Abstract: A method implemented by a switch in a Software Defined Networking (SDN) network to trace packets in the SDN network, where the switch includes a packet processing pipeline. The method includes receiving a first packet, determining, at a first flow table of the packet processing pipeline, whether the first packet is to be traced, punting a copy of the first packet to an SDN controller and directing the first packet to a second flow table of the packet processing pipeline in response to a determination at the first flow table that the first packet is to be traced.

Abstract: Methods for tracing a packet in a pipeline comprising a set of tables, in an SDN using OpenFlow. The packet comprises a trace bit, and is provided with a TTL value. A first network node indicates to a second network node to have each flow table decrement the TTL value by 1, based upon the trace bit. The first network node initially sets the TTL to be 1, and then sends the packet to a first table in the second network node. The first network node receives the packet, from another table in the set, and for every remaining table, and one table at a time: a) increments the TTL value by 1, and b) repeats the sending, and the receiving, until a last table is reached or a criterion is met. The first network node then indicates a route followed by the packet.

Abstract: A method is implemented by a network device where the method performs a trace flow process in a packet processing pipeline of the network device. The packet processing pipeline includes a trace table and a forward table. The method encompasses forwarding a trace packet to the trace table, forwarding a copy of the trace packet to a trace analyzer in response to determining that a trace bit is set in the trace packet, forwarding the trace packet to the forward table, and determining a next stage of the packet processing pipeline based on trace packet meta data and a value stored in a trace register.

Abstract: A method is implemented by a switch in a software defined networking (SDN) network managed by a controller to achieve hitless resynchronization during a controller upgrade. The method includes installing an upgraded set of flow entries so that a packet processing pipeline of the switch includes both a non-upgraded set of flow entries and the upgraded set of flow entries, processing non-tunneled packets using the non-upgraded set of flow entries, processing tunneled packets that have a tunnel upgrade status indicator set in a tunnel header using the non-upgraded set of flow entries, while processing tunneled packets that do not have a tunnel upgrade status indicator set in a tunnel header using the upgraded set of flow entries, and processing non-tunneled packets using the upgraded set of flow entries after all switches managed by the controller have installed upgraded flow entries.

Abstract: A method is implemented by a switch in a software defined networking (SDN) network to trace packets in a packet processing pipeline of the switch. The method includes creating a copy of a received packet to function as a trace packet. The method further includes, at each of one or more subsequent flow tables that the trace packet traverses, appending an identifier of that flow table to a recorded route of the trace packet and resubmitting the trace packet to that flow table to be processed without packet tracing. The method further includes sending, at an egress table, the trace packet to a controller along with the recorded route of the trace packet.

Abstract: A method implemented by a first controller in a software defined networking (SDN) network to monitor a health of a second controller, where the first controller and the second controller are part of a cluster of controllers, where controllers in the cluster communicate with switches over an in-band network, and where controllers in the cluster communicate with each other over an out-of-band network. The method includes sending a first control message to a switch over the in-band network in response to a determination that the second controller cannot be reached over the out-of-band network, where the first control message includes a health check request message and an instruction for the switch to send the health check request message to the second controller, and where the switch is a designated switch that has a control channel connection to the first controller and the second controller over the in-band network.

Abstract: A method implemented by a switch in a Software Defined Networking (SDN) network to trace packets in the SDN network, where the switch includes a packet processing pipeline. The method includes receiving a first packet, determining, at a first flow table of the packet processing pipeline, whether the first packet is to be traced, punting a copy of the first packet to an SDN controller and directing the first packet to a second flow table of the packet processing pipeline in response to a determination at the first flow table that the first packet is to be traced.

Abstract: A software defined networking (SDN) system includes a switch, a service function chain (SFC) proxy, and a controller communicatively coupled to the SFC proxy and the switch. The controller is configured to obtain a translation rule for a SFC encapsulation provided by the SFC proxy, responsive to obtaining the translation rule transmit one or more instructions to the switch to program the switch to translate packets belonging to a flow associated with the SFC encapsulation according to the translation rule and to forward the packets belonging to the flow associated with the SFC encapsulation to a service function (SF) in a manner that causes the packets belonging to the flow associated with the SFC encapsulation to bypass the SFC proxy, and transmit an indication to the SFC proxy that the packets belonging to the flow associated with the SFC encapsulation are to bypass the SFC proxy.

Abstract: Exemplary embodiments include methods and/or procedures for handling messages from one or more data-plane nodes (DPNs) to a plurality of controller nodes configured in a cluster, comprising: receiving a message from a DPN; tagging the message with an incarnation identifier (IID) associated with the DPN; and performing HD handling of the tagged message, which includes comparing a value of the IID of the tagged message with a value of a global IID associated with the DPN, discarding the tagged message if the value of the IID of the tagged message is less than the value of the global IID, and processing the tagged message if the value of the IID of the tagged message is not less than the value of the global IID. Exemplary embodiments also include controller nodes, controller clusters, and computer-readable media embodying operations of the exemplary methods and/or procedures.

Abstract: A system for tracing packets in a Software Defined Networking (SDN) network. The system includes a switch and an SDN controller communicatively coupled to the switch. The SDN controller is configured to program a packet processing pipeline of the switch to cause the switch to determine, at a first flow table of the packet processing pipeline, whether a packet is a trace packet that was recirculated based on content of a first field associated with the packet and in response to a determination that the packet is a trace packet that was recirculated, set a first field associated with the packet to indicate that tracing is disabled for the packet, set a second field associated with the packet to indicate that tracing is enabled for the packet, determine a flow table of the packet processing pipeline from which the packet was recirculated, and direct the packet to that flow table.

