Multi-Router Support for SIP Trunks
Voice over IP (VoIP)
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network are sent to an Internet router (the
default gateway
). The default
gateway forwards the data packets via the Internet connection (e.g. a DSL
line) and then returns the response packets to the communications system.
With some SIP providers, the relevant SIP connection must be established via
an associated Internet access. The general Internet access of the network
cannot be used for this purpose. In this case, an additional Internet connection
must be established in the configuration of the communications system and
assigned to the SIP trunk. However, for quality reasons, it can be useful to
connect an SIP trunk via a separate Internet access because, in this case, the
appropriate bandwidth is used exclusively for this access.
It is possible to use multiple different IP address ranges in a physical network.
With this set-up, for example, one group of devices could use only IP
addresses from 10.0.0.0 to 10.255.255.255, while another group of devices
only uses IP addresses from 192.168.99.0 to 192.168.99.255. This results in
two logically separated networks (
subnets
). Each group of devices can
therefore also use different routers (
gateways
) to access the Internet.
Furthermore, it is possible to configure multiple IP addresses for a network
device. A network device configured in this way can communicate directly with
devices from both groups. The Forum 5004/5008/5012 communications
system uses separate IP address ranges of this type to direct the data traffic
from one SIP trunk via a particular Internet router.
Note:
If you use an additional IP address range in a network, you do
not need to make any changes to the existing network compo-
nents (routers, switches, hubs) for this purpose.
Examples of Use
The examples of use provided in this chapter are based on the configuration
principles below. The “Multi-Router Support for SIP Trunks” feature in the
Forum 5004/5008/5012 communications system is implemented on the
basis of these principles.
●
In order to configure multiple gateways, multiple subnets must be set up.
These subnets can be located in one or more physical networks.
●
One gateway is configured per subnet.
●
One subnet is configured as a default subnet. The default subnet is
assigned to the default gateway of the communications system.
