Glossary

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 making 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 an enquiry 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 which handles the automatic assignment of IP addresses to Network subscribers. The protocol is made available in the network by a server. A DHCP server can e.g. 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. This 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 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 unrestricted access from the Internet to only one or a few network compo- nents, while the other network components remain secure behind the fire- wall.

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 of superordinate DNS servers and other local DNS servers in 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 which allows Internet access at e.g. 1.5 Mbps over conventional phone lines. Require- ments: DSL modem and the appropriate service offered by the Internet pro- vider.

DSLAM

Digital Subscriber Line Access Multiplexer

The DSLAM is a switch cabinet in an exchange at which all subscriber connectors converge.

112