Abstract: A method, a computer program product and a device, the method is for evaluating a state of a radio access network (RAN), and may include parsing control plane massages that are exchanged between the RAN and a core network that is coupled to the RAN; and determining, by an edge bandwidth manager, a current state of the RAN based on the control plane massages.

Abstract: A processor executes the following processes. An obtainment process obtains a first number of lines, which represents a number of lines that are deleted after changing, among lines that pass through the same line route. An extraction process extracts a line for which a first demand, which is accommodated before and after changing, does not exist. The extraction process further extracts lines in descending order of a band of the first demand from among lines including first demands until a total number of extracted lines reaches the first number of lines when the number of the extracted lines is smaller than the first number of lines. Then, a fixation process fixes a first demand accommodated in a line that has not been extracted. A deletion process deletes the extracted lines. A determination process determines an order of changing line routes of demands.

Abstract: A method and associated systems for using a software-defined network (SDN) controller to automatically test cloud performance. A bandwidth measuring and optimizing system associated with the SDN controller detects a triggering condition and, in response, directs a network-management tool to measure a bandwidth of a segment of a physical infrastructure of a network and directs the SDN controller to provision a virtual machine that then measures a bandwidth of a corresponding segment of virtual infrastructure that is overlaid upon the physical segment. In some embodiments, these two tests are synchronized so as to concurrently measure physical and virtual bandwidths while the same test data passes through the virtual infrastructure segment. The measured bandwidth of the virtual segment is then compared to the measured bandwidth of the physical segment in order to determine an efficiency of the virtual network.

Abstract: A method and associated systems for using a software-defined network (SDN) controller to automatically test cloud performance. A bandwidth measuring and optimizing system associated with the SDN controller detects a triggering condition and, in response, directs a network-management tool to measure a bandwidth of a segment of a physical infrastructure of a network and directs the SDN controller to provision a virtual machine that then measures a bandwidth of a corresponding segment of virtual infrastructure that is overlaid upon the physical segment. In some embodiments, these two tests are synchronized so as to concurrently measure physical and virtual bandwidths while the same test data passes through the virtual infrastructure segment. The measured bandwidth of the virtual segment is then compared to the measured bandwidth of the physical segment in order to determine an efficiency of the virtual network.

Abstract: One embodiment of the present invention provides a switch. The switch comprises one or more ports, a link management module and a load balancing module. The link management module operates a port of the one or more ports of the switch in conjunction with a remote switch to form a virtual link aggregation. The load balancing module generates an index of a weight distribution vector based on address information of a multicast group associated with the virtual link aggregation. A slot of the weight distribution vector corresponds to a respective switch participating in the virtual link aggregation. In response to the index indicating a slot corresponding to the switch, the load balancing module designates the switch as primary switch for the multicast group, which is responsible for forwarding multicast data of the multicast group via the virtual link aggregation.

Abstract: A non-transitory computer readable medium storing instructions which, when executed by one or more hardware processors, causes performance of operations including: determining a location associated with a client device, assigning a priority to packets, received from the client device or targeted for the client device, based at least on the location associated with the client device, and processing packets based on the priority assigned to the packets.

Abstract: A method, an apparatus, and a computer program product for data communication are provided. The method may include providing a plurality of data channels on a communications link, determining unused bandwidth as a difference between total bandwidth provided by the communications link and bandwidth used by the plurality of data channels, allocating the unused bandwidth to a virtual channel, scheduling the plurality of data channels and the virtual channel in accordance with a time-based multiplexing scheme, and disabling interface circuitry used to couple the transmitter to the communications link when the virtual channel is scheduled. Each of the plurality of data channels may be assigned to a source of data to be transmitted on the communications link.

Abstract: Systems and methods for predictive cache replacement policies are provided. In particular, some embodiments dynamically capture and predict access patterns of data to determine which data should be evicted from the cache. A novel tree data structure can be dynamically built that allows for immediate use in the identification of developing patterns and the eviction determination. In some cases, the data can be dynamically organized into histograms, strings, and other representations allowing traditional analysis techniques to be applied. Data organized into histogram-like structures can also be converted into strings allowing for well-known string pattern recognition analysis. The pattern recognition and prediction techniques disclosed also have applications outside of caching.

