Abstract: A filter for filtering messages transmitted by a first signaling point and destined for a second signaling point, where the filter has a receiver connected to the first signaling point by a first external communication channel and receiving the messages thereon. The filter may have processing logic, coupled within the filter to the receiver, receiving the messages from the receiver, and filtering the messages by deleting or ignoring redundant messages transmitted to fill-in or maintain a data link between the signaling points. And, the filter may have a transmitter, coupled within the filter to the processing logic, receiving the filtered messages and transmitting them in a format capable of being processed by the second signaling point, whereby the second signaling point receives substantially fewer messages fill-in or maintenance messages.