RFC 4863:Wildcard Pseudowire Type
RFC-Ref

Unidirectional


Click on the red underlined text to get to the source

... PW endpoint must initiate the creation of a unidirectional LSP. ...
... CONTROL], both Label Mapping messages must carry the PW type, and the two unidirectional mapping messages must be in agreement. Thus within the current procedures, the PW ...
... in order to learn the PW Type, prior to signaling its unidirectional LSP. ...



Google
Web
RFC-Ref