* 16 channel dvr * Support NTSC & PAL Standards * Embedded Linux operating system * User friendly graphic menu * Built-In Multiplexer * Quadruplex function - simultaneous record / playback / network / backup * Recording compression method: MPEG-4 * Network transmission method: MPEG-4 / M-JPEG selectable * Real-time live display & recording per channel * Up to 480pps recording @ D1 (720 x 480) resolution * Multiple main video outputs: 4 composite, 1 VGA * Hidden / Covert camera function * Built-in backup device: DVD-RW * External backup device support: USB Thumbdrive * Internal storage bays: (4) 2 internal & 2 removable * Expandable storage: Support up to 8 AP-ES units * Mirror recording * Mini player: auto installation into DVD during backup * Watch dog / power failure recovery * RS-422/485 for PTZ speed dome and keypad controller (NVCK-3X) * Support various PTZ protocols * Time synchronization between multiple DVRs * 4 Channel audio with 2-way audio over network * Firmware upgrade via USB or network * IR remote controller * Optional SDK available for large integration support * Proprietary Dynamic DNS Service for Plug-n-Play Remote Connection