# US 10,455,436 B2 · SDN-based channel estimation for multiplexing between LOS mmWaves, NLOS sub-6 GHz and FSO > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,455,436 B2 - Document ID: US10455436B2 - Status: Granted - Kind: B2 - Application number: 16/188,491 - Filed: 2018-11-13 - Published: 2019-03-28 - Granted: 2019-10-22 - Earliest claimed: 2016-08-30 - Assignees: Nxgen Partners IP, LLC - Applicants: NxGen Partners IP, LLC - Inventors: Solyman Ashrafi - Web page: https://patentgrep.com/patent/US10455436B2 ## CPC - H04B 10/1129: {Arrangements for outdoor wireless networking of information} - H04B 10/038: using bypasses - H04B 10/1123: {Bidirectional transmission} - H04L 41/0823: characterised by the purposes of a change of settings, e.g. optimising configuration for enhancing reliability (for optimising operational conditions of wireless networks H04W24/02) - H04L 41/0894: Policy-based network configuration management - H04L 41/0895: Configuration of virtualised networks or elements, e.g. virtualised network function or OpenFlow elements - H04L 41/20: {Network management software packages} - H04L 41/40: using virtualisation of network functions or resources, e.g. SDN or NFV entities - H04L 41/5054: Automatic deployment of services triggered by the service manager, e.g. service implementation by automatic configuration of network components - H04W 24/04: Arrangements for maintaining operational condition - H04W 24/08: Testing, {supervising or monitoring} using real traffic - H04W 72/54: based on quality criteria - H04W 76/15: Setup of multiple wireless link connections - H04W 84/00: Network topologies - H04L 41/12: Discovery or management of network topologies - H04L 41/5087: {wherein the managed service relates to voice services (management of VoIP services H04M7/0081)} - H04L 43/0852: Delays - H04W 24/02: Arrangements for optimising operational condition - H04W 28/16: Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service] - H04W 52/0203: {in the radio access network or backbone network of wireless communication networks} - H04W 84/045: {using private Base Stations, e.g. femto Base Stations, home Node B} - H04W 92/12: between access points and access point controllers - Y02D 30/70: in wireless communication networks - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract A system for providing small cell backhaul communication comprises a small cell backhaul network includes a plurality of small cell network nodes. At least one transceiver at each of the plurality of small cell network nodes establishes communication links with other small cell network nodes within the small cell backhaul network. A fast failover group table is located at each of the plurality of small cell network nodes. A software defined network controller controls communication link configuration by the at least one transceiver. The software defined network controller calculates for each of the communications links within the small cell backhaul network a primary link and at least one back-up link. The software defined network controller stores the calculated primary link and at least one back-up link in the fast failover group table of each of the plurality of small cell network nodes. Each of the plurality of small cell network nodes locally determining to establish the at least one back-up link responsive to a determination that the primary link is down and the stored at least one back-up link for an associated small cell network node. ## Claims ### Claim 1 A system for providing small cell backhaul communication, comprising: a small cell backhaul network including a plurality of small cell network nodes; at least one transceiver at each of the plurality of small cell network nodes for establishing communication links with other small cell network nodes within the small cell backhaul network; a fast failover group table located at each of the plurality of small cell network nodes; a software defined network (SDN) controller for controlling communication link configuration by the at least one transceiver between the other small cell network nodes of the small cell backhaul network, the software defined network controller calculating for each of the communications links within the small cell backhaul network a primary link and at least one back-up link, the software defined network controller storing the calculated primary link and at least one back-up link in the fast failover group table of each of the plurality of small cell network nodes; and wherein each of the plurality of small cell network nodes locally determines to establish the at least one back-up link responsive to a determination that the primary link is down and the stored at least one back-up link for an associated small cell network node. ### Claim 2 (depends on 1) The system of claim 1, wherein each of the plurality of small cell network nodes locally determines to establish the at least one back-up link in a data plan of the small cell network. ### Claim 3 (depends on 1) The system of claim 1, wherein the SDN controller uses an SDN control plane to calculate the primary link and the at least one back-up link. ### Claim 4 (depends on 1) The system of claim 1, wherein each of the plurality of small cells of the small cell network nodes use rapid link monitoring to detect if the primary link from a small cell backhaul node has failed, if a failed