Abstract: Disclosed herein is a redundant network and communication protocol at least including host computers, RF base stations, and roaming terminals. The network may utilize a polling communication protocol such that under heavy traffic conditions, a roaming terminal wishing to initiate communication may be required to determine whether the channel is clear by listening for an entire interpoll gap time. When a hidden terminal is communicating, the roaming terminal may conclude that the communication is taking place upon receiving a polling frame directed to the hidden terminal from the normally silent base station. Inherent redundancy techniques may be used with a spanning tree approach for determining the most efficient pathways from a source to a destination and ensuring that the network adapts to spatial changes or breakdowns within the network.

Abstract: A method for multicast load balancing in a wireless network having a plurality of access points. The method includes setting a maximum Internet protocol multicast bandwidth for the access points, receiving an admissions control request from a client at one of the access points, and determining whether the admissions control request from the client is for an admitted or unadmitted multicast stream at the access point. The access point is responsive to the admissions control request for the admitted multicast stream by servicing the admitted multicast stream and to the admissions control request for the unadmitted multicast stream by servicing the unadmitted multicast stream where the bandwidth required for the unadmitted multicast stream, plus that portion of the access point bandwidth currently used for all existing downlink multicast streams, does not exceed the maximum internet protocol multicast bandwidth for the access point.

Abstract: A method and implementation are disclosed for binding a mobile node to a subnet. The invention comprises steps and implementations for intercepting messages sent by a mobile node to a server, associating a predetermined subnet with the intercepted messages and forwarding the intercepted messages to the server. The invention intercepts reply messages sent by at least one server, selects reply messages that are associated with the predetermined subnet. The selected reply messages are forwarded to the mobile node and reply messages that are not associated with the predetermined subnet are discarded.

Abstract: A system and method for aggregating multiple radio interfaces into a single logical bridge interface with reference to an IEEE 802.11 Wi-Fi network and an Ethernet local area network. The system includes a master switch with multiple associated wireless modules. Each master switch wireless module selectively broadcasts an associated connection signal. The master switch has an associated aggregation port, which is in data communication with each of the master switch wireless modules and selectively routes data among the master switch wireless modules. The system also includes a slave switch with multiple associated wireless modules. Each of the slave switch wireless modules receives one associated connection signal and establishes a wireless data communication link with the broadcasting master switch. The slave switch also includes an associated aggregation port, which is in data communication with each of the slave switch wireless modules, selectively routes data among the slave switch wireless modules.

Abstract: A method providing quality of service during a contention period. A tiered access protocol enables an Access Point to act as a channel arbitrator and gain control a channel during a contention period. The Enhanced Access Point waits a specified amount of time after before taking control of a channel for either transmitting an outbound frame or initiating Polled-Contention Free Bursts. In addition, a method for increasing the time span between Delivery Traffic Indication Message beacons by tracking when Wireless Stations are able to receive messages and instantly delivering messages to those Wireless Stations.

Abstract: A system for providing a Virtual Local Area Network (VLAN) by use of an encryption states or encryption keys for identifying a VLAN. A table of data including a VLAN and an associated encryption state or key is provided for assignment of encryption states or keys, for devices in a wireless local area network.

Abstract: A protocol that enables an 802 mobile host to obtain a “home IP address,” and other configuration parameters via DHCP or BOOTP, while attached to either its home subnet or a foreign subnet. Inner and outer encapsulation headers are used to forward DHCP messages from a DHCP server outbound through a “forward tunnel,” to a mobile host on a foreign subnet and are also used to forward DHCP messages from a mobile host on a foreign subnet inbound through a “reverse tunnel” to the home subnet. A mobile host must add an inner encapsulation header to inbound DHCP packets with the source IP address set to 0 to indicate that the packet is from a mobile host that does not have a registered home IP address. Outer encapsulation headers contain the home address and the care-of address for the mobile host.

Abstract: A method and system of selective data transmission is disclosed. A plurality of data packets are transmitted wherein at least a portion of the data packets have one or more predetermined identifiers. The data packets having the predetermined identifier are selected and forwarded to a desired recipient.

Abstract: An apparatus and a method for routing data in a radio data communication system having one or more host computers, one or more intermediate base stations, and one or more RF terminals organizes the intermediate base stations into an optimal spanning-tree network to control the routing of data to and from the RF terminals and the host computer efficiently and dynamically. Communication between the host computer and the RF terminals is achieved by using the network of intermediate base stations to transmit the data.

Abstract: A hierarchical communication system, arranged in a spanning tree configuration, is described in which wired and wireless communication networks exhibiting substantially different characteristics are employed in an overall scheme to link portable or mobile computing devices. Copies of data, program code and processing resources are migrated from their source toward requesting destinations based on request frequency, communication link costs and available local storage and/or processing resources. Each appropriately configured network device acts as an active participant in network migration. In addition, portable two-dimensional (2-D) code reading terminals are configured to wirelessly communicate compressed 2-D images toward stationary access servers that identify the code image through decoding and through comparison with a database of images that have previously been decoded and stored.

Abstract: A communication system in which multiple protocols and proxy services are executed by an access point. In one embodiment of the invention, GVRP and GMRP registrations are combined in a single packet when a wireless device roams to a different VLAN. In addition, outbound GVRP and GMRP multicast messages are handled by an access point (also referred to as a GVRP and GMRP “gateway”) such that the wireless device is not burdened with the associated computational overhead. In a further embodiment, a wireless device may dynamically switch between a VLAN-aware state and a VLAN-unaware state depending on the nature of a detected access point. For example, if a relevant access point supports GVRP, the wireless device may operate as a VLAN terminal. If a wireless device is not attached to an access point with a matching VLAN ID, the wireless device sends and receives VLAN tagged frames.

