967 results about "Multicast message" patented technology

The invention relates to a system and method for efficiently distributing multicast messages within computer networks configured to have one or more virtual local area network (VLAN) domains. A multicast network device (MND), having a plurality of interfaces, includes a multicast controller for efficiently distributing multicast messages among subscribing entities associated with various VLAN domains. The multicast controller, which is in communicating relationship with the interfaces, includes a VLAN assignment engine for assigning responsibility for the VLAN domains to the extent there are multiple MNDs. The multicast controller also accesses a multicast tag source to establish a plurality of novel VLAN tags for efficiently distributing multicast messages, including a sub-regional Multicast VLAN Identifier (MVLAN-ID) that encompasses all of the VLAN domains for which the respective MND is responsible, and one or more color-limited MVLAN-IDs that encompass all of the VLAN domains for which the MND is responsible except for one. The multicast controller then tags multicast messages with its sub-regional or a color-limited MVLAN-ID depending on whether the message is considered internal or external by the respective MND. The tagged messages are then forwarded for distribution to the subscribers associated with the various VLAN domains.

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.

A method and apparatus for providing multicast messages across a data communication network, the method comprising receiving a multicast message and adding to the multicast message a vector stack including at least one address of a router to which the multicast message is to be sent. The multicast message and the vector stack are then forwarded. At the first router indicated by the vector stack, the next address to which the multicast message is to be sent is read. This is repeated as necessary until the multicast message is received by the final address in the vector stack. The multicast message is then routed to the address indicated in the original multicast message.

A method of operation for a node of an Ethernet access network includes issuing a multicast message on the Ethernet access network by a maintenance end point (MEP) of the node. The multicast message contains a name of a target MEP. The node is further operable to receive a unicast reply message from the target MEP, the unicast message reply containing a MEP identifier (MEP-ID) and a MEP Media Access Control (MAC) address of the target MEP. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Systems, methods, and instrumentalities are disclosed to desynchronize transmissions in group-based operations. A group user equipment (UE), e.g., a UE that is a member of a group of UEs, may be in an inactive mode. The group UE may receive a multicast message indicating that the group UE may enter an active mode. For example, the group UE may use the active mode for periodic reporting of its monitoring activity to the network. The multicast message may indicate a mechanism for the group UE to use to send an uplink transmission to the network. The group UE may send the uplink transmission to the network at a transmission time indicated by the mechanism. The transmission time may be desynchronized from other UEs in the group.

A presence tracking architecture for datagram-based protocols. A client application seeking to know the presence or lack thereof of a device and/or service utilizes a standard protocol in a non-intuitive way to trigger notification of the device and/or service before any associated timeout expires. At first presence, a multicast message is broadcast to notify all devices. Subsequently, on-demand notification may be requested by a client application by sending directly (e.g., in unicast) to the device before its timeout has expired a message that is normally only sent in multicast. If capable, the device can then respond normally with a unicast message indicating it is on-line. If the response is not received, the device and/or service is determined to be off-line.

An access point (102) conveys (202) to communication units (104) of a plurality of multicast groups, a first indication that the access point supports a method for sending a multicast message. The access point receives (204) a multicast message directed to a receiving one of the plurality of multicast groups, and determines (206) that the communication units belonging to the receiving one of the plurality of multicast groups also support the method. The access point signals (208) a second indication to selectively awaken the communication units belonging to the receiving one of the plurality of multicast groups, and transmits (210) the multicast message to the receiving one of the plurality of multicast groups in a manner that allows (212) at least one communication unit not belonging to the receiving one of the plurality of multicast groups to remain asleep during the transmitting.

Transmission methods for multicast messages and for signaling message responses thereto in communication systems supporting a multicast mode provide that a number of retransmissions of a multicast message may be changed based on a number of receivers of the message. Signaling messages to the multicast message may be transmitted in response to a fixed number of multicast message transmissions, and receivers that have not received the multicast message after the fixed number of transmissions may request further retransmissions up to an additional given number of times. Further, signaling messages may be transmitted at different times or staggered based on a radio condition of the receivers. For example, a first multicast message may be transmitted, and responses from groups of receivers may be listened to for a given period, after which one of a next multicast message and a portion of the first multicast message may be transmitted to the groups.

