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Chapter 9
Measure Mode – Service Tab
DOCSIS
DSAM Help User Guide
Rev. 001
211
Step 4
During step 4 of the DOCSIS Test process, DSAM establishes regis-
tration activities for the cable modem as defined by the DOCSIS spec-
ification and displays the following text next to the third box:
– Connecting to DHCP server
– Connected to DHCP server
– Registering with CMTS
– Connecting to TFTP server
– Connected to TFTP server
Understanding
Range Results
The DOCSIS screen displays resulting ranging and displays measure-
ment performance data on the upstream and downstream signal level,
downstream modulation error ratio (MER) or EVM, as configured, and
the estimated downstream bit error rate (BER) before and after
forward error correction (FEC).
You can view the range measurement data in relation to user-config-
ured limits to determine the pass/fail status of the DOCSIS channel.
Values are continuously updated.
Only valid measurements and parameters appear. When incomplete
measurements occur due to system errors or a manual termination of
the measurement procedure, dashes (---) appear instead of invalid
numeric values. When limit test results are incomplete, a question
mark (?) is displayed.
Measurement
Information Area
The overall pass/fail result is displayed in the top left corner next to the
selected limit set. The failure of any one item produces an overall
failure.
Figure 190
Measure Mode – DOCSIS
Measurement
Information Area
Test Complete Results
Downstream/Upstream
Pass/Fail Results
MER Headroom
LEVEL Headroom
High Sensitivity Mode
21128026 R001 DSAM Help User Guide.book Page 211 Thursday, February 5, 2009 2:02 PM