Abstract: Disclosed are devices, systems and methods for load balancing and operation, administration and maintenance (OAM) in service function chaining using the multiprotocol label switching (MPLS) forwarding plane. In some implementations, a packet processing method includes processing a network packet comprising a plurality of labels based on presence of an indicator label in the plurality of labels such that in case that the indicator label is present in the network packet, the indicator label is used to determine a first destination of a payload of the network packet, and in case that the indicator label is not present in the network packet, the payload is passed to a second destination selected based on a service function indicator in the plurality of labels.

Abstract: Techniques are described for generating and using an extended Bi-directional Forwarding Detection (BFD) control packet in a network. The extended BFD control packet includes a control message that includes a BFD session information, an identifier associated with the device sending the BFD control packet, and a payload part. The extended BFD control packet may be used to perform packet loss and/or packet delay related measurements.

Abstract: Residence time is a variable part of the propagation delay of the packet. Information about the propagation delay for each transient node can be used as performance metric to calculate the Traffic Engineered route that can conform to delay and delay variation requirements. In an exemplary embodiment, a computing device uses special test packets to measure residence time. The computing device calculates routes to direct special test packets to one or more nodes. A node may calculate the residence time metric, such as a residence time variation (RTV), or residence time (RT) per ordered set of ingress and egress interfaces of the node. The computing device may also collect the residence time metric per test set from each node and may use this information to calculate the Test Engineered route.

Abstract: A method of operation of a Multiprotocol Label Switching network involves, in an active node of the network, receiving a first data packet from a source node and forwarding the first data packet to a destination node. At the same time, the active node measures a residence time of the first data packet in the active node. The active node then sends a further data packet containing residence time information.

Abstract: Techniques are described for performing error performance measurement in a packet data communication network such as a packet switching network (PSN). An example method of error performance measurement includes determining, upon expiration of a time period, that a number of one or more test packets received by the first device during the time period is less than an expected number of test packets, where the one or more test packets are received by the first device from the second device in a packet data communication network, and triggering, based on the determining, an error performance measurement that includes evaluating a type of failure for the time period and evaluating one or more types of failures for one or more consecutive time periods that immediately precede the time period.

Abstract: Techniques are described for generating and using an extended Bi-directional Forwarding Detection (BFD) control packet with lightweight authentication in a network. The extended BFD control packet includes a BFD control packet, an identifier associated with the device sending the extended BFD control packet, and a payload that includes information related to the requested lightweight authentication. The extended BFD control packet may be used to perform authentication.

Abstract: A method of exposing a maximum segment identifier depth (MSD) value of the network device is described. The method comprises transmitting to a centralized controller an attribute Type Length Value (TLV). A type of the attribute TLV includes a type of a maximum segment identifier depth (MSD) indicating that the MSD is a link MSD, a length of the attribute TLV includes a length of the MSD, and a value of the attribute TLV includes the MSD, which is a maximum number of segment routing (SR) labels supported at a link of the network node. The centralized controller is to use the attribute TLV to compute an SR tunnel with one or more SR labels, a label stack depth of the SR tunnel does not exceed the MSD, and the SR labels are used for steering a packet through an SR network.

Abstract: Techniques are described for performing error performance measurement in a packet data communication network such as a packet switching network (PSN). An example method of error performance measurement includes determining, upon expiration of a time period, that a number of one or more test packets received by the first device during the time period is less than an expected number of test packets, where the one or more test packets are received by the first device from the second device in a packet data communication network, and triggering, based on the determining, an error performance measurement that includes evaluating a type of failure for the time period and evaluating one or more types of failures for one or more consecutive time periods that immediately precede the time period.

Abstract: A method is implemented by a network device to establish a bidirectional forwarding detection (BFD) session with a defined return path to enable detection of data plane failures between an active node and a passive node in a network where a forward path and a reverse path between the active node and the passive node are not co-routed. The method includes receiving a label switched path (LSP) ping including a BFD discriminator type length value (TLV) of the active node and a return path TLV describing a return path to the active node. The BFD discriminator of the active node and a BFD discriminator of the passive node are associated with the BFD session. The return path is associated with the BFD session between the active node and the passive node, and BFD control packets are sent to the active node using the return path to detect a failure on the return path.

Abstract: Techniques are described for generating and using an extended Bi-directional Forwarding Detection (BFD) control packet in a network. The extended BFD control packet includes a control message that includes a BFD session information, an identifier associated with the device sending the BFD control packet, and a payload part. The extended BFD control packet may be used to perform packet loss and/or packet delay related measurements.

