 EnasYorlThieves World
join:2001-12-02
West
4 edits | reply to netcool
Re: Technical Discussion of Upstream Channel Bondingsaid by netcool:said by EnasYorl:So in short maybe it can be done in a lab (I've yet to see anyone show it done), but I would bet money that no one bonds those different modulation schemes in the real world deployment.
You would lose that bet. Look through this thread, many many people have bonded channels using different modulation profiles. I myself have two channels bonded, one TDMA and one ATDMA. It also helps that I can login to the CMTS to verify as well ;) So in GW, CO you are saying your bonding 1.1 and 2.0 upstreams? Care to show your modem? DownstreamBonding Channel Value
Channel ID101 102 103 104
Frequency567000000 Hz 573000000 Hz 579000000 Hz 585000000 Hz
Signal to Noise Ratio35 dB 35 dB 35 dB 35 dB
Downstream ModulationQAM256 QAM256 QAM256 QAM256
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
-3 dBmV -3 dBmV -4 dBmV -4 dBmV
UpstreamBonding Channel Value
Channel ID4 3
Frequency22800000 Hz 32400000 Hz
Ranging Service ID7409 7409
Symbol Rate5.120 Msym/sec 5.120 Msym/sec
Power Level49 dBmV 49 dBmV
Upstream Modulation[3] QPSK
[3] 64QAM
[3] QPSK
[3] 64QAM
Ranging StatusSuccess Success
Signal Stats (Codewords)Bonding Channel Value
Channel ID101 102 103 104
Total Unerrored Codewords197599661448 25800590019 25800424592 25800201713
Total Correctable Codewords2663474 3045577 3211190 3432391
Total Uncorrectable Codewords2718 2495 2439 1619
Now looking at this data from my two upsteams what modulation is Really in use QPSK or 64 QAM? is the Modem accurate with it's data or is it false? I can tell you for a long time I had both carriers present but they were not bonded until recently as my modem is one of the few that will indicate true bonding. Upstream Bonding Channel Value Channel ID 4 3 Frequency 22800000 Hz 32400000 Hz Ranging Service ID 7409 7409 Symbol Rate 5.120 Msym/sec 5.120 Msym/sec Power Level 49 dBmV 49 dBmV Upstream Modulation [3] QPSK [3] 64QAM [3] QPSK [3] 64QAM I will throw in the CMTS command info as well cable upstream docsis-mode
To configure an upstream to use DOCSIS 1.x, DOCSIS 2.0 or DOCSIS 3.0 modulation profiles, use the cable upstream docsis-mode command in cable interface configuration mode. To reset the upstream to its default configuration, use the no form of this command.
cable upstream n docsis-mode {atdma | scdma | scdma-d3 | tdma | tdma-atdma}
no cable upstream n docsis-mode {atdma | scdma | scdma-d3 | tdma | tdma-atdma}
Syntax Description
n
Specifies the upstream port. Valid values start with 0 for the first upstream port on the cable interface line card.
atdma
Configures the upstream only for DOCSIS 2.0 Advanced Time Division Multiple Access (A-TDMA) modulation profiles.
scdma
Configures the upstream for DOCSIS 2.0 Synchronous Code Division Multiple Access (S-CDMA) modulation profiles only.
scdma-d3
Configures the upstream for DOCSIS 3.0 S-CDMA modulation profiles. The scdma-d3 option uses channel type 4SR mode.
tdma
Configures the upstream only for DOCSIS 1.0/DOCSIS 1.1 Time Division Multiple Access (TDMA) modulation profiles (default).
tdma-atdma
Configures the upstream for both A-TDMA and TDMA operations (mixed mode). If you are using abbreviations at the command line, you must specify at least the tdma to select the mixed mode. If you choose a shorter abbreviation, you select TDMA-only mode.
Command Default
All upstreams are configured TDMA-only mode (DOCSIS 1.0/DOCSIS 1.1).
Command Modes
Interface configuration (config-if)
Command History
Release
Modification
12.2(15)CX
This command was introduced to support DOCSIS 2.0 A-TDMA and mixed modulation profiles on the Cisco uBR-MC16U/X and Cisco uBR-MC28U/X cable interface line card on the Cisco uBR7246VXR router.
12.2(15)BC2
Support was added for the Cisco uBR-MC5X20S/U cable interface line cards on the Cisco uBR10012 router.
12.3BC
This command was integrated into Cisco IOS Release 12.3BC.
12.2(33)SCA
This command was integrated into Cisco IOS Release 12.2(33)SCA.
12.2(33)SCC
This command was modified with the addition of scdma and scdma-d3 keyword options and support was added for the Cisco UBR-MC20X20V cable interface line card on the Cisco uBR10012 router.
