DOCSIS 3.1 roll Out First Lessons Learned DOCSIS 3.1 roll Out First Lessons Learned Pay utmost attention to noise, and how to eliminate it Avoid cold-flow phenomena Terminate DOCSIS service in the first outlet Necessary to use equalizers to align Choose your partners carefully
Presenters: DOCSIS 3.1 roll Out First Lessons Learned With focus on the passive distribution network Christian Emborg CEO, DKT A/S Peter Bukhave Hansen Vice President, Coax networks, TDC Group A/S Intro TDC has started a complete upgrade of the coaxial network to a full blown DOCSIS 3.1 solution. The findings presented are based on preparations and first field experience. Key findings/overview: Pay utmost attention to noise Avoid cold flow phenomena Terminate DOCSIS service in the first outlet Necessary to use equalizers to align Choose your partners carefully
Overview Project status on the TDC roll out Quick overview of reasons to invest Where is the project today (start June 2016)
Why Why: We want to be best for the customers Key selling points for individual and organised customers Traffic driven capacity costs not sustainable Why this solution: D-CCAP: All-IP, scalable, future proof Network transformation: Superior spectrum and capacity efficiency Why now: Better than the competition Immediate benefits 4
Exponential increase in usage and service offerings Average commercially sold downstream speed in Denmark Average weakly peak ½ hour traffic per customer in one segment 1.000 Historical data Projection 10000 Average speed increases 22% YoY Mbps 100 10 Average downstream traffic increases 42% YoY kbit/s 1000 100 1 2005 2010 2015 2020 2025 10 2010 2015 2020 2025
Key selling points for our customers End-user Higher internet speeds Higher TV and VOD video quality More bandwidth - less congestion More robust and stable service Much better wifi with new cable modem Network owner New high speed offerings More capacity in the network (pr segment) More robust network, fewer network errors Easier and cheaper to maintain Faster fault and error correction Future proof Already Gigabit/s but more is coming e.g. Full Duplex 6
Planned distributed Docsis 3.1 all-ip architecture Today Capacity: 912/162 Mbps Speed: 500/60 Mbps 32 POPs Generates the TV signals Docsis 3.0 CMTS (for broadband) POP In ~70 central offices ~2800 Modem TV Headend POP POP Optical HUB Optical node POP IP transport TDC s common IP transport network IP multicast for TV High availability, automatic fail-over Analogue optical transport DWDM between POP og HUB Up to 80 km links No automatic fail-over No support of Docsis 3.1 ~75.000 amplifiers Coax cables 5-65 MHz upstream 87-862 MHz downstream From Docsis 3.0 to Docsis 3.1 More frequencies + higher efficiency 10 times more capacity With Gigaspeed Capacity: Up to 10.000/1.500 Mbps Speed: 1.000/500 Mbps >4000 D-CCAP Docsis 3.1 CMTS for broadband Generates the TV signals (in end state) ~200 central offices Headend OLT D-CCAP Modem TV IP transport TDC s common IP transport network IP multicast for TV High availability, automatic fail-over ~72.000 new amplifiers Digital transport over fiber XGPON Only a few km links Coax cables 5-204 MHz upstream 258-1218 MHz downstream 7
Transformation leads to network homogenety Tabs Splitters Number Models ~ 330.000 >360 models ~ 250.000 >500 models Less noise Fewer errors Higher modulation Amps ~ 75.000 >30 models More homogenous Higher speeds Better video quality 8
Noise threatens implementation of D3.1 Constellation Diagram self-explanatory QAM256 QAM4096
The example shows that a normal case scenario will result in a S/N on 25dB = reduced speed on the return path! How do we increase to the necessary 37dB?
Solution: remove any source of noise when possible Noise sources: Network + Home Remove noise from the main sources!! This is how TDC will do it: 1. Nickel-tin plated brass connectors on the passives Prevents the loosening of connectors (non-coldflow) Prevents CPD/corrosion = possible noise reduction of 1 10 db 2. Terminate the DOCSIS 3.1 at the entry to the home Noise contribution from in-home installation eliminated = possible noise reduction of 8 10 db
Change in Modem Transmission Level Window necessary! Why? Return Path Signal Level % Modem transmission level With a low transmission level 9,0 the CNR is too low for QAM1024 8,0 modulation index, meaning the 7,0 upload speed has to be 6,0 reduced. 5,0 4,0 3,0 2,0 1,0 0,0 120 119 118 117 116 115 114 113 112 111 110 109 108 107 106 105 104 103 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 High return path attenuation High transmission level Low return path attenuation Low transmission level With a high transmission level the modem cannot increase its total transmission power level, so the bandwidth of the upstream signal cannot be enhanced, meaning the upload speed cannot be increased to the full DOCSIS 3.1 speed. How do we solve that?
Equalizers will align to optimize use This is how TDC will do it 2m 35m 4dB Attenuation: 20MHz: 29.4dB 1218MHz: 38.1dB Conclusion: Equalizers force a higher attenuation for the far end subscriber s signal = S/N >37dB & modem output capacity for 192MHz QAM 1024 35m Adding 3 Equalizers 35m 35m 5dB 2dB Attenuation with Equalizers: 20MHz: 29.6dB 1218MHz: 43.8dB
Key learning point in the process Process key learning points Choose your partners carefully Make sure that you have the right competencies on the team
Key learnings Equipment Certifications Cable modems Amplifiers D-CCAP Project Knowledge and experience Dedicated organisation Best of breed suppliers Commercial commitment Design FM radio band 88-108 MHz Frequency planning All-IP network Distributed architecture Real world Get documentation in place Communication Practise and train Test, test, test Celebrate 15
Network quality improves after transformation - and many learning points in the process 100,00 95,00 Average last 28 days 90,00 Before 85,00 80,00 After 75,00 70,00 65,00 Network KPI is calculated using 7 different parameters measured realtime 16
Geocodes, bar codes and apps: Better documentation, faster trouble shooting, better quality 17
How to get a good start with a D3.1 upgrade Conclusion/Summary Pay utmost attention to noise, and how to eliminate this Avoid cold flow phenomena Terminate DOCSIS service in the first outlet Necessary to use equalizers to align Choose your partners carefully