[en] The ATLAS readout subsystem is the main interface between ∼ 1600 detector front-end readout links and the higher-level trigger farms. To handle the high event rate (up to 100 kHz) and bandwidth (up to 160 MB/s per link) the readout PCs are equipped with four ROBIN (readout buffer input) cards. Each ROBIN attaches to three optical links, provides local event buffering for approximately 300 ms and communicates with the higher-level trigger system for data and delete requests. According to the ATLAS baseline architecture this communication runs via the PCI bus of the host PC. In addition, each ROBIN provides a private Gigabit Ethernet port which can be used for the same purpose. Operational monitoring is performed via PCI. This paper presents a summary of the ROBIN hardware and software together with measurements results obtained from various test setups