Abstract: A controller may control switches such as physical and software switches in a network. The controller may generate virtual switches from groups of end hosts in forming a virtual network topology. The controller may receive one or more network policy rules that govern network traffic through the switches. For a given network policy rule, the controller may perform a test in determining whether the network satisfies the network policy rule. The test may be performed based on a testing rule identifying test parameters and expected test results. The controller may perform tests in determining whether the network satisfies the testing rule and the corresponding network policy rule. The tests may be performed via simulation at the controller or by injecting a tagged test packet into the network.

Abstract: A network may include network switches with network switch ports that may be coupled to end hosts. The network switches may be controlled by a controller such as a controller server. Virtual switches may be formed using the controller from groups of the network switch ports and the end hosts. Each virtual switch may include virtual interfaces associated with end hosts or network switches. Virtual links may be formed that define network connections between the virtual interfaces and end hosts or between two virtual interfaces. Virtual network policies such as selective packet forwarding, packet dropping, packet redirection, packet modification, or packet logging may be implemented at selected virtual interfaces to control traffic through the communications network. The controller may translate the virtual network policies into network switch forwarding paths that satisfy the virtual network policies.

Abstract: A controller may control switches such as physical and software switches in a network. The controller may generate virtual switches from groups of end hosts in forming a virtual network topology. The controller may receive one or more network policy rules that govern network traffic through the switches. For a given network policy rule, the controller may perform a test in determining whether the network satisfies the network policy rule. The test may be performed based on a testing rule identifying test parameters and expected test results. The controller may perform tests in determining whether the network satisfies the testing rule and the corresponding network policy rule. The tests may be performed via simulation at the controller or by injecting a tagged test packet into the network.

Abstract: A network controlled by a controller may include end hosts that are coupled to the switches. The network may be coupled to gateways that interface between the network and an external network. The network may include subnetworks formed from respective portions of the end hosts of the network. The controller may create virtual gateways that interface between each of the subnetworks and the network by providing the end hosts of each subnetwork with virtual gateway Ethernet addresses. The controller may receive a network packet having a virtual gateway Ethernet address from an end host of a given subnetwork. The network packet may be destined for an end host of an external network or subnetwork. The controller may forward the network packet to the destination end host by redirecting the network packet through a selected gateway or by controlling the switches to perform gateway functions.

Abstract: A network controlled by a controller may include end hosts that are coupled to the switches. The network may be coupled to gateways that interface between the network and an external network. The network may include subnetworks formed from respective portions of the end hosts of the network. The controller may create virtual gateways that interface between each of the subnetworks and the network by providing the end hosts of each subnetwork with virtual gateway Ethernet addresses. The controller may receive a network packet having a virtual gateway Ethernet address from an end host of a given subnetwork. The network packet may be destined for an end host of an external network or subnetwork. The controller may forward the network packet to the destination end host by redirecting the network packet through a selected gateway or by controlling the switches to perform gateway functions.

Abstract: Network switches that are controlled by a controller server may contain ports through which network packets are received and forwarded. An architect may configure the controller server to create virtual switches. Each virtual switch may be formed from a subset of the ports of the network switches. The architect may assign administrators to the virtual switches. The administrators may configure the virtual switches. An administrator may use a command line interface to configure a virtual switch. The administrator may use commands such as a show port command, an access list command, a show access list command, and a membership rule command to manage the virtual switch. The controller server may prevent the administrator from logging on to virtual switches that have been assigned to other administrators.

Abstract: A network may include network switches with network switch ports that may be coupled to end hosts. The network switches may be controlled by a controller such as a controller server. Virtual switches may be formed using the controller from groups of the network switch ports and the end hosts. Each virtual switch may include virtual interfaces associated with end hosts or network switches. Virtual links may be formed that define network connections between the virtual interfaces and end hosts or between two virtual interfaces. Virtual network policies such as selective packet forwarding, packet dropping, packet redirection, packet modification, or packet logging may be implemented at selected virtual interfaces to control traffic through the communications network. The controller may translate the virtual network policies into network switch forwarding paths that satisfy the virtual network policies.

Abstract: Network switches that are controlled by a controller server may contain ports through which network packets are received and forwarded. An architect may configure the controller server to create virtual switches. Each virtual switch may be formed from a subset of the ports of the network switches. The architect may assign administrators to the virtual switches. The administrators may configure the virtual switches. An administrator may use a command line interface to configure a virtual switch. The administrator may use commands such as a show port command, an access list command, a show access list command, and a membership rule command to manage the virtual switch. The controller server may prevent the administrator from logging on to virtual switches that have been assigned to other administrators.