Abstract: In one embodiment, a system includes a station circuit. The station circuit includes a data layer and a transport layer. The station circuit is capable of a source mode and a destination mode. The data layer of the station circuit in source mode disassembles a source packet into one or more source parcels and sends the one or more source parcels to the transport layer. The station circuit in destination mode receives the one or more destination parcels over a ring at its transport layer, reassembles the one or more destination parcels into a destination packet, and delivers the destination packet from the transport layer to the data layer. The transport layer of the station circuit in source mode transmits the one or more source parcels over the ring. The transport layer of the station circuit in destination mode receives the one or more destination parcels over the ring.

Abstract: A Software Defined Network (SDN) includes a plurality of forwarding devices and a routing control device located separate from the forwarding devices. The routing control device, establishes paths to and from the network forwarding devices. Using such paths, forwarding devices send the routing control device information reflecting the topology if the network. Embodiments disclosed herein enable automatic discovery of the topology of the network and the paths to and from the routing control device.

Abstract: A method and Provider Edge Bridge for providing a C-tagged service interface or a port-based interface. In one embodiment, the Provider Edge Bridge includes a Customer Virtual Local Area Network (C-VLAN) component having a Customer Edge Port (CEP) and a plurality of Provider Edge Ports (PEPs). A first Service VLAN (S-VLAN) component is connected to the C-VLAN component and to a Metro Ethernet Network (MEN). A second S-VLAN component is connected to the C-VLAN component, to the first S-VLAN component, and to an External Network Network Interface (E-NNI). A plurality of ports on the first S-VLAN component facing the MEN are designated as S-VLAN Remote Customer Ports (RCPs) when the ports are connecting internal services in the MEN to provide the C-tagged service interface or the port-based interface to customers from a far side of the E-NNI.

Abstract: An apparatus for forwarding an Fiber Channel over Ethernet (FCoE) data frame into an Ethernet network comprising a processor configured to receive a data frame on a input port, obtain a first destination address and a virtual local area network identifier (VID), determine whether the first destination address and the VID matches an entry within a forwarding table, construct a key when the first destination address and VID matches the entry and the data frame is a FCoE frame, and forward the data frame as an outgoing data frame via an output port when the key matches a rule that permits forwarding the data frame.

Abstract: According to one embodiment, a server includes an accelerated network interface card (NIC), the accelerated NIC including a plurality of network ports including multiple Peripheral Component Interconnect express (PCIe) ports, an Overlay Network Offload System (ONOS), the ONOS including logic adapted for providing overlay functionality to network traffic received by the accelerated NIC, a first receiving/transmitting (RX/TX) packet buffer adapted for caching network traffic sent to or received from a network, a second RX/TX packet buffer adapted for caching the network traffic received from or sent to the server, and an Ethernet controller adapted for interfacing with the network. The server also includes a hypervisor coupled to one or more virtual machines (VMs) and a NIC driver adapted for interfacing with and supporting the accelerated NIC, wherein the NIC driver includes logic adapted for managing operations of the accelerated NIC.

Abstract: Exemplary embodiments of a system and method enable application of policy using Layer 2 fields for a data frame, simplified data structures, or both. In accordance with one aspect of the present invention, a policy may be based upon a destination address (DA), a source address (SA), or a virtual local area network identification (VID) associated with a data frame.

Abstract: Some embodiments provide a program for managing several switching elements. The program receives, at a network information base (NIB) data structure that stores data for managing the several switching elements, a request to notify a first application that uses the NIB when a set of data stored in the NIB is changed. The program changes, in response to an instruction from a second application, the set of data in the NIB. The program sends a notification to the first application of the change to the set of data in the NIB.

Abstract: A method, a device and a system for establishing a Pseudo Wire (PW) are provided. The method includes: receiving, by a switching node, a control message; constructing a first control message according the first FEC information and the routing information in the control message, and sending the first control message to a second terminal node; constructing, by the second terminal node, a second control message, where the second control message includes the second FEC information and the second routing information, and the second FEC information carries identification information of the first terminal node; and sending the second control message to the switching node. In the method, it is unnecessary to manually configure a PW routing table on the switching node or establish a PW routing table dynamically through a routing protocol, and it is unnecessary to configure mapping relations between PW segments manually. This method achieves robust maintenance.

