DOCSIS 3.0 DS Planning & Bandwidth Management John Downey, Consulting Network Engineer – CMTS BU

DOCSIS 3.0 DS Planning & Bandwidth Management

John Downey, Consulting Network Engineer – CMTS BU

© 2010 Cisco and/or its affiliates. All rights reserved. Cisco Confidential 2© 2010 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialC97-552046-00 2

• Objectives

• Terms

• M-CMTSAdapters and connectivity, linecards, timing servers, e-qams, ..

• I-CMTS

• Optional Architectures

• Frequency Stacking Levels

• Frequency Placement

• Isolation Concerns


• Why it’s NeededCompetitive pressure, offering higher tiers of service, more

customers signing up

• Frequency Stacking Levels & PlacementWhat is the e-qam max output with four channels stacked

Do channels have to be contiguous?

• Isolation ConcernsApplications w/ different service grps lead to overlaid networks

Signals destined for one node could “bleed” over to another

• DS Frequency Expansion to 1 GHzAmplifier upgrades are occurring now. It’s best to make the truck

roll once, so think about diplex filters, spacing, taps, etc.


• Allow more BW for DOCSIS 1.x & 2.0 CMs

• Limit/reduce more node splits

• Introduce new HSD service of 50 to 100 Mbps

• Allow migration of existing customers to higher tier and DOCSIS 3.0 capabilityBetter Stat Muxing


• Local DS = CMTS DS• Remote DS = E-QAM DS• Primary = DOCSIS messaging• Secondary = Bonding• “Wideband” generically used to describe D3.0 DS bonding• Channel Grouping Domain (CGD) is MxN mac domain

Mac Domain = 1 DS & N USs

• Service group = CMTS Fiber Node config• M-CMTS is an architecture, not necessarily D3.0

Provides DS load balance within MxN domain

• I-CMTS allows MxN and bonding within linecard• D3.0 CM supports minimum of 4 US and 4 DS chs• CMs on market are 4x4 (TI-based) & 8x4 (Brcm-based)


• Uses M-CMTS compliant Edge-QAMCisco RFGW-1D and RFGW-10

Harmonic NSG-9000

• Increase legacy DS port density of uBR10K

• Uses DTI timing source for DS channels

• Enables legacy DOCSIS [1.x/2.0] CMs to use external QAMs for operationAllows MxN mac domains

• Eliminates need for PC from 5x20 card

• Allows bonding on all channels in a BGHits the 100 Mbps BW mark on a 3-channel CM


L1/L2/L3 CIN

uBR10k

5X20

SPAEQAM

CM 1Legacy Modem

CM 3Legacy Modem

CM 43-Channel Bonding

DS 4

DS 3

DS 2

DS 1

US 1

DTI Server

CM 23-Channel Modem

doing 2-Channel Bonding

Eightbells


• CMTS

Cable linecard

US ports needed and host

DS bonding adapter

1 Gbps fiber or copper ports

DTI timing card

• DTI Server (Symetricom)

• M-CMTS compliant EQAM

Cisco RFGW-1D or RFGW-10

Harmonic NSG9000

Arris

• WCM300 (Linksys BroadLogic)

• SA 3-Ch DPC 2505 (BCM 3381)

• Cisco/SA DPC 3000 4x4 TI

• Cisco/SA DPC 3010 8x4 Brcm


CM CM CMCMSA DPC

3000

MC5x20H

CPU/RP

Jacket Card

uBR10KCMTS

D3.0 DS + Primary

NB DS

WB DSSPA

WB DSSPA

Backhauls

SA DPC-2505

Primary Ch

D3.0 BG

Primary

DTI Card

DTI Card

DTI Server

M-C

MT

S E

QA

M


• Any rules-of-thumb to estimate service group size?

• What recommendations are there for HE combining/splitting to avoid intrusive changes later?

• Any impairments in HE or plant that will affect DOCSIS 3.0 more compared to earlier versions? Isolation

Off-air Ingress

Attenuation

Freq assignments, spectrum allocation, plant limits

• If small amount of extra BW needed, is it possible to split 4 chs from DS port to use 2 chs in one SG and other 2 in another SG?


