Abstract: Methods, apparatus, and systems for a beam failure recovery on one or more secondary cells are described. In one example aspect, a wireless communication method includes receiving, by a first device, parameters configured to carry out beam failure detection and beam failure recovery for secondary cells associated with the first device, determining, by the first device, whether a beam failure event has occurred on at least one of the secondary cells based on at least one of the parameters, performing, upon a determination that the beam failure event has occurred, a beam failure recovery procedure for the secondary cell with the beam failure event, and terminating the beam failure recovery procedure upon an occurrence of a termination event.

Abstract: Backup communication paths can be determined for use by different circuits of a network in the event of a failure of active communication paths. The disclosed backup path determination techniques can reduce contention in which multiple circuits share a backup path. Contention metrics are determined for communication paths in the network. The contention metrics are used to determine a communication path for contention reduction. A circuit that uses the communication path as a backup path is selected, and the backup path of the selected circuit is modified to avoid the communication path. Contention metrics can then be recalculated, and contention reduction techniques can be repeated until a desired convergence point is reached.

Abstract: Systems, methods, and computer-readable media are provided for performing secure frame encryption as a service. For instance, a network edge device can determine at least a first path and a second path for routing a data packet. The network edge device can obtain a first plurality of values for at least one network metric, wherein the first plurality of values corresponds to the first path and at least a first backup path associated with the first path. The network edge device can obtain a second plurality of values for the at least one network metric, wherein the second plurality of values corresponds to the second path and at least a second backup path associated with the second path. The network edge device can select one of the first path or the second path for routing the data packet based on a comparison of the first plurality of values and the second plurality of values.

Abstract: Systems and methods for performing a Control Plane Triggered (CPT) Optical Protection Switching (OPS) policy are provided. A method, according to one implementation, includes performing a first route switching procedure for switching routes between an originating node and a terminating node. The first route switching procedure is configured to operate at a first priority level according to an Optical Protection Switching (OPS) policy. The method also includes performing a second route switching procedure for switching routes between the originating node and the terminating node. The second route switching procedure is configured to operate at a second priority level according to a second protection policy, wherein the second priority level is higher than the first priority level. Also, the method includes reverting back to a home path according to the first route switching procedure after one or more faults, defects, or degradations have been cleared from the home path.

Abstract: Provided is a method for determining and performing a packet duplication transmission between wireless devices. The method comprises receiving, from an evolved NodeB (eNB), configuration information associated a packet duplication transmission between wireless devices, wherein the configuration information comprising a packet reliability parameter associated with activation of the packet duplication transmission between wireless devices; determining, by a first wireless device, a data packet to be transmitted to a second wireless device; duplicating, based on determining the data packet satisfies the packet reliability parameter, the data packet to a plurality of data duplicates; mapping the plurality of data duplicates onto different logical channels in a media access channel (MAC) layer; and transmitting, by the first wireless device and via a direct communication to a second wireless device, the plurality of data duplicates mapped onto different logical channels.

Abstract: Some embodiments provide a method for implementing a logical router that spans multiple datacenters. The method receives a configuration for a set of logical switches and a logical router (LR) that (i) handles data traffic between data compute nodes (DCNs) connected to the logical switches and endpoints not connected to the set of logical switches and (ii) performs stateful services on the traffic. The DCNs include at least one DCN operating in each datacenter. For each datacenter, the method defines a centralized routing component (SR) for the LR for handling the traffic between the DCNs in the datacenter and the endpoints not connected to the set of logical switches. The method designates one of the SRs as a primary SR and the other SRs as secondary SRs. The secondary SRs forward traffic, received from DCNs in their respective datacenters and for which stateful services are required, to the primary SR.

Abstract: Examples disclosed herein relate to tracking a usage metric for each of a plurality of communication assets, determining whether the usage metric fails to meet a threshold for each of the plurality of communication assets, and in response to determining that the usage metric fails to meet the threshold for at least one of the plurality of communication assets, causing the at least one of the plurality of communication assets to be disabled.

Abstract: In general, techniques are described for signaling IP path tunnels for traffic engineering using constraints in an IP network. For example, network devices, e.g., routers, of an IP network may compute an IP path using constraint information and establish the IP path using, for example, Resource Reservation Protocol, to signal the IP path without using MPLS. As one example, the egress router generates a path reservation signaling message that includes an egress IP address that is assigned for use by the routers on the IP path to send traffic of the data flow by encapsulating the traffic with the egress IP address and forwarding toward the egress router. As each router in the IP path receives the path reservation signaling message, the router configures a forwarding state to forward traffic encapsulated with the egress IP address to a next hop along the IP path toward the egress router.