Abstract: A system for operating a plurality of information handling systems forming a network including a plurality of switches is provided. The switches include physical and virtual switches each having ports coupling information handling systems to one another. The system including a management unit configured to provide commands to the switches and to collect a status information for each of the switches; and an agent unit coupled to each of the switches, the agent configured to receive the commands from the management unit, provide the commands to the switch associated thereto, monitor status of the switch associated thereto, and provide the status information to the management unit. A method for operating a network and a computer program to perform the method for using a system as above is also provided. A network managing device configured to couple to a service provider in a network as above is also provided.

Abstract: A method that improves multi-area routed Ethernet network design, in which multipath implementation in each of the areas is independent of each other area to allow optimal network design in each area. The network implements a shortest path bridging medium access control (SPBM) protocol. The areas include a Level 2 (L2) routing area coupled to a Level 1 (L1) routing area via multiple area border bridges (ABBs). The L1 routing area including a backbone edge bridge (BEB) coupled to the ABBs via multiple L1 multipath instances identified by respective backbone VLAN identifiers (B-VIDs). The ABBs receive an advertisement from the BEB that indicates a set of BEB identifiers, each of which identifies the BEB and is associated with a respective B-VID. Each of the BEB identifiers is unique. The ABBs also advertise into the L2 routing area, and translate the B-VIDs based on service identifiers for frames transiting the ABBs.

Abstract: A method, device, and system for processing Border Gateway Protocol (BGP) route are provided, which relate to the field of network communication technologies. The method includes: receiving a BGP route sent by a BGP neighbor; obtaining a route prefix of the BGP route according to the BGP route; determining, according to the route prefix, a BGP route storing and processing module corresponding to the route prefix; and sending the BGP route to the determined BGP route storing and processing module, so that the BGP route storing and processing module processes the received BGP route. A device and a system for processing BGP route are also provided. Therefore, the processing efficiency of the BGP route is improved, and the high extensibility is realized.

Abstract: An apparatus comprising a path computation element (PCE) configured to communicate with a path computation client (PCC) and compute a point-to-multipoint (P2MP) path across an autonomous system (AS) domain. Also included is a network component comprising at least one processor configured to implement a method comprising obtaining a computation request for a P2MP path across a plurality of AS domains, attempting to calculate the P2MP path across the AS domains, thereby generating a computed path or a failure reason, and transmitting a reply comprising the computed path or an indication of the failure reason. Included is a method comprising exchanging a request message and a reply message about a P2MP path across an AS domain between a PCC and a PCE.

Abstract: In one embodiment, a network device in a set of network devices obtains a pseudowire label for a Provider Edge (PE) device, where the pseudowire label corresponds to a Virtual Local Area Network (VLAN) on the PE device. In addition, the network device obtains a set of one or more MAC addresses reachable via the PE device, wherein the set of network devices support Ethernet Virtual Private Network (E-VPN) and are in the same redundancy group such that the set of network devices are coupled to the same customer edge device. The network device stores the pseudowire label in association with the set of one or more MAC addresses. The network device uses the pseudowire label to encapsulate traffic associated with the VLAN that is received from the customer edge device and destined to the set of MAC addresses reachable via the PE device.

Abstract: An edge device searches a MAC table to obtain information of a public network egress interface for a packet which is to be sent from a local site to a remote site to access a service, replaces a VLAN ID in the packet with a VLAN ID used for transmission in a public network, and sends the packet in which the VLAN ID has been replaced to a remote site according to the information of the public network egress interface.

Abstract: Systems and methods for the management of virtual machine instances are provided. The hosted virtual machine networks are configured in a manner such that communications within the hosted virtual machine network are facilitated through a communication protocol. Illustrative embodiments of the systems and methods may be implemented on a virtual network overlaid on one or more intermediate physical networks that are used as a substrate network. Through the utilization of one or more virtual network mapping components in communication with the hosted virtual network components, communications to and from the hosted virtual networks can be processed by mapping relationships between the virtual network communication protocol and the router communication protocol. The mapping information can be provided in advance or as requested to the router components and hosted virtual network components to facilitate bi-lateral communications between the components.

Abstract: In one embodiment, a data packet is received at a network device. A layer-2 identification (L2ID) value is identified for the received data packet based on a destination address and a label stack of the received data packet. The L2ID value is specific to an application associated with the data packet. A 6-tuple is created that includes the L2ID value. The received data packet is classified using the 6-tuple. Deep packet inspection (DPI) services are performed based on the classification of the received data packet. The DPI services apply a set of one or more application-level policies to the received data packet. The received data packet is forwarded from the network device toward a destination.

