Embodiments of the present invention disclose a peripheral component interconnect express interface control unit. The unit includes a P2P module, configured to receive a first TLP from a RC or an EP and forward the first TLP to a reliable TLP transmission RTT module for processing. A reliable TLP transmission module is configured to determine, according to the received first TLP, sending links connected to active and standby PCIE switching units, and send the first TLP to the active and standby PCIE switching units through the sending links at the same time. A destination PCIE interface controller of the first TLP selectively receives the first TLP forwarded by the active and standby PCIE switching units and sends the first TLP to a destination EP or a destination RC. Thereby, reliable transmission of a TLP is implemented in a case of a PCIE switching dual-plane networking connection.