FRITZ!Box Fon WLAN 7570 vDSL
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Glossary
It works by transmitting the current IP address to a special
DDNS server each time the IP address changes. Except for
the few seconds between the cancellation of the old IP ad-
dress and the notification of the new IP address, the com-
puter can always be reached at the selected domain name.
dynamic IP
address
A dynamic IP address is an IP address valid only for the du-
ration of one Internet or network session.
Every computer participating in the Internet must have a
uniquely assigned public IP address. Since only a limited
number of such IP addresses is available, they must be
used sparingly. That is why most of the Internet partici-
pants who dial in to the Internet receive a dynamic IP ad-
dress. They are called dynamic because every participant
receives a new public address that has not been assigned
yet each time he or she dials in to the Internet.
By contrast, dynamic addresses are usually used in local IP
networks because they are easy to handle, and because us-
ing them avoids incorrect IP address entries or unintention-
al double assignments. The DHCP service is responsible for
assigning unique dynamic IP addresses.
FAQ
abbreviation for Frequently Asked Questions
FAQs are collections with answers to frequently asked
questions on a certain subject area.
firewall
A firewall protects a computer or local network against at-
tacks from the Internet.
Most firewalls work with packet filters, which merely check
the IP addresses and port numbers of incoming and outgo-
ing data packets and filter the packets according to pre-
scribed rules.
Some firewalls also integrate additional concepts like IP
masquerading and NAT to decouple data traffic by distin-
guishing strictly between the internal and external network.
