Beyond 10 GbE – Looking
Ahead
Qwest Communications International
| Mark Stine, CTO | ||
| Government Services Division | ||
| February 2005 | ||
| What problem are we trying to solve ? | |
| How does price/technology/demand determine next step beyond 10 Gbps ? | |
| Where are we now ? | |
| 40 Gbps/ OC-768 or 100 Gbps ? | |
What problem are we trying
to solve? For Qwest
any new technology must result in:
| Revenue improvement | ||
| Enable new services | ||
| Product line consolidation | ||
| Increase market coverage; provide services faster | ||
| Manage disruption of legacy revenue | ||
| Cost reduction | ||
| Increase utilization | ||
| Reduce ports; minimize metallic interfaces | ||
| Increase power efficiency and equipment density | ||
| Minimize revisits to equipment | ||
| Remote operation | ||
| Operations simplification | ||
| Convergence, integration of networks | ||
| Ease provisioning, network configuration changes | ||
| Improve inventory management | ||
| Reduce engineering and planning complexity | ||
| Business goals driven by | ||
| – demand, capital, competition, relationships | ||
Qwest Multi-service, Packet Centric Infrastructure
How does 40 Gbps and 100 Gbps help?
| More efficient aggregation of traffic | ||
| Today’s large metro, West coast and East coast routes have sufficient demand to support higher TDM rates beyond 10 Gbps | ||
| Traditionally higher TDM rate easier to manage than DWDM | ||
| Minimizes or eliminates WDM channels | ||
| Could be fairly significant in the metro environment as cost avoidance to deploying a metro DWDM system | ||
| Reduces the number of customer interfaces to manage | ||
| Cheaper – 40 Gbps getting closer | ||
| Higher TDM rate interface cards typically prove in at 2.5 times the cost for 4.0 times the bandwidth. For example, 10 Gbps proved in at 2.5 times the cost of 2.5 Gbps | ||
| Solves customer application ??? | ||
Where are we today ? Qwest has demonstrated the largest known 10G/40G BW * D Field Trial
| Critical achievements: | ||
| ULH DWDM propagation of 85+ 10 Gbps channels at >3000 km with mixed span lengths on Qwest TWC fiber | ||
| 3x40Gbps and 88x10Gbps propagated over 1516 km | ||
40G Trial Configuration:1516km
Where are we going? Key Trends in Transport
| Metro Optical Networking – | ||
| Large scale EXC/MSPP with optical interfaces | ||
| 160Gbps-1.28Tbps capacity | ||
| OC-3c – OC-768(c) | ||
| VCAT combined with L2 capabilities | ||
| Metro Optical Ethernet – | ||
| Carrier grade L2 devices | ||
| Options for MPLS or VLAN traffic management/organization | ||
| Ethernet over dark fiber and over DWDM | ||
| Fast-E through 10G LAN PHY | ||
| Long Haul Optical Transport | ||
| Expansion of Ethernet in carrier transport space – Ethernet aggregation | ||
| Agile optical switching (OXCs, ROADMs) | ||
| Integrated 10G and 40G DWDM systems | ||
| Tunable and integrated optics | ||
| Optical control plane: GMPLS | ||
| G.709 digital wrappers | ||
| Ultra FEC | ||
| Raman amplification options | ||
Key Disruptive Optical Trends to Watch
| Optical component consolidation | ||
| Price disruption may drive optical architectures around these optical components. | ||
| Coherent modulation | ||
| May help enable 40 and 100 Gbps bit rates with lower symbol rates | ||
| Debate over opaque (digital) and transparent (analog) architectures | ||
| Depends on the network physical topology, demand set, applications, etc. | ||
| Some elements of both architectures will be optimal | ||
Optical component consolidation
| For the last 10 yrs we have been reducing the number of lasers in an optical transport network to reduce cost | ||
| Ultra Long Haul transponders/modulators, FEC, Raman to improve reach and reduce regeneration | ||
| Transparency to reduce through traffic regeneration | ||
| What if the costs of lasers and optical components became cheap? Different paradigm. Very disruptive. | ||
| Consolidation of multiple discrete optical components onto silicon | ||
| Chip yields in full production environment?? | ||
Coherent Modulation - Radio Communications 101
| Today’s optical transport equipment uses OOK modulation | ||
| Some version of NRZ, RZ, & CS-RZ formats | ||
| Future coherent modulation is disruptive in the long haul | ||
| QPSK, PSK, dQPSK, dPSK, QAM, etc | ||
| Offers up to a theoretical gain of 3 dB OSNR over OOK | ||
| More complex receiver design | ||
| Appears to be more tolerant to some nonlinear effects, chromatic dispersion and PMD | ||
40 Gbps - Challenges and Answers
| Fiber | ||
| PMD on older single mode fiber | ||
| Costs | ||
| Not quite there | ||
100 Gbps - Challenges and Answers
| Fiber | ||
| PMD serious problem on today’s fiber, requires PMD compensators | ||
| Dispersion managed fiber likely required and active dispersion compensators | ||
| Component and material limitations | ||
| Transmitter/Receivers – near electro-optics limits, may require OTDM vs ETDM | ||
| Lasers – very narrow, high repetition pulse rate with low jitter | ||
| Processors – processing at line rate challenging (limits FEC, for example) | ||
| System concerns | ||
| Channel spacing fairly wide to avoid FWM | ||
| OSNR challenged for current long haul amplifier spacing | ||
| Nonlinear effects: SPM, XPM | ||