Abstract: A communication method includes determining a difference state of identification numbers of communication providers corresponding to a plurality of relay transfer apparatuses on a passing outward path to an opposing communication apparatus and on a passing return path from the opposing apparatus; and switching a first virtual communication channel set between intranets and a second virtual communication channel set between the intranets to dynamically substitute and use a first communication mode of transmitting and receiving encrypted communication data to and from the opposing apparatus through the first virtual communication channel and a second communication mode of transmitting and receiving plain text communication data to and from the opposing apparatus through the second virtual communication channel, according to the determination of the difference state of the identification numbers of the providers.

Abstract: A distributed switch may include a hierarchy with one or more levels of surrogate sub-switches (and surrogate bridge elements) that enable the distributed switch to scale bandwidth based on the size of the membership of a multicast group. When a sub-switch receives a multicast data frame, it forwards the packet to one of the surrogate sub-switches. Each surrogate sub-switch may then forward the packet to another surrogate in a different hierarchical level or to a destination computing device. Because the surrogates may transmit the data frame in parallel using two or more connection interfaces, the bandwidth used to forward the multicast packet increases for each surrogate used.

Abstract: Systems and methods for communication. A network abstraction layer (NAL) is built on a public Internet; and a network virtualization layer (NVL) is built on the NAL.

Abstract: A method of routing internal network traffic within a computing system comprises receiving a network packet at a configurable logic device (CLD), parsing the network packet to obtain a destination address, searching a predetermined range of a routing table wherein each row of the routing table specifies a range of possible destination addresses and routing information, identifying a matching row of the routing table wherein the destination address falls within the range of possible destination addresses of the matching row, and routing the packet according to the routing information.

Abstract: A new type of Provider Edge (PE) device is used to support BGP-based IP-VPNs. Each VRF instance in a PE device is associated with a dedicated IP address (Service IP address). Each service IP address is dedicated to a VRF in a PE device. The service IP address is distributed by BGP for VPN route association. Customer/VRF IP packets can be sent to a VRF instance in the egress PE device using service IP header encapsulation (with IP Destination Address=Service IP address of egress PE's VRF & IP Source Address=Service IP address of ingress PE's VRF). This obviates the need for explicit tunnels in the core.

Abstract: A network node for forwarding a data packet to a virtual network. The network node may maintain a table comprising one-to-one mapping information between one or more virtual private network (VPN) labels and one or more identifying labels for a destination virtual network. The network node may receive a data packet from a Multiprotocol Label Switching (MPLS) network. The data packet may comprise one or more VPN labels, at least one of which may be a MPLS Big Label Value that supports one-to-one mapping for more than one million destination virtual network addresses. The MPLS Big Label Value may comprise a destination virtual network address. The network element may map the one or more VPN labels to corresponding identifying labels for the destination virtual network according to the table, and forward the data packet to the destination virtual network.

Abstract: In a system, the functionality is decentralized in a data transmission network so that the need of communications produced by and addressed to data terminals to pass by way of a single point in the data transmission network is diminished. A first data transmission installation is adapted to signal second data transmission installations, each of which is part of a ring-shaped data transmission topology, to be capable of building logical data transmission tunnels directed to the data terminals. Thereby, all the logical data transmission tunnels need not commence or, depending on the direction, terminate at the same point of a data transmission network. In addition, the data transmission installations present in a ring-shaped data transmission topology need not necessarily be taught routing information in order to enable each of these data transmission installations to send data transmission frames to be transmitted to another one of these data transmission installations.

Abstract: A network function virtualization device includes at least one network function virtual machine; and a network function flow switch configured to receive flows and to switch the flows to the at least one network function virtual machine, and a network functions virtualization method for applying the virtualized network function to the flows.

Abstract: Methods and apparatus for segregating traffic are disclosed. In accordance with one embodiment, a traffic splitter identifies a set of links coupled to the traffic splitter, where the set of links includes two or more uplinks, wherein each of the two or more uplinks are implemented in a common physical media. The two or more uplinks include a LAN uplink coupled to a LAN and a SAN uplink coupled to a SAN. The traffic splitter prevents SAN traffic from reaching the LAN via the LAN uplink. In addition, the traffic splitter prevents LAN traffic from reaching the SAN via the SAN uplink.