Abstract: A device and method in which plurality of Zadoff-Chu sequences is allocated to a frame, a value of a parameter in the Zadoff-Chu sequence is different among the plurality of Zadoff-Chu sequences, and the Zadoff-Chu sequence allocated to the frame is different among a plurality of cells.

Abstract: A wireless networking system is disclosed. The wireless networking system includes an application layer associated with one or more applications having a wireless bandwidth requirement. A first wireless transceiver resource associated with an actual MAC layer and PHY layer is employed. The first wireless transceiver resource has a first bandwidth availability up to a first actual bandwidth. A second wireless transceiver resource associated with the actual MAC layer and the PHY layer is employed. The second wireless transceiver resource has a second bandwidth availability up to a second actual bandwidth. A processing layer evaluates the wireless bandwidth requirement and the first and second bandwidth availabilities of the wireless transceiver resources. The processing layer includes a bandwidth allocator to allocate at least a portion of each of the first and second actual bandwidths to virtual MAC and virtual PHY layers, and to satisfy the application layer wireless bandwidth requirement.

Abstract: A method and an apparatus for managing one or more physical network interface cards and a physical host are provided. One or more virtual network interface cards are created, where each of the virtual network interface cards has a standard network interface card feature and an operation interface; the one or more virtual network interface cards are separately associated with one or more function modules of the physical network interface cards; and the physical network interface cards are managed by managing the one or more virtual network interface cards. In this way, differences in underlying hardware are shielded for an upper layer, and convenient and efficient centralized management are provided, thereby further improving network resource utilization.

Abstract: Provided are a method of allocating a resource in a wireless communication system and an apparatus using the method. The method includes: measuring a variation of a data usage pattern or density of user equipments located in a region for providing a service; determining whether the variation is greater than or equal to a threshold; and determining a resource allocation type of the region for providing the service on the basis of the determination result.

Abstract: A method of predictively provisioning cloud resources based on human behaviors and heuristics includes monitoring a collection of events relating to a customer application as well as monitoring an infrastructure load on resources for the customer application. A causal relationship is evaluated between an event and the infrastructure load. A predictive rule is then constructed based on the causal relationship. Resource requirements are anticipated based on the predictive rule and a provisioning of resources in a service domain is requested for the anticipated resource requirements.

Abstract: An antenna apparatus includes N (2=<N) transmitting antennas configured to transmit RF signals having Orbital Angular Momentum (OAM) of designated modes, and N receiving antennas configured to make N pairs with the N transmitting antennas, respectively, and to receive the RF signals having OAM of the designated modes transmitted from the corresponding N transmitting antennas within the N pairs.

Abstract: A system includes a network interface, at least one processing device, and at least one memory device. The at least one memory device stores instructions that when executed result in initiating creation of a single-use targeted link that provides access to a restricted access data entry system and serves the single-use targeted link through the network interface to a computer system of a targeted user with a time validity constraint. An access request received at the restricted access data entry system through the single-use targeted link is verified as being received within the time validity constraint. A network traffic throttling control reduces network traffic volume received through the single-use targeted link based on determining that the network traffic volume exceeds a traffic volume threshold. An identity control at the restricted access data entry system is applied to confirm entry of at least one identifying characteristic that matches the targeted user.

Abstract: A transmission apparatus includes: a data signal processor to add first data of a control signal to a data signal received, and transmit the data signal; a first signal output module to output second data of the control signal; an update controller to control an update of a function included in the first signal output module; and a second signal output module, when receiving a notice of an instruction for updating the function from the update controller, to output the first data that is the second data held therein when the notice thereof is received, wherein the second signal output module, when receiving a notice of a completion for updating the function from the update controller, outputs the first data that is the second data received from the first signal output module updated by the update controller.

Abstract: Techniques are described for tunneling high definition multimedia interface (HDMI) data over a wireless connection from an HDMI-capable source device to a client device that is physically connected to an HDMI-capable sink device via an HDMI connector. The techniques enable wireless transmission of HDMI data without video compression by using an encapsulation scheme that maps HDMI audio and video channels into a transport stream format and maps HDMI side channels into an IP datagram for transmission over the wireless connection. The source device may operate as an HDMI controller and perform HDMI-based data, control, and security processing required for HDMI connectivity with the sink device via the client device. The client device, therefore, may be a “dummy” client device that does not perform HDMI-based processing, but acts as a wireless HDMI bridge to pass the HDMI data between the source device and the sink device.

