186
187
Port number
A sub address set below the IP address to connect
multiple parties simultaneously for communication
(TCP, UDP, etc.) on the Internet.
Primary (DNS) server
DNS servers usually have more than 2 systems and
the primary server is the main system.
Private (IP) address
IP address assigned when connecting primarily to
LAN. Private IP addresses can be assigned freely on
a network and do not require a formal application.
However, because private IP addresses cannot be
used to access the Internet, a router or other device it
is necessary to assign a global IP address.
Protocol
A set of rules that allows the exchange of data
amongst different types PCs with information. The
Internet uses the TCP/IP protocol as its base and
information is transferred following http and ftp proto-
cols depending on the application.
QVGA
Resolution with 320 x 240 (320 x 180) pixels.
QXGA
Resolution with 2048 x 1536 pixels.
RAID5
Even if a HDD becomes faulty, correct data can be
read from the remaining HDDs since 3 or more HDDs
are logically regarded as a single HDD and parity data
(error correction code data) is automatically attached.
Recorded images can be recovered by replacing the
failed HDD. 3 or more HDDs are required.
RAID6
Even if 2 HDDs become faulty, recorded images can
be recovered using the remaining HDDs since RAID6
has 2 parity data (error correction code data). 4 or
more HDDs are required.
Resolution (Image capture size)
Resolution refers to the degree of fineness and quality
of the camera pictures recorded by this product.
In this product, it indicates the number of pixels used
in the image displayed on the screen. A horizontal
resolution of 640 pixels and a vertical resolution of
480 pixels is expressed as 640x480.
Router
Placed in between different networks, a router sends
data to the proper destination via network. If data on
the network is addressed to an external network,
routers send the data to the outside of the network
after judging the optimum sending route.
Schedule recording
Function that automatically starts video and audio
recording on a preset time schedule.
SD memory card (Secure Digital memory card)
A small, lightweight and removable storage device
having a large capacity.
Secondary (DNS) server
DNS servers usually have more than 2 systems and
the secondary server is the sub system. If there is
trouble with the primary server, the secondary server
takes over.
SMTP (Simple Mail Transfer Protocol)
A protocol for sending e-mail on the Internet or an
Intranet. Used when transferring mail between serv-
ers or when clients send mail to the server.
SMTP authentication (Simple Mail Transfer
Protocol authentication)
SMTP mail transfer protocol appended with a user
authentication function. It authenticates passwords
and user accounts between SMTP servers and cli-
ents. Both SMTP servers and clients must support
SMTP authentication.
SMTP server
A server that supports SMTP, currently the most
widely used mail transfer protocol.
SNMP (Simple Network Management Protocol)
A protocol for monitoring and managing networked
communications devices, such as routers, PCs, cam-
eras and Network Disk Recorders via a network.
Subnet mask/Subnet prefix length
Numerical value to define whether to use several bits
for a network address to distinguish among subnet IP
addresses in a network. According to the values,
devices can determine which part of the address is
the network address and which part is the host
address.