Abstract: A distributed switch may include a hierarchy with one or more levels of surrogate sub-switches (and surrogate bridge elements) that enable the distributed switch to scale bandwidth based on the size of the membership of a multicast group. When a sub-switch receives a multicast data frame, it forwards the packet to one of the surrogate sub-switches. Each surrogate sub-switch may then forward the packet to another surrogate in a different hierarchical level or to a destination computing device. Because the surrogates may transmit the data frame in parallel using two or more connection interfaces, the bandwidth used to forward the multicast packet increases for each surrogate used.

Abstract: Aggregation switches are connected to an edge node by a multi-chassis link aggregation group and a virtual fiber link provides a connection for exchange of information between the aggregation switches regarding MAC addressing to synchronize MAC address tables across the aggregation switches. When failure of the virtual fiber link is detected, the multi-chassis link aggregation group is reconfigured into two or more link aggregates with each link aggregate connecting the edge node to one of the aggregation switches. A spanning tree protocol is initiated over the link aggregates to prevent loops in the network. MAC address tables are flushed and relearned with the two or more link aggregates.

Abstract: A network relay device includes a communication unit, an authentication processing unit, a DHCP snooping processing unit, and a terminal search processing unit. The authentication processing unit creates first information specifying an authenticated terminal device according to web authentication, and manages whether relay of communication data between a terminal device and a node on the specified network is permissible based on the first information. The DHCP snooping processing unit executes snooping of DHCP communication data between a terminal device and a DHCP server, and creates second information specifying a layer 3 address allocated to each terminal device. The terminal search processing unit specifies an authenticated terminal device based on the first information, specifies a layer 3 address allocated to the specified authenticated terminal device based on the second information, and causes the communication unit to send, to the specified layer 3 address, confirmation communication data.

Abstract: A management server includes a configuration and management module processing server configuration information, including a VPN peer list and VLAN/subnet settings. The management server automatically calculates the VPN configuration information, including the VPN peer subnet route information identifying which of the subnets participating in the VPN are behind which of the routers and keys to establish VPN tunnels between those routers participating in the VPN. Each of the routers participating in the VPN includes a VPN tunnel with the other routers participating in the VPN, a set of data structures storing data identifying contact information for each of the subnets participating in the VPN, a combination of an IP address and port to reach one of routers that that subnet is behind, and a forwarding module to forward traffic between the subnets.

Abstract: Systems and methods for network assignment based on priority are described in this application. In one aspect, a technique for network assignment based on priority relates to establishing a connection between a client and a virtual local area network (VLAN), based on an explicit or implicit network priority preference of the client. In an embodiment, multiple VLANs can be combined into one network bundle, the network bundle being a unit network for priority specification. In addition, multiple network bundles may be available for network assignment on a particular network controller (e.g., network switch). For example, the preferred network of a client may be comprised of several individual VLANs. Thus, the client can be assigned to any of the constituent VLANs included in the preferred network bundle.

Abstract: A method performed by a provider edge device includes generating pseudo-wire tables based on virtual private local area network service advertisements from other provider edge devices, where the provider edge device services customer edge devices, and establishing pseudo-wires with respect to the other provider edge devices, based on the pseudo-wire tables, where the pseudo-wires include an active pseudo-wire and at least one standby pseudo-wire with respect to each of the other provider edge devices. The method also includes generating and advertising VPLS advertisement to the other provider edge devices, detecting a communication link failure associated with one of the customer edge devices in which the provider edge device services, and determining whether the at least one standby pseudo-wire needs to be utilized because of the communication link failure.

Abstract: An apparatus comprising a plurality of district boundary bridges (DBBs) in a plurality of second network districts configured to couple to a plurality of core bridges in a core network district and to a plurality of end-stations in the second network districts via a plurality of intermediate switches in the second network districts; wherein the core bridges and the DBBs are aware of a plurality of Media Access Control (MAC) addresses of the DBBs but are not aware of Internet Protocol (IP) addresses and MAC addresses of the end-stations, and wherein the IP addresses of the end-stations are mapped in a directory service (DS) in the core network district to the MAC addresses of the corresponding DBBs in the corresponding second network districts of the end-stations.

Abstract: Systems and methods are described for managing a wireless network. Packets addressed to subscriber stations may be assigned a tag based on the base station at which the packet is received and the base station at which the subscriber station first entered the network. The tag can identify a media access address associated with subscriber equipment accessible through the subscriber station and an IP address associated with the subscriber equipment. The tag may be obtained from a table linking each of a plurality of virtual local area networks to one or more subscriber stations previously registered at a network base station.

