A smarter DWDM/OTN layer in your network Alien waves, packet aggregation and router bypass Guy Roberts Transport Network Architect, GÉANT Technology Exchange, Cleveland 7 th October 2015
Contents Alien waves Alien wave background Economic case for alien waves Field trial results Alien wave production services OTN Router bypass and packet aggregation 2
Alien Waves Theory and economics
Alien wave over DWDM Scaling Fiber Capacity Transmitters Tx Combining and separating colors Amplifier Receivers Rx Optical fiber Tx Rx Tx Demarcation between provider and user Alien Wave provider fibre, amplifiers and muxing Rx Alien Wave user Tx and Rx transponders The AW provider is selling spectrum on their DWDM transmission system DWDM uses the 1525 1565 nm C band to make use of erbium doped fibre amplifiers (EDFAs) Approx. 80 waves per fibre on 50GHz ITU-T grid
The economics traditional transmission services Cost structure for transmission layer: Fixed one-off costs system design costs, installation fees Fixed annualized costs common equipment depreciation, fibre lease, equipment maintenance fee, power etc. Variable costs transponders added on a per-service basis. For the first few services added, the fixed costs greatly exceeds the variable costs. As new services are added the fixed costs per service falls. The break-even point occurs when revenues exceed the overall cost of running the service 5
Economics of alien waves Alien waves allow multiple providers to share one common fibre infrastructure This means that there will be more services on the fibre, and the fixed cost are shared across many services, reducing the overall cost. The collaboration model agreed between Surfnet and GÉANT is for the fixed costs to be shared equally between each of the providers using the common fibre infrastructure. In the case of Amsterdam to Hamburg this is Surfnet, Nordunet and GÉANT. In future this may also include PSNC. Common costs are reduced by 2/3s compared to GÉANT only fibre. Solution also retains GMPLS control plane and ability to rapidly turn up new services. TeleGeography: huge demand (for alien waves) from nontraditional operators 6
Economics of alien waves Actual costs for Ams-Ham Ams-Ham, Alien Waves cost per 100Gbps 250,000 Annualized cost over 3 years in Euros 200,000 150,000 AW brings savings cf. leased waves with only 3 x 100Gbps 100,000 50,000 0 1 x 100 2 x 100 3 x 100 4 x 100 5 x 100 GÉANT DF 198,623 123,623 98,623 86,123 78,623 Leased Wavelengths 65,000 65,000 65,000 65,000 65,000 Alien Waves 98,623 73,623 65,290 61,123 58,623 7
Alien waves growth driven by content providers Most of the growth has been in content provider networks Source: TeleGeography 8
Alien Wave Field trial
Amsterdam Hamburg fibre Eliminating redundant fibre infrastructure R&E community has two parallel fibre systems between Amsterdam and Hamburg. Yellow cable is Surfnet. Green cable is GÉANT. Duplication of infrastructure dilutes utilization. Objective 1: remove one fibre system and share remaining fibre Objective 2: retain GMPLS control plane Solution: alien waves 10
Field Trial The setup Phase I Tested the technology and operational procedures. Objective was to understand if GÉANT can make use of SURFnet s dark fibre to carry our DWDM trunks. Fixed Filters Phase I used fixed filters to insert alien waves Convenient for fast trial, but does not scale well After successful competition of trail, the production solution will use ROADMs ROADMs allow waves to be remotely turned up and reduces inter-site fibres 11
Field Trial Connectivity DANTE Amsterdam Pair of loan AOLMs in the blue spectrum (OCG 2) SURFnet Amsterdam 6500 CPL SURFnet/Ciena line system Surfnet system operated in parallel with GÉANT production fibre for duration of trial N x amps SURFnet Hamburg 6500 CPL DANTE Hamburg Pair of loan ATCs with OLA and OFM-4-D AOLM- 500 AOLM- 500 AOLX- 500 Switch Matrix AOLX- 500 ATC N x amps ATC AOLX- 500 Switch Matrix AOLX- 500 AOLX- 500 OTC Existing AOLX on OCG 7 Existing DANTE fibre OTC DTN-X DTN-X
pre-fec BER pre-fec BER Field Trial Test results excellent receive margin Receive sensitivity measured on two wavelengths in each direction Better than 10 db receive margin in both directions i.e power into Rx can fall by 10dB before errors are seen AOLM-500-T4-1-C5 Hamburg Pre-FEC sensitiviy AOLM-500-T4-1-C5 Amsterdam re-fec sensitiviy 1.00E-02 1.00E-02 1.00E-03 1.00E-03 1.00E-04 1.00E-04 Ham 1556.56nm Ams 1556.56nm 1.00E-05 Ham 1554.94nm 1.00E-05 Ams 1554.94nm 1.00E-06 1.00E-06 1.00E-07 1.00E-07-30 -25-20 -15-10 -30-25 -20-15 -10 channel Rx power (dbm) Channel Rx power (dbm) 13