Usage Guidelines
The DOCSIS 2.0 specification builds on the existing TDMA to support advanced modulation profiles that increase potential upstream bandwidth. The A-TDMA profiles support higher QAM rates of up to 64-QAM and wider channel widths of up to 6.4 MHz (5.12 Msymbols).
NoteThe advanced hardware-based spectrum management features for the Cisco uBR-MC16S/U/X, Cisco uBR-MC28U/X, and Cisco uBR-MC5X20S/U cards are supported only in the DOCSIS 1.0/1.1 TDMA-only mode. They cannot be used in the mixed or A-TDMA-only modes.
The DOCSIS 2.0 specification allows an upstream to be configured in one of the following three modes:
•A-TDMA only mode—Upstreams only support cable modems that register using A-TDMA modulation profiles. The CMTS does not allow DOCSIS 1.0 and DOCSIS 1.1 cable modems to register and come online on these upstreams. The Cisco uBR-MC5X20S/U, Cisco uBR-MC16U/X, and Cisco uBR-MC28U/X cards also support 6,400,000 Hz (5,120,000 symbols/sec) when operating in DOCSIS 2.0 (A-TDMA-only) mode.
Changing the DOCSIS mode to A-TDMA only mode automatically changes the symbol rate to 5.12 megasymbols per second and the channel width to 6.4 MHz. It also automatically disables the dynamic upstream modulation.
In addition, the following are required to support the DOCSIS 2.0 A-TDMA features:
–Cable modems must be DOCSIS 2.0 compliant.
–The DOCSIS configuration file for the cable modem must either omit the DOCSIS 2.0 Enable field (TLV 39), or it must set TLV 39 to 1 (enable). If you set TLV 39 to 0 (disable), a DOCSIS 2.0 CM uses the TDMA mode.
–The upstream must be configured for either A-TDMA-only or mixed TDMA/A-TDMA mode.
•TDMA-only mode—Upstreams only support cable modems that register using TDMA modulation profiles. DOCSIS 2.0 cable modems can register on these upstreams only by using a DOCSIS 1.0/DOCSIS 1.1 modulation profile (which typically would happen only when a DOCSIS 2.0 cable modem cannot find an A-TDMA channel in its DOCSIS domain).
Changing the DOCSIS mode to TDMA-only mode automatically changes the symbol rate to 1.28 megasymbols per second and the channel width to 3.2 MHz. It also automatically disables the dynamic upstream modulation.
•Mixed mode—Upstreams support both DOCSIS 1.0/DOCSIS 1.1 cable modems using TDMA modulation profiles and DOCSIS 2.0 cable modems using A-TDMA modulation profiles. (The maximum channel width in mixed mode is 3.2 MHz.)
Changing the DOCSIS mode to mixed mode also automatically changes the symbol rate to 1.28 megasymbols per second and the channel width to 3.2 MHz. Dynamic upstream modulation is also automatically disabled.
NoteMixed mode upstreams do not support the 6.4 MHz channel width.
The DOCSIS 3.0 specification allows an upstream to be configured in one of the following modes:
•SCDMA-d3 mode—Upstreams only support cable modems that register using DOCSIS 3.0 S-CDMA modulation profiles.
•SCDMA mode—Upstreams only support cable modems that register using DOCSIS 2.0 S-CDMA modulation profiles.
NoteThe DOCSIS 3.0 option scdma-d3 (4SR) is available only when the CMTS is configured to operate in the global modulation profile format and is not available in the default mode. This option is available only for the Cisco UBR-MC20X20V cable interface line card, and not for other legacy line cards.
Refer to the cable upstream channel-width command for valid values of supported channel widths and DOCSIS modes for cable interfaces.
http://www.cisco.com/en/US/docs/ios/cable/command/reference/cbl_10_cable_u_to_cable_w.html#wp1090928 Based on the vendor information I don't believe you've proven your point. Especially when scdma-d3 is what is needed to bond. Configures the upstream for DOCSIS 3.0 S-CDMA modulation profiles. The scdma-d3 option uses channel type 4SR mode. |
EnasYorlThieves World
join:2001-12-02
West
2 edits | Your LED's are BLUE or Green on US indicator?
But my point before was a TDMA carrier wouldn't be bonded based on the info I posted. If you are bonding a channel that is meant for 1.1 DOCSIS modems and 3.0 modems seems like a poor design choice the Return spectrum maybe has too much noise to support multiple 64QAM channels . If both your LED's are blue DS and US, i will admit i'm blown away.
For those whom like to read more on settings in CMTS.
cable modulation-profile
To define a modulation profile for use on the router, use the cable modulation-profile command in global configuration mode. To remove the entire modulation profile or to reset a default profile to its default values, use the no form of this command.