Abstract: An optical transmitter converts a plurality of transmission signals transmitted via a plurality of lanes into a multi-carrier signal and transmits the multi-carrier signal. The optical transmitter includes: a controller configured to generate allocation information that indicates an allocation of sub-carriers to the plurality of lanes according to a bit rate of the transmission signal of each of the lanes and a possible transmission capacity of each of the sub-carriers; and a signal processor configured to convert the plurality of transmission signals into the multi-carrier signal in accordance with the allocation information generated by the controller.

Abstract: Determining an initial number of TCP connections, dynamically determining increases and decreases in the number of TCP connections, and so on depending on a wireless communication method that is used enables a plurality of TCP connections to be used for wireless communication methods having higher communication bandwidths, and can thus improve communication speeds. Meanwhile, a drop in communication speed can be suppressed when using wireless communication methods having lower communication bandwidths.

Abstract: Disclosed herein are methods and systems for emulating testing-plan channel conditions in wireless networks. One embodiment takes the form of a process that includes identifying a data-rate threshold and one or more testing-plan channel conditions. The process also includes identifying testing-scenario channel conditions corresponding to the testing-plan channel conditions. The process also includes selecting an attenuation offset based on a comparison of the one or more identified testing-scenario channel conditions to the one or more identified testing-plan channel conditions. The process also includes measuring a data rate with a testing-scenario attenuation level set equal to the selected attenuation offset. The process also includes storing testing-plan-compliance data associated with the measured data rate and the data-rate threshold.

Abstract: A method for extending life of a storage system, wherein a storage controller determines a source solid-state disk (SSD) in a disk group with a capacity usage ratio greater than an average capacity usage ratio of the disk group. The capacity usage ratio of the source SSD is a ratio of a used capacity of the source SSD to an available capacity of the source SSD. The storage controller selects at least one destination SSD in the disk group with a capacity usage ratio less than the average capacity usage ratio of the disk group. And then the storage controller calculates an amount of data to be migrated from the source SSD, based on the capacity usage ratio of the source SSD and the average capacity usage ratio. At last, the storage controller migrates the data to be migrated from the source SSD to the one or more destination SSDs.

Abstract: A technique allows stations to utilize an equal share of resources (e.g., airtime or throughput). This prevents slow stations from consuming too many resources (e.g., using up too much air time). Fairness is ensured by selective dropping after a multicast packet is converted to unicast. This prevents slow stations from using more than their share of buffer resources. Multicast conversion aware back-pressure into the network layer can be used to prevent unnecessary dropping of packets after multicast to unicast (1:n) conversion by considering duplicated transmit buffers. This technique helps achieve airtime/resource fairness among stations.

Abstract: A method is provided for sending an acknowledgement frame by a receiving entity. The method includes: subsequent to reception of a data frame sent by a sending entity and including a synchronization field containing an invariant item of information known to the entities and an identification field containing information identifying the sending entity and the receiving entity, sending an acknowledgment frame including a synchronization field; and calculating a signature of a transmission channel between the sending entity and the receiving entity, the synchronization field of the acknowledgment frame being obtained on the basis of the synchronization field of the data frame, by using the signature.

Abstract: Systems, methods, and devices for wireless communication are provided. In an embodiment, a method of determining communication parameters for wireless communication includes receiving, at an access point, a probe request comprising a transmission power indication. The method further includes determining a received transmission power. The method further includes estimating a path-loss based on the transmission power indication and received transmission power. The method further includes transmitting a first probe response using a first set of communication parameters defining a first rate. The method further includes transmitting a second probe response using a second set of communication parameters defining a second rate when the access point does not receive an acknowledgement to the first probe response within a timeout period, the second rate being lower than the first rate.

Abstract: The invention relates to a method for allocating a common radio resource for simultaneous transmission of data streams in multiple pairs of communication nodes in a multi-node wireless network. The invention also relates to a method of assessing radio resource isolation in a multi-node wireless network. The inventive methods include transmission (44) of at least a first and a second test probe message on a common radio test resource. Receipt of the intended test probe messages are verified (45), whereupon radio resource isolation may be determined and a common radio resource allocated (46) for transmission in the tested communication node pairs. The invention also relates to a communication node and a control node wherein the inventive methods are applied.

