Abstract: Concepts and technologies disclosed herein are directed to deadlock-free traffic rerouting in software-defined networking (“SDN”) networks. According to one aspect of the concepts and technologies disclosed herein, a centralized SDN controller can determine that a packet flow along a path within at least a portion of a network is to be rerouted from the path to a new path. The centralized SDN controller can initiate a reroute of the packet flow to the new path. The centralized SDN controller can request a bandwidth for the new path. The bandwidth can be determined such that bandwidth oversubscription on the new path is avoided. In response to the packet flow settling on the new path, the centralized SDN controller can adjust a requested bandwidth of the packet flow to a desired value to complete the reroute of the packet flow from the path to the new path.

Abstract: Concepts and technologies disclosed herein are directed to deadlock-free traffic rerouting in software-defined networking (“SDN”) networks. According to one aspect of the concepts and technologies disclosed herein, a centralized SDN controller can determine that a packet flow along a path within at least a portion of a network is to be rerouted from the path to a new path. The centralized SDN controller can initiate a reroute of the packet flow to the new path. The centralized SDN controller can request a bandwidth for the new path. The bandwidth can be determined such that bandwidth oversubscription on the new path is avoided. In response to the packet flow settling on the new path, the centralized SDN controller can adjust a requested bandwidth of the packet flow to a desired value to complete the reroute of the packet flow from the path to the new path.

Abstract: The claimed subject matter is directed to novel methods and systems for a network topology wherein an Internet Protocol (IP) network is partially integrated and enhanced with a relatively small number of Software Defined Network (SDN)-Openflow (SDN-OF) enabled network devices to provide a resilient network that is able to quickly recover from a network failure and achieves post-recovery load balancing while minimizing cost and complexity. The SDN-OF Controller, or a management node, determines such a minimum set of SDN-OF enabled devices and establishes IP tunnels to route traffic from nodes affected by failure to designated SDN-OF switches and finally to the final destination without looping back to the failed link or node. By combining SDN-OF enabled switches with IP nodes such as routers, a novel network architecture and methods are described herein that allows for ultra-fast and load balancing-aware failure recovery of the data network.

Abstract: Concepts and technologies disclosed herein are directed to deadlock-free traffic rerouting in software-defined networking (“SDN”) networks have been disclosed herein. According to one aspect of the concepts and technologies disclosed herein, a centralized SDN controller can determine that a packet flow along a path within at least a portion of a network is to be rerouted from the path to a new path. The centralized SDN controller can initiate a reroute of the packet flow to the new path. The centralized SDN controller can request a bandwidth for the new path. The bandwidth can be determined such that bandwidth oversubscription on the new path is avoided. In response to the packet flow settling on the new path, the centralized SDN controller can adjust a requested bandwidth of the packet flow to a desired value to complete the reroute of the packet flow from the path to the new path.

Abstract: A router may include a central processing unit-based line card storing a forwarding table that includes a first set of entries, a network processing unit-based line card storing a partial forwarding table that includes a second set of entries comprising a subset of the first set of entries, where the second set of entries comprises entries that are most utilized by a plurality of line cards of the router, and a route controller for updating the second set of entries to comprise the entries that are the most utilized. The network processing unit-based line card may forward a packet when an entry in the partial forwarding table matches the packet and may forward the packet to the central processing unit-based line card to forward the packet when there is no entry in the partial forwarding table of the network processing-unit based line card that matches the packet.

Abstract: A network controller comprising a processor configured to obtain topology information of a network, wherein the topology information indicates a plurality of non-software-defined networking (non-SDN) network elements (NEs) interconnected by a plurality of links in the network, analyze each non-SDN NE according to the topology information to determine whether the non-SDN NE is a candidate NE for establishing a backup tunnel to protect a single-link failure at one of the plurality of links, and select a plurality of target NEs from the candidate NEs to protect against all single link-failures in the network, and a transmitter coupled to the processor and configured to send a first message to a first of the target NEs to dynamically enable software-defined networking (SDN) functionalities at the first target NE in order to facilitate single-link failure protection in the network.

