Google Inc.

Leon Poutievski

Amin Vahdat

Ashish Naik

Shashidhar R Gandham

Amit Gupta

Subhasree Mandal

Joon Suan Ong

Subbaiah Venkata

Hong Liu

Cedric Fung Lam

Ryohei Urata

Rajiv Ramanathan

Xiaoxue Zhao

James Wanderer

Min Zhu

Barry Friedman

James M Wanderer

Subhasree Madal

A system and method are provided for updating a network including at least one optical circuit switch (OCS) to transition from an existing network topology to a new network topology. One or more intermediate topologies between the existing topology and the new topology are created. Creating the intermediate topologies includes selecting first links to be added to the existing topology without removing links, selecting additional links to be added to the existing topology upon removal of one or more existing links, and adding one or more of the selected first and additional links to the existing topology to create a first intermediate topology. It is determined whether any of the selected first and additional links are still to be added, and if no selected first and additional links are to be added, remaining links are removed. The transition from the existing topology to the first intermediate topology is then effected.

System and method for adjusting network topology without packet loss

As an overview, the present disclosure presents a system for increasing network optimization. In particular, the disclosure discusses a unified system for control of data routing in a dynamic network. In some implementations, edge devices (i.e., hosts or exterior switches) are interconnected through a network fabric (i.e., a plurality of interior switches). The hosts and switches include forwarding engines, which determine the next destination of incoming traffic. The disclosure discusses a network controller that collects application requirements and programs the forwarding engines of the edge devices and the network fabric responsive to the application requirements.

Using unified API to program both servers and fabric for forwarding for fine-grained network optimizations

Aspects of the disclosure relate generally to switches responding to master controllers before establishing a secure connection in an in-band controlled network. In order to do so, a computing device may receive a request packet from a transmitting device, the request packet originating from a controller computer. When the request packet enters a designated port on the computing device, the computing device may identify routing data from the received request packet, the routing data indicating a path to respond to the controller computer. The computing device may next populate a table using the identified routing data of the request packet. The computing device may send a response packet to the controller computer using the identified routing data in the populated table. From here, a connection may be established between the computing device and controller computer.

In-band centralized control with connection-oriented control protocols

Network performance may be improved by adjusting a logical network topology while avoiding attendant disruptions. By identifying an alternative logical topology, routing network traffic away from links that will be eliminated from the alternative logical topology, and updating a traffic routing plan upon the adoption of the alternative logical topology, a network may adopt a more efficient topology without misdirecting network traffic.

Networking systems with dynamically changing topologies

A network topology system for reducing the hardware links in a centrally-controlled network having a plurality of network switches and a plurality of centralized controllers controlling those switches. The global network of switches and controllers is broken up into domains, wherein a domain contains a subset of controllers and switches, and a switch in a domain is controlled by one or more controllers. In-band hardware links, which carry both data and control information, are used to connect the controllers and switches in a domain, and thereby reduce the number of hardware links from that used in networks which have separate hardware links for both data and control information.

Systems and methods for reducing network hardware of a centrally-controlled network using in-band network connections

Aspects of the disclosure relate generally to selecting and identifying a primary controller server among a group of servers on a network. In order to do so, a first computer may set a first number to zero when a storage system associated with the first computer is initialized. The first computer may conduct an election protocol to select a primary controller computer from a plurality of computers. After selecting the primary computer, increase the first number by a given value and send it to the selected primary computer. The selected primary computer may set a second number corresponding to an absolute time when the storage system associated with the first computer is initialized. The selected primary computer may receive the first number from the first computer. The selected primary computer may send the numbers to a client device. After sending, the primary computer may establish a connection with the client.

System and method for determining a primary controller in software defined networking

A patch panel device has communication ports respectively associated with a unique binary number having a number of binary digits, and a plurality of computing devices are each respectively coupled to at least one of the ports. A connectivity test includes configuring the patch panel device to send a message to a first sending device in response to receiving data at a port associated with a binary number having a first value as the respective binary digit, and not to send a message to a second sending device in response to receiving data at a port associated with a binary number having a second value as the respective binary digit. Each of the computing devices is caused to transmit data for arrival at a corresponding port, an indication is received for each device regarding whether the device received a message. A connectivity map is generated.

Determining physical connectivity of data center devices

A network topology system for combining in-band hardware links for network redundancy with out-of-band hardware links for facile initialization in a network with centralized control architecture, wherein the combined use of in-band and out-of-band hardware links further reduces the overall hardware links required for centralized control. An initialization processor allows direct out-of-band hardware links between a plurality of centralized controllers to be used for initialization, while further allowing in-band hardware links for connections between two switches, and between a switch and a controller, wherein the use of in-band hardware links allows the same hardware links to convey both data and control communications, increasing redundancy, and reducing the number of hardware links required by the network domain as a whole.

Systems and methods for improving network redundancy and for facile initialization in a centrally-controlled network

A system, apparatus, and method for link layer address resolution of overlapping network addresses is disclosed. In one aspect, the method performed on a first device includes receiving a first address resolution request from a second device, the first address resolution request having a sender network address and a target network address, wherein the target network address is an overlapping network address that is a gateway address of the second device and a network address of a third device, creating a first address resolution response having a sender link layer address associated with the first device, and sending the first address resolution response to the second device.

Link layer address resolution of overlapping network addresses

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for semi-centralized routing. In one aspect, a computer-implemented method receives a network protocol packet at a router adapted for routing data packets to one or more additional routers. The network protocol packet conforms to a routing protocol that provides distributed routing computation. The method also sends the network protocol packet, through a controller, to a selected one of a plurality of route control servers. The method also processes the network control packet at the selected route control server to generate a routing computation result that conforms to the routing protocol. The method also generates routing information based on the routing computation. The routing information conforms to a control protocol that provides centralized routing computation. The method also sends the routing information to the router for routing of data packets based on the control protocol.

Semi-centralized routing

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for semi-centralized routing. One of the methods includes receiving one or more routes and determining that a received route identifies a new set of paths different from each routing path group in a maintained set of routing path groups. A new routing path group is created that corresponds to the new set of paths. The new routing path group is assigned an identifier of the routing path group. The new routing path group is converted to a corresponding new flow path group. A flow path group that was converted from the routing path group is replaced on a network device with the converted new flow path group.

Semi-centralized multiple path routing

Systems and methods for optimizing port usage in an optical circuit switch are disclosed herein. A plurality of optical circulators can be coupled to the plurality of input and output ports of an optical circuit switch. An optical circulator coupled to an input port and an optical circulator coupled to an output port can form a bidirectional pair capable of communicating with any other bidirectional pair of the optical circuit switch. In this regard, the number of bidirectional ports of an optical circuit switch can be increased allowing additional bandwidth to flow through the optical circuit switch. Increasing the efficiency and capabilities of optical circuit switches within a large scale communications network can offer increased functionality and performance with little trade off.

Optical circuit switch optimization using optical circulators

A system and method of detecting polarity inversion in an optical switching circuit is disclosed. The method includes performing a first round of a port verification process on at least two optical ports, transmitting a payload from at least one optical port in the at least two optical ports, determining if the payload was received at a second optical port in the at least two optical ports, assigning a pair of ports to a first group in the case that the predetermined payload was communicated between the pair of ports, and assigning a pair of ports to a second group in the case that the predetermined payload was not communicated between the pair of ports. The method also includes determining that either the first group of ports or the second group of ports has inverted polarity.

Growing community of inventors

Santa Clara, CA, United States of America

Leon Poutievski