primary link is detected the small cell backhaul node switches to the at least one backup link stored in the fast failover group table. ### Claim 5 (depends on 1) The system of claim 1, wherein each of the plurality of small cell network nodes of the small cell backhaul network uses Bidirectional Forwarding Detection to determine if the primary link has failed. ### Claim 6 (depends on 1) The system of claim 1, wherein each of the plurality of small cell network nodes of the small cell backhaul network periodically transmits a Bidirectional Forwarding Detection message to each neighboring small cell network node to detect communications link status. ### Claim 7 (depends on 6) The system of claim 6, wherein each of the plurality of small cell network nodes of the small cell backhaul network periodically transmits a MAC layer protocol message to each neighboring small cell node to detect communications link status. ### Claim 8 (depends on 6) The system of claim 6, wherein the plurality of small cell network nodes of the small cell backhaul network uses crankback forwarding to establish a path to a destination when each of the primary link and backup link for a small cell network node are not working. ### Claim 9 (depends on 1) The system of claim 1, wherein the SDN controller associates at each small cell network node of the plurality of small cell network nodes a dedicated OpenFlow port for each neighboring small cell network node in the fast failover group table. ### Claim 10 (depends on 1) The system of claim 1, wherein the SDN controller associates a first OpenFlow port with the primary link and at least one second OpenFlow port with the at least one back-up link. ### Claim 11 A method for providing small cell backhaul communication to a small cell backhaul network including a plurality of small cell network nodes comprising: establishing communication links with other small cell network nodes within the small cell backhaul network using at least one transceiver at each of the plurality of small cell network nodes; controlling communication link configuration by the at least one transceiver between the other small cell network nodes of the small cell backhaul network using a software defined network (SDN) controller, wherein the process of controlling the communications link configuration further comprises: calculating for each of the communications links within the small cell backhaul network a primary link and at least one back-up link using the software defined network controller; storing the calculated primary link and the at least one back-up link in a fast failover group table at each of the plurality of small cell network nodes; and determining locally at each of the plurality of small cell network nodes to establish the at least one back-up link responsive to a determination that the primary link is down and the stored at least one back-up link for an associated small cell network node. ### Claim 12 (depends on 11) The method of claim 11, wherein the step of determining locally further comprises locally determining to establish the at least one back-up link in a data plan of the small cell network at each of the plurality of small cell network nodes. ### Claim 13 (depends on 11) The method of claim 11, wherein the step of calculating further comprises calculating the primary link and the at least one backup link using an SDN control plane. ### Claim 14 (depends on 11) The method of claim 11, further comprising: detecting if the primary link from a small cell backhaul node has failed using rapid link monitoring by each of the plurality of small cell network nodes of the small cell backhaul network; and switching to the at least one back-up link stored in the fast failover group table if the failed primary communications link is detected. ### Claim 15 (depends on 11) The method of claim 11, wherein each of the plurality of small cell network nodes of the small cell backhaul network uses Bidirectional Forwarding Detection to determine if the primary link has failed. ### Claim 16 (depends on 15) The method of claim 15, transmitting periodically a Bidirectional Forwarding Detection message to each neighboring small cell network node to detect communications link status from each of the plurality of small cell network nodes of the small cell backhaul network. ### Claim 17 (depends on 15) The method of claim 15, transmitting periodically a MAC layer protocol message to each neighboring small cell node to detect communications link status from each of the plurality of small cell network nodes of the small cell backhaul network. ### Claim 18 (depends on 15) The method of claim 15, establishing a path to a destination when each of the primary link and the at least one back-up link for a small cell network node is not working using crankback forwarding at the plurality of small cell network nodes of the small cell backhaul network. ### Claim 19 (depends on 11) The method of claim 11 associating, by the SDN controller, at each small cell network node of the plurality of small cell network nodes a dedicated OpenFlow port for each neighboring small cell network node in the fast failover group table. ### Claim 20 (depends on 11) The method of claim 11, associating, by the SDN controller, a first OpenFlow port with the primary link and at least one second OpenFlow port with the at least one back-up link.