Abstract: A router may include a central processing unit-based line card storing a forwarding table that includes a first set of entries, a network processing unit-based line card storing a partial forwarding table that includes a second set of entries comprising a subset of the first set of entries, where the second set of entries comprises entries that are most utilized by a plurality of line cards of the router, and a route controller for updating the second set of entries to comprise the entries that are the most utilized. The network processing unit-based line card may forward a packet when an entry in the partial forwarding table matches the packet and may forward the packet to the central processing unit-based line card to forward the packet when there is no entry in the partial forwarding table of the network processing-unit based line card that matches the packet.

Abstract: Given a large number of traffic matrices, the matrices are divided into M clusters, where M is a relatively small number. A load-balancing apparatus is implemented as an application over the SDN controller. Such an application is executed to configure and reconfigure the switches to achieve near-optimal load balancing, even when the traffic load changes. For each cluster, a near-optimal explicit routing configuration is determined. The combination of explicit routing (cluster-specific) and destination-based routing (same for all clusters) is used to achieve near-optimal load balancing for each cluster.

Abstract: A controller having an application optimally routing traffic to balance fluctuating traffic loads in a SDN network. A processor is configured to control the data plane to establish routing through the plurality of routers, wherein the processor is configured to establish hybrid routing comprising both explicit routing and destination-based routing. The processor utilizes a set of traffic matrices representing the fluctuating traffic load over time. A destination-based multi-path routing algorithm is configured to improve load balancing of the traffic load based on the set of representative traffic matrices. The destination based routing is calculated based on linear programming. The processor comprises a traffic categorization algorithm configured to identify a set of key flows, wherein the processor is configured to explicitly route the set of key flows.

Abstract: A network controller comprising a processor configured to obtain topology information of a network, wherein the topology information indicates a plurality of non-software-defined networking (non-SDN) network elements (NEs) interconnected by a plurality of links in the network, analyze each non-SDN NE according to the topology information to determine whether the non-SDN NE is a candidate NE for establishing a backup tunnel to protect a single-link failure at one of the plurality of links, and select a plurality of target NEs from the candidate NEs to protect against all single link-failures in the network, and a transmitter coupled to the processor and configured to send a first message to a first of the target NEs to dynamically enable software-defined networking (SDN) functionalities at the first target NE in order to facilitate single-link failure protection in the network.

Abstract: The claimed subject matter is directed to novel methods and systems for a network topology wherein an Internet Protocol (IP) network is partially integrated and enhanced with a relatively small number of Software Defined Network (SDN)-Openflow (SDN-OF) enabled network devices to provide a resilient network that is able to quickly recover from a network failure and achieves post-recovery load balancing while minimizing cost and complexity. The SDN-OF Controller, or a management node, determines such a minimum set of SDN-OF enabled devices and establishes IP tunnels to route traffic from nodes affected by failure to designated SDN-OF switches and finally to the final destination without looping back to the failed link or node. By combining SDN-OF enabled switches with IP nodes such as routers, a novel network architecture and methods are described herein that allows for ultra-fast and load balancing-aware failure recovery of the data network.

Abstract: Given a large number of traffic matrices, the matrices are divided into M clusters, where M is a relatively small number. A load-balancing apparatus is implemented as an application over the SDN controller. Such an application is executed to configure and reconfigure the switches to achieve near-optimal load balancing, even when the traffic load changes. For each cluster, a near-optimal explicit routing configuration is determined. The combination of explicit routing (cluster-specific) and destination-based routing (same for all clusters) is used to achieve near-optimal load balancing for each cluster.

Abstract: The claimed subject matter is directed to novel methods and systems for a network topology wherein an IP network is partially integrated and enhanced with a relatively small number of SDN-OF enabled network devices to provide a resilient network that is able to quickly recover from a network failure and achieves post-recovery load balancing while minimizing cost and complexity. By combining SDN-OF enabled switches with traditional IP nodes such as routers, a novel network architecture and methods are described herein that allows for ultra-fast and load balancing-aware failure recovery of the data network.

