Excito B3, Руководство пользователя

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B3asrouterandfirewall
P
ort forward
A device connected on the Internet has at least one IP address. The IP address
is a unique number that is used to identify a device. Every IP address is divided
up into many ports.
When one device (for example a computer on the Internet) sends data to an-
other device (for example your computer at home), it sends the data from a
port on the external computers IP address to a port on your local computers
IP address. Computers on the Internet can not see the IP address on your local
computer at home, they only see your routers external IP address (that is B3’s
external IP address).
Some programs run on your local computer needs to have an “gate” exposed
to the Internet to function correctly: you need to use the function Port forward
in your firewall.
The Port forward tells your router in B3 which computer on the LAN to send
the data to. When you have set up the port forwarding rules, your rout-
er takes the data from the external IP-address:port number (for example
93.122.158.30:551, where 93.122.158.30 is the IP address and 551 is the port
number) and sends that data to an internal IP-address:port number (for exam-
ple 192.168.10.10:551).
In B3 Port forwarding rules are created per port or per a range of ports. A rule
set up for port 551 will only work for port 551. Rules set up for the port range
550-552 will open the three ports 550, 551, 552.