User's Manual Network Camera HNC300, HNC320G

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D
DHCP Dynamic Host Configuration Protocol was developed by Microsoft and is a protocol for assigning
dynamic IP addresses to devices on a network. With dynamic addressing, a device can have a
different IP address every time it connects to the network. In some systems, the device's IP
address can even change while it is still connected. DHCP also supports a mix of static and
dynamic IP addresses. This simplifies the task for network administrators because the software
keeps track of IP addresses rather than requiring an administrator to manage the task. This means
a new computer can be added to a network without the hassle of manually assigning it a unique IP
address. DHCP allows the specification for the service provided by a router, gateway, or other
network device that automatically assigns an IP address to any device that requests one
DNS Domain Name System is an Internet service that translates domain names into IP addresses. Since
domain names are alphabetic, they're easier to remember. The Internet however, is really based
on IP addresses. Every time you use a domain name, the DNS will translate the name into the
corresponding IP address. For example, the domain name www.network_camera.com might
translate to 192.167.222.8.
E
Enterprise network An enterprise network consists of collections of networks connected to each other over a
geographically dispersed area. The enterprise network serves the needs of a widely distributed
company and operates the company’s mission-critical applications.
Ethernet The most popular LAN communication technology. There are a variety of types of Ethernet,
including 10 Mbps (traditional Ethernet), 100 Mbps (Fast Ethernet), and 1,000 Mbps (Gigabit
Ethernet). Most Ethernet networks use Category 5 cabling to carry information, in the form of
electrical signals, between devices. Ethernet is an implementation of CSMA/CD that operates in a
bus or star topology.
F
Fast Ethernet Fast Ethernet, also called 100BASE-T, operates at 10Mbps or 100Mbps over UTP, STP, or fiber-
optic media.
Firewall A firewall is considered the first line of defense in protecting private information. For better
security, data can be encrypted. A firewall is a system designed to prevent unauthorized access to
or from a private network. Firewalls are frequently used to prevent unauthorized Internet users
from accessing private networks connected to the Internet, especially Intranets. All messages
entering or leaving the intranet pass through the firewall, which examines each message and
blocks those that do not meet the specified security criteria.
G
Gateway A gateway links computers that use different data formats together.