Motorola SB5101U User's Guide download pdf (Page 9)

SB5101 Cable Modem Overview

MOTOROLA BCS CONFIDENTIAL Page 9 of 34

The DOCSIS system was developed to enable hardware and systems

interoperability and automated configuration and management. Cable

Modems (CM’s) and Cable Modem Termination Systems (CMTS’s) from

various vendors will operate on the same network, using the common

DOCSIS standards and protocols. In this model, a CM is authorized by

the CMTS for use on the network, and configures itself according to

parameters that are passed to it from the head-end. This sequence of

events will occur automatically in the background, so the user will be

unaware of the activity. The following paragraph describes the process

of how a CM “logs on” to the network.

When the CM is powered on, it follows one of two scenarios. If it is

logging on to the network for the first time (or the data frequency has

been changed), the CM automatically scans the frequency spectrum to

locate the data frequency. If the CM has previously accessed the

network, it will lock onto the data frequency automatically (the previous

session value is stored). Once the CM finds the DOCSIS data signal, it

looks for a message that contains the basic parameters for the upstream

(frequency, modulation, symbol rate, FEC format, etc.). The CM can

then transmit a message to the CMTS requesting additional information

that will enable it to connect to the network. Through a series of

messages and interactions, the CM will establish IP connectivity using

DHCP, (dynamic addressing), and then will receive a configuration file

via TFTP that has additional parameters the CM needs to configure

itself. Once the CM has been configured, it will register with the CMTS

and be authorized for use of the network. If Baseline Privacy has been

enabled, the final step of the initialization is establishing the parameters

to use Baseline Privacy.

Once the CM has been configured and authorized, it can use the

network like any standard Ethernet network device. The Operations

Support System (OSS) software in the CMTS communicates with all the

CMs and has the ability to re-configure them to use different channels,

to change their parameters, and to disable their ability to use the

network.

5 DOCSIS - Overview

Scan for Downstream

Channel

Obtain Upstream

Parameters

Perform Ranging &

Automatic

Adjustments

Establish IP

Connectivity

Sync to Network

Clock

Establish Baseline

Privacy

Transfer Operational

Parameters

1 2 3 4 5 6 7 8 9 10 11 12 13 14 ... 33 34

Comments to this Manuals

No comments

Motorola SB5101U User's Guide Page 9

Comments to this Manuals

Related products and manuals for Networking Motorola SB5101U