Method and apparatus for reliable multicast communication over wireless network

(54) Title: METHOD AND APPARATUS FOR RELIABLE MULTIDIFUSION COMMUNICATION THROUGH WIRELESS NETWORK (30) Unionist Priority: 25/01/2007 us 11 / 657,544 (73) Owner (s): Intel Corporation (72) Inventor (s) : Benjamin Metzler, Christian Maciocco, Emily Qi (74) Attorney (s): Dannemann, Siemsen, Bigler & Ipanema Moreira (86) International Request: pct US2008051705 of 01/22/2008 (87) International Publication: wo 2008 / 09i893de 31 / 07/2008 (57) Summary: method and apparatus for RELIABLE BROADCASTING COMMUNICATION THROUGH WIRELESS NETWORK. The present invention relates to the method and apparatus, which are provided for reliable multicast communication over the wireless network. According to the modalities of the invention, the method includes determining a priority category for a multicast communication to be transmitted. The method includes designating, for multicast communication, one of the multicast communication containers as a leader based on the priority category and multicast diagnostic information from the multicast communication containers. The leader is assigned to transmit a receipt notice frame to the multicast communication source indicating the receipt of a multicast communication frame received from the source.

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Invention Patent Descriptive Report for METHOD E

RELIABLE BROADCAST COMMUNICATION APPLIANCE

THROUGH WIRELESS NETWORK.

Background of the Invention

Reliable multicast and diffusion of wireless communications is gaining importance as technology develops. In organizations, this can be exemplified by the fact that multicast and broadcast are becoming a required capability for live conference distribution, network training and wireless network management. On home networks, broadcast video sequencing can be used for home entertainment and games. In hospital settings, broadcasting can be used for commercials and television broadcasting.

Existing communication protocols such as the IEEE-Std 802.11 standard, Edition 1999 (ISO / IEC 8802-11: 1999) do not support reliable multicast / broadcast due to their inability to exchange acknowledgment messages (ACK) with multiple recipients . Achieving a level of reliability in multicast communication can be achieved by designating a determined wireless network, a leading station to respond to multicast traffic with an ACK, thereby notifying the multicast source that the packet has been successfully distributed to at least the leader. However, greater reliability can cause a longer delay or lower overall network throughput since reliability is achieved by retransmitting packets on the network.

Brief Description of Drawings

The matter considered the invention is particularly highlighted and distinctly claimed in the conclusive part of the specification. The invention, however, both with regard to the organization and method of the operation, together with its objectives, characteristics and advantages, can be better understood by reference to the following detailed description when dealing with the attached drawings in which:

figure 1 is a schematic block diagram of an illustrative wireless communication system according to some embodiments of the invention; and figure 2 is a schematic flowchart of a multicast communication method according to some modalities of the invention;

It will be appreciated that, for reasons of simplicity and clarity of illustration, elements illustrated in the figures were not drawn to scale, for example, the dimensions of some of the elements may be exaggerated in relation to other elements for reasons of clarity. In addition, where deemed appropriate, numerical references may be repeated between the figures to indicate corresponding or similar elements. Detailed Description of the Invention

In the detailed description that follows, numerous specific details are presented in order to provide an in-depth understanding of the invention. However, it will be understood by those skilled in the art that the invention can be practiced without these specific details. In other cases, well-known methods, procedures, components, units and / or circuits have not been described in detail so as not to obscure the invention.

The embodiments of the invention can provide a method for dynamically adapting a leader node designation for broadcast and multicast traffic on a wireless network through the use of network characterization and traffic type. According to the modalities of the invention, the method may include the designation for each multicast sequence an independent leader based on the characteristics of the traffic sequence and distribution requirement for the particular type of traffic.