Abstract: When a failure occurs in a counterpart company network, the cause of the failure is specified. A failure detection apparatus 1 that detects a failure in a counterpart company network includes a hierarchy level detection unit 11 detecting the number of hierarchy levels indicating a depth of hierarchy levels of the counterpart company network by transmitting a request including the maximum number of transfers to the counterpart company network, a failure location specifying unit 13 specifying a hierarchy level of a failure location in the counterpart company network by transmitting the request to the counterpart company network in a case where the failure in the counterpart company network has been detected, and a determination unit 14 determining that the failure is present in a network core apparatus of the counterpart company network in a case where the hierarchy level of the failure location is a hierarchy level at a depth less than the number of hierarchy levels of the counterpart company network.

Abstract: Systems and methods include receiving a request for a service in a Segment Routing network; determining an intended path for the service, provisioning a head-end node with a Segment Identifier (SID) list for the intended path, and reserving bandwidth for the service on the intended path; monitoring the Segment Routing network; and responsive to a condition determined based on the monitoring, updating the SID list for the service. The condition can include a current path for the service in the Segment Routing network differing from a provisioned path in the Segment Routing network. The condition can be based on any of a failure in the Segment Routing network, a topology change in the Segment Routing network, bandwidth changes in the Segment Routing network, an optimization timer, and input from an operator.

Abstract: Systems and methods for a Border Gateway Protocol (BGP) route aggregation exception include advertising, to BGP peers, of a plurality of prefixes using BGP route aggregation or summarization; detecting a failure that is local to the router affecting a prefix of the plurality of prefixes; and advertising an aggregation exception that identifies the prefix to all of the BGP peers. The systems and methods can also include detecting recovery of the failure; and sending a withdrawal of the aggregation exception to all of the BGP peers.

Abstract: A safety detector including a detection module configured for reading a control signal at the input, the detector including two supply terminals, a first control input and a first control output, a first safety output and a second safety output, and a first free terminal and a second free terminal, the detector including: a second control input connected to the first free terminal and a second control output connected to the second free terminal, and a test module configured for notably applying a first test sequence including a disabling of the first control output and a test of a start loop connected between the second control output and the first control input.

Abstract: The present disclosure is directed to BIER forwarding over varying BSL domains, the methods including the steps of receiving, at a border node, a packet comprising a BIER header having a BIER bit string with a first bit string length; reading an incoming label of the packet comprising instructions to split the BIER header into a plurality of smaller headers associated with a plurality of smaller bit strings; generating a set of split bit masks; performing a separate bitwise AND operation on each split bit mask and the BIER bit string to generate the plurality of smaller bit strings, each copied to a corresponding smaller header of the plurality of smaller headers; and performing a lookup for each of the plurality of smaller headers on a respective forwarding table to determine one or more egress routers to which to transmit the packet.

Abstract: A system that includes a first edge node and a second edge node in signal communication with one or more interior nodes. The first edge node is configured to receive a correlithm object from a first device outside of the network, to identify an input correlithm object from the first node table with the shortest distance, to fetch a corresponding correlithm object from the first node table, and to send the correlithm object to the one or more interior nodes. The second edge node is configured to receive a correlithm object from the one or more interior nodes, to identify an input correlithm object from a second node table with the shortest distance, to fetch a corresponding correlithm object from the second node table, and to send the correlithm object to a second device outside of the network.

Abstract: Disclosed is a first device and a second device each sending BFD echo request packets in an initial stage of establishing communication between the two devices. A method can include determining that a certain mode is detected, such as a low bandwidth mode. The method can be practiced by one or both of the devices or a separate network controller. Based on the detection of the certain mode or the communication link being in a certain mode, the method includes the first device or the second device electing to be a master or a slave. Upon establishing that one of the devices is the master and the other of the devices is a slave, only the master will send BFD echo request packets.

Abstract: Provided are a resource requesting method and device, and a resource request processing method and device. The method includes: acquiring, by a terminal, a buffer size corresponding to an same frequency point or anchor frequency point in a logical channel group; reporting, by the terminal, an Sidelink BSR to a base station, where the Sidelink BSR includes at least one of: a destination index corresponding to the same frequency point or anchor frequency point; a logical channel group identifier or a logical channel identifier; or a buffer size.