DOCSIS 1.0 and 1.1 Mixed Mode:
cable modulation-profile profile {mix | qam-16 | qpsk | robust-mix}
no cable modulation-profile profile {iuc | mix | qam-16 | qpsk | robust-mix}
cable modulation-profile profile iuc fec-tbytes fec-len burst-len guard-t mod scrambler seed diff pre-len last-cw uw-len
DOCSIS 1.x/2.0 Mixed Mode:
cable modulation-profile profile {mix-high | mix-low | mix-mid | mix-qam | qam-16 | qpsk | robust-mix-high | robust-mix-mid | robust-mix-qam}
no cable modulation-profile profile {iuc | mix-high | mix-low | mix-mid | mix-qam | qam-16 | qpsk | robust-mix-high | robust-mix-mid | robust-mix-qam}
cable modulation-profile profile iuc fec-tbytes fec-len burst-len guard-t mod scrambler seed diff pre-len last-cw uw-len
DOCSIS 2.0 A-TDMA Mode:
cable modulation-profile profile {mix-high | mix-low | mix-mid | mix-qam | qam-8 | qam-16 | qam-32 | qam-64 | qpsk | robust-mix-high | robust-mix-low | robust-mix-mid}
no cable modulation-profile profile {iuc | mix-high | mix-low | mix-mid | mix-qam | qam-8 | qam-16 | qam-32 | qam-64 | qpsk | robust-mix-high | robust-mix-low | robust-mix-mid}
cable modulation-profile profile iuc fec-tbytes fec-len burst-len guard-t mod scrambler seed diff pre-len last-cw uw-len
Cisco IOS Release 12.2(33)SCC and Later
DOCSIS 2.0 A-TDMA Mode and DOCSIS 2.0 S-CDMA Mode:
cable modulation-profile profile {mix-high | mix-low | mix-mid | mix-qam | qam-16 | qpsk | robust-mix-high | robust-mix-low | robust-mix-mid}
no cable modulation-profile profile {iuc | mix-high | mix-low | mix-mid | mix-qam | qam-16 | qpsk | robust-mix-high | robust-mix-low | robust-mix-mid}
cable modulation-profile profile iuc fec-tbytes fec-len burst-len guard-t mod scrambler seed diff pre-len last-cw uw-len
Syntax Description
profile
Specifies the modulation profile number. The valid values for the profile number depend on the cable interface being used and the upstream's mode of operation.
See Table 1 for a list of valid ranges based on cable interface and modulation type.
In Cisco IOS Release 12.2(15)CX and later releases, you can create a maximum of 10 profiles for each mode of operation, for a total of 30 profiles. In earlier software releases, you can create a maximum of 8 profiles only for DOCSIS 1.0 and DOCSIS 1.1 mode.
mix
(DOCSIS 1.0 and DOCSIS 1.1 mode only) Creates a default QPSK/16-QAM mix modulation profile where short and long grant bursts are sent using 16-QAM, while request, initial ranging, and station maintenance bursts are sent using QPSK). The burst parameters are set to their default values for each burst type.
mix-high
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 modes only) Creates a default QPSK/64-QAM modulation profile.
mix-low
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 modes only) Creates a default QPSK/16-QAM modulation profile.
mix-mid
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 A-TDMA modes only) Creates a default QPSK/32-QAM modulation profile.
mix-qam
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 A-TDMA modes only) Creates a default 16-QAM/64-QAM modulation profile.
qam-8
(DOCSIS 2.0 A-TDMA mode only) Creates a default 8-QAM modulation profile.
This modulation profile is available in hidden and internal mode only from Cisco IOS Release 12.2(33)SCC onwards.
qam-16
Creates a default 16-QAM modulation profile.
qam-32
(DOCSIS 2.0 A-TDMA mode only) Creates a default 32-QAM modulation profile.
This modulation profile is available in hidden and internal mode only from Cisco IOS Release 12.2(33)SCC onwards.
qam-64
(DOCSIS 2.0 A-TDMA mode only) Creates a default 64-QAM modulation profile.
