Aastra OpenCom 510 User Manual page 14

Features
You can connect two OpenCom 510 systems (PBX cascading). Cascading is a
simple way of increasing the number of terminals that can be connected.
As your communication requirements grow, the OpenCom 510 can be networked
with other telecommunications systems. The OpenCom 510 can then operate as a
sub-system or as a DECT server. It is also possible to create a telecommunications
system with several networked PBXs.
Internet Access
For the purpose of providing Internet access, PCs can be connected to the
OpenCom 510 by means of the internal S
nected by means of the Ethernet port. If Internet access is already available from
an Internet service provider, the OpenCom 510 can be configured accordingly. The
OpenCom 510 can also be used for IP configuration if there is no IP-capable client
network. An integrated DHCP server and a DNS server will take over IP address
administration and name resolution for the client PCs.
The OpenCom 510 enables all connected PCs to access the Internet using a
common IP address; only the common address will be visible outside the LAN.
Network address translation (NAT) is used to change the IP addresses of the local
(client) PCs into the IP address of the OpenCom 510. This prevents direct access to
the LAN's client PCs and thus offers protection against attacks from the Internet.
The OpenCom 510 offers further protection of the LAN in the form of customisable
filter lists (firewall function).
DECT Data Communication
PCs that are not connected to the OpenCom 510 via the internal S
Ethernet interface can access the Internet if used in combination with the
OpenPhone 27 DECT terminals. PCs in these configurations can also make full use
of the Internet and e-mail features of the OpenCom 510.
Data will then be transmitted via the internal data interface of the OpenPhone 27.
The OpenPhone 27 must be connected to the serial port of the PC. The Internet
can be accessed directly via the remote data transfer (i.e. dial-up) network. The
OpenPhone 27 will establish a data connection with the OpenCom 510 via the
DECT air interface. The Internet connection itself will be established either directly
through an ISDN B-channel or indirectly through the internal RAS interface of the
OpenCom 510. Indirect RAS access is preferable as it uses the routing function of
12
Note: Also observe the notes in Useful Information on Inter-
net Access starting on page 102.
ports, and an entire LAN can be con-
0
ports or the
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