New installation. Openreach engineeer has all the local phones working\nOK. One phone is intended for remote use, so:\n\n1) Site has internet connection with static IP (call it A.B.C.D)\n\n2) Phone is configured to look for public IP address of site.\n\n3) Internet router has TCP/UDP ports opened to the IP Office device, as\nfollows:\n\nPort 1719\nPort 1720\nPort 5000\nPort 5060\nPort range 49152 - 53246\n\n4) Openreach engineer called a colleague at another location, who\nconfigured a test phone with the correct IP, and was able to connect to\nthe IP Office at our site. So IP Office and router would seem to be\nconfigured correctly.\n\nHowever the phone does not connect to IP Office when installed at a\nremote site. Phone gets a local IP address by DHCP, shows some\nactivity, then hangs with "Discover A.B.C.D".\n\nThis appears to suggest it can't communicate with IP Office.\n\nDoes the router at the remote site need any port openings?\n\nIs there any other configuration needed at the remote site?\n\nOpenreach engineer seemed to be very limited on knowledge.