Juniper JUNOSE 10.0.X PHYSICAL LAYER, Руководство по настройке

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Figure 8: Stack for cOCx/STMx Interfaces
NOTE: For a detailed description of interface types and specifiers, see Interface Types
and Specifiers in JUNOSe Command Reference Guide . For information about interfaces,
see Planning Your Network in JUNOSe System Basics Configuration Guide .
The section layer manages the transport of STS/STM frames across the physical path.
This layer is responsible for frame alignment, scrambling, error detection, error
monitoring, signal reception, and signal regeneration.
The line layer manages the transport of SONET/SDH payloads, which are embedded
in a sequence of STS/STM frames in the physical medium. This layer is responsible
for multiplexing and synchronization.
The path layer maps the user payload into a SONET/SDH format suitable for the line
layer. This layer transports the actual network services (such as T1s and T3s) between
SONET/SDH multiplexing devices and provides end-to-end transmission.
When you configure a cOCx/STMx interface, be sure you understand its position in
the SONET or SDH hierarchy. This implementation of SONET and SDH uses the term
path to identify an STS-1 or STM-1 line. You must know how to identify the path for
the configuration and the higher-level controllers , such as T3 or unframed E1 over
SONET VT.
SONET/SDH VT Controllers
SONET/SDH VT on cOCx/STMx interfaces support these options:
■
A fractional T1 or E1 line
You assign channel groups of timeslots to configure fractional T1 or E1 over
SONET/SDH VT on cOCx/STMx interfaces. A channel group is the fraction of the
T1 or E1 line and comprises up to 24 T1 timeslots or up to 31 E1 timeslots. The
default channel group speed for both T1 and E1 is 64 Kbps; 56 Kbps is also
available.
■
An unframed E1 line
Platform Considerations
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Chapter 4: Configuring Channelized OCx/STMx Interfaces