Abstract: Various systems and methods for performing fast fail-over. One method involves receiving a packet at a primary forwarder node of a core network, determining whether the packet was received from a secondary forwarder node of the core network, via a tunnel, and, in response to a determination that the packet was received via the tunnel, forwarding the packet to another node in the core network. The tunnel communicatively couples the primary forwarder node and the secondary forwarder node. The primary forwarder node and the secondary forwarder node communicatively couple a local network and the core network. The packet was transmitted from the local network.

Abstract: Broadband communications devices and methods operate with at least two separate communication paths between the devices and the network, such as the Internet. The broadband devices and methods receive data concurrently over the communication paths or separately. The bandwidth is increased when the separate communication paths are combined. The broadband devices employ packetized data with Voice over Internet Protocol (VoIP) technologies combined with RF communications technologies.

Abstract: A multicast traffic transmission method includes: detecting (S201) whether a transmission link between a designed forwarder (DF) and a traffic reception device is abnormal; and when the transmission link between the DF and the traffic reception device is abnormal, sending (S202) a first request to a backup designed forwarder (BDF). A packet of the first request includes a protection mark and address information about the traffic reception device, and the first request is used for requesting the BDF to forward traffic to the traffic reception device.

Abstract: A fabric connection assist system includes a networking device coupled to a fabric management system and a mobile device via a network. The networking device receives fabric connection information for its port from the fabric management system. When the mobile device subsequently identifies that port to the networking device, the networking device identifies fabric connection components to the mobile device that are indicated by the fabric connection information as being supported by its port. When the mobile device subsequently identifies a first of the fabric connection components to the networking device, and the networking device then detects that the first fabric connection component has been connected to its port, the networking device transmits a first fabric connection component confirmation communication to the mobile device that is configured to display a confirmation on the mobile device of the connection of the first fabric connection component to its port.

Abstract: In accordance with one or more embodiments described herein, a method is provided. The method includes receiving a request to assume control of a vehicle generated by a candidate operator via a first communication pathway. The method obtains a key from an onboard controller of the vehicle and communicates the key to the candidate operator via a second communication pathway that is different from the first communication pathway. The method determines the candidate operator to be a confirmed operator based at least in part on obtaining the key from the candidate operator via the first communication pathway.

Abstract: The stability and reliability of broadband service connectivity improved by utilizing both wireline and wireless connections. For example, a residential gateway may continue to provide stable broadband connectivity to a service provider network (e.g., exceeding minimum quality of service thresholds) when subjected to a broadband fault (e.g., loss or degradation of data) by managing or utilizing both a wireline broadband connection and a wireless broadband connection.

Abstract: A data connection recovery system is disclosed that includes a data connection management platform configured to monitor a status of a data connection of a wireless communication device with a wireless network. In response to a determination that the data connection is nonfunctional, the data connection management platform is configured to initiate a command to the wireless communication device via a control plane of the wireless network commanding the wireless communication device to switch to a different network slice in a user plane of the wireless network. The system also includes a remote device manager on the wireless communication device configured to receive the command and to initiate establishment of a new data connection with the wireless network via the different network slice in response to the command. The wireless communication device transmits data via the new data connection.

Abstract: The disclosed embodiments provide a system for managing a stream-processing application. During operation, the system allocates a first host for an active instance of the stream-processing application that maintains a state during processing of one or more input streams. Next, the system allocates a second host for a first backup instance that recreates the state on the active instance by consuming changes to the state replicated from the active instance without consuming the input stream(s). During a failure on the first host, the system moves the active instance to the first host by stopping the first backup instance on the second host. Finally, the system launches the active instance on the second host to resume processing of the input stream(s) by the active instance using the recreated state from the first backup instance.

Abstract: Source routing techniques include sending data across several networks, while limiting source routing overhead. For example, the source routing techniques may use a first address format to route data to nodes along a routing path that are within a first network where a source node is located, and use a second address format to route the data to a node along the routing path that is within a second, different network. The node in the second network may similarly route the data through the second network using the first address format for nodes within the second network and, if needed, route the data to a node within a third network using the second address format. This may be repeated for any number of networks to reach a destination.

