User manual

119
Glossary
Gigaset DX600A isdn / Swisscom EN / A31008-N3101-F151-1-7619 / Glossary.fm / 20.05.2010
Version 4, 16.09.2005
Consultation call
You are on a call. With a consultation call, you
interrupt the conversation briefly to estab-
lish a second connection to another partici-
pant. If you terminate the connection to this
participant immediately, then this was a
consultation call. If you switch between the
first and second participant, it is called Call
swap.
D
DHCP
Dynamic Host Configuration Protocol
Internet protocol that handles the automatic
assignment of IP addresses to Network sub-
scriber. The protocol is made available in the
network by a server. A DHCP server can, for
example, be a router.
The phone contains a DHCP client. A router
that contains a DHCP server can assign the IP
addresses for the phone automatically from
a defined address block. The dynamic
assignment means that several Network
subscribers can share one IP address,
although they can only use it alternately and
not simultaneously.
With some routers you can specify that the IP
address for the phone is never changed.
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 net-
work 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 com-
ponents, while the other network compo-
nents remain secure behind the firewall.
DNS
Domain Name System
Hierarchical system that permits the assign-
ment of IP addresses to Domain names that
are easier to memorise. 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 pri-
mary/secondary DNS server.
See also: DynDNS.
Domain name
Name of one (or several) Web server(s) on
the Internet. The domain name is assigned
to the relevant IP address by DNS.
DSL
Digital Subscriber Line
Data transfer technology that allows Inter-
net access with e.g., 1.5 Mbps over a conven-
tional telephone line. Prerequisites: 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
converge.
DTMF
Dual Tone Multi-Frequency
Another description for dual tone multi-fre-
quency dialling (DTMF).
Dynamic IP address
A dynamic IP address is assigned to a net-
work component automatically via DHCP.
The dynamic IP address for a network com-
ponent can change every time it registers or
at certain time intervals.
See also: Fixed IP address
DynDNS
Dynamic DNS
Domain names and IP addresses are
assigned via DNS. For Dynamic IP addresses
this service is enhanced with "Dynamic
DNS". This permits the use of a network com-
ponent 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 names
regardless of the current IP address.