This modulation profile is available in hidden and internal mode only from Cisco IOS Release 12.2(33)SCC onwards.
qpsk
Creates a default QPSK modulation profile.
robust-mix
(DOCSIS 1.0 and DOCSIS 1.1 mode only) Creates a default QPSK/16-QAM modulation profile with a longer preamble that is more robust and more able to deal with noise on the upstream better than the mix profile.
robust-mix-high
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 A-TDMA modes only) Creates a default QPSK/64-QAM mixed modulation profile with a longer preamble that is more robust and more able to deal with noise on the upstream better than the mix-high profile.
robust-mix-low
(DOCSIS 2.0 A-TDMA mode only) Creates a default QPSK/16-QAM modulation profile with a longer preamble that is more robust and better able to deal with noise on the upstream than the mix-low profile.
robust-mix-mid
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 A-TDMA modes only) Creates a default QPSK/32-QAM modulation profile with a longer preamble that is more robust and better able to deal with noise on the upstream than the mix-mid profile.
robust-mix-qam
(DOCSIS 1.x/2.0 mixed mode only) Creates a default 16-QAM/64-QAM mixed modulation profile with a longer preamble that is more robust and better able to deal with noise on the upstream than the mix-qam profile.
iuc
Interval usage code. Valid entries depend on the mode of operation:
•If the upstream is configured for DOCSIS 1.0 and DOCSIS 1.1 modulation profiles, the valid values are initial, long, request, reqdata, short, or station.
•If the upstream is configured for DOCSIS 1.x and DOCSIS 2.0 mixed modulation profiles, the valid values are a-long, a-short, a-ugs, initial, long, request, reqdata, short, or station.
•If the upstream is configured for DOCSIS 2.0 A-TDMA modulation profiles, the valid values are a-long, a-short, a-ugs, initial, long, request, reqdata, short, or station.
The reqdata burst type is included as a placeholder for scripts that might reference it, but the DOCSIS MAC scheduler on the Cisco CMTS does not use this type of burst.
When you are using the initial and station bursts for DOCSIS 2.0 A-TDMA mode, qam-8, qam-32, and qam-64 modulation profiles are available in hidden mode only.
preamble
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 A-TDMA modes only, for a-long and a-short options) Specifies the preamble format. Valid values are qpsk0 and qpsk1.
rs-interleave-depth
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 A-TDMA modes only, for a-long and a-short options) Specifies the RS interleave depth. The valid range is from 0 to 114.
rs-interleave-block
(DOCSIS 1.x/2.0 mixed and DOCSIS 2.0 A-TDMA modes only, for a-long and a-short options) Specifies the RS interleave block size. The valid range is from 18 to 2048.
fec-tbytes
The number of bytes that can be corrected per FEC code word. For DOCSIS 1.0 and DOCSIS 1.1 mode, valid values are from 0 to 10 (decimal), where 0 means no FEC. For DOCSIS 2.0 A-TDMA mode, the valid values are from 0 to 16 (decimal), where 0 means no FEC.
fec-len
FEC code-word length. Valid values are from 16 to 253.
burst-len
Maximum burst length in minislots. Valid values are from 0 to 255, where 0 means no limit.
guard-t
Guard time in symbols. The time between successive bursts, with a range from 22 to 255. (In Cisco IOS Release 12.2(15)BC2 and earlier releases, the minimum guard time was 0 symbols, but we do not recommend using a guard time smaller than 22 symbols.)
mod
Modulation. Valid entries are 16qam and qpsk for DOCSIS 1.0 and DOCSIS 1.1 upstreams. Valid entries are 8qam, 16qam, 32qam, 64qam, and qpsk for DOCSIS 2.0 upstreams.
The qam-8, qam-32, and qam-64 modulation profiles are available in hidden and internal modes only from Cisco IOS Release 12.2(33)SCC onwards.
scrambler
Enable or disable scrambler. Valid entries are scrambler and no-scrambler.
seed
(Required if scrambler option used) Scrambler seed in hexadecimal format. Valid values are from 0x0 to 0x7FFF.
diff
Enable or disable differential encoding. Valid entries are diff and no-diff.
In DOCSIS 2.0 mode, differential encoding cannot be enabled for the 8-QAM, 32-QAM, and 64-QAM modulations.
The qam-8, qam-32, and qam-64 modulation profiles are available in hidden and internal modes only from Cisco IOS Release 12.2(33)SCC onwards.
pre-len
Preamble length in bits. Valid values are from 2 to 256.
last-cw
Handling of FEC for last code word. Valid entries are fixed for fixed code-word length and shortened for shortened last code word.
uw-len
Upstream unique word length. Enter uw8 for 8-bit unique code words or uw16 for 16-bit unique code words.
Command Default
Modulation profile 1 is defined as a qpsk Time Division Multiple Access (TDMA) profile.
In Cisco IOS Release 12.2(15)CX, Release 12.2(15)BC2 and later releases, additional modulation profiles are defined as the default mixed TDMA/A-TDMA profile and the default Advanced TDMA (A-TDMA) profile. See Table 1 for a list of valid ranges based on cable interface and modulation type.
Command Modes
Global configuration (config)
Command History
http://www.cisco.com/en/US/docs/ios/cable/command/reference/cbl_06_cable_m.html |
