128 Technology, Inc.

Juniper Networks, Inc.

Cisco Technology, Inc.

Abilash Menon

Robert F Penfield

Patrick John MeLampy

Michael Baj

Hadriel S Kaplan

Anna Yungelson

Patrick Timmons

Scott A McCulley

Jacob Dionne

Prashant Kumar

Markus Jork

John M Peterson

Sarah V Jaffer

Kaushik Adesh Agrawal

Michael John Adams

Ryan Koss

Tong Jiang

Thomas E Sullivan

Subrat Mohanty

Ganesh Srinivasa Bhat

James Cameron Gibson

Chaohui Zhang

Hendrik Scholz

Eden Tan

Manpreet Sing Sandhu

Pranav Kethe-Sai

Avinash Prakash Bhat

Scott Peter Inguagiato

Francisco Jose Mendez Cirera

Scott A Mcculley

Techniques are described for forming on-demand mesh connections between spoke routers of a Software-Defined Wide Area Network (SD-WAN) arranged in a hub-and-spoke topology. A first spoke router modifies the first packet to include metadata specifying first reachability information and first Internet Protocol (IP) address information for the first spoke router. The first spoke router forwards the first packet to a hub router for forwarding to a second spoke router. The first spoke router receives a second packet from the hub router that includes metadata specifying second reachability information and second IP address information for the second spoke router. In response to determining that the first reachability information is compatible with the second reachability information, the first spoke router initiates a peering connection with the second spoke router along a path which bypasses the hub router for forwarding subsequent packets of the forward packet flow.

Opportunistic mesh for software-defined wide area network (SD-WAN)

In exemplary embodiments of the present invention, a router determines whether or not to establish a stateful routing session based on the suitability of one or more candidate return path interfaces. This determination is typically made at the time a first packet for a new session arrives at the router on a given ingress interface. In some cases, the router may be configured to require that the ingress interface be used for the return path of the session, in which case the router may evaluate whether the ingress interface is suitable for the return path and may drop the session if the ingress interface is deemed by the router to be unsuitable for the return path. In other cases, the router may be configured to not require that the ingress interface be used for the return path, in which case the router may evaluate whether at least one interface is suitable for the return path and drop the session if no interface is deemed by the router to be suitable for the return path.

Reverse forwarding information base enforcement

Techniques are disclosed for session-based load-balancing of network traffic to network service instances. In one example, a network device receives a first packet of a forward packet flow from a network service instance of a plurality of network service instances after application of a network service. The first packet specifies a Media Access Control (MAC) address of the network service instance as a source MAC address. The network device defines a session comprising the forward packet flow and a reverse packet flow and stores an association between the session and the MAC address of the network service instance. The network device determines that a second packet received from a destination device is associated with the reverse packet flow of the session. The network device forwards the second packet to the same network service instance based on the association between the session and the MAC address of the network service instance.

Service function chaining with session-based routing

A router advertises an aggregated service or route that can be evaluated by other routers as a unitary segment rather than as a group of individual links/paths associated with the aggregated service or route. The aggregated service or route can be based on service and topology state information received from one or more other routers and can be advertised with the router as the nexthop for the aggregated service or route. The router can advertise an aggregated metric for the aggregated service or route for use in such evaluation. An aggregated route can be associated with different aggregated metrics for different services.

Routing using segment-based metrics

A first router generates session establishment metrics for use in network path selection. For example, a plurality of routers connect a client device to a network service instance hosted by a server. A first router is connected to the network service instance via first and second paths. The first router receives session performance requirements for a session between the client device and the network service instance. The first router forwards, along the first path, network traffic for the session by modifying a first packet of the session to include a session identifier for the session. The first router determines that session establishment metrics for the session do not satisfy the session performance requirements. In response, the first router forwards, along the second path, the network traffic for the session by modifying a second packet of the session to include the session identifier for the session.

Session monitoring using metrics of session establishment

Techniques are described for a router providing metric-based multi-hop path selection. For example, a first router of a plurality of routers receives a plurality of network performance metrics for a plurality of links interconnecting the plurality of routers. The plurality of links form a plurality of multi-hop paths through the plurality of routers to a service instance. The router determines, based on the plurality of network performance metrics for the plurality of links, an end-to-end performance of each of the plurality of multi-hop paths. The router selects a multi-hop path over which to forward traffic associated with the session based on the end-to-end performance of each of the plurality of multi-hop paths and one or more performance requirements for a service associated between a session between a client device and the service instance. The router forwards the traffic to the service instance along the selected multi-hop path.

