Juniper JUNOSE 10.0.X PHYSICAL LAYER, Руководство по настройке

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Table 4: MDL and FDL Message Strings and Message Types (continued)
Test Signal
Message Idle Signal
Message Path
Message
Description
Message
String
✓ ✓ ✓
Line identification code lic
– –
✓
Facility identification code pfi
–
✓
– Equipment port number port
✓ ✓ ✓
Unit identification code unit
As long as another message of any type containing the same string is received within
10 seconds, the line module retains the local copy of the message string and resets
the 10-second timer for that string.
For example, if a line module receives an MDL or FDL test signal message containing
an eic string, and then receives an idle signal message within 10 seconds that also
contains an eic string, it retains the local copy of the most recent eic string received
and resets the 10-second timer for that message. However, if 10 seconds pass without
the line module receiving a path identification, test signal, or idle signal message
containing an eic string, the line module erases the local copy of the eic message
string.
For message strings that are unique to a particular message type, the line module
must receive another message of the same type containing this string in order to
retain the local copy of the string and reset the timer. For example, if the line module
receives a test signal message containing a generator string and does not receive
another test signal message within 10 seconds, it will erase the local copy of the
generator string.
Frequency of FDL Path Messages
E-series routers transmit FDL path identifier messages every second. This behavior
complies with the ANSI T1.403 specification (see “References” on page 9 for more
information) and is consistent with the MDL implementation for E-series routers.
Higher-Level Protocols
See ERX Module Guide , Appendix A , Module Protocol Support for information about
the higher-level protocols that channelized T3 interfaces support.
Platform Considerations
You can configure channelized T3 interfaces on the following E-series routers:
■
ERX-1440 router
■
ERX-1410 router
■
ERX-710 router
Platform Considerations
■ 5
Chapter 1: Configuring Channelized T3 Interfaces