Abstract: A device may establish a communication session, with a client device, for monitoring a latency of a service. The device may receive, from the client device, a request for a monitored service list. The monitored service list may identify one or more services for which service latency monitoring is supported. The device may provide, to the client device, the monitored service list. The device may receive, from the client device, a service latency monitoring session request that may identify the service to be monitored. The device may establish, with the client device, the service latency monitoring session based on the service latency monitoring session request. The device may cause the service to be performed. The device may generate information for determining the latency of the service. The device may transmit, to the client device and via the service latency monitoring session, the information for determining the latency of the service.

Abstract: Techniques are provided for bifurcating database information that might otherwise be replicated on each switch in a switched fabric of a Storage Area Network (SAN). The database is divided into a control plane database that comprises mostly switch specific data and a central management database that comprises user device configurations and device profiles. The control plane database includes information such as name server and zone server information, for those devices that may locally log into the switched fabric via a given switch, and those remote devices that are zoned with those local devices and that may log into the switched fabric via another switch. The central management database includes global information for the switched fabric and device profile information (e.g., login interface, Virtual SAN membership, device aliasing, etc.) for devices that have access to the switched fabric and that can also be requested by the various switches in the switched fabric.

Abstract: A computing device for low-latency multimedia using dual wireless adapters, comprising a first wireless adapter connected to a Wi-Fi access point; a second wireless adapter connected directly to a plurality of wireless devices; and an operating system comprising programming instructions stored in the memory and operating on the processor and configured to: receive streaming multimedia via a wireless network from a media source, using the first wireless network adapter; and send at least a subset of the streaming multimedia at least one of the plurality of wireless devices using the second wireless network adapter.

Abstract: A method for watching high-definition cable TV programs includes: a blue-tooth learning remote controller learning remote-controller controlling instructions of a high-definition cable TV set top box, and uploading the learned instructions to a smart terminal such that the smart terminal controls the high-definition cable TV set top box; the smart terminal controlling the high-definition cable TV set top box to choose high-definition cable TV programs; the high-definition cable TV set top box outputting a HDMI signal; the smart TV dongle receiving the HDMI signal, and outputting the HDMI signal to a high-definition TV; the smart TV dongle performing an encoding and a packing on the HDMI signal and then transmitting the packed signal to the smart terminal by using a wireless manner; and the smart terminal performing a de-packing and a decoding on the received signal and then playing the decoded signal on the smart terminal.

Abstract: Methods, systems, and computer programs for measuring quality of multimedia delivery to a client are presented. A method includes operations for embedding video markers in a video stream of a multimedia stream, and embedding audio markers in an audio stream of the multimedia stream. The video stream and the audio stream are then transmitted separately to the client. Further, video markers received at the client are extracted from the transmitted video stream, and audio markers received at the client are extracted from the transmitted audio stream. A measure of the audio-video synchronization quality is obtained by determining a quantifiable time difference between the video stream and the audio stream received at the client, where the quantifiable time difference is calculated based on the extracted video markers and the extracted audio markers.

Abstract: A communication node disposed on a packet transfer path through which packets flow between an end of a transmitting side and an end of a receiving side according to a specific protocol under which flow control and congestion control using a window size are performed, the communication node including a communication interface configured to perform processing for receiving a packet from a link on the transfer path and processing for transmitting a packet to the link, a storage device configured to store a queue in which a packet in accordance with the specific protocol received from the link or a packet in accordance with the specific protocol transmitted to the link is temporarily accumulated, and a controller configured to adjust a period of time for retaining the packet accumulated in the queue on the basis of the current bandwidth of the link on the receiving side.

Abstract: A system is provided that can include one or more devices to: identify an event that has a predefined start time and end time, determine that a particular amount of bandwidth is needed for the event, and generate a notification that identifies the particular amount of bandwidth and the predefined start time and end time for the event, where the particular amount of bandwidth is reserved on a channel for the predefined start time and end time, for the event, in response to the notification.

Abstract: Scalable codecs are used for transmitting channel zapping data for one or more programs using timeslicing. The main codec layer may be utilized also for the zapping data, and the higher layers may be used in the primary channels. Zapping data may be provided to mobile terminals via a wireless multicast network, such as a DVB-H network, using timeslicing and providing the scalably encoded zapping data as part of the source stream.

