回複：十分十分感謝！

1) disable the router in the SPA3102, disable the DHCP server in the SPA3102, this will automatically disable the router
2) do not disable the DHCP client in your SPA3102, which is used for getting IP from your other router, connect the SPA3102 with a Ethernet cable to your other router
3) the spa3102 will automatically get IP from the other Router
4) every PC and equipments in your home should connect to your router not to the Modem, only the router is connected to the Modem.
5) in future you may need to set the SPA3102 to a static IP, and set port forwarding in your router, inorder to work with some dotcom, such as ipkall.com, they also provide you a free incomming call, but not outgoing. that is a future story.
6) Sipgate.com use dynamic IP, your DHCP client will get the IP from your router.