An apparatus to actively monitor a network having a plurality of twisted-pair communication links. The apparatus includes a plurality of amplifiers corresponding, respectively, to the plurality of twisted-pair communication links, each amplifier having a sufficiently high input impedance and common-mode voltage tolerance to non-intrusively copy a data signal transmitted through a corresponding twisted-pair communication link and amplify the copied data signal. The apparatus further includes a plurality of isolation transformers corresponding, respectively, to the plurality of amplifiers, each isolation transformer receiving the amplified, copied data signal from the corresponding amplifier, and outputting a transformed data signal, and a connector receiving the transformed data signals from the plurality of isolation transformers in a pin order corresponding to the plurality of twisted-pair communication links. A protocol analyzer is also provided to receive the transformed data signals via the connector for decoding and monitoring purposes.