Abstract: In one embodiment, an automatically maintained, distributed source tree (DST) network has a plurality of fully connected internal nodes. One or more internal nodes may be connected to one or more external nodes. A first internal node synchronizes its link-state database with another internal node by sending and receiving respective Reduced Sequence Number Packet-Data-Units (PDUs) (RSNPs). An RSNP includes summary information for link-state packets (LSPs) (1) originated by the first internal node, (2) received by the first internal node from the other internal node, and (3) received from and/or originated by external nodes. If an internal link fails, then the corresponding end-nodes may recover and maintain automatic DST operation by entering either relay-mode or switch-mode operation. In relay-mode operation, an end-node tunnels packets to the other end-node via an intermediary node. In switch-mode operation, an intermediary node is selected to forward packets from one end-node to the other end-node.

Abstract: A method and apparatus are provided for a gateway which interconnects public safety wireless networks and commercial wireless networks that support push-to-talk group calls. The gateway translates Real Time Protocol (RTP), Session Invitation Protocol (SIP), and Talk Burst Control Protocol (TBCP)/Real Time Control Protocol (RTCP) messages received from the commercial wireless network and RTP and SIP messages received from the public safety wireless network into a format of the receiving network. The gateway has a call control component operable to set up and tear down RTP connections between the networks, a push-to-talk control component operable to arbitrate calls between wireless communications handsets of both networks, and a transmission control component operable to transfer media packets between the networks. The gateway reduces the number of call set ups required when a caller wants to speak because connections may remain active until the talk group participants leave the push-to-talk group call.

Abstract: A method and apparatus are provided for a set of procedures that a push-to-talk (PTT) server can use to control multiple simultaneous media streams within a talk group. The present invention provides floor control messages and protocols for identifying, transmitting, and distributing the simultaneous media streams. The invention may be used with any real-time protocol (RTP) payload format as long as the encoding allows a receiver of the packets means to distinguish between the transmitting clients. Although the present invention provides server-based control of multiple transmissions, end-point-based transmission control procedures are supported.

Abstract: In one embodiment, a method for processing, at an enhanced Session Initiation Protocol (SIP) proxy (e-proxy), (1) a SIP INVITE message to a first user at an IPv4/IPv6 dual-stack (DS) host, connected to an IPv6 network, from a second user at an IPv4 host, connected to an IPv4 network. The e-proxy receives the SIP INVITE message from the IPv4 network. When the e-proxy determines that Dual Stack Transition Mechanism (DSTM) service is required, the e-proxy obtains a temporary IPv4 address for the DS host, finds a suitable tunnel end-point (TEP), and sends a corresponding, but modified, INVITE message to the DS host. The modified INVITE message body includes invocation of DSTM service, the temporary IPv4 address, the TEP's IPv6 address, and the IPv4 host's IPv4 address. The e-proxy sends a BIND message to the TEP to bind the DS host's IPv6 address to the temporary IPv4 address for proper tunneling.

Abstract: A method and apparatus for configuring connectivity at a hub having a plurality of subscriber lines from a plurality of subscriber premises and a plurality of feeder lines from a central office. The hub provides connectivity between the plurality of subscriber premises and the central office. The method and apparatus include categorizing the plurality of subscriber lines into a plurality of groups based on penetration rates and churn rates of the plurality subscriber lines. Each group of subscriber lines are connected to feeder lines based on the penetration and churn rates for POTS and/or DSL services. Subscriber line groups with high penetration rates and high/low churn rates are coupled directly to feeder lines. Subscriber line groups with low penetration rates and high/low churn rates are terminated at the hub. Subscriber lines with an intermediate penetration rate are candidates for being connected to the feeder lines via an automatic switch.

Abstract: Apparatus for providing connectivity at a hub having a plurality of subscriber lines and a plurality of feeder lines. The apparatus includes a first switch module for coupling to N of the plurality of subscriber lines, where N is an integer. The first switch module is also for coupling to a digital subscriber line access modem (DSLAM) at the hub. A second switch module is coupled to the first switch module and the DSLAM. The second switch module is also adapted for coupling to M of the plurality of feeder lines at the hub, where M is an integer.

