Abstract: A system and method for IP telephony are disclosed, including an IP telephone (IPT) and a Service Gateway (SG). The SG receives an identifier, e.g., a vendor class identifier, included in a DHCP discover message from the IP telephone and determines the identifier's validity. If so, the SG issues a DHCP offer comprising DHCP lease information to the IP telephone, including a range of port numbers assigned to the IP telephone based on the identifier, where the range of port numbers comprises ports which are not reserved for use by other IP protocols. The DHCP lease information includes information indicating operational software for the IP telephone which the IP telephone executes to enable IP communications. The SG mediates IP communications between the IP telephone and an IP device, where the IP telephone uses at least a subset of the range of port numbers to send or receive IP communications.

Abstract: A system and method for IP telephony are disclosed. The system includes an IP telephone (IPT) and a Service Gateway (SG). The SG receives an identifier, e.g., a vendor class identifier, included in a DHCP discover message from the IP telephone and determines if the identifier is valid. If so, the SG issues a DHCP offer comprising DHCP lease information to the IP telephone, including a range of port numbers assigned to the IP telephone based on the identifier, where the range of port numbers comprises ports which are not reserved for use by other IP protocols. The DHCP lease information includes information indicating operational software for the IP telephone which the IP telephone executes to enable IP communications. The SG mediates IP communications between the IP telephone and an IP device, where the IP telephone uses at least a subset of the range of port numbers to send or receive IP communications.

Abstract: System and method for IP telephony. The system includes an IP telephone (IPT) and a Service Gateway (SG). The SG receives an identifier, e.g., a vendor class identifier, included in a DHCP discover message from the IP telephone and determines if the identifier is valid. If so, the SG issues a DHCP offer comprising DHCP lease information to the IP telephone, including a range of port numbers assigned to the IP telephone based on the identifier, where the range of port numbers comprises ports which are not reserved for use by other IP protocols. The DHCP lease information includes information indicating operational software for the IP telephone which the IP telephone executes to enable IP communications. The SG mediates IP communications between the IP telephone and an IP device, where the IP telephone uses at least a subset of the range of port numbers to send or receive IP communications.

Abstract: An IP-telephony system including one or more nodes coupled to a session controller. Each node includes a service gateway coupled to one or more terminals. A first terminal conveys a start page request initiating a page activity between itself and one or more terminating terminals. The session controller receives the start page request and in response, conveys first control signals to one or more service gateways, each first control signal containing information identifying which of the terminals associated with a service gateway is a terminating terminal. In response to the first control signal, each service gateway conveys second control signals to its associated terminating terminals. The first terminal conveys a media packet to the first service gateway during a page activity. The first service gateway forwards the media packet to one or more designated terminating terminals.

Abstract: System and method for IP telephony including internal and external call sessions. The system includes at least one IP telephone (IPT), a Service Gateway (SG), and a Media Gateway Controller (MGC). The SG receives a Call Setup request, including a source IP address and a destination telephone number. A first Media Gateway is selected based on the source IP address. A second Media Gateway is selected based on the destination telephone number. A public IP address of the first Media Gateway is compared to a public IP address of the second Media Gateway, and if the same, respective private IP addresses of the first and second Media Gateway are selected for Call Setup. If different, the respective public IP addresses of the first and second Media Gateway are selected for Call Setup. Thus, the system and method distinguish between external and internal call sessions and route the IP traffic accordingly.

Abstract: System and method for routing packets for IP telephony. The system includes an IP telephone (IPT) and a Service Gateway (SG) coupled via a network. The SG receives a data packet from the IPT, including a private source IP address (SIPA), source port number (SPN), and destination information for an IP device, performs network address persistent port translation (NAPPT) on the data packet, and sends it to the IP device. NAPPT changes the private SIA to a public SIA, leaving the SPN unchanged. The SG receives a data packet from the IP device, including a public destination IP address (DIPA, i.e., said public SIPA), a destination port number (DPN, i.e., said SPN), and source information, NAPPTs the data packet, using the public DIPA and the DPN to identify the IPT, changing the public DIPA to the private SIPA, leaving the DPN unchanged, and sends the data packet to the IPT.

Abstract: System and method for IP telephony. The system includes at least one IP telephone (IPT), a Service Gateway (SG), and a Media Gateway Controller (MGC). After the IPT is activated, the SG performs client DHCP lease negotiation with the IPT, using an identifier of the IPT to assign a range of ports to the IPT, and providing DHCP lease information, which is stored on the SG and the IPT. Operational software is downloaded from a TFTP server and executed by the IPT for initialization. The MGC registers the IPT, which then performs IP communications using one or more ports in the range of assigned ports, where the SG receives packets, performs NAPPT on source/destination IP addresses in the packet header for outgoing/incoming calls, while leaving port information unchanged, and sends the packets on to their destination, where the IPT is uniquely identified using a public IP address and port number.