摘要:
A mobile customer service station operating within a wireless multi-hop communication network includes a console on a wheeled chassis. The console carries and houses a number of components which are used in merchandising operations to conclude customer purchase transactions. The items supported externally on the console are a printer for printing purchase receipts, customer credit charge agreements and records of transactions, and a magnetic card reader for reading information from a magnetic stripe of a customer's credit card. In one embodiment, the operation of the printer, credit card reader and the cash drawer is controlled by a multi-function control unit located within an enclosure of the console. The control unit is electrically powered by a self-contained power source which is preferably a deep cycle rechargeable battery. The console also houses a transceiver unit which under the control of the control unit is capable of interactive communication with a premises network. In another embodiment, the mobile service station comprises an access device which participates with a variety of peripherals at the station in a lower power communication LAN, while providing higher power communication to other network devices via a premises network with routing via a wireless spanning tree configuration.
摘要:
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. If a wireless device configured with a VLAN ID is attached to an access point with a matching VLAN ID, or if the wireless device is attached to a non-VLAN access point, then the wireless device may send and receive raw/untagged frames. In addition to the gateways described below, the ability of a wireless device to detect when it can send untagged frames is considered novel. In another embodiment of the invention, a special ID that is different than the native VLAN ID for a switch port is used for VLAN-unaware devices. This allows such devices that do not issue tagged frames to belong to a single VLAN ID.
摘要:
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.
摘要:
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. Additionally, redundant network and communication protocol is disclosed wherein the 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. 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.
摘要:
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.
摘要:
A mobile customer service station operating within a wireless multi-hop communication network includes a console on a wheeled chassis. The console carries and houses a number of components which are used in merchandising operations to conclude customer purchase transactions. The items supported externally on the console are a printer for printing purchase receipts, customer credit charge agreements and records of transactions, and a magnetic card reader for reading information from a magnetic stripe of a customer's credit card. In one embodiment, the operation of the printer, credit card reader and the cash drawer is controlled by a multi-function control unit located within an enclosure of the console. The control unit is electrically powered by a self-contained power source which is preferably a deep cycle rechargeable battery. The console also houses a transceiver unit which under the control of the control unit is capable of interactive communication with a premises network. In another embodiment, the mobile service station comprises an access device which participates with a variety of peripherals at the station in a lower power communication LAN, while providing higher power communication to other network devices via a premises network with routing via a wireless spanning tree configuration.
摘要:
A mobile customer service station operating within a wireless multi-hop communication network includes a console on a wheeled chassis. The console carries and houses a number of components which are used in merchandising operations to conclude customer purchase transactions. The items supported externally on the console are a printer for printing purchase receipts, customer credit charge agreements and records of transactions, and a magnetic card reader for reading information from a magnetic stripe of a customer's credit card. In one embodiment, the operation of the printer, credit card reader and the cash drawer is controlled by a multi-function control unit located within an enclosure of the console. The control unit is electrically powered by a self-contained power source which is preferably a deep cycle rechargeable battery. The console also houses a transceiver unit which under the control of the control unit is capable of interactive communication with a premises network. In another embodiment, the mobile service station comprises an access device which participates with a variety of peripherals at the station in a lower power communication LAN, while providing higher power communication to other network devices via a premises network with routing via a wireless spanning tree configuration.
摘要:
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.
摘要:
A power-save method for a network with an access point and an associated power-save client. The access point buffers wireless data that includes a unicast frame and a multicast frame. A periodic scheduled beacon message is transmitted with a unicast indication element and a multicast indication element. The unicast element instructs a client to remain awake to receive a buffered unicast frame, which includes a destination MAC address. The multicast element instructs a client to remain awake following the beacon to receive a buffered multicast frame, which includes a destination multicast address designating a multicast group of which the client is a member. At least one beacon message is designated as a multicast delivery beacon. The buffered multicast frame is transmitted following the designated multicast beacon. The multicast element contains a list of entries, each entry corresponding to either a multicast MAC address, multicast IP address, or client identifier.
摘要:
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.