The modalities of the invention can be used in various applications. Some embodiments of the invention can be used in conjunction with various devices and systems, for example, a transmitter, a receiver, a transceiver, a transmitter / receiver, a wireless communication station, a wireless communication device, an Access Point (AP), a modem, a wireless modem, a Personal Computer (PC), a desktop computer, a mobile computer, a laptop computer, a notebook computer, a tablet computer, a server computer, a portable computer, a portable device, a Personal Digital Assistant (PDA), a portable PDA device, a network, a wireless network, a Local Area Network (LAN), a wireless LAN (WLAN), a Metropolitan Area Network (MAN) , a Wireless MAN (WMAN), a Wide Area Network (WAN), a Wireless WAN (WWAN), devices and / or networks operating in accordance with existing IEEE 802.11, 802.11a, 802.11b, 802.11e standards, _802.11g, 802.11h, 802: 11i, 802.11n, 802.16, 802.16d, 802.16ee and / or future versions and / or derivatives and / or Long Term Evolution (LTE) of the above standards, a Personal Area Network (PAN), a Wireless PAN (WPAN), units and / or devices that are part of of the WLAN and / or PAN and / or WPAN networks above, one-way and / or two-way radio communication systems, cell phone radio communication systems, a cell phone, a cordless phone, a Communication Systems device Personnel (PCS), a PDA device incorporating a wireless communication device, a transceiver or multiple input and multiple output (MIMO) device, a transceiver or single input and multiple output (SIMO) device, a transceiver or multiple input and output device single (MISO), a Multiple Receiver Current (MRC) transceiver or device, a transceiver or device having intelligent antenna technology or multiple antenna technology, or the like. Some embodiments of the invention can be used in conjunction with one or more types of signals and / or wireless communication systems, for example, Radio Frequency (RF), Infrared (IR), Frequency Division Multiplexing (FDM), FDM Orthogonal (OFDM), Time Division Multiplexing (TDM),

Time Division Multiple Access (TDMA), Extended TDMA (E-TDMA), General Packet Radio Service (GPRS), Extended GPRS, Code Splitter Multiple Access (CDMA), Broadband CDMA (WCDMA), CDMA 2000, Multiple Carrier Modulation (MDM), Discrete Multiple Tones (DMT), Bluetooth (RTM), ZigBee (TM), or similar. The modalities of the invention can be used in various other devices, devices, systems and / or networks.

Although the scope of the present invention is not limited to this respect, wireless communications technologies may include radio frequency (RF) and infrared. Non-limiting examples of RF wireless standards are protocols, such as, for example, Bluetooth, ΙΕΕΕ-Std 802.11a,

... ΙΕΕΕ-Std 802.11b, 1999 edition, IEEE-Std 802.11g and HomeRF. Non-limiting examples of infrared light signals are protocols, such as, for example, the Infrared Data Association (IrDA) standard.

Although the modalities of the invention are not limited in this regard, discussions using terms such as, for example, processing, computation, calculation, determination, establishment, analysis, verification, or the like, may refer to operations and / or processes of a computer, a computing platform, a computing system, or other electronic computing device, that manipulate and / or transform data represented as physical quantities (e.g., electronic) within the computer's records and / or memories in other data similarly represented as physical quantities within the computer's records and / or memories and another information storage medium that can store instructions for performing operations and / or processes.

Although the embodiments of the invention are not limited to this respect, the terms plurality and plurality as used herein can include, for example, multiples or two or more. The terms plurality or plurality can be used throughout the specification to describe two or more components, devices, elements, units, parameters or the like. For example, a plurality of stations can include two or more stations.

Although the modalities of the invention are not limited in this regard, the term multicast / broadcast as used here can include, for example, multicast communication, broadcast communication, wireless multicast communication, wired multicast communication, broadcast communication wireless, wired broadcast communication, multicast communication over the Internet or over a global communication network, broadcast communication over the Internet or over a global communication network, multicast communication using TCP / IP, broadcast communication using TCP / IP, broadcast network communication (for example, using the WWW), and / or other types communication, for example, non-broadcast communication.

Reference is now made to Figure 1, which schematically illustrates a block diagram of an illustrative wireless communication system 100 capable of using multicast / diffusion communication according to a demonstrative embodiment of the invention. System 100 can include one or more wireless communication stations, for example, stations 101, 102, 103 and 104. System 100 can include a wireless Access Point (AP) 105. Stations 101-104 may be referred to as multicast / broadcast container devices and AP 105 may be referred to as a multicast / broadcast source device.

In some modalities, stations 101-104 and AP 105 po15 can communicate using a shared access means 190, for example, through wireless communication links 191-195, respectively. In some embodiments, stations 101-104 and AP 105 may be able to communicate according to a wireless communication standard or protocol, for example, as defined by an IEEE-Std 802.11 standard,

Edition 1999 (ISO / IEC 8802-11: 1999), IEEE 802.16 standard, or similar.

