Technical Specs

1.4 Glossary
DHCP The Dynamic Host Configuration Protocol (DHCP) is used to automatically assign an IP address to a
network device. Some DHCP servers only accept known devices. In this case, an administrator needs to
configure the DHCP server with the fixed MAC address of a device.
DNS
mDNS The Domain Name Server (DNS) manages the host names and IP addresses of all network devices. It is
responsible for resolving the host name into the IP address for communication with a device. A DNS can
be configured to get this information automatically when a device appears on a network or manually by an
administrator. In contrast, multicast DNS (mDNS) works without a central server by querying all devices
on a local network each time a host name needs to be resolved. mDNS is available by default on Linux and
Mac operating systems and is used when ‘.local’ is appended to a host name.
GenICam GenICam is a generic standard interface for cameras. It serves as a unified interface around other
standards such as GigE Vision, Camera Link, USB, etc. See http://genicam.org for more information.
GigE Gigabit Ethernet (GigE) is a networking technology for transmitting data at one gigabit per second.
GigE Vision GigE Vision® is a standard for configuring cameras and transmitting images over a GigE network
link. See http://gigevision.com for more information.
IMU An Inertial Measurement Unit (IMU) consists of three accelerometers and three gyroscopes that measure
the linear accelerations and the turn rates in all three dimensions.
INS An Inertial Navigation System (INS) is a 3D measurement system which uses inertial measurements (accel-
erations and turn rates) to compute position and orientation information. We refer to our combination of
stereo vision and inertial navigation as stereo INS.
IP
IP address The Internet Protocol (IP) is a standard for sending data between devices in a computer network.
Every device requires an IP address, which must be unique in the network. The IP address can be configured
by DHCP, Link Local, or manually.
Link Local Link Local is a technology where network devices associate themselves with an IP address and check
if it is unique in the local network. Link Local can be used if DHCP is unavailable and manual IP configu-
ration is not or cannot be done. Link Local is especially useful for connecting a network device directly to a
host computer. By default, Windows 10 reverts automatically to Link Local if DHCP is unavailable. Under
Linux, Link Local must be enabled manually in the network manager.
MAC address The Media Access Control (MAC) address is a unique, persistent address for networking devices.
It is also known as the hardware address of a device. In contrast to the IP address, the MAC address is
(normally) permanently given to a device and does not change.
NTP The Network Time Protocol (NTP) is a TCP/IP protocol for synchronizing time over a network. Basically
a client requests the current time from a server, and uses it to set its own clock.
PTP The Precision Time Protocol (PTP, also known as IEEE1588) is a protocol which enables more precise and
robust clock synchronization than with NTP.
SDK A Software Development Kit (SDK) is a collection of software development tools or a collection of software
modules.
SGM SGM stands for Semi-Global Matching and is a state-of-the-art stereo matching algorithm which offers
brief run times and a great accuracy, especially at object borders, fine structures, and in weakly textured
areas.
SLAM SLAM stands for Simultaneous Localization and Mapping and describes the process of creating a map of
an unknown environment and simultaneously updating the sensor pose within the map.
UDP The User Datagram Protocol (UDP) is the minimal message-oriented transport layer of the Internet Protocol
(IP) family. It uses a simple connectionless transmission model with a minimum of protocol mechanism
such as integrity verification (via checksum). The rc_visard uses UDP for publishing its estimated dynami-
cal states (Section 6.3.2) via the rc_dynamics interface (Section 8.3). To receive this data, applications may
1.4. Glossary 6