Abstract: Packets from a first network entity to a second network entity are received. A maximal size of packets from the second network entity to the first network entity is determined based on information in the received packets.

Abstract: The present invention is related to a method for routing requests among a plurality of database servers. A device intermediary to a client and a plurality of database servers receives a request to access a database provided by the plurality of database servers. The plurality of database servers can include a first database server configured to process write requests and one or more second database servers configured to process read requests. The device determines that the request to access the database is a read request. The device identifies, responsive to determining that the request is a read request, one of the one or more second database servers to send the request instead of the first database server. The device then transmits the request to the identified second database server.

Abstract: Embodiments of the present invention relate to audiovisual stream processing in videoconferences. For each audiovisual stream in a videoconference, a sound level of the audiovisual stream is detected. If the sound level exceeds a predefined threshold level, the audiovisual stream is processed with a first configuration. If the sound level is below the predefined threshold level, the audiovisual stream is processed with a second configuration. The second configuration is more resource-effective than the first configuration.

Abstract: A method that incorporates teachings of the present disclosure may include receiving, by a system comprising a processor, a request from a mobile communication device to configure a computing environment for executing a software application, identifying a deficiency in an availability of a resource of the computing environment responsive to receiving the request, adjusting an operation of the computing environment to change the availability of the resource responsive to identifying the resource deficiency, and providing an action of a plurality of associable actions to the computer environment for use in the software application, where the action replaces a received stimulation of a user input that is associated with the executing of the software application. Other embodiments are disclosed.

Abstract: A multi-radio device system includes a set of sending radio devices and a set of receiving radio devices. Among the sending radio devices is a load-balancing radio device that receives data packets from an originating network. The load-balancing radio device labels data packets with sequence numbers and distributes the labeled data packets among the sending radio devices based on the relative capacities and statuses of those sending radio devices. The sending radio devices transmit the labeled data packets to the receiving radio devices. The receiving radio devices send the labeled data packets to an aggregating radio device within the set of receiving radio devices. The aggregating radio device uses the sequence numbers to ensure that the data packets are forwarded to a destination network in the correct order, extracting original data packets from the labeled data packets before forwarding the original data packets on toward the destination network.

Abstract: A method of managing bandwidth usage among a plurality of client devices is provided. A request is received at a first device from a second device. The request is to transfer a file between the first device and the second device and includes an identifier of the second device. A client group associated with the second device is determined based on the identifier and used to select a bandwidth usage policy. A data transfer rate for transferring the file between the first device and the second device is determined based on the selected bandwidth usage policy and a bandwidth usage at the first device associated with a plurality of devices. A number of bytes to transfer is determined based on the determined data transfer rate and a time period. A response, which includes the determined number of bytes and the time period, is sent to the second device.

Abstract: In a media delivery system over an Internet Protocol (IP) network, a device for network jitter reduction and rate reconstruction using a means for receiving streams with jitter, buffering the streams, and playing out/streaming each stream at an original rate of respective streams.

Abstract: A communication method executed by a processor included in a relay device, the communication method includes receiving a target packet among a plurality of segmented packets generated by dividing a transmission packet, the plurality of segmented packets including a same identifier as that of the transmission packet; storing the target packet into a memory, when no error is detected from the target packet; discarding one or more packets stored in the memory and including a same identifier as that of the target packet, when an error is detected from the target packet; generating a discard request including an identifier of the transmission packet, and information requesting to discard a packet including the identifier, when the discarded one or more packets do not include a head packet among the plurality of segmented packets; and transmitting the discard request to a transmission destination to which the head packet is transmitted.

Abstract: Techniques for dynamic backhaul bandwidth provisioning are described herein. For example, a method may include determining a potential subscriber user equipment load change, transmitting a backhaul bandwidth change request message based a potential subscriber UE load change, wherein the backhaul bandwidth change request message includes a requested backhaul bandwidth level, receiving a backhaul bandwidth change reply message in response to transmitting the backhaul bandwidth change request message, implementing a subscriber UE load change response corresponding to the potential subscriber UE load change based on receiving the backhaul bandwidth change reply message.