According to some modalities, for example, the AP 105 can transmit data intended to be received by more than one station using multicast or broadcast. For example, AP 105 can use multicast to transmit data to a group of stations in the system

100, you can use broadcast to transmit substantially all possible listening devices in the system 100, you can use a limited broadcast mechanism based on a network segment, you can use a direct broadcast mechanism to transmit data to the host devices of the system system 100, or similar. In some modalities, multicast / diffusion can occur through a wireless interlacing network, an ad-hoc network, a Base Service Set (BSS), an Independent BSS (IBSS), an infrastructure network, or similar.

Station 101 may include, for example, processor 111, input unit 112, output unit 113,

B.

memory 114, a storage unit 115, and a modem having

a transmitter 120 and a receiver 130. Station 101 may optionally include other suitable hardware components and / or software components. In some embodiments, the components of the station 101 can be enclosed, for example, in a common housing, packaging or similar.

Processor 111 may include, for example, a

Central Processing (CPU), a Digital Signal Processor (DSP), a microprocessor, a host processor, a controller, a plurality of processors or controllers, a chip, a microchip, one or more circuits, a set of circuits, a unit logic, an Integrated Circuit (IC), an Application Specific IC (ASIC), or any other suitable multi-purpose or specific processor or controller. Processor 111 can, for example, process signals and / or data transmitted and / or received by station 101.

Input unit 112 may include, for example, a keyboard, mouse, touch panel, pen, microphone, or other suitable pointing device or input device. Output unit 113 may include, for example, a Cathode Ray tube (CRT) monitor or display unit, a Liquid Crystal Display (LCD) monitor or display unit, a screen, a monitor, a speaker or other suitable display unit or output device.

The memory unit 114 can include, for example, a Random Access Memory (RAM), a Read Only Memory (ROM), a Dynamic RAM (DRAM), a Synchronized DRAM (SDRAM), a Fast memory, a volatile memory , a non-volatile memory, a temporary storage memory, a temporary storage, a short-term memory unit, a long-term memory unit, or other suitable memory units or storage units. The storage unit 115 may include, for example, a hard disk drive, a floppy disk drive, a Compact Disk (CD) drive, a CD-ROM drive, or other storage drives.

B.

removable and non-removable storage. The unit of_B memory 114 and / or storage unit 115 can, for example, store data transmitted and / or received by station 101.

Transmitter 120 may include, for example, a transmitter of

Wireless Radio Frequency (RF) capable of transmitting RF signals wirelessly, for example, via an antenna 121. Receiver 130 may include, for example, a wireless RF receiver capable of receiving wireless RF signals, for example, via an antenna 131. In some embodiments, for example, transmitter 120 and / or receiver 130 can be implemented using a transceiver or transceiver, using modem 125, using a Network Interface Card (NIC), or one or more units capable of carrying out separate or integrated transmission functions15 are and / or reception of signals, blocks, frames, transmission sequences, packets, messages and / or wireless communication data.

Antenna 121 and / or antenna 131 may include an internal and / or external RF antenna, for example, a bipolar antenna, a monopolar antenna, an omnidirectional antenna, and an extreme power antenna, a polarized antenna. circular, a micro strip antenna, a diversity antenna, or any other type of antenna suitable for the transmission and / or reception of signals, blocks, frames, transmission sequences, packets, messages and / or wireless communication data. In some embodiments, optionally, antenna 121 and antenna 131 can be implemented using a common or single antenna, for example, a transmit / receive antenna, or using a common set of transmit / receive antennas.

In some embodiments, station 101 or one or more stations 101-104 may include, for example, a management and control unit 141 and a diagnostic unit 142. Management unit 141 can perform operations related to multicast / broadcast communication, for example, to exchange protocol messages regarding the designation of the leader, to manage diagnostic unit 142, or to perform other operations related to communication of multicast / diffusion according to some modalities of the invention. The multicast / diffusion management unit 141 and / or the diagnostic unit 142 can be optionally implemented, for example, using separate components or units, using an integrated or combined unit, using hardware components, using software components, as part of processor 111, as part of modem 125, or the like.