Abstract: In an embodiment, a method is provided at which it is used in a device. In this method, a logical identifier assigned to the device is identified and additionally, a mesh group identifier identifying a mesh group is identified. The logical identifier and the mesh group identifier are encoded in a routing message, which is used in an inter-domain routing protocol, and this routing message is transmitted to a reflector device in communication with the device. The reflector device is configured to transmit the routing message to a remote device included in the computer network.

Abstract: Systems and methods are provided for operating a network arrangement including multiple network devices that are coupled to each other in a ring structure. Each network device includes a control device and a switch device with at least two ports for coupling to a communication path. During operation, at least two VLANs are simultaneously provided in the ring structure, and the sending of a data packet from the control device of a selected network device is performed via a port of the switch device in one of the two VLANs. In order to achieve this, the other port of the switch device of the selected network device is deactivated for the one VLAN. By using two VLANs, a redundant and reliable data transmission may be achieved. A destabilization of the VLANs in the network ring is prevented by the targeted deactivation of specific ports of the sending network device.

Abstract: Methods and systems for selectively processing VLAN traffic from different networks while allowing flexible VLAN identifier assignment are disclosed. According to one aspect, a layer 2 switch includes a virtual switch identifier data structure that associates a VLAN identifier extracted from a layer 2 frame and a port identifier corresponding to a port on which a frame is received with a virtual switch identifier. The virtual switch identifier is used to select a per-virtual-switch data structure, such as a forwarding table. The per-virtual-switch data structure is used to control processing of the layer 2 frame on a per-virtual-switch basis. The per-virtual-switch data structure may also be updated separately from the data structures assigned to other virtual switches.

Abstract: Systems, mechanisms, apparatuses, and methods are disclosed for dynamically tagging VLANs. For example, in one embodiment such means include: means for receiving a packet having identified therein a source Media Access Control (MAC) address and a Virtual Local Area Network (VLAN) Identifier, wherein the VLAN identifier corresponds to a VLAN which is non-existent on a network switch; means for modifying the packet received to include two VLAN tags, a first VLAN tag corresponding to the VLAN identifier identified within the packet received and a second VLAN tag, distinct from the first; means for determining no forwarding database entry exists for the modified packet; and means for creating the VLAN on the network switch to handle received packets tagged with the VLAN identifier.

Abstract: A composite quality measure helps determine a target for a vertical handover between different connection types. Various measurements are normalized, weighted and summed to produce composite quality measures. A composite quality measure may be compared to a target value and the corresponding connection may be added to a feasibility table if the composite quality measure is above the target.

Abstract: A device provides layer two (L2) services between customer networks that are coupled by one or more intermediate computer networks. The device comprises a routing process that receives label information for a label switched path (LSP) through the intermediate networks. The device further comprises a L2 service that receives L2 service information from a device associated with second customer networks. In accordance with the label information, the device transports L2 communications between the first and second customer networks through the one or more intermediate networks. By utilizing label information in this manner, the device may minimize the impact of providing L2 services through the intermediate networks.

Abstract: A processor determines, when a frame is received, whether a total of current learning numbers stored in a second storage unit has reached a total of maximum learning numbers. The processor identifies in the second storage unit, if it is determined that the total of current learning numbers has reached the total of maximum learning numbers, a first group identifier associated with a lower priority than a priority associated with a reception group identifier contained in the frame. The first group identifier is associated with a first current learning number not less than a first minimum learning number associated with the first group identifier. The processor replaces a first correspondence relationship including the first group identifier with a reception correspondence relationship among a port number of a port at which the frame has been received, a source address contained in the frame, and the reception group identifier.

Abstract: One embodiment of the present invention provides a switch system. The switch includes one or more ports on the switch configured to transmit packets encapsulated based on a first protocol. The switch further includes a control mechanism. During operation, the control mechanism forms a logical switch based on a second protocol, receives an automatically assigned identifier for the logical switch without requiring manual configuration of the identifier, and joins a virtual cluster switch.

Abstract: A method, apparatus and computer program product for providing Routed Split Multi Link Trunking (RSMLT) for Wireless Local Area Network (WLAN) tunnels is presented. A first and second network switch learn data associated with each other, wherein the first network switch and the second network switch operate concurrently. The first network switch terminates a WLAN Tunnel. The data is synchronized between the first network switch and the second network switch, wherein the data includes MAC Addresses, Internet Protocol (IP) interface addresses, Virtual Local Area Network (VLAN) associations, WLAN tunnel assignments and Network switch Internet Protocol (IP) addresses. Load sharing of tunnel data packets is performed by the first and the second network switch. Tunnel control packets received by the second network switch are forwarded to the first network switch over an Inter Switch Trunk (IST).

