Appendix A Troubleshooting, Daily
Maintenance and Glossary
Glossary
DHCP.
Dynamic Host Configuration Protocol is one of the TCP/IP network protocols principally used
to assign temporary IP addresses to computers on a network.
DDNS.
Dynamic Domain Name Server is a service that maps Internet domain names to IP addresses.
This service is useful to anyone who wants to operate a server (Web server, mail server, FTP server,
etc.) connected to the Internet with a dynamic IP or to someone who wants to connect to an office
computer or server from a remote location with software.
GPS.
Global Positioning System is a satellite system, protected by the US military, safely orbiting
thousands of kilometers above the earth.
PPPoE.
Point to Point Protocol over Ethernet is a specification for connecting multiple computer
users on an Ethernet local area network to a remote site. Now the popular mode is ADSL and it
adopts PPPoE protocol.
WIFI.
Wi-Fi is the name of a popular wireless networking technology that uses radio waves to
provide wireless high-speed Internet and network connections. The standard is for wireless local area
networks (WLANs). It is like a common language that all the devices use to communicate to each
other. It is actually IEEE802.11, a family of standard The IEEE (Institute of Electrical and Electronics
Engineers Inc.)
Dual-stream.
The dual-stream technology adopts high-rate bit stream for local HD storage such as
QCIF/CIF/2CIF/DCIF/4CIF encode and one low-rate bit stream for network transmission such as
QCIF/CIF encode. It can balance the local storage and remote network transmission. The dual-stream
can meet the difference band width requirements of the local transmission and the remote
transmission. In this way, the local transmission using high-bit stream can achieve HD storage and
the network transmission adopting low bit stream suitable for the fluency requirements of the 3G
network such as WCDMA, EVDO, TD-SCDMA.
On-off value.
This is the non-consecutive signal sampling and output. It includes remote sampling
and remote output. It has two statuses: 1/0.
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