Optical Transport Network (OTN) elements
This section includes a summary table with the key elements in the ENP model related to Optical Transport Networks (OTN). Links to the Javadoc are included, of interest to those developing ENP applications or ad-hoc modules.
| Class | Name | Description |
|---|---|---|
| AbstractUnidiLinkWithSubpaths | Unidirectional link with subpaths | This element represents an abstract ENP port-based point-to-point connection, with the possibility of being realized via one or more paths (or subpaths), for example, in 1+1 arrangements, providing common information and behavior for all elements of this type. |
| AbstractUnidiSubpath | Abstract unidirectional subpath | This element represents an abstract ENP point-to-point connection that is a path (or subpath) of another connection, providing common information and behavior for all elements of this type. For example, an OTU connection can be realized by one or more OTU subpaths (e.g., in 1+1 arrangements), each of them being elements of this type. |
| OchType | OCh configuration setting | This class represents an OCh configuration option: modulation, tunability range of the optical signal, spectrum mask, rate, nominal reach, tolerances at reception for power, chromatic and polarization mode dispersion, or OSRN, and other physical characteristics. |
| OtuTopologyDesignRule | OTU topology constraint | This element represents a user-defined constraint to apply to the OTU topology of the network. It permits the user to limit how many OTU-capable nodes (capable of starting/ending OTUs) with particular tags can have OTUs (outgoing to and/or incoming from) with nodes with other particular tags. This flexible scheme offers the user the possibility to enforce practical OTU topology rules, coming from operational considerations, in the OTU-topology designs. For instance, making nodes of a given user-defined type (e.g., edge nodes) to connect to at least two other nodes of another user-defined type (e.g., core nodes), to enforce an internal user policy. |
| UnidiEthernetLink | Unidirectional Ethernet link | This element represents a unidirectional Ethernet link between two end Ethernet ports of the same or different nodes. |
| UnidiOch | Unidirectional OCh | This element represents a unidirectional OCh (Optical Channel) between two OCh ports of the same or different end nodes. An OCh is part of an OTU path (OTU, Optical Transport Unit). OChs are not created by the user directly, but indirectly via the creation of OTUs. An OCh can be realized by one or two (1+1) OCh paths. Each OCh path traverses a sequence of WDM links and/or fiber spans (Optical Transmission Sections, OTSs) from the OCh origin port to the OCh end port. |
| UnidiOdu | Unidirectional ODU | This element represents a unidirectional ODU (Optical Data Unit) that satisfies a particular ODU request. An ODU starts and ends in ODU ports of the ODU request end nodes and has the rate indicated in the request it satisfied. ODUs can be realized by one or two (1+1) ODU paths. Each ODU path traverses a sequence of OTUs (OTU, Optical Transport Unit) from the ODU start port to the ODU end port. |
| UnidiOduRequest | Unidirectional ODU request | This element represents a request for a unidirectional ODU (Optical Data Unit) of a particular rate between two particular end nodes. This request can be realized with an ODU. |
| UnidiOts | Unidirectional OTS (fiber span) | This element represents a unidirectional Optical Transmission Section (OTS) link between two end OTS ports, belonging to the same or different nodes. An OTS can be part of WDM links or not. In the latter case, they are typically used for connecting nodes inside a site. |
| UnidiOtu | Unidirectional OTU | This element represents a unidirectional OTU (Optical Transport Unit) between two end OTU ports, belonging or not to the same node. An OTU can be realized by one or two (1+1) OTU paths. Each OTU path traverses a sequence of OChs, and OEO regeneration is implemented in intermediate nodes between consecutive OChs. |
| UnidiSubpathOch | Unidirectional path of an OCh | This element represents a unidirectional Optical Channel (OCh) path, realizing an OCh. In 1+1 OChs, two paths realize the OCh, one tagged as main and the other as backup. OCh paths are characterized by the sequence of WDM and/or OTS links traversed. The first link starts in the same port group as the origin port of the OCh, the last link ends in the same port group as the end port group of the OCh. |
| UnidiSubpathOdu | Unidirectional path of an ODU | This element represents a unidirectional Optical Data Unit (ODU) path, realizing an ODU. In 1+1 ODUs, two paths realize the ODU, one tagged as main and the other as backup. ODU paths are characterized by the sequence of OTUs traversed. The first link starts in the same port group as the origin port of the ODU, the last link ends in the same port group as the end port group of the ODU. |
| UnidiSubpathOtu | Unidirectional path of an OTU | This element represents a unidirectional Optical Transport Unit (OTU) path, realizing an OTU. In 1+1 OTUs, two paths realize the OTU, one tagged as main and the other as backup. OTU paths are characterized by the sequence of OChs traversed. The first link starts in the same port group as the origin port of the OTU, the last link ends in the same port group as the end port group of the OTU. |
| UnidiSubpathWdm | Unidirectional path of a WDM link | This element represents a unidirectional Wavelength Division Multiplexing (WDM) link path, realizing a WDM link. In 1+1 WDM links, two paths realize the link, one tagged as main and the other as backup. WDM link paths are characterized by the sequence of fiber spans (OTS, Optical Transmission Section) traversed. The first OTS starts in the same port group as the origin port of the WDM link, the last OTS ends in the same port group as the end port group of the WDM link. |
| UnidiVirtuallyTransportedLink | Unidirectional virtual transport connection | This element represents a unidirectional Virtual Transport connection link between two end Virtual Transport ports of the same or different nodes. Virtual transport connections are used to connect IP nodes between them when no information is present on the underlying transport technology. These connections are always arranged in bidirectional pairs. |
| UnidiWdm | Unidirectional WDM link | This element represents a unidirectional WDM (Wavelength Division Multiplexing) link between two end WDM ports belonging to the same or different nodes. A WDM can be realized by one or two (1+1) WDM link paths. Each WDM link path traverses a sequence of fiber spans (Optical Transmission Section, OTS), and optical amplification can occur at intermediate nodes (typically called optical line amplifiers). |