Pelco NVR300 Security Camera User Manual


 
76 C611M-C (3/06)
Appendix. Automatic Data Replenishment (ADR)
This appendix provides an overview of the Automatic Data Replenishment technology used by the NVR300. The appendix also provides setup
instructions required for ADR functionality.
ADR OVERVIEW
When the NVR300 is connected to the PelcoNet NET350T transmission system equipped with local storage (CompactFlash card or a microdrive),
ADR ensures video recording by the NVR300 despite temporary network failure or NVR300 downtime.
NOTE: ADR currently is supported only when the type of recording programmed for the NVR300 is continuous recording. ADR is not supported
when the type of recording programmed for the NVR300 is event recording.
Both the NVR300 and the NET350T are able to detect network status changes, that is, the NET350T and the NVR300 are able to detect when the
network becomes unavailable and then available again. Recording occurs independently at both the NET350T and the NVR300 (refer to
Figure 46). The NET350T records video locally to a CompactFlash card or a microdrive. (Note that audio cannot be recorded to the local storage
medium of the NET350T.)
Figure 46. Recording at NET350T and NVR300
When network failure causes a gap in recording at the NVR300 and the network is then restored, the missing data at the NVR300 is copied from
the uncorrupted recording at the NET350T. Consequently, the corrupted recording at the NVR300 is seamlessly repaired resulting in a flawless
NVR300 recording despite the network failure (refer to Figure 47). Note that ADR requires available bandwidth on the network and available
processing power on the NVR300.
Figure 47. Automatic Data Replenishment at NVR300
GENERAL DESCRIPTION
ADR allows continuous recording of video streams on the NVR300 in case of short-to-moderate network outages. In the event of a network
outage, the NVR300 automatically recognizes when the network is re-established, detects which segments of video it is missing from each
PelcoNet NET350, and copies any missing video that exists on the NET350’s CompactFlash onto the NVR300 HDD array. Since ADR relies on the
network environment and the (optional) CompactFlash storage device at the NET350, ADR is subject to the limitations of both.
NVR300
TCP/IP
NETWORK
NET350T WITH
LOCAL STORAGE
NVR300
TCP/IP
NETWORK
NET350T WITH
LOCAL STORAGE
UNCORRUPTED CONTINUOUS
RECORDING AT THE NET350T
CORRUPTED RECORDING CAUSED
BY NETWORK FAILURE
FOOTAGE RECORDED
DURING NETWORK FAILURE
COPY OVER THE NETWORK
TO REPLENISH DATA
REPAIRED FLAWLESS RECORDING