Siemens Gigaset C470 IP Manual page 175

Glossary
DMZ (Demilitarised Zone)
DMZ describes a part of a network that is outside the firewall.
A DMZ is set up, as it were, between a network you want to protect (e.g. a LAN) and a
non-secure network (e.g. the Internet). A DMZ permits unrestricted access from the
Internet to only one or a few network components, while the other network compo-
nents remain secure behind the firewall.
DNS
Domain Name System
Hierarchical system that permits the assignment of IP addresses to Domain names that
are easier to note. This assignment has to be managed by a local DNS server in each
(W)LAN. The local DNS server determines the IP address, if necessary by enquiring about
superordinate DNS servers and other local DNS servers on the Internet.
You can specify the IP address of the primary/secondary DNS server.
See also: DynDNS.
Domain name
Name of one (of several) Web server on the Internet (e.g. Siemens Home) The domain
name is assigned to the relevant IP address by DNS.
DSCP
Differentiated Service Code Point
See Quality of Service (QoS).
DSL
Digital Subscriber Line
Data transfer technology that allows Internet access with, for e.g., 1.5 Mbps over a con-
ventional telephone line. Preconditions: DSL modem and the appropriate service
offered by the Internet provider.
DSLAM
Digital Subscriber Line Access Multiplexer
The DSLAM is a switch cabinet in an exchange at which all subscriber connectors con-
verge.
DTMF
Dual Tone Multi-Frequency
Another description for dual tone multi-frequency dialling.
Dynamic IP address
A dynamic IP address is assigned to a network component automatically via DHCP. The
dynamic IP address for a network component can change every time it registers or at
certain time intervals.
See also: Static IP address
DynDNS
Dynamic DNS
Domain names and IP addresses are realised via DNS. For Dynamic IP addresses this
service is now enhanced with "Dynamic DNS" (DynDNS). This permits the use of a net-
work component with a dynamic IP address as a Server on the Internet. DynDNS
ensures that a service can always be addressed on the Internet under the same Domain
name irrespective of the current IP address.
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