Glossary
SINAUT MD741-1
C79000-G8976-C236-05
143
DynDNS provider
Also
Dynamic DNS provider
. Every computer that is connected to the
Internet has an IP address (IP = Internet Protocol). An IP address
consists of up to 4 three-digit numbers, with dots separating each of
the numbers. If the computer is online via the telephone line via
modem, ISDN or ADSL, then the Internet service provider dynamically
assigns it an IP address, i.e. the address changes from session to
session. Even if the computer is online for more than 24 hours without
interruption (e.g. in the case of a flat rate), the IP address is changed
periodically.
For a local computer to be accessible via the Internet, its address must
be known to the external remote station. This is necessary for it to
establish a connection to the local computer. This is not possible,
however, if the address of the local computer constantly changes. It is
possible, however, if the user of the local computer has an account
with a DynamicDNS provider (DNS = Domain Name Server).
Then he can specify there a hostname under which the computer can
be accessed in the future, e.g.: www.xyz.abc.de. Moreover, the
DynamicDNS provider makes available a small program that has to be
installed and executed on the computer concerned. In each Internet
session of the local computer this tool reports to the DynamicDNS
provider which IP address the computer has at the moment. Its domain
name server registers the current hostname - IP address assignment
and reports this to other domain name servers in the Internet.
If now an external computer wants to establish a connection with a
local computer which is registered with the DynamicDNS provider, the
external computer uses the hostname of the local computer as the
address. In this way a connection is established with the responsible
DNS (Domain Name Server) in order to look up there the IP address
which is currently assigned to this hostname. The IP address is
transmitted back to the external computer, and then used by it as the
destination address. This now leads precisely to the desired local
computer.
As a rule, all Internet addresses are based on this method: First a
connection is established to a DNS in order to determine the IP
addresses assigned to this hostname. Once that has been done, the
IP address that was "looked up" is used to establish the connection to
the desired remote station, which can be any Web site.
EDGE
EDGE (= Enhanced Data Rates for GSM Evolution) refers to a method
in which the available data rates in GSM mobile phone networks are
increased by introducing an additional modulation process. With
EDGE, GPRS is expanded to become EGPRS (Enhanced GPRS), and
HSCSD is expanded to become ECSD.
EGPRS
EGPRS stands for "Enhanced General Packet Radio Service", which
describes a packet-oriented data service based on GPRS, which is
accelerated by means of EDGE technology.
