BL-DVR400E/500E/600E series network DVR contains both digital video recorder (DVR) and digital video server (DVS) functions. It is free from PC platform, based on embedded processor and embedded operating system, instead of PC processor and PC operating system. BL-DVR400E/500E/600E network DVR, provides the below function: video signal and audio signal H.264 hardware synchronization compaction, compaction code stream recording hard disc , real time video and audio preview, video signal and audio signal switching, local video recording file playback, real time network transmission, remote file playback and download, support stream protocol (RTP/RTCP, RTSP), support IE browsing, support bidirectional voice talk back, etc. Physical Interface： ˙Up to 16-channel video input； ˙Up to 16-channel audio input； ˙1-channel video output； ˙1-channel audio output; ˙1-channel input for bi-direction voice talk back； ˙one 10M/100M Ethernet interface； ˙Up to 16-channel alarm signal input interface； ˙4-channel alarm signal output； ˙one RS485 interface; ˙one RS485 keyboard interface； ˙one RS232 interface； ˙one USB interface； ˙one VGA interface； ˙adopt 19 inch standard machine case (45cm*45cm*9.5cm) ˙BL-DVR416E inclusive of loop & matrix function； ˙BL-DVR516E inclusive of loop & matrix function； ˙BL-DVR400E、500E、600E have the approx. same function。