Abstract: Methods for performing neighbor state management between peers of a Multi-Chassis Link Aggregation Group (MCLAG) are provided. In one method, a first peer of a Multi-Chassis Link Aggregation Group (MCLAG) performs state management for each neighbor entry in a first set of neighbor entries. Similarly, a second peer of the MCLAG connected in parallel with the first peer performs state management for each neighbor entry in a second set of neighbor entries, the second set of neighbor entries containing contain at least one neighbor entry absent from the first set of neighbor entries.

Abstract: A method implemented by a network element (NE) in a network, comprising receiving, by the NE, an advertisement comprising preferred path route (PPR) information and backup PPR information, the PPR information describing a PPR between a source and a destination in the network, the backup PPR information describing a backup PPR between the source and the destination, the PPR information comprising a PPR identifier (PPR-ID) and a plurality of PPR description elements (PPR-PDEs) each representing an element on the PPR, updating, by the NE, a local forwarding database to include the PPR information and the backup PPR information in association with a destination address of the destination, and transmitting, by the NE, a data packet based on the backup PPR information instead of the PPR information in response to an element on the PPR being unavailable due to a failure of an element along the PPR.

Abstract: In an example method, network traffic transmitted between a plurality of network nodes via a communications network is monitored. Subsets of the network traffic are ranked according to one or more ranking criteria. A mesh network is deployed between the plurality of network nodes based on the ranking of the subsets of the network traffic. The mesh network includes a plurality of network links, where each network link communicatively couples a respective network node from among the plurality of network nodes to another respective network node from among the plurality of network nodes.

Abstract: A method for configuring a fabric managed by a software-defined networking (SDN) controller includes, with a first control host installed in a first rack having a first management switch and a second control host installed in a second rack, executing controller nodes that implement an SDN controller using a controller virtual network extending between the first rack and the second rack. The first management switch is configured to route traffic between the controller virtual network and a device management network extending from the first management switch to a fabric network device of the fabric managed by the SDN controller. The method further includes configuring, with the SDN controller, via the first management switch, the fabric network device with the controller virtual network to enable communications, via the controller virtual network, between the first control host and a compute node or a storage node connected to the fabric network device.

Abstract: A tactical solution to network congestion is provided by a data forwarding device having (1) a first interface with a first link to a downstream data forwarding device and (2) second interface with a second link to a downstream data forwarding device, and executing a method comprising: (a) configuring the second interface as part of a loop-free alternate (LFA) path to a destination device, wherein the first interface is part of a shortest/preferred path to the destination device; (b) monitoring congestion at the first interface to determine whether or not the congestion exceeds a first threshold; and (c) responsive to a determination that the congestion exceeds the first threshold, forwarding at least some data addressed to the destination device, over the LFA path via the second interface instead of over the shortest/preferred path via the first interface, thereby alleviating congestion at the first interface, and otherwise, responsive to a determination that the congestion does not exceed the first threshol

Abstract: A method includes receiving, by a network device, notification packets separately sent by a plurality of forwarding nodes, where each notification packet includes interface forwarding delay information of the forwarding node that sends the notification packet, device forwarding delay information of the forwarding node, and a transmission delay of a link connected to the forwarding node; obtaining the interface forwarding delay information and the device forwarding delay information of each of the plurality of forwarding nodes, and obtaining a transmission delay of a link between the plurality of forwarding nodes; and computing a forwarding path between a first forwarding node and a second forwarding node, where a forwarding delay of the forwarding path meets a delay requirement of a service.

Abstract: Disclosed in the present application are an information transfer method and device. When a user side node sends a traffic request through a MLD, IGMP or PIM protocol or sends prefix information through routing protocols such as Babel, BGP, OSPF, ISIS and the like, a forwarding side node can clearly know by a manner of adding a user side mark whether the user side node is connected to the forwarding node. When performing forwarding according to a BIER rule, the forwarding side node can identify the user side node and encapsulate a packet to have a correct destination address to be sent, so as to ensure that the user side node can correctly receive a traffic message.

Abstract: The present disclosure relates to forwarding of network traffic. In one of its aspects, the technology presented herein concerns a method for forwarding network traffic from multiple sources to multiple destinations on maximally disjoint paths by maximally redundant trees, MRTs. The method is implemented in a network element implementing multipoint-to-multipoint functionalities in a path computation element, PCE, of a network, wherein the network includes a plurality of network elements. According to the method, an almost directed acyclic graph, ADAG, is computed for the network. Next hops along MRTs are computed by using the ADAG. One or more valid path pair(s) of the computed MRTs that is/are disjoint is/are determined and then, the network traffic is forwarded by using the valid path pair(s) of the MRT(s).

