OTN Functional Architecture

Bearing in mind the goals of the OTH initiative, we can begin to visualize the structure and purpose of the OTN system. It would be predominantly optical delivery, certainly in its transmission path as it would be deployed over WDM. It would also retain one of WDM's advantages that of frame, protocol and bit-rate transparency independently of the client signals processing and transmission. Furthermore, we can see that the OTN model will have to provide telecommunications network management, monitoring and administrative control. Last, but not least, the OTN will provide necessary fault-tolerance, by providing protection mechanisms and link fail-over for redundancy.  

Therefore, the OTN must deliver the following functions on a per-client signal basis:  

•Transport 

•Routing 

•Multiplexing 

•Supervision 

•Survivability