Paradyne COMSPHERE
3610, Руководство оператора

Страница: 29 / 310

Introduction
1-13 3610-A2-GB91-90 July 1999
•
Point-to-Point Circuit
With this technique, the control DSU uses a Time
Division Multiplexing (TDM) method to allocate a
portion of the total bandwidth for the in-band
secondary channel transport. It can be used for
point-to-point circuits in both single port and TDM
configurations.
You must specify the DDS network line speed and
the DTE port speed. Note that if there is no excess
bandwidth, you must specify the in-band secondary
channel transport speed. In this case, the DSU
reduces the data clock based upon your selection.
To specify the in-band secondary channel transport
speed, use the configuration option 2nd Ch(bps)
(In-band Secondary Channel Transport Speed) as
shown in
Tables 6-6 and 6-7 , Diagnostic DSU and
DBM Configuration Options, respectively, in
Chapter 6 of this guide.
•
Multipoint Circuit
A multipoint circuit uses two different techniques
for diagnostic transport: one for upstream and one
for downstream.
For downstream diagnostics, the DSU uses a TDM
method to allocate a portion of the total bandwidth
for the in-band secondary channel transport. You
must specify the DDS network line speed and the
DTE port speed. Note that if there is no excess
bandwidth, you must specify the in-band secondary
channel transport speed. In this case, the DSU
reduces the data clock based on your entry. To
specify the in-band secondary channel transport
speed, use the configuration option 2nd Ch(bps)
(
Tables 6-6 and 6-7 , Diagnostic DSU and DBM
Configuration Options, respectively).
NOTE
In DP I I protocol, the Tributary
Time-out alarm is mapped into
the NoResponse alarm.
For upstream diagnostics, the DSU relies on the
primary channel protocol. The tributary DTEs in a
multipoint network are sequentially polled by the
control DTE, and each tributary responds one at a
time with data.
When a tributary DTE raises RTS, no other DTE
should be transmitting. The tributary DSU sends a
few bytes of diagnostic data upstream before
raising CTS to the tributary DTE. Once this is done,
the tributary DSU transmits primary data upstream.
The control DSU maintains a timer for each
tributary DSU. If a tributary DSU does not provide
a health and status update before the timer expires,
the control DSU reports a Tributary Time-out
alarm for the tributary. The duration for the timer is
set using the configuration option TribTimOut
(refer to Table 6-8,
Diagnostic General
Configuration Options ). The Tributary Time-out
alarm can be triggered by a Facility Alarm, a DSU
Alarm, or a remote DTE Alarm (DTE does not
respond to polls).
Using this technique for a multipoint circuit causes
the downstream data rate to be lower than the
upstream data rate. If this is not acceptable, enable
the configuration option M-PtSymPrt (Multipoint
Symmetrical Port) for all controls and tributaries so
that the upstream and downstream data rates match.
(Refer to Table 6-8,
Diagnostic General
Configuration Options , in Chapter 6 for further
information.)
•
Multichannel Multipoint (MCMP)
For MCMP nondisruptive diagnostics, built-in
in-band secondary channel transport is provided;
you do not need to reduce the bandwidth. The Diag
Type (Diagnostic Type) configuration option should
be set to NonD.
NOTE
Diagnostic types and in-band
secondary channel transport
speeds must be set to the same
value for both the control and the
tributary DSUs. If these
configuration options are set to
different values and
communication to the tributary is
lost, reconfigure the control for
disruptive diagnostics and
reconfigure the tributary, as
required.