Abstract: The disclosed techniques can collect and transport telemetry information on-path when a packet of a service flow traverses a communication network. The collected telemetry information can be analyzed to identify potential issues experienced by a user of a service and simplify the association of data with the service. Thus, apparatuses, methods, computer readable media, and systems are disclosed for an on-path collection and transportation of telemetry information in a communication network.

Abstract: A method is executed by a network device implementing a control-client to configure a session- sender to perform a test to determine whether differentiated services code point (DSCP) and explicit congestion notification (ECN) are modified in a single test session in a forward direction and a reverse direction between the session-sender and a session-reflector. Multiple DSCP and ECN are tested using the single test session. The method includes receiving a server greeting message from a server including characteristics of the session-reflector, determining whether the session-reflector supports use of multiple DSCP in the single test session, setting a set-up- response message to indicate DSCP and ECN testing, and determining whether the session- reflector supports DSCP and ECN monitoring.

Abstract: A method is executed by a network device implementing a session-sender to perform a test to determine whether differentiated services code point (DSCP) and explicit congestion notification (ECN) are modified in a single test session in a forward direction and a reverse direction between the session-sender and a session-reflector, where multiple DSCP and ECN are tested using the single test session. The method includes determining a first initial forward DSCP and ECN, generating a first test packet including the first initial forward DSCP and ECN, and sending the first test packet to the session-reflector in the single test session. The method further includes determining a second initial forward DSCP and ECN, generating a second test packet including the second initial forward DSCP and ECN, and sending the second test packet to the session-reflector in the single test session.

Abstract: A packet communication method that generates a header that includes information to route a packet through a ring communication network is described. The header can include a target node identifier that identifies a target node to which the packet is to travel, and a direction identifier that identifies a direction to be traversed by the packet through the ring communication network. In some embodiments, the direction indicated by the direction identifier can be clockwise or counter-clockwise relative to a starting node from which the packet is to travel.

Abstract: Methods and apparatuses for enabling sub-seconds link failure detection in a multi-chassis link aggregation group (MC-LAG) system are described. A first network device of a packet network transmits an IP packet over a first link that is part of the MC-LAG, where the MC-LAG couples the first network device with a second network device and a third network device and the second and third network devices are part of an Inter-Chassis Redundancy (ICR) system. The IP packet includes a payload including a Bidirectional Forwarding Detection (BFD) control packet, where the destination address of the IP packet is one of a multicast IP address and a broadcast IP address.

Abstract: A first network node generates a message to be transmitted to a second network node. The message can include a value that identifies a type of the operational session, an identifier of the first network node that can control transmission of packets used during the operational session, and a length of the identifier. Further, the first and second network nodes can operate in an operational session in which the second network node can detect a failure.

Abstract: A method of exposing a maximum segment identifier depth (MSD) value of the network device is described. The method comprises transmitting to a centralized controller an attribute Type Length Value (TLV). A type of the attribute TLV includes a type of a maximum segment identifier depth (MSD) indicating that the MSD is a link MSD, a length of the attribute TLV includes a length of the MSD, and a value of the attribute TLV includes the MSD, which is a maximum number of segment routing (SR) labels supported at a link of the network node. The centralized controller is to use the attribute TLV to compute an SR tunnel with one or more SR labels, a label stack depth of the SR tunnel does not exceed the MSD, and the SR labels are used for steering a packet through an SR network.

Abstract: A method implemented by a network device acting as a border gateway protocol (BGP) speaker, of exposing a maximum segment identifier depth (MSD) value of the network device is described. The method comprises encoding the MSD value into a BGP Link State (BGP-LS) extension message. The BGP-LS extension message includes a type, a length and a MSD value. The type indicates the type of the MSD value, the length indicates the length of the MSD value and the MSD value indicates a lowest MSD value supported by the network device for enabling segment routing. The method continues with transmitting the BGP-LS extension message including the type, the length, and the MSD value to a network controller, where the network controller is to use the MSD value to compute a segment routing path including the network device.

Abstract: A method of operation of a Multiprotocol Label Switching network involves, in an active node of the network, receiving a first data packet from a source node and forwarding the first data packet to a destination node. At the same time, the active node measures a residence time of the first data packet in the active node. The active node then sends a further data packet containing residence time information.

Abstract: Understanding the performance of a Service Function Chain (SFC) and how Virtual Network Functions (VNFs) contribute to the performance of the SFC can assist in the maintenance of services and quality of experience the VNFs are expected to provide. In an exemplary embodiment, a residence time of packets traversing a service function or virtual network function is measured. The residence time characterizes the processing delay a service function introduces into a network.