Fujitsu Corporation

Naoto Kidoku

Koji Tanonaka

Hiroyuki Suzuki

Motoshi Hamasaki

Toshikazu Magome

A transmission apparatus utilizing an SDH is provided. The transmission apparatus includes a processing unit controlling the transmission apparatus, an SSM extraction unit extracting a first SSM from an input signal, and a selector selecting either of the first SSM and a second SSM set by the processing unit. The transmission apparatus can add an incoming SSM function, for instance, to an external 2 Mbps SSM function in addition to an assumed SSM function. Accordingly, the transmission apparatus can conform to the ITU-T G.781 Recommendation by utilizing a related-art synchronization function.

Transmission apparatus

The invention concerns synchronization equipment; more particularly, the invention is directed to the provision of synchronization equipment which, after simple hardware installation and software setting, establishes a synchronization network with an existing network, SDH elements, etc. that do not support SSMB. The synchronization equipment comprises: a failure detection section for detecting a failure of each of a plurality of timing sources assigned prescribed priorities; a failure monitoring section for monitoring failure detection information from the failure detection section, and for outputting in the event of detection of a timing source failure a timing source switching control signal directing switching to a timing source having the highest priority among the timing sources other than the failure-detected timing source; a timing source selection section for outputting a timing source switching control signal based on the quality of synchronization derived from SSMB information; and a selection section for selecting one or the other of the two timing source switching control signals.

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Kawasaki, Japan

Naoto Kidoku