Abstract: The disclosure relates to a mobile device configured to receive from a network a notification of a predicted change of a Quality-of-Service, QoS related to a local end-to-end data communication path; and configured to provide a report to the network, the report comprising at least one of the following information: location information, application layer information, mobile device status information, experienced QoS at mobile device side, radio channel conditions. The disclosure further relates to a network device configured to transceive communication data via a communication path, in particular a local end-to-end data communication path between a mobile device and another mobile device, based on a Quality-of-Service, QoS, requirement for the communication path; and configured to notify the mobile device about a predicted change of the QoS related to the communication path.

Abstract: For use in a system including a first data forwarding device, a second data forwarding device, a third data forwarding device, a first communications link between the first data forwarding device and the second data forwarding device, and a second communications link between the first data forwarding device and the third data forwarding device, the first and second communications links belonging to a link aggregation group (LAG), a method includes (1) generating a message (i) for testing a first path between the first data forwarding device and the second data forwarding device, and a second path between the first data forwarding device and the third data forwarding device, and (ii) including an Internet protocol (IP) datagram including a multicast IP destination address and a payload containing path testing information; and (2) sending, over the LAG, the message from the first data forwarding device to both the second data forwarding device and the third data forwarding device.

Abstract: Systems and methods for managing edge routers include monitoring one or more trigger conditions related to transport links between two or more edge routers and one or more external networks. A first parameter associated with a first edge router is modified if at least one trigger condition is detected, the at least one trigger condition related to at least one transport link between the first edge router and the one or more external networks. The first parameter is compared with a second parameter associated with a second edge router of the two or more edge routers. A role of primary edge router is dynamically reassigned to one of the first edge router or the second router based on the comparison of the first parameter and the second parameter, where traffic between a local network and the one or more external networks is routed through the primary edge router.

Abstract: There is provided a method comprising, at a user equipment operating in connection with a first radio access technology network and a second radio access technology network, determining that communication using the second radio access technology is to be suspended and in response to the determining, suspending communication using the second radio access technology and storing a configuration relating to the second radio access technology such that communication using the second radio access technology can be reactivated via at least one of the first radio access technology network and the second radio access technology network.

Abstract: A system to facilitate resolving traffic congestion in a network switching fabric is described. The system includes a processor and a machine readable medium storing instructions that, when executed, cause the processor to receive a notification from a virtual connect switch indicating that a congestion condition has been detected in remote direct memory access (RDMA) over Converged Ethernet (RoCE) data traffic flowing from a first end point to a second end point via a first of a plurality of paths between the first end point and the second end point, identify a second of the plurality of paths between the first end point and the second end point and modify the RoCE data traffic to flow from the first end point to the second end point via the second path.

Abstract: In an example method for redundant multicast trees with fast recovery, a protocol independent multicast (PIM) backup designated router (BDR) can receive a request from a host to join a multicast group associated with a source; send to a next hop a PIM join message identifying an address of the PIM BDR and identifying the PIM join message as a backup PIM join; receive, from a PIM router along a path to/from the source, a unicast message sent to the address which identifies a second address associated with the PIM router; store the second address and a route associated with the unicast message; in response to a designated router migration trigger, set to blocking a backup multicast tree state associated with the source and multicast group; and send, to the PIM router, a unicast message including instructions to set to blocking a backup multicast tree state at the PIM router.

Abstract: Embodiments including methods, systems, and apparatuses for distributing, processing, and reacting to path information distributed via a service-agnostic packet fabric for the purpose of enabling path selection are disclosed. By configuring two ingress line cards to send path quality words to each other via the switch fabric, compare the path quality words, and determine whether to transmit traffic to an egress line card via the switch fabric based on the comparison of the path quality words, the embodiments enable a central switch fabric to be unaware of the paths that it carries, and enable both ingress and egress bandwidth of the switch fabric to be sized according to the facilities for which it is terminating. The switch fabric does not need to support working and protection paths simultaneously in some embodiments, allowing it to be scaled appropriately to termination facilities.

