Abstract: Some embodiments provide a forwarding element that inspects the size of each of several packets in a data flow to determine whether the data flow is an elephant flow. The forwarding element inspects the size because, in order for the packet to be of a certain size, the data flow had to already have gone through a slow start in which smaller packets are transferred and by definition be an elephant flow. When the forwarding element receives a packet in a data flow, the forwarding element identifies the size of the packet. The forwarding element then determines if the size of the packet is greater than a threshold size. If the size is greater, the forwarding element specifies that the packet's data flow is an elephant flow.

Abstract: Some embodiments provide a set of one or more network controllers that communicates with a wide range of devices, ranging from switches to appliances such as firewalls, load balancers, etc. The set of network controllers communicates with such devices to connect them to its managed virtual networks. The set of network controllers can define each virtual network through software switches and/or software appliances. To extend the control beyond software network elements, some embodiments implement a database server on each dedicated hardware. The set of network controllers accesses the database server to send management data. The hardware then translates the management data to connect to a managed virtual network.

Abstract: A method of manages a set of managed forwarding elements that forward data between machines. The method configures (1) a first managed forwarding element to operate in a first network that uses first and second address spaces that at least partially overlap with each other, (2) a second managed forwarding element to operate in a second network that uses the first address space, and (3) a third managed forwarding element to operate in a third network that uses the second address space. A machine in the second network and a machine in the third network have an identical address that belongs to both the first and second address spaces. The method directs the first managed forwarding element to connect to the second and third managed forwarding elements in a manner that enables the first managed forwarding element to forward data from a machine in the first network to the machine in the second network via the second managed forwarding element.

Abstract: A method of manages a set of managed forwarding elements that forward data between machines. The method configures (1) a first managed forwarding element to operate in a first network that uses first and second address spaces that at least partially overlap with each other, (2) a second managed forwarding element to operate in a second network that uses the first address space, and (3) a third managed forwarding element to operate in a third network that uses the second address space. A machine in the second network and a machine in the third network have an identical address that belongs to both the first and second address spaces. The method directs the first managed forwarding element to connect to the second and third managed forwarding elements in a manner that enables the first managed forwarding element to forward data from a machine in the first network to the machine in the second network via the second managed forwarding element.

Abstract: Some embodiments provide a forwarding element that detects and handles elephant flows. In detecting, the forwarding element of some embodiments monitors statistics or measurements relating to a data flow. In handling, the forwarding element marks each packet associated with a detected elephant flow in some manner to differentiate it from a packet associated with a mouse flow. Alternatively, the forwarding element of break elephant flows into a number mouse flow by facilitating in sending packets associated with the detected elephant flow along different paths.

Abstract: Some embodiments provide a system that detects whether a flow is an elephant flow; and if so, the system treats it differently than a mouse flow. The system of some embodiment detect elephants based on one or more of the following: statistics associated with a flow, packet segment size, and invoked system calls. Also, some embodiments use one or more various methods to handle elephant flows. Examples of such methods include marking each packet belonging to an elephant with a particular marking, breaking the elephants into mice, reporting the elephant to a network controller, and selectively choosing a route for each packet belonging to the elephant.

Abstract: Some embodiments provide a forwarding element that inspects the size of each of several packets in a data flow to determine whether the data flow is an elephant flow. The forwarding element inspects the size because, in order for the packet to be of a certain size, the data flow had to already have gone through a slow start in which smaller packets are transferred and by definition be an elephant flow. When the forwarding element receives a packet in a data flow, the forwarding element identifies the size of the packet. The forwarding element then determines if the size of the packet is greater than a threshold size. If the size is greater, the forwarding element specifies that the packet's data flow is an elephant flow.

Abstract: Some embodiments provide a set of one or more network controllers that communicates with a wide range of devices, ranging from switches to appliances such as firewalls, load balancers, etc. The set of network controllers communicates with such devices to connect them to its managed virtual networks. The set of network controllers can define each virtual network through software switches and/or software appliances. To extend the control beyond software network elements, some embodiments implement a database server on each dedicated hardware. The set of network controllers accesses the database server to send management data. The hardware then translates the management data to connect to a managed virtual network.

Abstract: Some embodiments provide a set of one or more network controllers that communicates with a wide range of devices, ranging from switches to appliances such as firewalls, load balancers, etc. The set of network controllers communicates with such devices to connect them to its managed virtual networks. The set of network controllers can define each virtual network through software switches and/or software appliances. To extend the control beyond software network elements, some embodiments implement a database server on each dedicated hardware. The set of network controllers accesses the database server to send management data. The hardware then translates the management data to connect to a managed virtual network.

