OneAccess Crocus CNV, Руководство пользователя и справочник

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Crocus CNV Diagnostic tests
Reference manual 145
11.5.3 Remote digital loop
Initiating the RDL test establishes a digital loop on the remote Crocus CNV. This loop is compliant to loop
2 as described in the ITU-T recommendation V.54.
The loop is situated immediately behind the DTE interface of the remote Crocus CNV, schematically
represented as follows:
An RDL test can be ended by sending a 2^15-1 pattern.
How to use this test?
Example:
Suppose you have a set-up with two Crocus CNVs connected with each other through their onboard
G703 interfaces (i.e. a simple “modem” connection).
Phase Description
1 Start an RDL test on the local Crocus CNV or start a DL test on the remote Crocus CNV.
⇒
A digital loop is established on the remote Crocus CNV.
2 Start an ET test on the local Crocus CNV.
⇒
A test pattern is sent down the line.
3 Because the remote side is in a digital loop, the test pattern returns to the local Crocus
CNV.
4 The detector receives this test pattern, and can compare it with the original transmitted
pattern.
⇒
The quantity of inconsistencies that might exist between the original and the returned
pattern could be an indication of the line quality.
onboard
G703
interface
local Crocus IF CNV
DTE
interface
DTE
interface
remote Crocus IF CNV
onboard
G703
interface