Diagnostic unit 142 can perform analysis operations and can generate diagnostic information to be transmitted to AP 105. Diagnostic information generated by diagnostic unit 142 of station 101 may include, but is not limited to, a received multicast / broadcast frame count, received channel energy indicator (RCPI) associated with one or more of the multicast / broadcast frames broadcast received (for example, with the multicast / broadcast frame received last or most recently), signal to noise received (RSNI) indicator associated with one or more of the received multicast / broadcast frames (for example, with the most recently received multicast / broadcast frame20) or quality indicators associated with one or more received multicast frames or with multicast / broadcast broadcast input. It should be understood that the modalities of the invention are not limited to the diagnostic information mentioned above and that the metrics can be reported by the diagnostic unit 142 to the AP 105.

According to some embodiments of the invention, one or more of the stations 101-104 can transmit diagnostic information to the AP 105, for example, periodically, at predefined time intervals, on demand, autonomously, when a predefined condition is matched in response to a trigger event, or similar.

The AP 105 may include, for example, antennas 160 and 170, a processor 162, a transmitter 164, and a receiver 166. Although the scope of the present invention is not limited in this regard, antennas 160 and 170 may be antennas omnidirectional, monopolar antennas, bipolar antennas, edge feeding antennas, circularly polarized antennas, micro strip antennas, diversity antennas, GPS antennas or similar. The two antennas may be different, for example, one may be a bipolar antenna and the other an end-feed antenna. In some embodiments, transmitter 164 can be coupled to antenna 160 and receiver 166 coupled to antenna 170. In some embodiments of this invention, transmitter 164 and receiver 166 can be coupled to a single antenna 160.

The AP 105 may additionally include a multicast / diffusion management and control unit 152 capable of performing operations performed for the management of multicast / diffusion communication, for example, to analyze the information of multicast / broadcast diffusion diagnostics, for select or reselect the leader stations to monitor incoming multicast / broadcast diagnostic information, to monitor the multicast / broadcast receipt notice frames received (or that are to be received), to enable or disable (or otherwise modify) a multicast / broadcast receipt notice scheme, or the like. The multicast / broadcast management unit 152 can be optionally implemented, for example, using separate components or units, using an integrated or combined unit, using hardware components, using software components, as part of a processor or a modem of AP 105, or similar.

In accordance with the modalities of the present invention, the AP 105 can include a diagnostic unit 154 capable of performing the analysis and characterization of a communication transmitted by the AP 105 to a plurality of stations via multicast or broadcast and to perform the analysis operations related to diagnostic information received from one or more of stations 101-104, and the like. The analysis may include determining the characterization of the traffic reliability of the sequence. For example, a broadcast may be a commercial or advertisement broadcast and it may be acceptable for most, but not all, stations to receive traffic, and one may be an emergency multicast message or network management message and may it is desirable that a maximum number of stations receive traffic.

Analysis and characterization can be performed through a variety of means including, but not limited to, a set of rules based on information technology (IT), application-level traffic designation, and an automated heuristic analysis of traffic sequences. multicast based on established standards and / or network conditions.

In accordance with the modalities of the present invention, the diagnostic unit 154 can additionally select the most suitable diagnostic metric for designating a leading station according to the type of traffic sequence transmitted by the AP 105. For example, for a multicast of a video sequence a first diagnostic metric can be selected and for a data sequence a different diagnostic metric can be selected. In some situations, it can be crucial that information is transmitted as quickly as possible so that data latency is an important measure. For other multicast, accuracy may be more important so that the frame loss rate and the S / N ratio of the signal can be relevant metrics.

According to some modalities of the invention, for a given multicast, the diagnostic unit 154 can select a leading station from all the multicast / diffusion containers according to the selected diagnostic metric based on the characterization of the multicast communication and information of diagnostics received from multicast / diffusion containers (stations 101-104).

In some embodiments, one of stations 101-104 may be designated (for example, by AP 105) to operate as a leading station (for example, a receipt acknowledgment station, a receipt acknowledgment station, a confirmation, a designated station, a selected station, a selectively designated station, an appointed station, an elected station, a representative station, a representative container station, or similar) for a multicast selected based on the metrics associated with that multicast.

