Abstract: When multi-destination traffic is distributed through a host or switch, the decision to distribute each frame is performed by each egress port and not the ingress port. Within a link aggregation group, the multi-destination frame is sent to each of the egress ports within the link aggregation group. Each of such ports will then determine whether it should re-transmit the frame. If not, the frame is discarded.

Abstract: In a data communication internetwork including a source station, an end station, and a default router for the source station, a default communication path including the default router is defined between the source station and the destination station. During operation of the data communication internetwork, a shortcut data communication path by passing the default router is established between the source station and the destination station, such that data packets transmitted by the source station are not received by the default router. After the shortcut communication path has been established, a control frame containing source-route information regarding the source station is transmitted to the router, and the source-route information is stored at the router.

Abstract: A method for providing interoperability between multiple versions of LUNI within a mixed Asynchronous Transfer Mode emulated LAN is disclosed. The mixed ATM emulated LAN includes multiple LAN emulated clients (LE clients) having different versions of LAN Emulation User Network Interface (LUNI), such as a first version LUNI and a second version LUNI. The mixed ATM emulated LAN is served by a LAN Emulation Server (LES), a Broadcast and Unknown Server (BUS), and a LAN Emulation Configuration Server (LECS). When an LE Control Frame is being sent by an LE client having a second version LUNI, a determination is made as to whether or not the LE Control Frame will be received by an LE client having a first version LUNI.

Abstract: A method of alleviating network congestion in an emulated Local Area Network (ELAN) within an Asynchronous Transfer Mode (ATM) network is implemented. The method mitigates network congestion by distributing the connection times of Local Area Network (LAN) Emulation Client (LEC) to an ELAN over random periods of time. When a LAN Emulation Server (LES) or Broadcast and Unknown Server (BUS) attempts to build point-to-multipoint connections to the LEC, it issues control messages to network switches. If the messages are dropped or rejected the LES or BUS recognizes the network is in a congested state and randomly retries to attempt connection.

Abstract: A communication network having a plurality of routers, each connected to host systems by LAN networks and interconnected by a switched network uses a shared or common IP and MAC address in the routers. Host systems on the same subnet use the shared or common IP address as their default gateway address when accessing host systems on another subnet.

Abstract: A method is implemented to enable networks employing source-route bridging to participate in route switched, Asynchronous Transfer Mode (ATM), networks. Such source-routed networks, for example, Token-Ring LANs, incorporate an end-to-end route description in the data packets transmitted by the source station. The end-to-end route description is contained in a Route Information Field (RIF). The method implemented herein associates an RIF with the ATM address corresponding to a destination station. This permits the source-route bridged network to exploit the efficiencies of layer-2 connections and the high-speed switching characteristics of the ATM network.

Abstract: A communication network having a plurality of routers, each connected to a host system by a LAN network and interconnected by a switched network, the common network using a shared or common IP and MAC address in the routers forming a subnet. Host systems on the same subnet use the shared or common IP address as their default gateway address when accessing host systems on another subnet.

Abstract: An ATM communications network with several ELANs allows steady-state data to be passed between ATM attached devices which bypasses intermediate LECs and bridges. Connected to the ATM communications network is a bridge unit which includes a bridge and associated LECs. Also, an origination ATM attached device and a destination ATM attached device are attached to the ATM communications network via a first by a first ELAN and a second ELAN, respectively. The origination ATM attached device sends a request for an ATM address associated with the destination ATM attached device to the bridge, via the first ELAN. After some processing, the bridge returns the ATM address associated with the destination ATM attached device to the origination ATM attached device. This allows the origination ATM attached device to establish a shortcut VCC with the destination ATM attached device using the ATM address associated with the destination ATM attached device, thereby bypassing intermediate bridges and LECs.

Abstract: An ELAN having redundant default gateways is attached to an asynchronous transfer mode (ATM) communications network. The ELAN's redundant default gateways are comprised of a first and second routers. The first router is associated with a primary default gateway and the second router is associated with a backup default gateway. Both the primary and backup default gateways are connected to the ELAN and both the primary and backup default gateways are configured with a default gateway IP address and associated MAC address. Initially, the primary default gateway registers the default gateway MAC address, thereby becoming the active default gateway. While the primary default gateway is active, the backup default gateway continually attempts to register the default gateway MAC address.

Abstract: Provided are a method and system that allow one or more network protocol emulators, composed of one or more network protocol emulation controllers and one or more network protocol emulation entities, which are overlaid onto the one or more base networks utilizing different communications protocols for the purpose of allowing said one or more networks to be accessed and utilized as if the one or more networks were utilizing protocols emulated by the one or more network protocol emulators. The method and system utilize the following steps. Apprising the one or more network protocol emulation controllers of network capability information inherent within protocols utilized by the one or more networks onto which the one or more network protocol emulation controllers are overlaid.

Abstract: A primary ARP server and a backup ARP server are connected to an ATM communications network. The primary and backup ARP servers each have associated ATM addresses. Also, a LIS is connected to the ATM communications network. Either the primary or backup ARP server is the active ARP server and resolves IP addresses to ATM addresses for the LIS. When the backup ARP server recognizes the removal of a redundancy virtual channel connection (VCC) between the backup ARP server and the primary ARP server, the backup ARP server registers using the ATM address associated with the primary ARP server. This allows the backup ARP server to take over for the primary ARP server to become the active ARP server.In addition, a primary default gateway and a backup default gateway are connected to the ATM communications network. These default gateways have associated ATM addresses. One of the primary and backup default gateways is active at a time.

Abstract: To ensure a LES issues address resolution responses when necessary, an association between a MAC/ATM address pair and an intersubnet shortcut virtual channel connection (VCC) is registered. When the LES receives a first data frame being sent from a first station to a second station, with the second station having a MAC address associated with a shortcut VCC, a second data frame is created. The second data frame has as a source address the MAC address. The second frame is sent to devices associated with the first station so that the devices may learn the origination point for the second station and can issue messaging necessary to establish an shortcut VCC. In addition, frame loss reduction in an ATM communications network is accomplished by registering an association between a MAC address of a router associated with a MAC/ATM address pair, and a shortcut VCC. After the association is registered, a data frame being sent from a first station to a second station is received.

Abstract: Provided are a method and system for achieving enhanced performance in communications involving one or more emulated networks overlaid onto at least one base network, where the emulation is performed by one or more network emulation servers-broadcast and unknown servers. The objects of the method and system are achieved via the following. Monitoring addresses of data transiting the one or more network emulation servers-broadcast and unknown servers where such monitored addresses are indicative of one or more functions provided by the one or more emulated networks. Tracking the monitored addresses. Comparing the tracked addresses, indicative of on or more functions provided by the one more emulated networks, with one or more prespecified thresholds indicative of monopolization of resources of the at least one emulated network.