Abstract: In one embodiment, a method for setting up a flow-through mesh group (FTMG) for transmitting link-state packets (LSPs) in a network having a plurality of nodes interconnected by links. The FTMG is a combination of multiple spanning trees for the network through which LSPs are forwarded. FTMG set-up messages are received at ports of each node of the network from peer ports of linked nodes. FTMG set-up messages identify root nodes of the multiple spanning trees and the transmission modes of the peer ports. The FTMG set-up messages are used to determine (1) a root node for each spanning tree, (2) a root port on each node for each spanning tree, and (3) directionality of ports of the nodes. FTMG set-up messages are then used to determine the transmission mode of ports of the nodes and, subsequently, to update the spanning trees and transmission modes, as needed.

Abstract: In one embodiment, an automatically maintained, distributed source tree (DST) network has a plurality of fully connected internal nodes. One or more internal nodes may be connected to one or more external nodes. A first internal node synchronizes its link-state database with another internal node by sending and receiving respective Reduced Sequence Number Packet-Data-Units (PDUs) (RSNPs). An RSNP includes summary information for link-state packets (LSPs) (1) originated by the first internal node, (2) received by the first internal node from the other internal node, and (3) received from and/or originated by external nodes. If an internal link fails, then the corresponding end-nodes may recover and maintain automatic DST operation by entering either relay-mode or switch-mode operation. In relay-mode operation, an end-node tunnels packets to the other end-node via an intermediary node. In switch-mode operation, an intermediary node is selected to forward packets from one end-node to the other end-node.

Abstract: An exemplary embodiment of a method is implemented in a wireless network and is advantageous in that an undesired interim media channel link which would have been used in prior art systems is identified during call setup and avoided. In response to a call request in the wireless network for a call with a first user's wireless subscriber unit, a determination is made if one of a calling home node and a called home node of the first user's wireless subscriber unit should not be used as a node in the media channel such as due to the one node's remote location relative to the rest of the nodes in the media channel. A resulting media channel is established so that the one of the calling home node and the called home node is not part of a path of the media channel thereby minimizing the total distance and delay of the media path.

Abstract: Reduction of administrative overhead in maintaining network information, rapid convergence on an optimal routing path through the data network, and utilization of only required network resources are realized by a novel method for establishing a call path between network users. The method is based upon deployment of a network information server that stores network topology information and that is addressable by each end user. In this method, the network information server receives a request to establish a call path. The request identifies at least the calling party. In response to the request, the network information server determines a network traversal between the calling party and a root network wherein the network traversal includes call path information about the sub-networks between the calling party and the root network. The request for establishing a call path can also identify the called party.

Abstract: A method and apparatus for configuring connectivity at a hub having a plurality of subscriber lines from a plurality of subscriber premises and a plurality of feeder lines from a central office. The hub provides connectivity between the plurality of subscriber premises and the central office. The method and apparatus include categorizing the plurality of subscriber lines into a plurality of groups based on penetration rates and chum rates of the plurality subscriber lines. Each group of subscriber lines are connected to feeder lines based on the penetration and chum rates for POTS and/or DSL services. Subscriber line groups with high penetration rates and high/low chum rates are coupled directly to feeder lines. Subscriber line groups with low penetration rates and high/low chum rates are terminated at the hub. Subscriber lines with an intermediate penetration rate are candidates for being connected to the feeder lines via an automatic switch.

Abstract: In one embodiment, a method for processing, at an enhanced Session Initiation Protocol (SIP) proxy (e-proxy), (1) a SIP INVITE message to a first user at an IPv4/IPv6 dual-stack (DS) host, connected to an IPv6 network, from a second user at an IPv4 host, connected to an IPv4 network. The e-proxy receives the SIP INVITE message from the IPv4 network. When the e-proxy determines that Dual Stack Transition Mechanism (DSTM) service is required, the e-proxy obtains a temporary IPv4 address for the DS host, finds a suitable tunnel end-point (TEP), and sends a corresponding, but modified, INVITE message to the DS host. The modified INVITE message body includes invocation of DSTM service, the temporary IPv4 address, the TEP's IPv6 address, and the IPv4 host's IPv4 address. The e-proxy sends a BIND message to the TEP to bind the DS host's IPv6 address to the temporary IPv4 address for proper tunneling.

Abstract: Establishing voice calls in an IP based VPN includes determining the relative location of a terminating point with respect to an originating point of a new communication containing the voice data, determining one or more IP addresses to egress the communication from the originating point to the terminating point, creating a VPN identifier in the new communication, passing the new communication to the terminating point and removing the VPN identifier from the new communication. The VPN identifier can be an extra field added to an encapsulation coding scheme of the voice data.

