25-3
Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 25 Configuring SONET Automatic Protection System
Tiered Management Control
Figure 25-1 SONET Section, Line, and Path
Table 25-3 provides a cross-reference between OC-
n
optical carrier levels, the equivalent STS-
n
and
SDH-
n
levels, and the associated line rates.
Manual Operation
SONET Automatic Protection Switching configures a pair of SONET lines for line redundancy so that
the interface hardware automatically switches from a working line to the protection line or vice versa
within a specified period after an active line failure.
However, you may use the
switchapsln
command to manually control switching. The last user switch
request (
switchapsln
) per line pair is saved by switch software so that the APS can be configured
correctly in the event of a node rebuild.
Table 25-2 SONET Section, Line, and Path Descriptions
Unit
Description
Section
A section is the fiber optic cable between two active elements such as simple
repeaters. The active element terminating these sections is called Section
Terminating Equipment (STE).
Line
A line is a physical element that contains multiple sections and repeaters and is
terminated by line terminating equipment (LTE) at each end.
Path
A path includes sections and lines and terminates at the customer premises
equipment (CPE).
Section
CPE
CPE
Switch
LTE
Switch
LTE
STE
STE
Section
Line
Path
12196
Section
Table 25-3 Digital Hierarchies
OC-n
Optical Carrier
STS-n
Synchronized
Transport Signal
Line Rates (Mbps)
SDH-n
Synchronized
Digital Hierarchy
STM-n
Synchronous
Transport Module
OC-1
STS-1
51.84
OC-3
STS-3
155.52
SDH-1
STM-1
OC-12
STS-12
622.08
SDH-4
STM-4
OC-48
STS-48
2488.32
SDH-16
STM-12
Содержание BPX 8650
Страница 49: ...P A R T 1 The BPX Switch ...
Страница 50: ......
Страница 159: ...P A R T 2 Installation ...
Страница 160: ......
Страница 273: ...P A R T 3 Initial Configuration and Network Management ...
Страница 274: ......
Страница 311: ...P A R T 4 Configuring Connections ...
Страница 312: ......
Страница 487: ...P A R T 5 Troubleshooting and Maintenance ...
Страница 488: ......
Страница 533: ...P A R T 6 BPX Specifications ...
Страница 534: ......
Страница 555: ...P A R T 7 Appendices ...
Страница 556: ......