This study investigates the achievable secrecy rate of two-way relay-assisted networks. It is assumed that there is no direct link between transceiver ends and the communication is carried out in two hops through the use of multi-antenna relays in the middle of transmission, where the relays employ amplify-and-forward strategies. To increase the bandwidth efficiency, intending nodes exchange their confidential messages in two hops. First, both nodes simultaneously send their messages to the

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... y nodes. Then, throughout the second hop, the relays make use of cooperative beamforming to send their incoming information in such a way that the achievable secrecy sum rate is maximised, considering each node is subject to a minimum secrecy rate constraint. Accordingly, two beamforming strategies, named as null-space beamforming and information leakage alignment beamforming are proposed, where their achievable secrecy sum rates are investigated and compared to existing works addressed in the literature.