Config File from scratch |

You are here

Config File from scratch

9 posts / 0 new
Last post
Config File from scratch

Hi! Iam new to docsis, and I barely understand how a CMTS works, and I need to know how to make a basic configuration file for a cable modem, and what parameters that i need to consider when making a configuration file, i hope you can help me with it.


There is a lot of unknowns to

There is a lot of unknowns to this question

What version of Docsis are you targeting? docsis 1.0 or docsis1.1+

assuming Docsis1.1+ (including docsis 2.0 and 3.0)
Are you going to include all the params for the service flows in the config or in the CMTS using service class Names

Assuming Service class names its much simpler (in docsis sourceforge project format)

NetworkAccess 1;
MaxCPE 3;
GlobalPrivacyEnable 1;
AuthTimeout 10;
ReAuthTimeout 10;
AuthGraceTime 600;
OperTimeout 10;
ReKeyTimeout 10;
TEKGraceTime 600;
AuthRejectTimeout 60;
SAMapWaitTimeout 1;
SAMapMaxRetries 4;
UsServiceFlowRef 1;
QosParamSetType 7;
ServiceClassName "USFLOW_NAME";
DsServiceFlowRef 101;
QosParamSetType 7;
ServiceClassName "DSFLOW_NAME";

then in your CMTS you would need some thing like this (assuming cisco)

cable service class 1 name USFLOW_NAME
cable service class 1 upstream
cable service class 1 sched-type 2
cable service class 1 req-trans-policy 8A
cable service class 1 max-rate 256000
cable service class 1 priority 1

cable service class 2 name D_HS1
cable service class 2 downstream
cable service class 2 max-rate 1000000
cable service class 2 max-burst 3044
cable service class 2 priority 1

The advantage being if you change the speeds, you edit the config on the CMTS and the next time the modem dhcps it will get the new speed as opposed to having to edit potentially 100s of configs individually.

what models of modems are you going to support? Are you going to do Firmware upgrades?

the list goes on and on.

The best config generator I have seen is the one from Arris called PacketAce, it requires a support contract with them but includes dozens of example configs to compare and contrast. caveat it can only work with configs for arris modems, i.e. can't edit files with non-arris CVCs.

In my setup we have approx 15 service levels (residential and commercial) and we support firmware updates on 25-30 models of modems, this translates into 500-1000 different config files (I do different configs for each docsis version too, which is mostly unnecessary) Since it quickly got unweildly to hand edit hundreds of files any time there was a change i wrote a script that automated the config file building process. Depending on your needs this may or may not be necessary.

Thank you...

yes i am doing it for docsis 1.1+ and so on,

i am using cisco Ubr7246, and i want to target cisco modems as well as Inovo modems,

i am now studying to apply service class to the CMTS, and thank you for your help, this is exactly what i need,

however i still have questions, is it the cable service class name i need to declare to the CMTS and CM file or the service class number or both? because what i want to have is that the CM file will only contain the names of the packages and i will put all parameters (speed, burst, priority, etc.).

And also, how will i add traffic shaping to the packages?

Service class name only, all

Service class name only, all the other params can be put in the cmts.

traffic shaping is done on the router, not the cm's.

rate limiting

thanks for the reply, what i mean is, rate limiting. the cmts will have a policy on excessive downloading of cpe. If the CPE exceeds the allowable time in downloading the bandwith will drop off significantly in a matter of time, after the penalty, the bandwith will back to normal.

do a search on these forums

do a search on these forums for power boost there are several examples of how to do it. Though it works a little differently than you describe, customer is allocated a higher bandwidth until they use a predefined amount then there speed goes back to normal and the speed boost recharges.

Or if you want to do what you describe you can use cisco's subscriber traffic management but it is more of a peak/off peak type of monitor.


yes that i will do, i appreciate your help.. thanks a lot!

Have a look at:http://www

thanks, I appreciate it,

Log in or register to post comments