For those interested in HFC and DOCSIS with a base knowledge of TCP/IP and RF concepts. Presented on the 22/3/16 to TCP/IP Student Group at Swinburne University of Technology

1. (Very) Quick Intro to HFC and DOCSIS 3.0
Presented, 22nd of March 2016 to SUT - TCP/IP Group
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2. Erik Vloothuis
Member of SCTE
Current Swinburne University of Technology Masters Student:
MEngSc(Telecommunications and Networks Systems)
Some experience:
DOCSIS1.1 with VoIP 2002
FTTH P2P - VoIP, TV, Data 2003/4
FTTH EPON - VoIP, TV, Data 2005
The obligatory disclaimer: My own views, For educational use only.
Further relevant sources: Cablelabs and SCTE
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3. HFC - Overview
RF in HFC
DOCSIS 3.0 - What?
DOCSIS 3.1 - Some Differences
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4. Breaking it down - Key Components
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5. Breaking it down - the dependent layers to deliver
DOCSIS - OSI reference
HFC - Nodes, Amps, Taps, Segmentation, TX and RX
LAYER 1
LAYER 2
LAYER
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RF - Spectrum Plan - TX and RX
PHY DOCSIS - Carriers and Modulation - TX and RX
MPEG Framing, TDMA Control
IP DOCSIS - DOCSIS Control Messages
MAC DOCSIS - CMTS to CM PHY management
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6. Breaking it down - Layer Interaction and flow
*Image Source SCTE
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7. Breaking it down - Layer 1 - the HFC Access Network
*Image Source SCTE
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8. • Optical Node - 1X Forward Path only (PayTV) 1990BI
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9. • Optical Node -1X Forward and 1X Reverse Path
• PayTV, Telephony + Data now possible (DOCSIS > 1997)
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10. • Optical Node - 1X Forward and 2X Reverse Path
• Increased Upstream BW
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11. • Optical Node - 2X Forward and 2X Reverse Path
• Increased Downstream + Upstream BW
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12. One Optical Node - Many configurations!
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13. Optical Nodes - Installed on-span or in cabinet
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14. 5 - 1005 MHz
5 - 65 85 - 1005 MHz
Forw
ard
Path
Reverse
Path
• 6-8MHz Digital Carriers, QAM 64-256 Modulated
• 200Hz - 6.4 MHz Carriers QPSK - QAM64 Modulated + S-CDMA
Breaking it down - Layer 1 - the RF Network FDM
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15. 5 - 1005 MHz
5 - 65 85 - 1005 MHz
• 6-8MHz Digital Carriers, QAM 64-256 Modulated
• 200Hz - 6.4 MHz Carriers QPSK - QAM64 Modulated + S-CDMA
Breaking it down - Layer 1 - In the Freq domain
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16. Layer 2 - MAC - DOCSIS TDMA - Minislots
*Source SCTE
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17. Layer 2 - MAC - DOCSIS Frame - incl. MPEG headers
*Source SCTE
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18. 5 - 1005 MHz
5 - 65 85 - 1005 MHz
• Downstream - Minimum 4 Carriers - some CM’s have 24
• Upstream - Minimum 4 Carriers - some CM’s have 16
Layer 2 - MAC - DOCSIS 3.0 Channel Bonding
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19. DOCSIS versions and Channel Bonding Speed
*Table Sourced from SCTE
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20. Quick summary of getting to DOCSIS 3.0
HFC - We can scale RF Capacity
RF - We can choose Modulations to 256QAM
RF - We can use Synchronous-CDMA (SF to support 128CM)
MAC - We use TDMA and MPEG framing
We already have QOS, BPI, IPv6, SCDMA etc..(from D1.1, 2.0), with a equal
services at a maximum distance of the CMTS to CM of 160km
(rare that maximum distance is deployed, but possible).
and with DOCSIS 3.0, we can now channel bond
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21. The DOCSIS Evolution
*Table Sourced from SCTE
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22. DOCSIS 3.0
6.3Gbps Down / 450Mbps Up per Optical Node (HFC segmentation still possible)
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23. 5 - 1005 MHz
5 - 65 85 - 1005 MHz
• Downstream - Minimum 4 Carriers - some CM’s have 24
• Upstream - Minimum 4 Carriers - some CM’s have 16
Remember DOCSIS 3.0 Channel Bonding
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What about DOCSIS 3.1??? Back to the Spectrum

24. DOCSIS 3.1 - Massive change in MAC and PHY
5 - 1800 MHz
5 - 204 258 - 1794 MHz
• Downstream - 192MHz wide COFDMA 25-50KHz Sub-carriers @ 4096QAM
• min 5 capable , up to 8
• Upstream - 95MHz wide COFDMA 25-50KHz Sub-carriers @ 4096QAM
• min 2 capable
Single carrier concept removed - Now COFDMA
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25. DOCSIS 3.1 - Co-Existence
5 - 1800 MHz
5 - 204 258 - 1794 MHz
• D3.1 Channels can be split and moved to accomodate existing services
or cable plant environment <<< Manageable Transition!!!
• Each 25KHz sub carrier can then be individually modulated to the
highest order feasible. <<< Flexibility!!!
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Living with the neighbours ……

26. DOCSIS 3.1 Forward Path Possibilities
Table Sourced from CISCO
5 x 192MHz Channels @ 4096QAM = 9.45Gbps
8 x 192MHz Channels @ 16384QAM* = 17.68Gbps
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27. DOCSIS 3.1 Reverse Path Possibilities
*Table Sourced from CISCO
2 x 95MHz Channels @ 4096QAM = 1.88Gbps
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28. 9.24 Gbps Down / 1.88Gbps Up per Optical Node @4096QAM - min supported spec
17.68 Gbps Down / 1.88Gbps Up per Optical Node @ 4096QAM / 16384QAM - upper spec
HFC segmentation still possible, Plant must be capable!
DOCSIS 3.1
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29. Questions ?
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30. Thank you
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