The invention discloses a method for building an MAC (Media Access Control) address table and a provider edge device. In the method, a PE (Provider Edge Device) receives a first service message by a PW (Pseudo Wire) connected with the PE; when the first received service message is confirmed to be a specific-type message, the building of the address table entry of the source MAC address of the first service message is cancelled, wherein the specific-type message is an unknown unicast message, a multicast message or the broadcasting message of a non-free ARP (Address Resolution Protocol) message. According to the scheme provided by the embodiment of the invention, the amount of the address table entries built by the PE is reduced so as to reduce the volume of the MAC address table.

Methods and apparatus for maintaining Mobile IP operation in a Home Agent are disclosed. In a Home Agent, a Mobile Node is registered and a registration entry is created in a mobility binding table for the Mobile Node. A multicast message is then sent to a virtual router group to which the Home Agent belongs and with which the Home Agent shares a virtual IP address. The multicast message notifies the virtual router group of the registration. A similar process may be performed when a Mobile Node is de-registered. When an active or non-active Home Agent is initialized, it sends a multicast mobility binding table request to the redundancy group indicating that bindings are requested. The Home Agent may then receive bindings in response to the request and update its mobility binding table with the received bindings.

The invention proposes a method for transmitting a message to a plurality of user entities in a network by using a multicast service, comprising the steps of encrypting a multicast message by using ciphering, and sending the encrypted multicast message to the plurality of user entities simultaneously. The invention also proposes a corresponding multicast service control device and a corresponding user entity.

A message system for delivering data in the form messages between message clients comprises a server cluster with a group of client manager nodes and a group of independent message manager nodes. The client manager nodes have the function of managing client connections, whereas the message manager are configured to store and distribute messages. The system further comprising communication channel means in the form of a multicast messagebus for providing a multicast communication channel between said at least one client manager node and said at least one message manager node. The system guarantees delivery of a message by storing it until a receiver is ready to consume it.

A head-end in a data-over-cable system transmits a multicast message in a downstream channel to all the cable modems in a particular MAC layer. The message includes an address field that contains an upstream channel multicast MAC address that identifies a particular channel, and is used to send a multicast message for which only cable modems transmitting in the upstream direction in that channel are to respond. When the message is received by the cable modems, the cable modems compare the upstream channel multicast MAC address with addresses stored in a memory. If a match is found, indicating that the cable modem happens to transmit in the upstream direction in the particular channel, it processes the message. If no match is found, the message is discarded. The upstream channel multicast MAC address helps noise avoidance or redundancy problems associated with a particular channel to be quickly remedied, and avoids the head-end from having to send out a large number of unicast messages in order to communicate with all the modems sharing a given upstream channel.

A packet format for multicast messages which designates a single receiver to send an acknowledgment to the multicast message. The designated receiver responds to the multicast message with an acknowledgment. If the designated receiver does not respond to the multicast message, the message is resent. The resent message may designate a different receiver for acknowledging the message.

A system and method for identifying and grouping multiple virtual local area networks into a single multicast domain is provided. The system and method may be configured to designate a virtual local area network within as a multicast virtual local area network to streamline the delivery of multicast messages via a network. A station may be configured with multiple group keys so that it can receive messages from multiple broadcast or multicast domains.

A method and system for multicasting or broadcasting a message to a specific group of mobile stations or to a specific group of cell sectors in a cellular wireless communication system. The method may include maintaining a record of which mobile stations are in a particular multicast group, and may include maintaining a record of which cell sectors are currently serving one or more members of the multicast group. The records may be maintained at one or more network entities, such as a radio network multicast router/server and/or hosts on a packet-switched network. By sending multicast messages, such as IP messages, to only those cell sectors currently serving members of a multicast group, network resources may be conserved.

Example implementations are directed to more efficiently delivering a multicast message to multiple destination components from a source component. Multicast environment is achieved with transmission of a single message from a source component, which gets replicated in the NoC during routing towards the destination components indicated in the message. Example implementations further relate to an efficient way of implementing multicast in any given NoC topology, wherein one or more multicast trees in the given NoC topology are formed and one of these trees are used for routing a multicast message to its intended destination components mentioned therein.