In a demonstrative embodiment, for example, station 101 can be designated as the leader station, whereas stations 102104 may not be designated leader stations - for a given multicast. Leading station 101 can, for example, exchange protocol messages with ÃP 105. For example, when leading station 101 receives a multicast / broadcast frame from AP 105, leading station 101 can transmit a packet or warning message from (ACK) for the AP 105. However, station 104 can be designated as leader for the next multicast by AP 105. This may be due, in part or completely, to the fact that different sets of metrics are used for the two transmissions, some physical change in the environment between the two broadcasts, the difference in the quality of the two broadcasts, some combination of factors, or another set of factors not mentioned.

Reference is further made to figure 2, which is a schematic flowchart of a multicast method of communication according to some illustrative embodiments of the invention. This procedure, as illustrated, can be performed for each multicast or broadcast. The method operations can be implemented, for example, by system 100 in figure 1, by any and all of stations 101-104 in figure 1, by AP 105 in figure 1 and / or by other units, devices and / or systems appropriate.

As indicated in box 210, the method may include performing analysis and characterization of a communication transmitted by the AP 105 to a plurality of stations through multicast or broadcast and determining the characterization of traffic reliability of the sequence. This may, in some embodiments of the invention, include the assignment of a priority category to each type of multicast / broadcast traffic.

As indicated in box 220, the method may include determining an appropriate metric or performance metrics, based on the characterization of a particular multicast or broadcast, for example, emergency broadcasts may receive the highest priority category and the appropriate metric for such diffusions it may be the frame loss rate (FLR). Once the performance metric has been selected, an initial threshold value can be configured, for example, for emergency broadcasts, the leader can be the station with the lowest FLR and thus the FLR threshold can initially be set to 100% in a way that all responding stations have a better - lesser FLR. In cases where the selected performance metric should be maximized, the initial value for the limit can be set to the lowest possible value so that all stations that respond have a better, or higher, value.

Subsequently, an initial leader can be selected by choosing the station initially having the lowest FLR. Note that if the FLR is used, the value that each station - any and all 101104 stations in this mode - actually reports to the AP 105 may be the frame count. The AP 105 can determine the frame count FLR since the AP 105 knows how many frames are broadcast.

In some embodiments of the invention and for some metrics, it may be desirable to configure a hysteresis condition (text box 220). Otherwise, since some metrics can change very quickly, the designated leader can vary constantly. Thus, instead of setting the current performance limit used to designate the leader as the leader's previous performance, it can be beneficial to adjust the limit upward by a certain percentage - from the leader's previous metric, for example: if the metric is one to be maximized, the threshold can be set to 20% higher than the leader's previously measured performance, and if the metric is minimized, the threshold can be set to 10% lower than the leader's previous performance leader.

According to other embodiments of the invention, the limit can simply be set equal to the current performance of the current leader, or the limit can be a fixed value determined by the type of multicast / broadcast or a requirement associated with multicast / broadcast.

As indicated in box 230, the method can optionally include, for example, the AP 105 receiving multicast / broadcast diagnostic information generated by stations 101-104 or other multicast / broadcast containers and calculation of a selected performance metric based on in the information received, for each reporting station. Diagnostic information may include, for example, the received multicast / broadcast frame count, the received signal strength indicator, the packet error rate, the signal to noise ratio, the measured latency, the measured oscillation, or other information and may or may not be limited to the metrics used in determining the performance metric chosen for multicast / broadcast.

AP 105 can calculate or estimate a different performance metric or set of performance metrics for each type of multicast and broadcast; for example, an FLR associated with a station, an average FLR per station, a signal to average received noise ratio (SNR) per station, an average signal strength received per station (RSSI), an average latency per station, an oscillation average per season, or similar, and / or any combination of metrics mentioned and any other types of metrics that may be considered useful for the particular types of transmissions.

According to the modalities of the present invention, the method may include, for example, designating as a leader of the best performing station associated with the best performing metric. The AP 105 can then periodically analyze the diagnostic information received from station 101-104 and based on the comparison between the performance metrics of the stations and the leader using the chosen hysteresis value can decide whether a new leader designation is required. If the performance of the leader starts to drop significantly, as predefined by a specific amount or percentage, some modalities of the invention may start a new leader selection circuit, as described in boxes 240-260.

As indicated by the diamond type block 240, if the selected performance metric is one to be maximized, the AP 105 can verify that the performance metric of an unassigned station, for example, station 103, is greater than the metrics of performance of the leader and that the condition of hysteresis was not met. If so, then station 103 is designated as the new leader by AP 105 (box 250). If not, then the current leading station, station 101 can remain the leader (box 260).

