FRITZ!Box 6810 LTE
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Glossary
dynamic IP address
A dynamic IP address is an IP address valid only for the dura-
tion 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 participants who
dial in to the Internet receive a dynamic IP address. They are
called dynamic because every participant receives a new
public address that has not been assigned yet each time she
or he connects 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 unintentional
double assignments.
fixed IP address
Fixed IP addresses are IP addresses (
) which are
permanently assigned to a computer or another device like a
network printer.
Assigning fixed IP addresses makes sense in cases where a
computer is always supposed to be accessible at a certain ad-
dress (for instance, a web server or an e-mail server).
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 outgoing
data packets and filter the packets according to prescribed
rules.
Within IPv4 networks, some firewalls also integrate addition-
al concepts like IP masquerading and NAT to decouple data
traffic by distinguishing strictly between the internal and ex-
ternal network.
Summary of Contents for 6810 LTE
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