This operation allows an NMS to request a list of the fixed cross-connects for the specified managed element at the specified layer rates.
The operation will also return fixed cross connections between GTPs.

Operation Exceptions:
1. NOT_IMPLEMENTED - Raised when EMS does not support this operation.
2. INTERNAL_ERROR - Raised in case of non-specific EMS internal failure.
3. INVALID_INPUT - Raised when connectionRateList is empty or contains invalid rates.
4. NE_COMM_LOSS - Raised when communication to managed element is lost.