1x2

1x2

1x2

1x2

eQAM

609, 615, 621, 627 MHz

8/0/2

22 & 28 MHz6.4 & 3.2 MHz

Slot 8/0

1x2

eQAM

8/1/08/1/1

8/1/28/1/3

8/0/08/0/1

8/1/4

8/0/38/0/4

eQAM

6/0/0, 6/0/1, 6/0/2, 6/0/3, 6/0/46/1/0, 6/1/1, 6/1/2, 6/1/3, 6/1/4

5/0/4

5/0/05/0/1

Ups

tre

am

US0

US2

US4

US16

Dow

nst

rea

m

DS0

DS1

DS2

DS3

DS4

US14

US12

US10

US8

US6

US18

1/0/

0S

PA

3/2/

010

GE

3/3/

0S

PA

PR

E4

PR

E4

Slo

t 5/0

1/2/

010

GE

1/1/

0S

PA

1/3/

0S

PA

3/0/

0S

PA

3/1/

0S

PA

Node 1

Node 2

Node 3

Node 4

Node 5

Node 6

Node 7

Node 8

Node 9

Node 10

Ser

vice

Gro

upS

ervi

ce G

roup

Ser

vice

Gro

upS

ervi

ce G

roup

Ser

vice

Gro

up

7/0/0, 7/0/1, 7/0/2, 7/0/3, 7/0/47/1/0, 7/1/1, 7/1/2, 7/1/3, 7/1/4

5/0/2, 5/0/3

4x1

4x1

4x1

4x1

4x1

• 5 DS frequencies

1 I-DS

4 M-DS

(5 Primary)

2 US frequencies

2 channel bonding


B

P PP P

Bonding across 4

freqs & 5-ch load

balance for legacy CMs

603

609

FN1 FN2 FN3 FN4 FN5 FN6 FN7 FN8

22

Frequency

ATDMA

B

TDMA

P

P

28

615

621

627

P

P

B

P

P

P

P

B

P

P

P

P

B

P

P

P

P

P

B

P

P

P

P

FN9 FN10

• 5, 5x4 MAC domains with ATDMA & TDMA USs• E-qam overlaid for 2 nodes 70/2 = 35 connectors• 3 e-qam chassis with 6 modules each• 4 freqs * 35 = 140 QAMs = 6 SPAs = Spumoni & PRE4

• 5 DS freqs

• 2 US freqs

16-QAM

64-QAM

3.2 MHz

6.4 MHz

Local Bonding

Remote PrimaryP

P Local Primary

B Remote Bonding


1x2

1x2

1x2

1x2

22 & 28 MHz6.4 & 3.2 MHz

Slot 8/0

1x2

Ups

trea

m

US0

US2

US4

US16

Dow

nst

ream

DS0

DS1

DS2

DS3

DS4

US14

US12

US10

US8

US6

US18

1/0/

0S

PA

3/2/

010

GE

3/3/

0S

PA

PR

E4

PR

E4

Slo

t 5/0

1/2/

010

GE

1/1/

0S

PA

1/3/

0S

PA

3/0/

0S

PA

3/1/

0S

PA

Node 1

Node 2

Node 3

Node 4

Node 5

Node 6

Node 7

Node 8

Node 9

Node 10

Ser

vice

Gro

upS

ervi

ce G

roup

Ser

vice

Gro

upS

ervi

ce G

roup

Ser

vice

Gro

up

4 DS frequencies (4 I-DS) 2 US frequencies

2 channel bonding


Bonding across 4

freqs & 4-ch load

balance for legacy CMs609


22

Frequency

ATDMA

B

TDMA

P

P

28

615

621

627

P

P

B

P

P

P

P

B

P

P

P

P

B

P

P

P

P

B

P

P

P

P

FN9 FN10

• 5, 4x4 MAC domains with ATDMA & TDMA USs• DS connector overlaid for 2 nodes, 35 connectors*2 = 70 nodes• 4 freqs * 35 = 140 QAMs = PRE4

• 4 DS freqs

• 2 US freqs

16-QAM

64-QAM

3.2 MHz

6.4 MHz

Local PrimaryP

B Local Bonding


• Pros Four bonding freqs / e-qam connector Only 1 e-qam connector per 8 nodes Basic = 2 DS/2 nodes with DCC support US load balance of 2.0 CMs One US connector shared across 2 nodes

for diminishing D1.x CMs

• Cons Requires M-CMTS architecture Requires five DS & three US freqs Must push 3.0 CMs to remote DS Bonding group must be same IP bundle CM ranging overlap with “real” data?