Abstract: A method for associating a WSTA to a service set, wherein the service set is configurable at the AP. Each service set is an arbitrary grouping of one or more network service parameters, and is typically configured for either VLAN or proxy mobile IP host. When a wireless station desires to associate with an access point, the wireless station sends a message to the access point, the message containing a SSID. The access point then matches the SSID to a service set and associates the WSTA to either a home subnet or a VLAN based on the SSID. By locally configuring the service set, the default VLAN and home subnet for a WSTA may be different at each AP the WSTA encounters. A security server is configured with a list of allowed SSIDs for each wireless station to prevent unauthorized access to a VLAN or home subnet.

Abstract: An apparatus and a method for routing data in a radio data communication system having one or more host computers, one or more intermediate base stations, and one or more RF terminals organizes the intermediate base stations into an optimal spanning-tree network to control the routing of data to and from the RF terminals and the host computer efficiently and dynamically. Communication between the host computer and the RF terminals is achieved by using the network of intermediate base stations to transmit the data.

Abstract: A communication system in which multiple protocols and proxy services are executed by an access point. In one embodiment of the invention, GVRP and GMRP registrations are combined in a single packet when a wireless device roams to a different VLAN. In addition, outbound GVRP and GMRP multicast messages are handled by an access point (also referred to as a GVRP and GMRP “gateway”) such that the wireless device is not burdened with the associated computational overhead. In a further embodiment, a wireless device may dynamically switch between a VLAN-aware state and a VLAN-unaware state depending on the nature of a detected access point. For example, if a relevant access point supports GVRP, the wireless device may operate as a VLAN terminal. If a wireless device is not attached to an access point with a matching VLAN ID, the wireless device sends and receives VLAN tagged frames.

Abstract: An apparatus and a method for routing data in a radio data communication system having one or more host computers, one or more intermediate base stations, and one or more RF terminals organizes the intermediate base stations into an optimal spanning-tree network to control the routing of data to and from the RF terminals and the host computer efficiently and dynamically. Communication between the host computer and the RF terminals is achieved by using the network of intermediate base stations to transmit the data.

Abstract: A Mobile Ethernet Protocol that is used to logically extend a “home VLAN”, through an Ethernet/IP “campus network”, to mobile nodes on “foreign subnets”. The network architecture used for Mobile Ethernet is hierarchical and includes a Subnet Context Manager per subnet and a central Campus Context Manager. The protocol is generally based on the standard Mobile IPv4 protocol, but includes significant extensions to standard Mobile IP including using an 802 address as the permanent MN identifier, rather than an IP address, encapsulating and sending Ethernet frames through IP tunnels, and configuring a single Mobile Ethernet HA to provide access to multiple home VLANs wherein Home VLAN bindings for MNs are dynamically established. A MN does not need to be configured with a permanent IP address.

Abstract: A redundant network and communication protocol is disclosed having host computers, RF base stations and roaming terminals. In one embodiment, this network utilizes a polling communication protocol which, under heavy loaded conditions, requires that a roaming terminal wishing to initiate communication must first determine that the channel is truly clear by listing for an entire interpoll gap time. Thus, when a “hidden” terminal is communicating, the roaming terminal can conclude that such communication is taking place upon receiving a polling frame directed to that “hidden” terminal from the normally silent base station. In a further embodiment, a criterion used by the roaming terminals for attaching to a given base station reduces conflicts in the overlapping RF regions of adjacent base stations.

Abstract: A portable data terminal includes at least two communication transceivers having different operating characteristics, one for conducting data communications on a wired subnetwork and one for conducting data communications on a wireless subnetwork. A communication processor converts data received by the communication transceivers to a predetermined format for a base module and converts data in a predetermined format from the base module to a format for transmission by a selected one of the first and second communication transceivers, thereby isolating the base module from differing characteristics of the transceivers. The communication processor is arranged to relay communications received by one transceiver for re-transmission by the other transceiver and to transfer communications from one subnetwork to the other, without activating the base module.

Abstract: A hierarchical communication system, arranged in a spanning tree configuration, is described in which wired and wireless communication networks exhibiting substantially different characteristics are employed in an overall scheme to link portable or mobile computing devices. Copies of data, program code and processing resources are migrated from their source toward requesting destinations based on request frequency, communication link costs and available local storage and/or processing resources. Each appropriately configured network device acts as an active participant in network migration. In addition, portable two-dimensional (2-D) code reading terminals are configured to wirelessly communicate compressed 2-D images toward stationary access servers that identify the code image through decoding and through comparison with a database of images that have previously been decoded and stored.

Abstract: Improved apparatus for a radio communication system having a multiplicity of mobile transceiver units selectively in communication with a plurality of base transceiver units which, in turn, communicate with one or more host computers for storage and manipulation of data collected by bar code scanners or other collection means associated with the mobile transceiver units. A network controller and an adapter which has a simulcast and sequential mode provide selective interface between host computers and base transceivers. A scheme for routing data through the communication system is also disclosed wherein the intermediate base stations are organized into an optimal spanning-tree network to control the routing of data to and from the RF terminals and the host computer efficiently and dynamically.