Abstract: Some embodiments provide a set of one or more network controllers that communicates with a wide range of devices, ranging from switches to appliances such as firewalls, load balancers, etc. The set of network controllers communicates with such devices to connect them to its managed virtual networks. The set of network controllers can define each virtual network through software switches and/or software appliances. To extend the control beyond software network elements, some embodiments implement a database server on each dedicated hardware. The set of network controllers accesses the database server to send management data. The hardware then translates the management data to connect to a managed virtual network.

Abstract: Some embodiments provide a method for a first network controller located at a first domain that manages a logical network spanning several physical domains including the first domain. Upon reconnection to a second network controller located at a second physical domain of the several physical domains after a period of disconnect, the method receives a first set of updates indicating modifications to logical network state from the second network controller. The method reconciles any conflicts between (i) the logical network state stored at the first controller, (ii) the first set of updates received from the second network controller, and (iii) updates received from other network controllers located at different physical domains of the several physical domains. The method transmits a second set of updates to the second controller indicating modifications to the logical network state based on the reconciliation of conflicts.

Abstract: Some embodiments provide a method for a first network controller located at a first physical domain that manages a logical network spanning several physical domains including the first domain. The method detects that connectivity is lost between the first network controller and a second network controller located in a second one of the physical domains. The method identifies a set of forwarding elements managed by the first network controller that implement the logical network. The method instructs the set of forwarding elements to drop packets for the logical network received from forwarding elements in the second physical domain.

Abstract: Some embodiments provide a network controller for managing a logical network that spans several physical domains. The network controller is located at a particular one of the several physical domains. The network controller includes a first storage for storing network state information that is local to the particular physical domain. The network controller includes a second storage for storing a first type of global network state information for the logical network. The network controller includes a third storage for storing a second type of global network state information for the logical network. The network controller includes an interface for communicating with other network controllers located at the other physical domains in the several physical domains spanned by the logical network. The interface is for sharing the first and second types of global network state information.

Abstract: Some embodiments provide a method for a first network controller located at a first physical domain that manages a logical network spanning several physical domains including the first domain. The method stores a set of context identifiers for assignment to logical entities. The context identifiers are for use in packets sent between managed forwarding elements in order to store logical network information in the packets. While connected to a master controller for the logical network at a second physical domain of the several physical domains, the method forwards state input requiring assignment of context identifiers to the master controller. While connectivity is lost with the master controller, the method assigns context identifiers from the stored set of context identifiers to logical entities.

Abstract: In one embodiment, a reservation proxy monitors for received connectivity check messages or beginning-of-media-flow indication messages. When either type of message is observed, the reservation proxy requests resource allocation for a media flow associated with the received message. The amount of resource allocation requested may be coordinated by exchanging messages with a call controller or policy server for one of the endpoints of the media flow, or the amount of resource allocation may be identified within the received message.

Abstract: A method of manages a set of managed forwarding elements that forward data between machines. The method configures (1) a first managed forwarding element to operate in a first network that uses first and second address spaces that at least partially overlap with each other, (2) a second managed forwarding element to operate in a second network that uses the first address space, and (3) a third managed forwarding element to operate in a third network that uses the second address space. A machine in the second network and a machine in the third network have an identical address that belongs to both the first and second address spaces. The method directs the first managed forwarding element to connect to the second and third managed forwarding elements in a manner that enables the first managed forwarding element to forward data from a machine in the first network to the machine in the second network via the second managed forwarding element.

Abstract: In one embodiment, a reservation proxy monitors for received connectivity check messages or beginning-of-media-flow indication messages. When either type of message is observed, the reservation proxy requests resource allocation for a media flow associated with the received message. The amount of resource allocation requested may be coordinated by exchanging messages with a call controller or policy server for one of the endpoints of the media flow, or the amount of resource allocation may be identified within the received message.

Abstract: A node in an overlay network requests a ranked list of other nodes in the overlay network that can provide a desired piece of content or service to the requesting node. A separate node such as a router generates the ranked list using a routing algorithm, returning the list to the requesting node so that the requesting node may acquire the desired content or service from the nearest node in the overlay network.

Abstract: In one embodiment, a reservation proxy monitors for received connectivity check messages or beginning-of-media-flow indication messages. When either type of message is observed, the reservation proxy requests resource allocation for a media flow associated with the received message. The amount of resource allocation requested may be coordinated by exchanging messages with a call controller or policy server for one of the endpoints of the media flow, or the amount of resource allocation may be identified within the received message.

Abstract: In one embodiment, a reservation proxy monitors for received connectivity check messages or beginning-of-media-flow indication messages. When either type of message is observed, the reservation proxy requests resource allocation for a media flow associated with the received message. The amount of resource allocation requested may be coordinated by exchanging messages with a call controller or policy server for one of the endpoints of the media flow, or the amount of resource allocation may be identified within the received message.