A network linking device in communication with a computer host and an external network is disclosed. The network linking device includes a media access controller (MAC), a buffer and a feature value evaluator. The MAC in communication with the external network receives a data packet from the external network, and stores the data packet in the buffer in communication therewith. The feature value evaluator in communication with the buffer determines whether the data packet complies with a transfer condition according to a feature value included in the data packet, and actuates the MAC to assert an interrupt signal to the computer host when the feature value indicates the data packet complies with the transfer condition. A method for transferring a data packet between a computer host and an external network is also disclosed.