Physical Section (OPSO) Optical Transmission Section(OTS) Optical Multiplex Section (OMS) Optical Channel (OCh) Optical Channel Transport Unit (OTU) Optical Channel Data Unit (ODU) Optical Channel Payload Unit (OPU) IP ATM Ethernet STM-N Digital Analog (not colored, no OSC) OTM0 Physical Section (OPSO) Optical Transmission Section (OTS) Band Multiplex Section (BMS) Optical Digital Channel (ODCh) Optical Channel Transport Unit (OTU) Optical Channel Data Unit (ODU) Optical Channel Payload Unit (OPU) IP ATM Ethernet STM-N Digital Analog (not colored, no OSC) Optical Transport Module (OTM-n, n>1) Optical Transport Module (OTM-n, n>1) Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Each OADM site implements 3R regeneration: ODN advantages Each OADM site implements 3R regeneration: the signal is cleaned up from noise and others distortion; It becomes possible to implement higher number of Channels -160 (C band, spacing 25 GHz); The network lose transparency. Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

ODADM Description Optical pass-through MBM FEC Digital W. DSP FEC East Line West Line O-E O-E O-E O-E O-E O-E Optical Spliter O-E Matrix Matrix O-E Optical Spliter O-E O-E O-E O-E O-E O-E Electrical connection Optical connection To interface modules To interface modules Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion Specific Interface Module

RECONCILATION BETWEEN THE APPROACHES To integrate different approach the existing OTN network must support Alien Wavelets (ITU-T G.698.2) IPoDWDM is easy to integrate into OTN; IPoDWDM is easy to integrate into ODN but not efficiently; ODN can be integrate into OTN using an optical band split filter. Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Example of ODN-OTN integration The majority of deployed DWDM networks are equipped with 100GHz lambda spacing while transponders have stability for 50GHz spacing. Even frequencies 100 Ghz East Line 50Ghz-100Ghz Filter C-Band ODADM C-Band ROADM 192.3 192.5 192 192.1 192.2 192.4 192.6 West Line 100 Ghz 192.05 192.15 192.25 192.35 192.45 192.55 192.65 192.75 Odd frequencies Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Capacity Evolution New capacities are being studied by IEEE 802.3ba 10 Gb/s -> 40 Gb/s -> 100 Gb/s - CD increases and PMD appears; ODN and IPoDWDM: - the limit of 160 channels (L+C band) ODN: - due to E-O-E no dispersion problems. - granularity of PIC is inflexible parameter (today either 10 or 40 Gb/s based) New capacities are being studied by IEEE 802.3ba G.698.2 should standardize new interfaces Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

OTN, IPoDWDM, ODN approaches analyzed; Conclusions OTN, IPoDWDM, ODN approaches analyzed; IPoDWDM and ODN are seen as very promissing; Examples on integration of both technologies; Stimulus for further research and standardization activities; Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

Back up The following slide are for back up

OTN Network Elements OLT (Optical Line Terminal) OTS OMS Och (not terminated in OADM site) Client (not terminated in OADM site) OLT OADM OLA OLT (Optical Line Terminal) OADM/ROADM (Optical Add Drop Multiplexer) also Reconfigurable OLA (Optical Line Amplifier) OXC (Optical Cross-Connect) Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

IPoDWDM Network Elements OTS OMS DWDM MUX/DMUX Optical fibre Optical Line Amplifier Optical colored interface Client-OCh-OTU-ODU-OPU (yellow & green lambda) OCh - Optical Channel OMS - Optical Multiplex Section ONE - Optical Network Element OTS - Optical Transmission Section OTU - Optical Channel Transport Unit ODU - Optical Channel Data Unit OPU - Optical Channel Payload Unit G.698.2 “black-link” IP Router Client-OCh-OTU-ODU-OPU (red & blue lambda) Client-OCh-OTU-ODU- OPU(red & blue lambda) Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion

ODN Network Elements Client OPU ODU OTU OTU ODCh ODCh BMS BMS OTS OTS DNE DNE DNE OPU - Optical Channel Payload Unit Electrical connection ODU - Optical Channel Data Unit Optical connection OTU - Optical Channel Transport Unit DNE - Digital Network Element OLA (Optical Line Amplifier) ODCh - Optical Channel BMS - Band Multiplex Section MBM (Multiplexing Band Module) OTS - Optical Transmission Section Mar del Plata, Argentina, 31 Aug – 1 Sep 2009 ITU-T Kaleidoscope 2009 – Innovations for Digital Inclusion