Abstract: A method is implemented by a switch in a Software Defined Networking (SDN) network to trace packets, where the switch includes a packet processing pipeline that includes a plurality of flow tables. The method includes receiving a packet, determining, at a first flow table of the packet processing pipeline, whether the packet is a trace packet that was recirculated based on content of a first field associated with the packet, and in response to a determination that the packet is trace packet that was recirculated, setting a first field associated with the packet to indicate that tracing is disabled for the packet, setting a second field associated with the packet to indicate that tracing is enabled for the packet, determining a flow table of the packet processing pipeline from which the packet was recirculated, and directing the packet to the flow table from which the packet was recirculated.

Abstract: A method is implemented by a control plane device in a Software Defined Networking (SDN) network to configure a data plane device in the SDN network to perform network address translation (NAT) for a flow so that the flow can bypass a NAT device. The method includes receiving a translation rule for the flow from the NAT device, configuring the data plane device to steer the flow such that the flow bypasses the NAT device, configuring the data plane device to perform NAT for the flow according to the translation rule for the flow, and transmitting an indication to the NAT device that the flow is to bypass the NAT device.

Abstract: A method is implemented by a network device functioning as a switch in a software defined networking (SDN) network to detect data plane loops in the SDN network. The method includes receiving a packet, setting a value of a packet register associated with the packet to an initial loop count value, performing an arithmetic operation on the packet register to update the value of the packet register to an updated loop count value when the packet is to be resubmitted to a current flow table or a previous flow table of a packet processing pipeline of the switch, and determining that the packet is in a data plane loop in response to a determination that the updated loop count value is an invalid value.

Abstract: A method implemented by a network device to reduce bandwidth and compute resources needed by a controller of a software defined networking (SDN) network by distributing monitoring of nodes connected to data plane nodes (DPNs) in an SDN network. The method determines whether a received response message from a node indicates proper operation, inserts parameters of the received response message into a template for a stateful request message, and sends the stateful request message to the node.

Abstract: A method implemented by a switch in a software defined networking (SDN) network to monitor a service node communicatively coupled to the switch. The method includes generating a first flow entry that matches packets received from the service node, generating a second flow entry that matches packet received from the service node, wherein the second flow entry has a priority that is lower than a priority of the first flow entry, removing the first flow entry and transmitting a flow removed message to an SDN controller in response to a determination that the first flow entry has timed out, maintaining a statistic associated with the second flow entry, and transmitting a statistics trigger event message to the SDN controller in response to a determination that the statistic associated with the second flow entry exceeds a threshold value.

Abstract: A method is performed by a network device acting as a controller in a software defined networking (SDN) network. The method detects control path loops in the SDN network. The method includes receiving a Packet-In message from a switch, where the Packet-In message includes a packet. The method further includes determining a packet identifier associated with the packet, determining a key based on the packet identifier associated with the packet, determining whether an entry associated with the key exists in a loop detection cache, updating a counter value associated with the entry in response to determining that the entry associated with the key exists in the loop detection cache, and determining that the packet is in a control path loop in response to determining that the counter value associated with the entry reaches a threshold value.

Abstract: A method is implemented by a network device to reduce bandwidth and compute resources needed by the controller of a software defined networking (SDN) controller by distributing monitoring of virtual network functions (VNFs) to data plane nodes (DPNs) in a SDN network. The method includes receiving a monitoring request from the SDN controller to monitor a VNF, receiving a byte sequence from the SDN controller for the VNF, and generating flow table entries for monitoring the VNF by matching the byte sequence with monitoring response messages from the VNF.

Abstract: A method implemented by a first switch in a software defined networking (SDN) network to monitor a tunnel between the first switch and a second switch in the SDN network. The method includes generating a first flow entry that matches packets received over the tunnel, generating a second flow entry that matches packet received over the tunnel, where the second flow entry has a priority that is lower than a priority of the first flow entry, removing the first flow entry and transmitting a flow removed message to an SDN controller in response to a determination that the first flow entry has timed out, maintaining a statistic associated with the second flow entry, and transmitting a statistics trigger event message to the SDN controller in response to a determination that the statistic associated with the second flow entry exceeds a threshold value.

Abstract: A method is implemented by a network device functioning as a switch in a software defined networking (SDN) network to detect data plane loops in the SDN network. The method includes receiving a packet, setting a value of a packet register associated with the packet to an initial loop count value, performing an arithmetic operation on the packet register to update the value of the packet register to an updated loop count value when the packet is to be resubmitted to a current flow table or a previous flow table of a packet processing pipeline of the switch, and determining that the packet is in a data plane loop in response to a determination that the updated loop count value is an invalid value.

Abstract: A method is implemented by a control plane device in a Software Defined Networking (SDN) network to configure a data plane device in the SDN network to perform network address translation (NAT) for a flow so that the flow can bypass a NAT device. The method includes receiving a translation rule for the flow from the NAT device, configuring the data plane device to steer the flow such that the flow bypasses the NAT device, configuring the data plane device to perform NAT for the flow according to the translation rule for the flow, and transmitting an indication to the NAT device that the flow is to bypass the NAT device.