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: A method, system, and computer-readable medium for transmitting voice over multiprotocol label switching is provided. A packet that includes layer 3 and layer 4 headers is received. A label that identifies a label switched path in the packet is inserted, and a stream identifier is generated. The stream identifier is associated with at least a portion of content of the layer 3 and layer 4 headers. The layer 3 and layer 4 headers are removed from the packet, and the stream identifier is inserted into the packet. Additionally, methods, systems, and a computer-readable medium for processing a voice over multiprotocol label switching frame that excludes layer 3 and layer 4 headers are provided.

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: Methods and systems for detecting IP route failure using a request-reply protocol, such as address resolution protocol (ARP), and for dynamically re-routing VoIP sessions in a VoIP device in response to failure of an IP route are disclosed. A plurality of IP routes are established between a first VoIP device and a second VoIP device. VoIP sessions are assigned to the IP routes. ARP is used to detect a failure of an IP route. In response to detecting a failure of at least one IP route, VoIP sessions are rerouted from the failed IP route to an alternate IP route.

Abstract: Methods and systems for per-session traffic rate policing in a media gateway include receiving voice over IP (VoIP) packets at a media gateway where it is determined whether each VoIP packet is associated with an existing VoIP session in the media gateway. A per-session traffic rate policing policy is applied to the packets associated with the existing sessions in the media gateway. In response to determining that a packet violates the per-session traffic rate policing policy, the packet is 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: Methods and systems for measurement-based call admission control in a media gateway are disclosed. A request for establishing a new voice-over-IP (VoIP) call for sending and receiving voice over IP packets in a media gateway is received. The request indicates a required bandwidth for the new call. Bandwidth utilization of at least one Internet protocol (IP) network interface for sending and receiving voice over IP packets in the media gateway is determined. The media gateway determines whether to admit the new VoIP call based on the determined requested bandwidth for the new call and the determined bandwidth utilization for at least one of the IP network interfaces.

Abstract: Methods and systems for automatic denial of service protection in an IP device are disclosed. Packets are received at a network interface of an IP device, the packets being addressed to a network address of the network interface. The packets addressed to the network interface of the IP device are forwarded to a processor in the IP device. The processor determines whether the packets violate a rate-based policing policy of the IP device. In response to determining that the packets violate the rate-based policing policy, source identifying information associated with the packets is added to an access control list in the IP device. Packets matching criteria in the access control list are prevented from being forwarded to the processor in the IP device.

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: Methods and systems for classifying incoming and/or outgoing packets to sessions in a media gateway store session identifiers for active sessions in a media gateway in a memory. Each session identifier is a combination of a local network address, a local port number, a remote network address, and a remote port number for the session. Alternatively, each session identifier is a combination of a local network address and a local port number. An incoming and/or outgoing packet is classified to one of the active sessions by using network address and port number information from the packet to perform a lookup for a corresponding session identifier in the memory.

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: A redundancy protection scheme comprises sending a protection packet from the primary network interface to the secondary network interface, the protection packet having a hardware address of the primary network interface as a source address and a hardware address of the secondary network interface as a destination address. The scheme further comprises determining whether the secondary network interface receives the protection packet from the primary network interface, operating the primary and secondary network interface as active and standby network interface in response to the secondary network interface receiving the protection packet, or operating both the primary and secondary network interface as active network interface in response to the secondary network interface not receiving the protection packet, and providing the hardware address of the active secondary network interface to devices coupled thereto.

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: A method, system, and computer-readable medium for transmitting voice over multiprotocol label switching is provided. A packet that includes layer 3 and layer 4 headers is received. A label that identifies a label switched path in the packet is inserted, and a stream identifier is generated. The stream identifier is associated with at least a portion of content of the layer 3 and layer 4 headers. The layer 3 and layer 4 headers are removed from the packet, and the stream identifier is inserted into the packet. Additionally, methods, systems, and a computer-readable medium for processing a voice over multiprotocol label switching frame that excludes layer 3 and layer 4 headers are provided.

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 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.