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US6741575B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus and method for efficient delivery of multicast data over personal access communications system (PACS)

Assignee: The AT&T MVPD Group LLC
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Filing: 1999-02-26
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Granted: 2004-05-25
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Expires: 2019-02-26
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Abstract

Abstract A method, apparatus, article of manufacture, and a memory structure for multicasting data in a cellular personal access communication system is disclosed. The method comprises the steps of allocating a multicast packet terminal identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group, receiving a multicast packet having a global multicast address, determining a cell identifier from a mapping of the global multicast address to at least one local multicast identifier and a cell identifier, and forwarding the multicast packet to the cell according to the cell identifier. The apparatus comprises a radio port controller unit having a packet data control unit coupled to a radio port configured to receive a multicast packet and a packet forwarding module. The packet data control unit includes an allocation module configured to allocate a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group. The packet forwarding module is configured to determine a cell identifier from a mapping of the global multicast address to at least one local packet terminal identifier and a cell identifier and to forward the multicast packet to a cell according to the cell identifier.

Inventors

  • 👤 Yongguang Zhang
  • 👤 Bo Ryu
  • 👤 Son K. Dao
  • 👤 Tayyab Khan
  • 👤 Stanley E. Kay
  • 👤 Sivakamar Kailas

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 22:54
CPC Classifications
H; H04; H04L; H04L61/00; H04L12/00; H04L12/02; H04L12/16; H04L12/18; H04L12/189; H04L61/50

