... WiFi ,802.11b/g), 1*SIM slot ,PPPoE/ADSL,NAT ,VOIP Ethernet Interface:1-2 *10/100Base-T;Calling Control Protocol ... : Hand free talking, Volume adjusting, Ringing tone selection, Call ID, Phone book, Missing incoming call, Incoming call, Outing call.failed outing ... transmission technology;The Managment of customer purview. HIP1860(3) IP Phone SIP PHONE connect with Voip gateway