Abstract: Systems and methods are disclosed for extending digital signal processor (DSP) capability of existing media gateway devices. A system includes a media gateway device, which has a first plurality of voice server cards. Each voice server card comprises a first controller, a first communications interface, and at least one first DSP configured to implement at least one first coder/decoder (codec). The system further includes a communications switch and at least one external DSP server. The external DSP server comprises a second plurality of voice server cards, which each comprise a second controller, a second communications interface, and at least one second DSP configured to implement at least one second codec. The at least one external DSP server is in communication with the media gateway device via the communications switch.

Abstract: Systems and methods are disclosed for extending digital signal processor (DSP) capability of existing media gateway devices. A system includes a media gateway device, which has a first plurality of voice server cards. Each voice server card comprises a first controller, a first communications interface, and at least one first DSP configured to implement at least one first coder/decoder (codec). The system further includes a communications switch and at least one external DSP server. The external DSP server comprises a second plurality of voice server cards, which each comprise a second controller, a second communications interface, and at least one second DSP configured to implement at least one second codec. The at least one external DSP server is in communication with the media gateway device via the communications switch.

Abstract: The subject matter described herein includes methods, systems, and computer program products for storing communication session information at a network interface module. One method described herein includes receiving a plurality of RTCP packets associated with a communication session at a network interface module. RTCP information is extracted from at least one of the packets. The extracted RTCP information is stored in memory local to the network interface module.

Abstract: The subject matter described herein includes methods, systems, and computer program products for storing communication session information at a network interface module. One method described herein includes receiving a plurality of RTCP packets associated with a communication session at a network interface module. RTCP information is extracted from at least one of the packets. The extracted RTCP information is stored in memory local to the network interface module.

Abstract: The subject matter described herein includes methods, systems, and computer program products for storing communication session information at a network interface module. One method described herein includes receiving a plurality of RTCP packets associated with a communication session at a network interface module. RTCP information is extracted from at least one of the packets. The extracted RTCP information is stored in memory local to the network interface module.

Abstract: Methods, systems, and computer program products for implementing automatic protection switching for media packets, such as ATM cells or IP packets that carry media content, in a device that includes an Ethernet switching fabric are disclosed. According to one method, first and second packet network interfaces of the device are configured to function as working and protection APS interfaces. At least one of a media processing resource and an Ethernet switch fabric of the device are configured to replicate egress media packets from the media processing resource to the working and protection APS interfaces. Egress media packets from the media processing resource are forwarded to the working and protection APS interfaces via the switch fabric. Ingress media packets received at the working APS interface are forwarded to the media processing resource via the Ethernet switch fabric. Media packets received at the protection APS interface are discarded.

Abstract: The subject matter described herein includes methods, systems, and computer program products for load balanced and symmetric SPF path computations for VoIP traffic engineering. One method includes advertising an output interface cost in a first direction over a first network segment between a source IP device and a destination IP device that is different from an output interface cost in advertised in a second direction over the first network segment. A plurality of available network paths between the source IP device and the destination IP device is identified. A path cost is calculated for each of the available network paths from the source IP device to the destination IP device. Calculating a path cost includes, for paths that include the first network segment, substituting the output interface cost advertised in the first direction with the output interface cost advertised in the second direction. The path costs are ranked based on the calculated costs. A lowest cost path is selected from the ranked paths.

Abstract: The subject matter described herein includes methods, systems, and computer program products for source-aware IP routing at a media gateway. According to one aspect, a method for source-aware IP routing at a media gateway is provided. The method includes providing a packet including a layer 3 source address and a layer 3 destination address at a media gateway having a source-aware routing table. Using the destination address included in the packet, at least one entry corresponding to the destination address is located in the source-aware routing table, where the located entry contains at least a portion of a source IP address, at least a portion of a destination IP address and routing information including an interface identifier and a next hop identifier. From among the at least one located entry corresponding to the destination IP address information, at least one entry corresponding to the source IP address included in the packet is located.

Abstract: The subject matter described herein includes methods, systems, and computer program products for transporting ATM cells in a device having an Ethernet switching fabric. According to one method, at least one ingress ATM cell is received at an ATM network interface of a device having an Ethernet switching fabric. Next, the connection associated with which the ingress ATM cell is identified. The ATM cell is encapsulated in Ethernet frame addressed to a media processing resource associated with the connection. The Ethernet frame is forwarded to the media processing resource across an Ethernet switching fabric.

Abstract: Method, systems, and computer program products for voice over IP (VoIP) traffic engineering and path resilience using media gateway and associated next-hop routers are provided. In one example, a media gateway includes multiple media processing hosts and a multiple network interfaces separate from the media processing hosts. At least one of the media processing hosts is reachable via at least two of the network interfaces. Next-hop routers associated with the network interfaces advertise reachability information regarding the media processing hosts to routers in the network. The next-hop routers also participate in network routing protocols to form multiple paths between the media gateway and a remote media gateway. Costs may be assigned to associations between the media processing hosts and the next-hop routers for traffic engineering purposes.

Abstract: Methods, systems, and computer program products for implementing link redundancy in a media gateway are provided according to one method, a media gateway link protection group is provisioned to associate with a common VLAN a common virtual local area network (VLAN) primary and secondary links associated with at least one line card in a media gateway. The primary and secondary links are connected using a cross connection between ports associated with the at least one line card. At run time, traffic is automatically bridged between the primary and secondary links using the common VLAN and the cross connection.