Claims Analysis

Total Claims: 42
Claim 1
Independent Claim 76 words
A method of multicasting data, comprising the steps of: allocating a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group; receiving a multicast packet having a global multicast address; determining a cell identifier from a mapping of the global multicast address to at least one local multicast identifier and a cell identifier; and forwarding the multicast packet to a cell according to the cell identifier.
Claim 2
Independent Claim 76 words
A method of multicasting data, comprising the steps of: allocating a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group; receiving a multicast packet having a global multicast address; determining a cell identifier from a mapping of the global multicast address to at least one local multicast identifier and a cell identifier; and forwarding the multicast packet to a cell according to the cell identifier.
Claim 3
Dependent Claim 87 words
The method of claim 1 , wherein the global multicast address, the multicast local packet identifier, the cell identifier and a subscriber unit internet protocol (IP) address associated with the subscriber unit are stored in a table, and the method step of determining the cell identifier from the mapping of the global multicast address to at least one local multicast identifier and a cell identifier comprises the step of searching the table for multicast local packet identifier, and the cell identifier associated with the global multicast address.
Claim 4
Dependent Claim 129 words
The method of claim 1 , wherein the step of allocating a local multicast identifier to a multicast group when a subscriber unit requests membership in a multicast group comprises the steps of: receiving a registration request from the subscriber unit associated with a subscriber unit internet protocol (IP) address; determining if the multicast group exists; assigning a local multicast identifier to the multicast group and storing a mapping between the global multicast address, the cell identifier, the local multicast identifier, and the subscriber unit IP address if the multicast group does not exist; retrieving the local multicast identifier for the multicast group and adding the subscriber unit IP address to the mapping if the multicast group does exist; and transmitting the local multicast identifier to the subscriber unit.
Claim 5
Dependent Claim 44 words
The method of claim 3 , wherein the registration request includes a global multicast address, and a terminal ID uniquely identifying the subscriber unit, and the method further comprises the step of authenticating the registration request and responding with the subscriber unit IP address.
Claim 6
Dependent Claim 43 words
The method of claim 3 , wherein the step of allocating a local multicast identifier to a multicast group when a subscriber unit requests membership in a multicast group further comprises the step of storing the local multicast identifier in the subscriber unit.
Claim 7
Dependent Claim 33 words
The method of claim 1 , wherein the step of allocating the local multicast identifier comprises the step of selecting the local multicast identifier from a group of reserved local packet terminal identifiers.
Claim 8
Dependent Claim 32 words
The method of claim 1 , wherein the step of allocating the local multicast identifier comprises the step of selecting the local multicast identifier from a group of local packet terminal identifiers.
Claim 9
Dependent Claim 32 words
The method of claim 1 , wherein a local multicast identifier allocated to a second multicast group is allocated to the multicast group if all available local multicast identifiers are currently allocated.
Claim 10
Dependent Claim 29 words
The method of claim 1 , further comprising the steps of: intercepting a membership query from an internet router; and replying to the membership query based on the mapping.
Claim 11
Dependent Claim 70 words
The method of claim 1 , further comprising the steps of: accepting a de-registration message from the subscriber unit; determining if the subscriber unit is an only member of the multicast group; deleting the subscriber unit from the multicast group if the subscriber unit is not the only member of the multicast group; and deleting the multicast group if the subscriber unit is the only member of the multicast group.
Claim 12
Dependent Claim 106 words
The method of claim 10 , wherein the global multicast address, the local multicast identifier, the cell identifier and the subscriber unit IP address is stored as a row in a table, and wherein: the step of deleting the subscriber unit from the multicast group if the subscriber unit is not the only member of the multicast group comprises the step of deleting the subscriber unit IP address from the table; and the step of deleting the multicast group if the subscriber unit is the only member of the multicast group comprises the step of deleting the multicast group and all associated entries from the table.
Claim 13
Dependent Claim 51 words
The method of claim 1 , further comprising the step of: determining if the subscriber unit has transmitted a message to the cell within a time period; and deleting the subscriber unit from the mapping if the subscriber unit has not transmitted a message to the cell within a time period.
Claim 14
Independent Claim 82 words
An apparatus for multicasting data, comprising: means for allocating a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group; means for receiving a multicast packet having a global multicast address; and means for determining a cell identifier from a mapping of the global multicast address to at least one local multicast identifier and a cell identifier; and means for forwarding the multicast packet to a cell according to the cell identifier.
Claim 15
Independent Claim 82 words
An apparatus for multicasting data, comprising: means for allocating a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group; means for receiving a multicast packet having a global multicast address; and means for determining a cell identifier from a mapping of the global multicast address to at least one local multicast identifier and a cell identifier; and means for forwarding the multicast packet to a cell according to the cell identifier.
Claim 16
Dependent Claim 139 words
The apparatus of claim 13 , wherein the means for allocating a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group comprises: means for receiving a registration request from the subscriber unit associated with a subscriber unit internet protocol (IP) address; means for determining if the multicast group exists; means for assigning a local multicast identifier to the multicast group and storing a mapping between the global multicast address, the cell identifier, the local multicast identifier, and the subscriber unit IP address if the multicast group does not exist; means for retrieving the local multicast identifier for the multicast group and adding the subscriber unit IP address to the mapping if the multicast group does exist; and means for transmitting the local multicast identifier to the subscriber unit.
Claim 17
Dependent Claim 30 words
The apparatus of claim 13 , further comprising: means for intercepting a membership query from an internet router; and means for replying to the membership query based on the mapping.
Claim 18
Dependent Claim 75 words
The apparatus of claim 13 , further comprising: means for accepting a de-registration message from the subscriber unit; means for determining if the subscriber unit is an only member of the multicast group; means for deleting the subscriber unit from the multicast group if the subscriber unit is not the only member of the multicast group; and means for deleting the multicast group if the subscriber unit is the only member of the multicast group.
Claim 19
Dependent Claim 52 words
The apparatus of claim 13 , further comprising: means for determining if the subscriber unit has transmitted a message to the cell within a time period; and means for deleting the subscriber unit from the mapping if the subscriber unit has not transmitted a message to the cell within a time period.
Claim 20
Dependent Claim 116 words
A radio port controller unit for multicasting data, comprising: a packet data control unit coupled to a radio port configured to receive a multicast packet, the packet-data control unit having an allocation module configured to allocate a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group; and a packet forwarding module, coupled to the packet data control unit, the packet forwarding module configured to determine a cell identifier from a mapping of a global multicast address for the multicast packet to at least one local multicast identifier and a cell identifier and to forward the multicast packet to a cell according to the cell identifier.
Claim 21
Dependent Claim 116 words
