8.6.15 Dynamic NAPT (IP masquerade)DescriptionThis feature dynamically changes the address and port of packets accessing the WAN from the LAN. Thismakes it possible for multiple devices to connect to the outside.You can enable and disable this feature for each built-in router.NoteThe PBX must remember the mapping of IP addresses and ports for packets leaving the LAN. Therefore,it is not possible to directly access a LAN-side device from the WAN side.This acts as a security measure, preventing unauthorised access from outside the LAN.Conditions• This PBX supports only dynamic NAPT (IP masquerade). It does not support dynamic NAT.• Protocols that can use this feature are: TCP(6), UDP(17), and ICMP (1). For ICMP, the ICMP query ID ischanged instead of the port number.• If the router is being used as an edge router, the dynamic NAPT feature will be enabled. If the router isbeing used as a local router, the dynamic NAPT feature will be disabled.• Conforming RFCsRFC 1631: The IP Network Address Translator (NAT)RFC 2391: Load Sharing using IP Network Address Translation (LSNAT)PC Programming Manual References27.3.1 Router Configuration—Setup—[1-3-1] LAN—IPv48.6.16 Static NAPT (Port Forwarding)DescriptionBy mapping a specific port on the WAN side (for example 80 for HTTP) to a device on the LAN side (IP addressand port), packets that arrive on the WAN side at the specified port can be forwarded to the device.The static NAPT (port forwarding) feature can be enabled and disabled for each built-in router.Conditions• This PBX supports only static NAPT (port mapping/static IP masquerade). It does not support static NAT.• A maximum of 64 entries can be registered.• Protocols that can use this feature are: TCP(6), UDP(17), and ICMP (1).• You can set a range of ports using the condition that the WAN-side port number and LAN-side port numberbe the same number.• A maximum of 4096 sessions can be managed. This session number includes dynamic NAPT settings.• Conforming RFCs:RFC 1631: The IP Network Address Translator (NAT)RFC 2391: Load Sharing using IP Network Address Translation (LSNAT)PC Programming Manual References27.3.1 Router Configuration—Setup—[1-3-1] LAN—IPv4358 Installation Manual8.6.16 Static NAPT (Port Forwarding)