Field Trial Test results robust to input power variation 1.00E+00 1.00E-01 1.00E-02 1.00E-03 1.00E-04 1.00E-05 1.00E-06 pre-fec BER vs insertion loss at point of insertion of alien wave into fibre 1.00E-07-3.5-3 -2.5-2 -1.5-1 -0.5 0 1556.56 1554.94 Power injection is reduced at two points: Where the AW signal is injected into the fibre Where the AW signal is injected into the Ciena equipment In both cases the reduction in power did not result in a significant change in the pre-fec BER. Demonstrates that system is stable under power level changes. Pre-FEC BER @ AMS vs insertion loss at input to Ciena mux @ HAM 1.00E+00 1.00E-01 1.00E-02 1.00E-03 1.00E-04 1.00E-05 1.00E-06 1.00E-07-7 -6-5 -4-3 -2-1 0 1556.56nm 1554.94nm 14
Field Trial Test results Infinera alarms allow debugging of alien wave Alarms and notification aid debugging: four types signal deterioration can be distinguished 1. If there is a loss of fidelity of the signal, this can be detected using pre-fec threshold crossing notification 2. If the alien wave becomes so degraded that the Q-factor drops below 10, Infinera will raise a pre-fec Q out of range alarm 3. A cut in the SURFnet fibre results in a Loss of Frame (LOF) alarm, some signal from the optical amplifiers leaks through, so there will not be a Loss of Signal (LOS) alarm. 4. If the local patching between GÉANT and SURFnet sites is broken, then a Loss of Signal (LOS) alarm is raised. Infinera pre-fec Q out of range alarm Infinera Loss of Frame alarm 15
Alien Waves Next steps
Production Alien Wave Flexible solution uses ROADM technology These positive field trial results mean that GÉANT will go ahead and work with SURFnet to a solution that scales up to 5 x 100G of alien waves from Amsterdam to Hamburg. The production solution will use ROADMs for a more scalable solution. The addition of Wavelength Selective Switches (WSS) on the drop side of the SURFnet ROADMs adds support for colourless add-drop. This means that the multiplexed set of 10 x 50Gbps waves from the Infinera Photonic Integrated Circuit (PIC) can be injected straight into the Ciena ROADM without the need for fixed mux/demux. Reduces the number of optical patch cords between GÉANT and SURFnet racks.
Production Alien Wave Connectivity GÉANT Amsterdam PoP SURFnet Amsterdam PoP Up to 10 waves of 50Gbps each on single fibre pair DTN-X OTM OCG-7 AOLX interleaving OTC Ciena 6500 CPL WSS for Directional Independent Access (DIA) line side TrueWave reduced slope fibre AOLX- 500 Switch Matrix AOLX- 500 WSS WSS AOLX- 500 The use of a wavelength selective switch (WSS) on the access ports allows each wavelength to be individually turned up and adjusted
OTN & PXM Flexible capacity management
PXM in DTN-X Packet Aware OTN Core PXM: 200G Ethernet switch on a blade N x 10GbE Pt2pt ELINE or multipoint ELAN services. Built over OTN circuits 100GbE Packet Aware OTN Core N x 10GbE N x 10GbE Port Consolidation Transport Efficiency Stat-Mux Reduce router ports/fiber Improve router efficiency Aggregate packet flows Right-size transport Build ODUflex as needed Efficient optical protection Multiple flows combined Traffic profiles per flow Comprehensive QoS & TM
Old Eastern ring IP trunks follow fibre 100G 40G Routing layer Current IP architecture mirrors the underlying optical fibre links 100G 100G 100G 100G 40G As a result IP trunks chain through all routers 20G 20G 20G CH DE CZ Fibre layer Router interfaces are filled up with transit traffic IT AT SK HU SI HR 21
New eastern ring IP IP trunks follow traffic not fibre Trunks follow traffic rather than fibre 50G 50G 50G 100G 10G 50G 10G 10G 50G 50G 40G 10G 50G 10G Routing layer OTN allows flexible and rapid reallocation network services PXM cards allow multiple services to terminate on a single DTN-X 100G port FR CH DE CZ Transmission layer Allows for fine-grained allocation of GÉANT trunks Express links saves on high cost router interfaces IT SI AT SK HR HU Trunk capacity can be rapidly adjusted without the need to change routers interfaces 22
Summary GÉANT s first production alien wave has been commissioned on the Amsterdam- Hamburg section. Good stable operation with no bit errors. Operational model is well understood. The next AW system is planed to be from Hamburg to the Polish border. We have re-designed the IP trunks on the Eastern ring to make use of packet aggregation cards and router bypass. 23
guy.roberts@geant.org Thank you and any questions 24