Abstract: A method and apparatus are provided for a set of procedures that a push-to-talk (PTT) server can use to control multiple simultaneous media streams within a talk group. The present invention provides floor control messages and protocols for identifying, transmitting, and distributing the simultaneous media streams. The invention may be used with any real-time protocol (RTP) payload format as long as the encoding allows a receiver of the packets means to distinguish between the transmitting clients. Although the present invention provides server-based control of multiple transmissions, end-point-based transmission control procedures are supported.

Abstract: An exemplary gateway apparatus provides push-to-talk (PTT) communications between users in one network with users in another network where the networks utilize different communication protocols. It includes two protocol modules that interface with the two networks, respectively. The protocol modules are capable of receiving and transmitting messages compatible with the communication protocols used by the associated networks. An interoperability module, connected between the two modules, converts PTT control messages received from one of the networks into PTT control messages compatible with and transmitted to the other network. The PTT control messages received from the one network have a protocol that differs from the protocol of the PTT control messages transmitted to the other network.

Abstract: A method and apparatus are provided for a gateway which interconnects public safety wireless networks and commercial wireless networks that support push-to-talk group calls. The gateway translates Real Time Protocol (RTP), Session Invitation Protocol (SIP), and Talk Burst Control Protocol (TBCP)/Real Time Control Protocol (RTCP) messages received from the commercial wireless network and RTP and SIP messages received from the public safety wireless network into a format of the receiving network. The gateway has a call control component operable to set up and tear down RTP connections between the networks, a push-to-talk control component operable to arbitrate calls between wireless communications handsets of both networks, and a transmission control component operable to transfer media packets between the networks. The gateway reduces the number of call set ups required when a caller wants to speak because connections may remain active until the talk group participants leave the push-to-talk group call.

Abstract: In a floor control system for a network, a floor control server controls a floor-based application for communications between multiple participant terminals. The server carries out a floor determination process that includes an adaptive waiting function. Upon receiving an initial floor request message, the server waits for additional requests before determining the floor winner. The wait time is a function of the floor request load. When the system is lightly loaded, the wait time is generally small. For heavier request loads, the wait time is generally longer, to ensure that a reasonable number of requests are received before awarding the floor. The wait time may be limited by a maximum wait time, which is a function of the floor request load. If a designated number of floor requests is received before the maximum wait time expires, a temporary floor winner is granted the floor if its priority is sufficiently high.

Abstract: An exemplary embodiment of a method is implemented in a wireless network and is advantageous in that an undesired interim media channel link which would have been used in prior art systems is identified during call setup and avoided. In response to a call request in the wireless network for a call with a first user's wireless subscriber unit, a determination is made if one of a calling home node and a called home node of the first user's wireless subscriber unit should not be used as a node in the media channel such as due to the one node's remote location relative to the rest of the nodes in the media channel. A resulting media channel is established so that the one of the calling home node and the called home node is not part of a path of the media channel thereby minimizing the total distance and delay of the media path.

Abstract: A method and apparatus for providing virtual private network (VPN) connectivity between at least two customer sites. Each of a plurality of PE routers includes at least one access module adapted for connectivity to at least one customer site. The access modules are generated automatically for each PE router associated with a VPN, wherein customer sites, which are associated with said VPN and have an identical export route target (RT) value and import RT value, are connected to a common access module. Otherwise, customer sites associated with the PE router that do not have identical export and import RT values are coupled to their own respective access modules at the PE router. Each access module generates an ingress-forwarding table for routing packetized information between the at least two customer sites.

Abstract: Methods and systems for forwarding packets over Label Switched Paths (LSPs) in a Virtual Private Network (VPN) are implemented within a Layer-2 architecture. A system includes a number of multi-purpose nodes connected by a number of multi-protocol label switching (MPLS) LSP links. Each multi-purpose node contains at least one bridging module (BM) that runs an extension of a bridging protocol (BP) contained in the IEEE 802.1d standard. The BP is used to establish MPSL LSPs between the BMs. The BP then generates a spanning tree using a spanning tree program to establish an optimal number of active LSPs. The remaining LSPs are then set to “inactive.” The BM de-allocates the resources assigned to inactive LSPs and makes the resources available to other active LSPs.