Abstract: An apparatus and method for communication including determining an assignment for one of a plurality of symbol durations in a format combination; determining if at least one bit from one or more first upper channels is available if the assignment is associated with the one or more first upper channels and occupying the one of the plurality of symbol durations with the at least one bit, or if unavailable, occupying the one of the plurality of symbol durations with at least one bit from one or more second upper channels or another first upper channel, wherein the first upper channels and the second upper channels are different; and disabling transmission of format information; or including enabling a BTFD hypothesis testing mode; receiving one or more symbol durations on a physical channel; and attempting to decode the received symbol duration with a first hypothesis that a DCCH channel is not transmitted.

Abstract: The disclosure relates to conveying state changes from an advertising node to one or more discovering nodes, wherein the advertising node may convey the state changes using small efficient low-level broadcast or multicast advertisements to trigger delivering larger structured data in a manner that may be conceptually similar to broadcasting or multicasting but actually delivered using point-to-point or other delivery mechanisms that may be more efficient and reliable. In particular, the advertising node may the convey state changes using connectionless messaging and a store-and-forward cache in a manner that removes bandwidth and/or size constraints that networks impose on multicast/broadcast datagrams while preserving benefits associated therewith.

Abstract: A method of managing bandwidth allocation across a video pipe that delivers both streaming adaptive bitrate (ABR) content and progressive download ABR content includes receiving a designation of a congestion boundary within a video pipe, the congestion boundary designating a first percentage of the video pipe that is to be used for streaming ABR content when congestion exists on both sides of the congestion boundary, wherein a remaining percentage of the video pipe is to be used for progressive download ABR; allocating bandwidth for streaming ABR content, wherein the gateway device can allocate for streaming content only that portion of the remaining percentage of bandwidth that is not requested for progressive download content; and allocating bandwidth for progressive download content, wherein the gateway device can allocate for progressive download content only that portion of the first percentage of bandwidth that is not requested for streaming content.

Abstract: Techniques for supporting variable channel bandwidths in a wireless communications network are described. In one embodiment, for example, an apparatus may comprise a processor circuit and a communications management module, and the communications management module may be operable by the processor circuit to determine a channel bandwidth for communication over a channel of a wireless network, transmit a beamforming initiation message comprising a channel bandwidth parameter indicating the determined channel bandwidth, receive a beamforming initiation confirmation message confirming the channel bandwidth parameter, perform a beamforming training sequence to determine one or more beamforming parameters, and transmit one or more messages over the channel according to the determined channel bandwidth and the one or more beamforming parameters. Other embodiments are described and claimed.

Abstract: Example methods, apparatuses, and/or articles of manufacture are disclosed that may be implemented, in whole or in part, using one or more computing devices to implement a queuing system with an adjustable scalability/reliability level.

Abstract: A traffic adjustment method and an apparatus, which relate to the communications field, so that statistics on traffic of a receiving apparatus that needs to receive a first multicast packet can be accurately collected in a process of multicast packet transmission. A specific solution is as follows: A sending apparatus sends a first multicast packet, and determines whether an identity of a first receiving apparatus is in a receiving list of a first group, and if the identity of the first receiving apparatus is in the receiving list of the first group, the sending apparatus acquires multicast traffic of the first receiving apparatus, and subtracts the multicast traffic of the first receiving apparatus from preset traffic allocated to the first receiving apparatus to obtain corrected traffic of the first receiving apparatus.

Abstract: A mesh network, operating as a virtual Ethernet switch, includes multiple nodes operating as Mesh Network Gateway Interfaces (mesh NGIs) enabled for communication with one or more shared access networks. Selectively coupling the multiple NGIs to the same shared access network provides redundancy and load balancing aimed at improving the reliability and performance of the network. A first architecture is based on a gateway group, including a plurality of NGIs enabled to communicate with a single shared access network via a designated broadcast server elected from among the NGIs. A second architecture is based on a plurality of (physical) NGIs enabled to communicate with a single shared access network via one or more designated nodes in the shared access network. The designated nodes, or Mesh Servers (MSs), operate as virtual NGIs, and traffic entering or exiting the mesh flows through one of the MSs, thus improving packet broadcast efficiency.

Abstract: Codec selection and usage for calls includes identifying a call scheduled for a time in the future from an electronic calendar associated with a user and prior to the call, ordering a plurality of codecs used by an Internet Protocol (IP) phone of the user for the scheduled call. During the call and using a processor, a mean opinion score for the call is calculated and stored as part of call data for the call within a data storage device including historical call data.