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Commissioning instructions OZW775 V2.01
CE1C5663en
HVAC Products
Appendix
22.06.2012
The public IP address is the worldwide valid (global) address of a network device on
the Internet. The ISP assigns these addresses. A network device with public IP address
is a device establishing a connection between local network LAN and the Internet. DSL
routers have a private IP address for the LAN and a public IP address for the WAN
(Internet).
PAT or NPAT (Network and Port Address Translation) translates all private network
addresses into one public (dynamic) IP address. In this process, port numbers are
exchanged in addition to addresses when there is a connection. As a result, an entire
private network only requires one single registered public IP address.
Ports are used to exchange data between different applications on a network. The port
number addresses the application within a network device. The combination of IP
address and port number serves as unique identification of the recipient or the sender
of the data package with the network.
Internet service applications work with set port numbers (HTTP
80, FTP
21).
for registered port numbers. Port
numbers 0 to 49151 are set and reserved, port numbers 49152 to 65535 are dynamic
and available.
With port forwarding, the router forwards data packages from the Internet, destined for
a particular port, to the port of the responsible network device. As a result, servers (web
server OZW775) integrated in a LAN, can be reached from the Internet (without a need
for a public IP address).
The private IP address (local IP address) is the address of a network device on a local
network (LAN). The provider assigns this address at will. DSL routers have a public IP
address for the WAN and a private IP address for the LAN. The following IP ranges are
recommended for private IP addresses:
10.0.0.0…10.255.255.255
Class A
172.16.0.0…172.31.255.255
Class B
192.168.0.0…192.168.255.255
Class C
The first IP address xxx.xxx.xxx.0 and the last IP address xxx.xxx.xxx.255 in a network
segment cannot be used, as xxx.xxx.xxx.0 is reserved for the network, xxx.xxx.xxx.255
for broadcasting.
A protocol describes the type of communication on a network. It contains rules on
opening, managing, and closing a connection, on data formats, time sequences, and
possible error correction. Different protocols are needed to allow two applications at
different levels to communicate with each other, e.g. TCP/IP protocols on the Internet.
Provider of telecommunications services. Network provider.
A router forwards data packages from a local network LAN to a higher network while
selecting the fastest route. A router allows for connecting different networks with
different network topologies. For example, the router connects a local network to the
Internet.
Public IP address
PAT (Port and Address
Translation)
Port
Port forwarding
Private IP address
Protocol
Provider
Router
