Siemens Gigaset S675IP User Manual page 142

The choice of codec is a compromise
between voice quality, transmission
speed and the necessary bandwidth. A
high level of compression, for example,
means that the bandwidth required for
each voice connection is low. However,
it also means that the time needed to
compress/decompress the data is
greater, which increases execution
time for data in the network and thus
impairs voice quality. The time required
increases the delay between the sender
speaking and the recipient hearing
what has been said.
Consultation call
You are on a call. With a consultation
call, you interrupt the conversation
briefly to establish a connection to
another participant. If you terminate
the connection to this participant
immediately, then this was then this
was a consultation call. If you switch to
and fro between the first and second
participants, it is called Toggling.
D
DHCP
Dynamic Host Configuration Protocol
Internet protocol that handles the auto-
matic assignment of IP addresses to
Network subscribers. The protocol is
made available in the network by a
server. A DHCP server can be a router
for example.
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 use
it alternately and not simultaneously.
With some routers you can specify that
the IP address for the phone is never
changed.
Displayed name
VoIP provider feature. You can specify
any name that is to be shown to the
other party during a call instead of your
phone number.
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 unre-
stricted access from the Internet to only
one or a few network components,
while the other network components
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(s)
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 conventional telephone line.
Preconditions: DSL modem and the
appropriate service offered by the
Internet provider.
Glossary
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