RTP (Real-time Transport Protocol) SetupIf the unit is connected to a network that uses a NAT router and a private IP address is assigned to eachterminal on the network, you must configure the RTP function for the unit and router so that the units canperform voice transmission between each other using a peer-to-peer connection.However, if your phone system supports the SBC (Session Border Controller) function, it is not necessary toconfigure these settings.For details about the SBC function, consult your phone system dealer.For details about Web user interface programming, see 4.4.5 Static NAPT Settings.Router SetupWhen configuring the port forwarding function, specify the router’s reception port number as the unit’s portnumber.Port forwarding should be configured for the ports specified in [Source Port] (® see SIP Setup in this section)and [External RTP Port] (® see RTP (Real-time Transport Protocol) Setup in this section).Set the same port number for the source port and destination port, and set the unit’s private IP address as thedestination address.Because the unit’s private IP address will have to be set in the router’s port forwarding configuration again ifit is changed, set a static IP address to the unit, or configure the router so that the same IP address is alwaysassigned to the unit if IP addresses are assigned by a DHCP server.For details about how to configure the router, refer to the documentation for the router.Because the port forwarding settings depend on the user’s network environment, they cannot be programmedusing configuration files.1.1.4.3 Global Address DetectionThe global IP address is a unique IP address that is assigned to a particular terminal. If the global IP addressassigned to the firewall or the router is changed, the unit will not be able to communicate.If the global IP addresses of these terminals are assigned by a DHCP server in the higher level network wherethey are connected, the IP address may differ each time the unit transmits data.The Global Address Detection feature detects the current global IP address and, if the IP address has changed,sets it automatically to the SIP server. There are 2 methods, using STUN (Simple Traversal of UDP throughNATs) or SIP messages, to perform this feature. For details about specifying this setting through the Web userinterface, see 4.4.4 Global Address Detection.Note• For details about server information, consult your network administrator.20 Administrator Guide Document Version 2012-07Section 1 Initial Setup
