Keeping up the momentum: The importance of innovation to keep networks fit for the future Dr Tim Whitley MD Research & Innovation, BT Distinguished

Transcription

1 Keeping up the momentum: The importance of innovation to keep networks fit for the future Dr Tim Whitley MD Research & Innovation, BT Distinguished Engineer

2 Context Trends Increasing consumer and business data usage: Device penetration (tablets, smartphones, smart TVs); Video usage across all device types; Internet of things, wearables etc.. Increased bundling of services: Convergence of content/tv and broadband; Convergence of fixed and mobile; Challenges for BT To provide enough capacity to keep up with demand. To devices that customers want to use, wherever they are and when they want to use it. At reasonable cost. To offer seamless connectivity requires integration of fixed and mobile networks. Manage implications for core network Voice heading towards being an application on IP. 2

3 Access BT s Broadband Heritage August 2000: BT Launched 500kbps ADSL broadband G.fast September 2004: BT removes distance limitations for ADSL VDSL March 2006: BT Launches 8Mbps DSL Max ADSL April 2008: BT Launches 24M Wholesale Broadband Connect Broadband January 2009: BT Infinity / Fibre Broadband launched April 2012: 80Mbps FTTC launched November 2012: 10G PON trial in Cornwall Narrowband August 2013: 300Mbps Infinity product launched Spring 2014: Scale Vectoring Trial Summer 2014: G.Fast technology trial Copper speeds: advances over time 3

4 The access network 5600 locations <2.2MHz, Typ 3.5km length ~89k locations <17MHz, Typ 350m length ~4M locations <106MHz, Typ ~35m length ~29M locations Fibre to the Cab Fibre to the DP Fibre to the Premise 4

5 Access broadband Innovations Driving faster speeds FTTC Vectoring FTTRN VDSL closer to the customer FTTDP G.Fast FTTP Extending reach We are innovating to extend benefits of faster access to the final c. 10% of coverage Copper rearrangement Broadband regenerators for ADSL Microwave wireless to the cabinet VDSL amplifiers Vectoring Fibre to the remote node (mini DSLAMs) Cabinet 5

6 Maximum Downstream bit-rate (kbit/s) Max Attn Bit Rate (kbps) The impact of crosstalk and vectoring Crosstalk generation within a cable Crosstalk is due to coupling between pairs in a multi-pair copper cable and limits FTTC speeds. Increasing cable fill through customer take-up increases crosstalk and Signal 1 Signal 2 Signal 3 line 1 line 2 line 3 reduces line-rates. By calculating a pre-compensation factor for each line, the crosstalk Cable binder Vectoring gain (laboratory measurement) can be cancelled in the DSLAM The technique for doing this is called Vectoring, and is conceptually similar to noise cancelling headphones Openreach has trialled six vectored cabinets with c.1000 live customers in Braintree and Barnet. Phase 2 trials are now underway Cable Length (m) Performance without Vectoring Performance with Vectoring 6

7 Pushing fibre deeper into the network: the Distribution Point Beyond the green cabinets, BT has overhead and underground DPs with: An average of ~8 customers connected; Can have >16 customers in some cases. Typical pole DP serving 12 customers Space is limited and they are exposed to the elements. The typical distance from the DP to the customer is ~35m making it the ideal location for delivering very high speeds. A new technology (G.fast) is being standardised in the ITU: Enables speeds of up to 1 Gbit/s; Commercial G.Fast equipment is expected in H2 15/16. Typical distribution footway joint box 7

8 We have trialled G.Fast in the network Trial had three customers connected to one DP The network was overlaid to prevent harm to existing services, but used existing duct infrastructure Chart shows best and worst case performance Physics of G.Fast worked as expected Vectoring proved to be critical in delivering the top speeds 19m 19m 10G backhaul 66m 19m 66m 66m 47m 8

9 BT is opening a new, purpose-built, ultrafast broadband lab at our Adastral Park R&D centre in Ipswich Emulation network enables G.Fast has demonstrated potential that now needs to be tested and verified. replication of different realworld final-drop topologies We will study the full technical capabilities of G.Fast hardware designed by leading system vendors. We will continue to play a proactive role in developing G.Fast standards in the ITU. It s crucial that we stay ahead of the curve for the benefit of our customers and shareholders. DP and CPE installations allow a full range of performance and operations tests 9