Abstract: The subject matter described herein includes methods, systems, and computer program products for load balanced and symmetric SPF path computations for VoIP traffic engineering. One method includes advertising an output interface cost in a first direction over a first network segment between a source IP device and a destination IP device that is different from an output interface cost in advertised in a second direction over the first network segment. A plurality of available network paths between the source IP device and the destination IP device is identified. A path cost is calculated for each of the available network paths from the source IP device to the destination IP device. Calculating a path cost includes, for paths that include the first network segment, substituting the output interface cost advertised in the first direction with the output interface cost advertised in the second direction. The path costs are ranked based on the calculated costs. A lowest cost path is selected from the ranked paths.

Abstract: The subject matter described herein includes methods, systems, and computer program products for load balanced and symmetric SPF path computations for VoIP traffic engineering. One method includes advertising an output interface cost in a first direction over a first network segment between a source IP device and a destination IP device that is different from an output interface cost in advertised in a second direction over the first network segment. A plurality of available network paths between the source IP device and the destination IP device is identified. A path cost is calculated for each of the available network paths from the source IP device to the destination IP device. Calculating a path cost includes, for paths that include the first network segment, substituting the output interface cost advertised in the first direction with the output interface cost advertised in the second direction. The path costs are ranked based on the calculated costs. A lowest cost path is selected from the ranked paths.

Abstract: Methods, systems, and computer program products for multipath Shortest-Path-First (SPF) computations and distance-based interface selection for VoIP traffic are disclosed. According to one method, a multi-path router instance associated with a plurality of network interfaces in a source IP device is provided. A cost is assigned to each of a plurality of internal segments between the multi-path router instance and the network interfaces associated with the multi-path router instance. An aggregate cost is calculated for each of a plurality of traffic paths originating at the multi-path router instance in the source IP device and extending through each of the network interfaces associated with the multi-path router instance to a destination IP device in the network. A list of IP paths is generated, and the paths in the list are ranked based on the calculated cost. Traffic is sent from the source IP device over at least one of the paths in the list.

Abstract: Methods, systems, and computer program products for throttling network address translation (NAT) learning traffic in a voice over IP device are disclosed. According to one method, a plurality of media packets associated with a media session are received at a voice over IP device. A NAT learning throttling filter is applied to select the subset of the packets to be used for NAT learning and thereby limit the number of received media packets to be used for NAT learning. NAT learning is performed for the session using the packets selected by the NAT learning throttling filter.

Abstract: The subject matter described herein includes methods, systems, and computer program products for source-aware IP routing at a media gateway. According to one aspect, a method for source-aware IP routing at a media gateway is provided. The method includes providing a packet including a layer 3 source address and a layer 3 destination address at a media gateway having a source-aware routing table. Using the destination address included in the packet, at least one entry corresponding to the destination address is located in the source-aware routing table, where the located entry contains at least a portion of a source IP address, at least a portion of a destination IP address and routing information including an interface identifier and a next hop identifier. From among the at least one located entry corresponding to the destination IP address information, at least one entry corresponding to the source IP address included in the packet is located.

Abstract: Methods and systems for per-session dynamic management of media gateway resources are disclosed. According to one method, the logical and physical resources in a media gateway are divided and dynamically managed at the Transport Layer (i.e. OBI Layer 4), which results in finer granularity than managing such resources statically at the Data Link Layer (i.e. OBI Layer 2) or Network Layer (i.e. OBI Layer 3). Voice-processing resources provided by voice server cards may be pooled into a common pool available to all external networks. For each new call/session, the dynamic resource manager of the media gateway dynamically allocates a voice chip from the pooled voice processing resources, and assigns a logical resource identifier (e.g. a local IP and local UDP pair) to the session. When a network interface card receives incoming voice packets, it checks the destination IP and UDP and optionally the source IP and UDP to find out, and forward voice packets to, the voice chip assigned to the session.

Abstract: Methods and systems for per-session NAT learning and firewall filtering are disclosed. Media packets associated with a call/session are received and processed at a media gateway. For the first few received media packets associated with a session, the media gateway uses various unique methods to learn the actual source IP address and UDP port assigned to the remote communication terminal by its customer-premises Network Address Translators (NATs) to the media flows of the current session. After the remote IP and UDP are learned, the media gateway reconfigures its firewall filtering function to check both the dynamically learned remote IP and UDP and the locally assigned IP and UDP of the current session. The per-session NAT learning function removes reachability issues in VoIP deployment, and the per-session firewall filtering function enhances security protection in VoIP deployment.

Abstract: The subject matter described herein includes methods, systems, and computer program products for storing communication session information at a network interface module. One method described herein includes receiving a plurality of RTCP packets associated with a communication session at a network interface module. RTCP information is extracted from at least one of the packets. The extracted RTCP information is stored in memory local to the network interface module.

Abstract: Methods and systems for providing voice over IP traffic engineering and path resilience using a network-aware media gateway are provided. In a media gateway, voice over IP hosts are assigned a first set of IP addresses. Network interfaces in the media gateway are assigned a second set of IP addresses that differ from the first set of IP addresses. Per-interface routers advertise reachability information from at least one of the voice over IP hosts via multiple interfaces and participate in network routing protocols to generate per interface routing tables. Voice over IP path lists may be generated based on the per interface routing tables. Internal costs may be assigned to the associations between the voice over IP hosts and the interfaces based on traffic engineering criteria.