A radio port controller unit for multicasting data, comprising: a packet data control unit coupled to a radio port configured to receive a multicast packet, the packet-data control unit having an allocation module configured to allocate a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group; and a packet forwarding module, coupled to the packet data control unit, the packet forwarding module configured to determine a cell identifier from a mapping of a global multicast address for the multicast packet to at least one local multicast identifier and a cell identifier and to forward the multicast packet to a cell according to the cell identifier.
Claim 22
Dependent Claim 24 words
The apparatus of claim 18 , wherein the global multicast address, the local multicast identifier, and the cell identifier are stored in a table.
Claim 23
Dependent Claim 33 words
The apparatus of claim 19 , wherein the radio port further comprises a registration module configured to receive a registration request from the subscriber unit having a subscriber unit internet protocol (IP) address.
Claim 24
Dependent Claim 87 words
The apparatus of claim 20 , wherein the packet forwarding module further comprises: a group verification module configured to query the table to determine if the multicast group exists; and an assignment module configured to assign the local multicast identifier to the multicast group, to store the mapping between the global multicast address, the cell identifier, and the local multicast identifier, and the subscriber unit IP address if the multicast group does not exist and to receive the multicast local packet terminal if the multicast group exists.
Claim 25
Dependent Claim 42 words
The apparatus of claim 18 , wherein the radio port controller unit further comprises an internet group membership protocol service module, configured to intercept a membership query from an internet router and to reply to the membership query according to the mapping.
Claim 26
Dependent Claim 77 words
The apparatus of claim 18 , wherein: the radio port is further configured to receive a de-registration message from the subscriber unit; and the radio port controller unit further comprises a de-registration module configured accept the de-registration message, to delete the subscriber unit from the multicast group if the subscriber is not the only member of a multicast group, and to delete the multicast group if the subscriber unit is the only member of the multicast group.
Claim 27
Dependent Claim 41 words
The apparatus of claim 18 , wherein the radio port controller unit further comprises a handoff module configured to delete the subscriber unit IP address if the subscriber unit has not transmitted a message to the cell within a time period.
Claim 28
Independent Claim 55 words
A method of multicasting data, comprising the steps of: determining a cell identifier from a mapping of a global multicast address of a received multicast packet to at least one local multicast identifier allocated to a multicast group and a cell identifier; and forwarding the multicast packet to a cell according to the cell identifier.
Claim 29
Independent Claim 55 words
A method of multicasting data, comprising the steps of: determining a cell identifier from a mapping of a global multicast address of a received multicast packet to at least one local multicast identifier allocated to a multicast group and a cell identifier; and forwarding the multicast packet to a cell according to the cell identifier.
Claim 30
Dependent Claim 28 words
The method of claim 25 , wherein: the method further comprises the step of receiving the multicast packet, and wherein the multipath packet comprises a global multicast address.
Claim 31
Dependent Claim 20 words
The method of claim 26 , further comprising the step of: allocating the multicast terminal identifier to the multicast group.
Claim 32
Independent Claim 63 words
A method for forwarding a multicast packet to at least one cell of a plurality of cells, comprising: determining the at least one desired cell from a mapping of a global multicast address to at least one multicast local paket terminal identifier and a cell identifier; and forwarding the multicast packet to the at least one desired cell according to the cell identifier.
Claim 33
Independent Claim 63 words
A method for forwarding a multicast packet to at least one cell of a plurality of cells, comprising: determining the at least one desired cell from a mapping of a global multicast address to at least one multicast local paket terminal identifier and a cell identifier; and forwarding the multicast packet to the at least one desired cell according to the cell identifier.
Claim 34
Dependent Claim 29 words
The method of claim 28 , wherein each one of the plurality of cells manages groups and addresses associated therewith independently from other cells of the plurality of cells.
Claim 35
Dependent Claim 39 words
The method of claim 29 , wherein the mapping of the global multicast address is performed by dynamically mapping the global multicast address to a vector of group addresses each corresponding to one cell of the plurality of cells.
Claim 36
Independent Claim 61 words
An apparatus for forwarding multicast data packets to a desired cell, comprising: a multicast data packet forwarding module configured to determine a cell from a mapping of a global multicast address for the multicast packet to at least one local multicast identifier and a cell identifier and to forward the multicast packet to the desired cell according to the cell identifier.
Claim 37
Independent Claim 61 words
An apparatus for forwarding multicast data packets to a desired cell, comprising: a multicast data packet forwarding module configured to determine a cell from a mapping of a global multicast address for the multicast packet to at least one local multicast identifier and a cell identifier and to forward the multicast packet to the desired cell according to the cell identifier.
Claim 38
Dependent Claim 24 words
The apparatus of claim 31 , wherein the global multicast address, the local multicast identifier, and the cell identifier are stored in a table.
Claim 39
Dependent Claim 104 words
A radio port controller unit for multicasting data, comprising: a packet data control unit coupled to a radio port configured to receive a multicast packet, the packet data control unit having an allocation module configured to allocate a local multicast identifier to a multicast group; and a packet forwarding module, coupled to the packet data control unit, the packet forwarding module configured to determine a cell identifier from a mapping of a global multicast address for the multicast packet to at least one local multicast identifier and a cell identifier and to forward the multicast packet to a cell according to the cell identifier.
Claim 40
Dependent Claim 104 words
A radio port controller unit for multicasting data, comprising: a packet data control unit coupled to a radio port configured to receive a multicast packet, the packet data control unit having an allocation module configured to allocate a local multicast identifier to a multicast group; and a packet forwarding module, coupled to the packet data control unit, the packet forwarding module configured to determine a cell identifier from a mapping of a global multicast address for the multicast packet to at least one local multicast identifier and a cell identifier and to forward the multicast packet to a cell according to the cell identifier.
Claim 41
Dependent Claim 99 words
A radio port controller unit for multicasting data, comprising: a packet data control unit coupled to a radio port configured to receive a multicast packet, the packet data control unit having an allocation module configured to allocate a local multicast identifier to a multicast group; and a packet forwarding module, coupled to the packet data control unit, the packet forwarding module configured to identify a cell from a mapping of a global multicast address for the multicast packet to at least one identified local multicast and the indentified cell and to forward the multicast packet to the indentified cell.
Claim 42
Dependent Claim 99 words
A radio port controller unit for multicasting data, comprising: a packet data control unit coupled to a radio port configured to receive a multicast packet, the packet data control unit having an allocation module configured to allocate a local multicast identifier to a multicast group; and a packet forwarding module, coupled to the packet data control unit, the packet forwarding module configured to identify a cell from a mapping of a global multicast address for the multicast packet to at least one identified local multicast and the indentified cell and to forward the multicast packet to the indentified cell.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2007-05-25 2007-11-24 2008-05-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2011-05-25 2011-11-24 2012-05-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2015-05-25 2015-11-24 2016-05-25 $7700.00 Window Closed / Lapsed

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