Metric-based multi-hop path selection

One function of a communications network, or of nodes in such a network, is to gather data that is useful in assessing network performance, and quantifying metrics of node and/or network performance. Various embodiments disclosed herein improve the ability of nodes and networks to gather such data, and quantify metrics of node and/or network performance by selectively marking existing network traffic, and in preferred embodiments without having to dilute network traffic by generating and transmitting dummy data packets.

In-line performance monitoring

A routing system for implementing a service and topology exchange protocol (STEP) includes a primary STEP server configured to maintain a STEP repository and a plurality of routers, with each router including a STEP client in communication with the primary STEP server. The STEP client of each router is configured to transmit, using STEP, STEP documents containing service and topology state information for at least one route or service available through the router to the primary STEP server for storage in the STEP repository. The primary STEP server is configured to transmit to the STEP client of each router, using STEP, service and topology state information from the STEP repository for at least one other router based on configured relationships between routers. Each router is configured to make routing decisions based at least in part on the service and topology state information from the at least one other router.

Service and topology exchange protocol

Techniques are disclosed for session-based routing of multipoint Open Systems Interconnection (OSI) Model Layer-2 (L2) frames of an L2 network extended over Layer-3 (L3) networks. In one example, L2 networks connect a source device to an ingress router and receiver devices to egress routers. An L3 network connects the ingress and egress routers. The ingress router receives, from the source device, a multipoint L2 frame destined for the receiver devices. The ingress router forms, for each egress router that is connected to at least one multipoint receiver device, a unicast L3 packet for the L2 frame and forwards the unicast L3 packet to the egress router. Each egress router generates, in response to receiving the unicast L3 packet, the multipoint L2 frame and forwards, to the receiver devices, the multipoint L2 frame.

Point-to-multipoint Layer-2 network extension over Layer-3 network

Point-to-multipoint layer-2 network extension over layer-3 network

Routing packets by a router involves establishing a first flow configured for forwarding the packets from a first ingress interface to a first egress interface of the router; determining a condition to modify the first flow; deactivating the first flow; establishing a second flow configured for forwarding the packets from at least one of (1) the first ingress interface to a second egress interface, (2) a second ingress interface to the first egress interface, or (3) a second ingress interface to a second egress interface; and activating the second flow.

Flow modification including shared context

Techniques are disclosed for inline security key exchanges between network devices. An example network device includes one or more processors and memory coupled to the one or more processors. The memory stores instructions that, upon execution, cause one or more processors to obtain a first payload key and obtain a path key. The instructions cause the one or more processors to encrypt a first payload of a first packet using the first payload key and insert the first payload key into first metadata of the first packet. The instructions cause the one or more processors to encrypt the first metadata using the path key and send the first packet to another network device.

Inline security key exchange

Techniques are disclosed for promulgating service information and topology information in a network in a high availability manner. An example device is configured to create a first service and topology exchange protocol (STEP) document. The first STEP document includes service information and topology information. The example device is configured to send the first STEP document to a first STEP repository for forwarding to at least one subscribing network device. The example device is also configured to send the first STEP document to a second STEP repository for forwarding to the at least one subscribing network device.

Service and topology exchange protocol having client-driven active-active repositories with high availability

Techniques are disclosed for session-based routing within Open Systems Interconnection (OSI) Model Layer-2 (L2) networks extended over Layer-3 (L3) networks. In one example, L2 networks connect a first client device to a first router and a second client device to a second router. An L3 network connects the first and second routers. The first router receives, from the first client device, an L2 frame destined for the second client device. The first router generates an L3 packet comprising an L3 header specifying L3 addresses of the first and second routers, a first portion of metadata comprising L2 addresses for the first and second client devices, and a second portion of metadata comprising L3 addresses for the first and second client devices, and forwards the L3 packet to the second router. The second router recovers the L2 frame from the metadata and forwards the L2 frame to the second client device.

Growing community of inventors

Boxborough, MA, United States of America

Abilash Menon