P PP P Basic

Extended

603

609

615

621

32


22

Frequency

ATDMA

ATDMA

S

627

37 TDMA

P

P

P

P

3.2 MHz

6.4 MHz

RemoteDSs

LocalDSs

• 5 DS freqs

• 3 US freqs

• 2x5 domain


• Pros 8 bonding freqs per 2 connectors Only 5 connectors per 8 nodes

Can provide 8 ch DS bonding US load balance of 2.0 CMs One US connector shared across 2 nodes for

diminishing D1.x CMs

• ConsRequires 8 DS & 3 US freqs

Extended

609

615

621

32


22

Frequency

ATDMA

ATDMA

S

627

37 TDMA

P

P

P

P

B

PPPP

B

PPPP

B

PPPP

B

PPPP

3.2 MHz

6.4 MHz

LocalDSs

• 8 DS freqs

• 3 US freqs

• 5x5 domain



• Pros Four bonding freqs / e-qam connector One e-qam connector per 2 nodes Basic = 5 DS/2 nodes with DCC support US load balance of 2.0 CMs One US connector shared across 2 nodes

for diminishing D1.x CMs

• Cons Requires M-CMTS architecture Requires five DS & three US freqs Must push 3.0 CMs to remote DS Four e-qam connectors and 16 e-qam chs

per 8 nodes

P PP P Basic

Extended

603

609

615

621

32


22

Frequency

ATDMA

ATDMA

627

37 TDMA

P

P

P

P

P

P

P

P

P

P

P

P

P

P

P

P

3.2 MHz

6.4 MHz

RemoteDSs

LocalDSs

• 5 DS freqs

• 3 US freqs

• 5x5 domain


• Frequency assignmentsCMTS may be limited to 860 MHz or 1 GHz

Legacy CMs (1.x & 2.0) limited to 860 MHz bandedge

E-qam limited to contiguous 24 MHz or 4 channel slots

Annex A may only be 3 chs vs 4 for annex B

CMs may be limited to 50 or 60 MHz passband

• M-CMTS architecture requires DTI and local USsDistance limitation, time offset differences, level differences

• Resiliency is another topic to addressIf one DS frequency goes bad in the field, how will CMs recover or

react?


• E-qam licensing?

• CM requires 1.1 config file

• More DS = more US

• Testing and maintaining multiple DS channelsPhysical chs have not changed for DOCSIS 3.0

Test equip with built-in CMs need to support bonding

• DS ch bonding max power with 4 freqs stackedFour chs stacked on 1 connector limited to 52 dBmV/ch

DOCSIS 1.x/2.0 DS is 61 dBmV max output

• DS isolation issues


DS Combiner

DS Splitter

Requires:

• 5 DS freqs

• 3 US freqs in each node

DSs 0-3 = 603 MHzE-QAM = 609, 615,

621, & 627 MHz

DS Tx

Potential Isolation Path

DS0

U0U1U2U3

1x4

DS1

U0U1U2U3

1x4

DS2

U0U1U2U3

1x4

DS3

U0U1U2U3

1x4

Edge-QAM

61?

52?Isolation amp


• Can this device handle 50 dBmV inputs?

W


• D3.0 spec goes to 1 GHz, some equipment may notSA DPC2505 speced to 930 MHz

• DPC2505, 3 ch CM needs all 3 DSs for 111 MbpsCan do annex B &/or A; but requires more spectrum

• D3.0 CM spec requires 60 MHz capture window

• DPC3000 capture of 96 MHz over most spectrum82 MHz max window supported over entire spectrum

• TI 4x4 CM (60 MHz window)

• Brcm 8x4 CM (2, 32 MHz bands or 1, 96 MHz band)DS freqs must be contiguous within tuner block unlike 4x4 CMs

Can use RCC templates to setup both tuners

New feature called Split Tuner will analyze RCC & create 2 Rx modules and move tuners automatically without RCC templates


• Restrict legacy eMTAs to Local DS

• Enforce legacy CMs to only register on Primary-only DS

• Enforce legacy CMs to move to specific DS freq

• Force 3.0-capable CMs to initialize on bonding capable primary DS

• Can specify UCDs sent for each DS

• Put voice call service flows on a primary DScable docsis30-voice downstream req-attr-mask 0 forb-attr-mask

80000000

EDCS-668028 explains this feature


• 2x4 domain appears as 2, 1x2 domains

DS0

U0

U1U2

U3

1x4

Edge-QAM


• Cost effective and faster time to marketDecrease DS costs – deploy D3.0 later with no additional CMTS

investment!

• Targeted insertion of D3.0 Leverage existing US chs while adding more DS capacity

Load balance 1.x/2.0 and enable D3.0 when needed

Minimizes capex & opex

• Leverage D3.0 bonding for D2.0 tiers & services Better stat-mux efficiency & improved consumer experience


• Long term D3.0 service planning Insure optimized frequency allocation

• Enable seamless upgrade to higher D3.0 tiersWire once & add QAM chs as tiers or service take-rates go up

• End-to-end solution minimizes riskCMTS, QAM, and CPE

• Can also disable DS bondingNo cable mrc-mode

Per-CM exclude with vendor specific MIB or TLV

Documents

DOCSIS 3.0 DS Planning & Bandwidth Management John Downey, Consulting Network Engineer – CMTS BU