The Gateway is an interface on the IP network that allows signals from, or to, its ports to be converted onto the LAN network. In the case of conversion from analogue to VOIP, a gateway with the code 1375/864 is used. In the case of conversion from ISDN to VOIP, on the other hand, a gateway with the code 1375/872 is used. If the VOIP signal needs to be converted to make it compatible with analogue telephones or devices, the 1375/854 (4-port) or 1375/859 (16-port) gateway is used.