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Glossary
IP address
A fixed IP address is allocated to each TCS:BUS camera and TCS:BUS front-door station. Thus, a
specific switch-over via VSW04 or FVU1220 is feasible. Each AS address in the range from 0 to 63
can be assigned only once.
resolution
The resolution specifies with how many pixel an image is displayed. The more pixel, the better de-
tails can be seen in the enlargement. The resolution is specified in pixel columns by pixel lines or as
total pixel amount. A VGA image consists of 640 columns and 480 lines (640 x 480). That is a total of
307200 pixel. A QVGA image consists of 320 columns and 240 lines (320 x 240). That is a total of
76,800 pixel.
image refresh rate
The image refresh rate specifies how many images per second (I/s) are created and sent by the
camera. As of 16 I/s the image sequence is perceived as fluent video sequence by the human eye.
CMOS sensor
Abbreviation for Complementary Metal Oxid Semiconductor Sensor. Sensor for energy-saving digit-
isation of image information. CMOS sensors are used as image sensors in digital cameras.
DHCP
Abbreviation for Dynamic Host Configuration Protocol. DHCP is a service within IP networks. By
using DHCP specific configurations such as IP address, subnet mask, DNS server and standard
gateway can be allocated to devices automatically via a server (contrary to IP addresses that are
manually assigned to single network devices).
DNS
The Domain Name System (DNS) is one of the most important services within the network. It trans-
lates e.g. the name of a website into an IP address. The main task of the DNS is to respond requests
for name resolutions.
Domain
Logical grouping of network devices.
Ethernet
Ethernet is the most common LAN technology. Usually twisted pairs of conductors with special
characteristics (e.g. CAT6) are used in Ethernet LAN'S. The most common Ethernet standards are
10BASE-T and 100BASE-T10. These standards enable transmission speeds up to 10 Mbit/s resp.
100 Mbit/s.
Host
Computer that provides services within a computer network.
IP address
The IP address designates the address of a computer or device within an IP network. With an IP
address a computer that is connected to an IP network can be identified unambiguously. By setting
the IP address a communication to another computer/device can be established. Each IP address
must be assigned only once in the respective network to avoid conflicts. IP addresses can be as-
signed fix that they always remain the same. Alternatively they can be assigned dynamically (or
automatically) via DHCP. There are IP addresses with 4 and 6 bytes. The 4 bytes version is the most
commonly used. In standard an IPv4 address is specified as decimal number from 0 to 255 separat-
ed by dots (e.g. 192.168.178.1). Due to the fact that there are more IP devices than unique IPv4 ad-
dresses, IP addresses are divided in private and public ones. Private IP addresses are not forwarded
via router (they remain in the LAN). They start with the prefixes 10.*.*.*, 172.16-32.*.* and
192.168.*.*. The public IP addresses (globally unique) are assigned by providers.
IP camera
An IP camera is special kind of camera. The special aspect of this camera is that images are trans-
mitted via IP networks. Additionally to the camera component, network cameras contain a comput-
er. The integrated computer compresses the image data and sends the data via the net. The com-
puter essentially consists of a CPU, a flash memory and a DRAM memory. Due to the software of
the network camera, the device can act as web server, FTP server, FTP client and E-Mail client in
the net.
IP network
Packet-oriented data network based on the Internet Protocol (IP).
LAN (Local Area Net-
work)
A LAN consists of several computer and the associated devices, which are using the same commu-
nication resources within a limited geographic area.