Likewise, if the selected performance metric is one to be minimized, the AP 105 can verify that the performance metric of an unassigned station, for example, station 103, is less than the leader's performance metrics and that the hysteresis condition has been met. If so, then station 103 is designated as the new leader by AP 105 (box 250). If not, then the current leading station, station 101 can remain the leader (box 260).

In accordance with the modalities of the invention, whenever the decision is made to designate a leader and a potential leader has been identified, the management and control unit 152 of the AP 105 can transmit a request for designation of a multicast and broadcast leader to management and control unit 141 of station 101. In response, management unit 141 can transmit the response to the multicast and broadcast leader designation to management unit 152 of AP 105. The diagnostics unit 152 of the AP 105 can transmit a request for multicast and broadcast diagnostics information to the diagnostics unit 142 of station 101. In response, the diagnostics unit 142 of station 101 can transmit the diagnostics information report for station 101. multicast and diffusion (or other appropriate response) for the diagnostic unit 154 of the AP 105.

In some embodiments, optionally, the communication between the AP 105 and / or station 101 (for example, ACK packet or message, leader assignment request, response to the leader assignment request, or similar) may use a send (RTS), a clean send (CTS) mechanism, an RTS / CTS mechanism, or other suitable protocol mechanisms.

In some embodiments, the leader station 101 can transmit a notification to the AP 105 - at any time during multicast and / or broadcasts - to indicate that the leader station 101 is about to disconnect (for example, leaving, hanging up or otherwise leave or leave) a wireless network common to the AP 105 and leader station 101, or that the AP 105 has already disconnected from such a wireless network. In response, the AP 105 can designate another station as a leader for the rest of the multicast, for example, based on diagnostic information received from one or more of the 102-104 stations that remain on the wireless network.

In some embodiments, a leader-based multicast / broadcast acknowledgment scheme can, for example, increase the reliability of multicast / broadcast communication, increase the total performance of the network, increase the total performance of the network. Some modalities may, for example, provide a link level reliability indicator for a multicast / broadcast communication source. The modalities of the invention may allow for additional benefits or advantages.

Some embodiments of the invention can be implemented by software, by hardware, or by any combination of software and / or hardware suitable for specific applications or according to specific design requirements. The modalities of the invention can include units and / or subunits that can be separated from one another or combined, in whole or in part, and can be implemented using specific, multipurpose or general processors, controllers or devices that are known in the art. technical. Some embodiments of the invention may include storage units, registers, batteries, storage units and / or memory units, for temporary or long-term storage of data or in order to facilitate the operation of a specific modality.

Some embodiments of the invention can be implemented, for example, using a machine-readable medium or article that can store an instruction or set of instructions that, if executed by a machine, for example, by system 100 in figure 1, by station 101 of figure 1, by the processor 111 of figure 1 or by other suitable machines, cause the machine to carry out a method and / or operations according to the modalities of the invention. Such a machine may include, for example, any suitable processing platform, _? computing, computing device, processing device, computing system, processing system, computer, processor or the like, and can be implemented using any suitable combination of hardware and / or software. The machine-readable medium for the article may include, for example, any suitable type of memory unit (for example, memory unit 114 or storage unit 115), memory device, memory article, memory medium, storage device , storage item, storage medium and / or storage unit, for example, memory, removable or non-removable media, erasable or non-erasable media, media that can be written or rewritten, digital or analog media, hard disk, floppy disk, Compact Disc Read Only Memory (CD-ROM), Writable Compact Disc (CD-R), Rewritable Compact Disc (CD-RW), optical disc, magnetic media, various types of Versatile Digital Discs (DVDs), tape, cassette tape, or the like. Instructions can include any suitable type of code, for example, source code, compiled code, interpreted code, executable code, static code, dynamic code, or the like and can be implemented using any high-level, low-level programming language. level, object-oriented, visual, compiled and / or interpreted, for example, C, C ++, Java, BASIC, Pascal, Fortran, COBOL, assembly language, machine code, or similar.

Other operations or sets of operations can be used according to the modalities of the invention.

While certain features of the invention have been illustrated and described here, many modifications, substitutions, changes, and equivalences can occur to those skilled in the art. It is, therefore, understood that the appended claims must cover all said modifications and changes that are within the true spirit of the invention.