1. Page 1 Page 1 Technology and Architecture to Enable the Explosive Growth of the Internet Abu (Sayeem) Reaz University of California, Davis, USA Group Presentation February 08, 2011 Adel A. M. Saleh, Jane M. Simmons

2. Page 2 Page 2 A high-level vision for addressing the challenges based on both technological and architectural advancements

3. Page 3 Page 3 Traffic Growth Predictions Current annual rate of growth is 40 to 50 percent 1 Internet will grow at a compound rate of 35 percent from 2008 to 2013 2 Year-over-year IP traffic growth rate to be 45 percent 3 1. A. Odlyzko, “Minnesota Internet Traffic Studies (MINTS)”; www.dtc.umn.edu/mints/home.html 2. Cisco, “Visual Networking Index: Forecast and Methodology, 2008–2013,” White Paper, June 9, 2009 3. A. Colby, “AT&T, NEC, Corning Complete Record-Breaking Fiber Capacity Test,” May 11, 2009; news.soft32.com/att-nec-corning-complete-recordbreaking-fiber-capacity-test_7372.html ~ 40%

4. Page 4 Page 4 Traffic Growth Rate Level of traffic for various compound annual growth rates (CAGR). At 40 percent CAGR, the traffic level will increase by a factor of 1000 in roughly 20 years. ;V(t 0 ) : start value, V(t n ) : finish value, t n − t 0 : number of years

5. Page 5 Page 5 Current Network Condition Current 80 × 40 Gbps transmission systems are about 1/3 full  A growth of 350 times needed Optical Bypass  Less electronic terminating equipment Optical reach is at the order of 2000 km to 2600 km We need to have our cake and eat it too!

6. Page 6 Page 6 To Meet the Challenges… Technological advancements increase the realizable capacity of fiber and routers/switches Architectural enhancements decrease the traffic burden on the network

7. Page 7 Page 7 Transmission

8. Page 8 Page 8 Technology: Spectral Efficiency Spectral efficiency: the ratio of the information bit rate to the total bandwidth consumed 80 × 40 Gbps  spectral efficiency of 0.8 b/s/Hz 80 × 100 Gbps  spectral efficiency of 2.0 b/s/Hz Realizable spectral efficiency limit  ~ 4 b/s/Hz per polarization  80 × 400 Gb/s system with Dual-polarization “As compared with today’s 40 Gb/s systems, 8 b/s/Hz represents a factor of 10 increase in transmission capacity, which is clearly insufficient to meet long-term projections of traffic growth.”

9. Page 9 Page 9 Technology: Expanded Transmission Band C band: conventional (“erbium window”)  1530–1565 nm L band: long wavelengths  1565–1625 nm L-band is the most likely choice for expansion  ~65 nm of spectrum across the C- and L-bands (a current system * already supports 54 nm across the C- and L- bands with a single amplifier) A single amplifier across the spectrum and tunable transponders Expanding the transmission band will result in a factor of two increase in system capacity; e.g., a 160 × 400 Gbps system * D. A. Fishman, W. A. Thompson, and L. Vallone, “LambdaXtreme Transport System: R&D of a High Capacity System for Low Cost, Ultra Long Haul DWDM Transport,” Bell Labs Tech. J., 2006.

10. Page 10 Page 10 Technology: Multicore Fiber Multiple fibers  scaling of optical amplifiers & port-size of all- optical switching devices (e.g., ROADMs)  higher cost + energy Multiple core per fiber with all the benefits of single-core fibers Operational with single amplifier and connector with about 2500 km reach Major challenge: cross-talk across cores, still in “demo” Seven cores per fiber with spectral efficiency and expanded band yield about a factor of 140 increase in capacity of transmission systems

11. Page 11 Page 11 Architecture: IP Packing Burstiness of IP traffic  “headroom”  avg. fill rate of IP links in the US Internet is about 25% ↓ IP Flow + ↑ Line-rate = smoothness  fill rate 65% is feasible This benefit is for IP traffic only IP Packing yields about a factor of 2 benefit!

12. Page 12 Page 12 Architecture: Multicasting, Asymmetric Traffic, Improved Caching Multicast when possible (e.g., Video Distribution) Provision as needed  Asymmetry (and MLR!) Internet as Cloud  store and let store at a nearby location Outcome depends on application A combination of these yield about a factor of 4 benefit!

13. Page 13 Page 13 Architecture: Dynamic Networking Reconfigurable equipments such as ROADMs and tunable transponders enable remote and dynamic connection setup A “push-pull” area of development  research underway to provide setup time on the order of 100 msec to 1 sec Delivers bandwidth when and where needed  decrease network cost and capacity requirement Dynamic networking yields about a factor of 5 benefit!

14. Page 14 Page 14 Factors Affecting Transmission

15. Page 15 Page 15 Routers

16. Page 16 Page 16 Technology: IP Routers The focus is IP layer  finer granularity and more challenging to scale Increased router size: higher cost and power consumption Even with 20% better power efficiency per year *, after 20 years, a single 3000 Tbps router will consume 350 KW “Even if larger routers are possible, the operational challenges of deploying such a large device are impetus to consider architectural innovations that can mitigate their need.” * J. Baliga et al., “Energy Consumption in Optical IP Networks,” IEEE/OSA JLT, 2009

17. Page 17 Page 17 Architecture: IP Packing Higher fill rate for IP traffic  lower # of wavelengths needed to carry the traffic Translates to half as many ports needed on the IP routers

18. Page 18 Page 18 Architecture: Optical Aggregation Optical aggregation more suitable for edge as they usually require collision management and/or scheduling Increased amount of traffic can be efficiently packed at edge  does not undergo further grooming at core Reduced burden at core IP router  lower electronic processing

19. Page 19 Page 19 Architecture: Others Multicasting, Asymmetric Traffic, Improved Caching, and Dynamic Optical Networking Many connections that will benefit from these factors represent wavelength services, which probably will bypass the IP routers. As a result, their contribution may be small

20. Page 20 Page 20 Factors Affecting IP Router Size

21. Page 21 Page 21 Summary Internet traffic is doubling approximately every two years, leading to a factor of 1000 growth in the next two decades Requires advances in both technology, to increase the capacity of transmission and routing/switching systems, and architecture, to effectively reduce the capacity requirements Addressed only the backbone portion of the network, access networks will need to scale as well, through a combination of advanced broadband fiber, cable, and wireless technologies