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Cisco 12000/10700 v3.1.1 Router Manager User Guide
OL-4455-01
APPENDIX

A

SONET/SDH Conversio n Chart

The term Sync hrono us Optical N ETwork (SONET ) is used instea d of Synchron ous Digita l Hierarc hy
(SDH) thro ughout th is Guide. H owever, these two term s are somewhat interc hangeabl e. The
Cisco 12000/10720 Router Manager application handles both SDH and SONET in the same manner . The
Cisco 12000 Series Routers support bot h SDH and SONET.
SONET was defined by the American National Standards Institution (ANSI) and is used in North
America.
SDH was defined by the European Telecommunications Standards Institute (ETSI) and is now used
everywhere ou tside of Nor th Ame rica and Ja pan. SD H was st anda rdiz ed by the Inte rn ationa l
Telecommunications Union (ITU).
Table A-1 compares SONET and SDH speeds.
Table A-1 SONET and SDH Speeds
SONET SDH
OC-3 STM-1
OC-12 STM-4
OC-48 STM-16
OC-192 STM-64