Abstract: A method and an apparatus for reselecting Tx carrier for sidelink transmission in wireless communication system is provided. The method, by a UE, may include selecting a first carrier upon which the wireless device performs first sidelink transmission based on the first carrier to a target wireless device, detecting a number of retransmissions unacknowledged on the first carrier, and performing second sidelink transmission to the target wireless device based on a second carrier different from the first carrier.

Abstract: In a method, a controller sends a first route update packet including a first route to a first forwarding device, so that the first forwarding device sends a third route update packet including a third route to at least one target forwarding device; a second forwarding device receives the third route update packet, determines a target link from the first forwarding device to the second forwarding device, and sends, based on a monitored state of the target link, a second route update packet including a second route and a target field to the controller; and the controller determines the state of the target link based on the target field in the second route update packet.

Abstract: Apparatuses and methods comprise receiving traffic from multiple virtual machines (VMs) associated with a same identification (ID); mapping the ID into a destination Internet Protocol (IP) address; and forwarding the traffic from the multiple VMs to a first gateway instance announcing the destination IP address.

Abstract: A wireless communication method includes receiving, by a standby policy and charging control (PCC) function device, an authentication authorization request (AAR) message from an application function (AF), and obtaining, from a standby subscription profile repository based on an internet protocol (IP) address carried in the AAR message, the IP-connectivity access network (CAN) session information corresponding to the AAR message.

Abstract: In one embodiment, a method comprises receiving traffic to send from a router to a host in the fabric edge network, wherein the fabric edge network comprises a plurality of switches and an inter-switch link (ISL); and sending the traffic from the router to the host via at least one of the switches based on the downlink connectivity of the host. Sending the traffic from the router to the host is performed without sending the traffic through the ISL. Sending the traffic from the router to the host comprises sending the traffic through the ISL when there is a link failure on a path between the router and the host.

Abstract: A method of operating a mesh network is disclosed (FIG. 6). The method includes receiving a data frame (600) having a header with plural addresses (FIG. 1) and determining that the data frame is not from an access point or a leaf node (602) of the mesh network. A next recipient address of the plural addresses is removed (610) when the next recipient is a final destination. The next recipient address is set (612) when the next recipient of the data frame is not a final destination. The data frame is transmitted (614) to the next recipient.

Abstract: Embodiments of the present disclosure provide methods and devices for data transmission by a switch. The method can include transmitting, by the switch, over a first path, a first packet that is received from a first host to a second host; receiving a replacement packet from the first host, wherein the replacement packet is transmitted from the first host in response to a determination that the first packet was lost and wherein the replacement packet includes a path indicator; and based on the path indicator of the replacement packet, transmitting, over a second path different from the first path, at least part of the replacement packet to the second host.

Abstract: Provided are a method and an apparatus for generating a forwarding entry and a machine-readable storage medium, which are applied to a distributed resilient network interconnect (DR) network comprising a remote device and a DR device. The remote device is connected with the DR device. The DR device includes first DR member device and at least one second DR member device, each of which is connected with a host via an aggregation port. In an example of the method, when receiving first synchronous message carrying address information of the host from the first DR member device and the first synchronous message carries an identifier of the aggregation port, the remote device determines that the remote device connects the DR device via at least two tunnels of the aggregation port according to the identifier, and generates a forwarding entry corresponding to the host according to information of each of the tunnels.

Abstract: The disclosure relates to a data forwarding method and a node device for a mesh network. The mesh network comprises a plurality of nodes. At least one of the plurality of nodes is a relay node which forwards a data packet from a source node to a destination node. The method includes determining whether or not to forward the data packet in accordance with a type and a forwarding count value of the data package. The forwarding count value is changed in different manners in accordance with the type of the data packet when the data packet is forwarded. The data forwarding method decreases forwarding times of the data packets, reduces power consumption and increases efficiency of network communication.

Abstract: A method for configuring access by a user to fallback communication services, includes sending by an application client an authentication request to an identity management server; and in the event of rejection: the identity management server allocates a fallback identifier and sends the fallback identifier to the application client; the application client sends a request for fallback user profile to a configuration management server; the application client sends a request for fallback multimedia group profiles to a multimedia group management server; the application client sends a request for fallback multimedia group encryption keys and private communications encryption keys to an encryption keys management server; once the application client has received the fallback user profile, the fallback multimedia group profile(s), the fallback multimedia group encryption key(s) and the private communications encryption key(s), the user can access the fallback communication services.