Abstract: A controller having an application optimally routing traffic to balance fluctuating traffic loads in a SDN network. A processor is configured to control the data plane to establish routing through the plurality of routers, wherein the processor is configured to establish hybrid routing comprising both explicit routing and destination-based routing. The processor utilizes a set of traffic matrices representing the fluctuating traffic load over time. A destination-based multi-path routing algorithm is configured to improve load balancing of the traffic load based on the set of representative traffic matrices. The destination based routing is calculated based on linear programming. The processor comprises a traffic categorization algorithm configured to identify a set of key flows, wherein the processor is configured to explicitly route the set of key flows.

Abstract: Hybrid security architecture (HSA) provides a platform for middlebox traversal in the network. The HSA decouples the middlebox control from network forwarding. More specifically, such embodiments may receive a data packet having a packet header including an Ethernet header identifying source and destination addresses in the network. A traffic type of the data packet is determined. Then, layer-2 forwarding information, which encodes a set of non-forwarding network service provider middleboxes in the network to be traversed by the data packet, is determined based on the traffic type. The layer-2 forwarding information is inserted into the Ethernet header and the data packet is forwarded into the network. The data packet will then traverse, according to the layer-2 forwarding information, a sequence of the middleboxes in the network, wherein at least one non-forwarding network service will be provided by each of the middleboxes to the data packet in a sequence.

Abstract: Load balancing is performed in a network using flow-based routing. For example, upon detection of a big flow, one or more alternative paths from a source host to a destination host in the network may be discovered by probing the network and generating, for each of the one or more alternative paths, an association of the packet header information of the big flow to an alternative path discovered using results of probing the network. Upon congestion in a path currently being used by the big flow, an alternative path that is not congested is selected from the one or more discovered alternative paths. The packet header information of the big flow is altered using the generated association of the packet header information to the selected alternative path such that the big flow will be transmitted using the selected alternative path.

Abstract: Hybrid security architecture (HSA) provides a platform for middlebox traversal in the network. The HSA decouples the middlebox control from network forwarding. More specifically, such embodiments may receive a data packet having a packet header including an Ethernet header identifying source and destination addresses in the network. A traffic type of the data packet is determined. Then, layer-2 forwarding information, which encodes a set of non-forwarding network service provider middleboxes in the network to be traversed by the data packet, is determined based on the traffic type. The layer-2 forwarding information is inserted into the Ethernet header and the data packet is forwarded into the network. The data packet will then traverse, according to the layer-2 forwarding information, a sequence of the middleboxes in the network, wherein at least one non-forwarding network service will be provided by each of the middleboxes to the data packet in a sequence.

Abstract: Load balancing is performed in a network using flow-based routing. For example, upon detection of a big flow, one or more alternative paths from a source host to a destination host in the network may be discovered by probing the network and generating, for each of the one or more alternative paths, an association of the packet header information of the big flow to an alternative path discovered using results of probing the network. Upon congestion in a path currently being used by the big flow, an alternative path that is not congested is selected from the one or more discovered alternative paths. The packet header information of the big flow is altered using the generated association of the packet header information to the selected alternative path such that the big flow will be transmitted using the selected alternative path.

Abstract: A scheme to achieve fast recovery from SRLG failures in the IP layer is described. An exemplary scheme, called multi-section shortest path first (“MSSPF”), builds on the idea of IP Fast Reroute (“IPFRR”), guarantees 100% recovery of SRLG failures and causes no dead loops.

Abstract: For a survivable portion of a network, a backup port for a first router of the survivable network, to reach a destination node in the event of a single node failure, may be determined by (a) accepting a routing path graph having the destination node, wherein the routing path graph includes one or more links terminated by one or more primary ports of the first router; and (b) for each router of at least a part of the routing path graph, (1) assuming that the current router is removed, defining (A) a first part of the routing path graph including the destination node, and (B) a second part of the routing path graph separated from the first part wherein the second part defines one or more sub-graphs, and (2) determining the backup port for the first router by examining at least one of the one or more sub-graphs to find a link to the first part of the routing path graph.