This operation activates a pending SNC and deactivates an active SNC.
It also applies to bundled SNCs.

Operation Exceptions:
1. NOT_IMPLEMENTED - Raised when the EMS does not provide this operation.
2. INTERNAL_ERROR - Raised in case of non-specific EMS internal failure.
3. INVALID_INPUT - Raised when any input parameter is syntactically incorrect (e.g. SNC names provided do not refer to
    a SNC object, or any field in tpsToModify is invalid).
4. OBJECT_IN_USE - Raised if the SNC can not be activated because of CC or TP conflicts (e.g. because of timeslot
    conflicts) or conflicts between the active route (with equal or higher priority) of this and other SNCs or when CC creation
    would involve a TP that has an existing fixed CC that does not match that required for the SNC.
5. ENTITY_NOT_FOUND - Raised when SNC names or tpsToModify reference an SNC/TP object that does not exist.
6. UNABLE_TO_COMPLY - Raised when the SNC cannot be activated because it cannot comply with any of the input
    parameter constraints for a reason different than the ones above.
    Raised when the EMS is unable to execute the request because at least one of the parameters although valid can not
    be set and that parameter is identified as "not best effort" in the supporting document LayeredParameters.pdf
    associated to the TransmissionParameters object; i.e. the whole operation will be rejected if one parameter fails that
    must be set. This is potentially usable for cases where a parameter must be set for the SNC to be valid.
    If the EMS cannot determine the reason it could not comply, it is also allowed to throw UNABLE_TO_COMPLY. 
7. NOT_IN_VALID_STATE - Raised where the SNC would involve a CTP that is not connectable due to the state of the
    server TP or in the case of inverse multiplexing where the SNC would involve a CTP that is not connectable due to the
    state of the client TP.
8. NE_COMM_LOSS - Raised when communication to managed element is lost and this prevents any change to the SNCs.