Abstract: A control plane of a logical network device creates a service link aggregation group and adds one port from each member network device to the service link aggregation group. The logical network device includes member network devices and each port connects the logical network device to the same neighbor device. When a port of the logical network device receives a message with an unknown source address, the control plane determines if the receiving port is in any service link aggregation group. After determining the receiving port is in the service link aggregation group, the control plane configures a data plane of the logical network device with mappings between the address and the ports in the service link aggregation group.

Abstract: A system and method can support virtual network interface card (NIC) failover in a middleware machine environment. The middleware machine environment includes a local management node and a remote management node. The system provides a local NIC driver and a remote proxy instance on a local management node. The remote proxy instance can associate a machine address with a remote NIC driver on a remote management node that is connected with the local remote management node in a subnet. Furthermore, the remote proxy instance operates to direct packets to and from the remote NIC driver using the machine address.

Abstract: The present invention provides methods and devices for implementing a Low Latency Ethernet (“LLE”) solution, also referred to herein as a Data Center Ethernet (“DCE”) solution, which simplifies the connectivity of data centers and provides a high bandwidth, low latency network for carrying Ethernet and storage traffic. Some aspects of the invention involve transforming FC frames into a format suitable for transport on an Ethernet. Some preferred implementations of the invention implement multiple virtual lanes (“VLs”) in a single physical connection of a data center or similar network. Some VLs are “drop” VLs, with Ethernet-like behavior, and others are “no-drop” lanes with FC-like behavior. Some preferred implementations of the invention provide guaranteed bandwidth based on credits and VL. Active buffer management allows for both high reliability and low latency while using small frame buffers. Preferably, the rules for active buffer management are different for drop and no drop VLs.

Abstract: One embodiment of the present invention provides a switch. The switch includes a gateway subgroup module, a tunnel management module, and a packet processor. The gateway subgroup module operates the switch in conjunction with a remote switch to form a gateway subgroup. The switch and the remote switch actively operate as tunnel gateways. The tunnel management module maintains a data structure indicating whether a tunnel source subnet is associated with the gateway subgroup. The packet processor decapsulates a tunnel-encapsulated packet in response to a tunnel source subnet of the tunnel-encapsulated packet being associated with the gateway subgroup.

Abstract: A method of communications at an encapsulating bridge includes receiving a packet having an unencapsulated-DA (destination address) and an associated encapsulation identifier. The unencapsulated-DA and the associated encapsulation identifier are used to determine a TxPort-unencapsulated network (unencapsulated network side transmit port) or an encapsulated-DA for the packet. This method reduces latency of processing by reducing lookups, thereby also increasing transmission bandwidth of the communications network. The invention also facilitates embodiments with reduced memory and processing requirements, as compared to conventional implementations. This method is particularly useful for MAC-in-MAC encapsulation.

Abstract: Various embodiments are disclosed for encoding and decoding VLAN identifiers. One such method includes mapping the VLAN identifier, associated with the frame, to a number of extra bytes. The method also includes appending, to the payload, a quantity of bytes equal to the number of extra bytes. The method also includes setting at least one of the appended bytes to a value of a length provided with the frame. The method also includes transmitting the frame, including the appended bytes.

Abstract: Some embodiments provide a distributed control system for controlling managed switching elements of a network. The distributed control system comprises a first controller for converting a first set of input logical control plane data to a first set of output logical forwarding plane data. It also includes a second controller for converting a second set of input logical control plane data to a second set of output logical forwarding plane data. The logical forwarding plane data is translated into physical forwarding behaviors that direct the forwarding of data by the managed switching elements.

Abstract: In a network device such as a network switch having a port coupled to a communications medium dedicated to a single virtual local area network and another port coupled to a communications medium shared among multiple virtual local area networks for transmitting data frames between the dedicated communications medium and the shared communications medium, a method of identifying the virtual network associated with each data frame received by the network switch when transmitting the data frames over the shared communications medium. The method comprises receiving data frames from the dedicated communications medium coupled to one port, and, with respect to each data frame so received, inserting a new type field and a virtual network identifier field. The contents of the new type field indicate the data frame comprises a virtual network identifier field.