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CTI Janus Programmable Automation Controller IOG
4.2
Network Settings
Navigate to the C
ONFIGURATION
/N
ETWORK
S
ETTINGS
web page. This page allows you to set the following parameters.
4.2.1
IP Parameters
The N
ETWORK
S
ETTINGS
page allows you to configure the Primary Subnet and up to three Alternate Subnets.
Alternate Subnets allow you to communicate on additional IP subnets. It is not permitted to configure overlapping
subnets or assign more than one IP address to a subnet.
The Primary subnet IP parameters can be automatically obtained by DHCP (Dynamic Host Configuration Protocol)
or statically configured by entering the IP parameters. DHCP is not recommended for operational use, since it is
possible to receive different IP addresses from DHCP over time. Alternate Subnets must be statically configured.
See Alternate IP Subnets in APPENDIX C for more information.
4.2.2
DNS Configuration
It is possible to use DNS (Domain Name Service) to access a device (IP host) by name instead of IP address. This
will usually require coordination with your IT department to obtain the IP addresses of the Preferred and
Secondary (backup) DNS servers and the Domain Suffix.
If you want others to communicate with this controller by name, you will need to have a DNS entry in the DNS
server for it. Similarly, any device you want to communicate with by name must have an entry in the DNS server.
DNS settings for the Janus controller can be automatically read from the DNS server or manually entered.
4.2.3
Internal Ethernet Switch Configuration
By default, all Ethernet ports on the Janus controller are isolated from each other. Ethernet frames arriving at a
port are not forwarded to other external (front panel) Ethernet ports. Frames are forwarded only between an
external port and the controller microprocessor. This configuration protects against accidentally creating loops
which can occur when there are multiple connections between two network switches. When connected to
different networks, port isolation prevents broadcast and other traffic on each network from entering the other
network(s). See Ethernet Port Operation in APPENDIX C for more information.
Since there may be some applications that require forwarding between networks, you can choose other options
that allow forwarding in this web page.