10 FTTP 10G and beyond GPON provides 2.5Gbit/s downstream, 1.2Gbit/s upstream XG-PON1 provides 10Gbit/s downstream, 2.5Gbit/s upstream Exploiting existing Fibre Network with separated wavelengths XG-PON and GPON coexist on the same fibre No change to Optical Distribution Network (ODN) WDM1r (Filter) component already in place We are working on NG-PON2 which provides 40Gbit/s GPON GPON OLT 2.5Gbit/s & 10Gbit/s downstream and 10Gbit/s upstream on a single PON system (1490nm & 1577nm) Power splitter GPON ONT WDM1r XG-PON1 ONT XG-PON1 system XG-PON1 OLT 1.24Gbit/s & 2.5Gbit/s GPON ONT (1310nm & 1270nm) 10

11 Core traffic (Tbit/s) Access fibre deployment and new services will drive future core bandwidth demand Current core traffic growth CAGR = 45%. Bandwidth demand analysis to 2033 suggests core requirement of c.12tbit/s by Time of day activity scenarios have been used to model bandwidth demand of different user types Key future demand drivers: Future demand mitigation: Over the Top content; Improved video coding; 70 Video on Demand; 4k/8k content delivery; Time-shift delivery techniques Low Scenario Mid Scenario High Scenario Cloud-based applications; 40 Modelling suggests HD Video-calling; c 25 to 30 fold core 30 Rich media webpages; capacity increase 20 Software package size growth; over the next ten 10 Customer expectations of speed. years Potential long-term core capacity requirements 11

12 Bandwidth BT s upgrades core transmission roughly every ten years... 1Tbit/s 100Gbit/s UBB 1G-10G 21C WDM 1G-10G NG-WDM 40Gbit/s 10Gbit/s 1G, 10G, 40G, 100G 2.5Gbit/s 622Mbit/s SDH MESH SDH rings 155Mbit/s PDH Megastream 34Mbit/s Mbit/s 155M -2.4G Private Circuits PSTN Broadband, 2Mbit/s Kilostream ATM & IP PSTN We are now deploying 100Gbit/s coherent optics 64Kbit/s Year 12

13 The Next Generation: 400G & Terabit Trials 2T 2T & Beyond S/W Configurable modulation formats 1T 1.4T Alien Flexgrid Super channel 800G Super channel 400G & 200G (16-QAM) Cambridge Norw ich Alien Wavelengths TNOC 83km 77km Coherent New market 100G 40/100G Cambridge 50.7km 24km 68km Ipswich 13.5km Adastral park Bishops Stortford 52km Wood green 58km 64km 29km Colchester BT Adastral Park 14km 62km Basildon BT Tower BT Tower 13

14 The Next Generation: Gridless & Optical Superchannels Current WDM has rigid 50GHz grid structure. Future gridless infrastructure permits improved fibre utilisation (spectral efficiency). Example: 1.4T Superchannel comprising 7 x 200G (16-QAM) subchannels 14

15 Pushing the boundaries 400GHz We have demonstrated real-time 2.2T Transport over managed Flexgrid infrastructure: 2.2T Superchannel 11 x 200G 16-QAM Superchannel; 33.5GHz subcarrier spacing giving a spectral efficiency of 5.97bits/s/Hz, more than 49% improvement over conventional 2.2T (11 x 200G 16-QAM) 50GHz grid. We are working with partners to develop our understanding of capacity management, for example: 100G 100G Demonstrating configurable Superchannel alongside multiple 100G 50GHz grid channels; Working with Huawei U2000 management system. Superchannel Configurable Superchannel operating alongside 100G grid channels 15

16 The next challenges are control, flexibility and vendor interoperability... SDN datacentre & network orchestration Datacentre with general purpose H/W suitable for NfV SDN orchestrating the provision of virtualised network functions Software Defined Networking (SDN) Network functions Virtualisation (NfV) Open standard control and orchestration equipment Reduced costs through consolidating functions Setting up optical and Ethernet circuits on the fly Reduced operational costs Control of flexgrid bandwidth and optical modulation formats Rapid provision of new services globally Multilayer operation allowing time of day router bypass Software oriented innovation (including Open Source) 16

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