Abstract:
The invention relates to a system and method for dynamically externalizing service delivery with a streaming system in a data transmission system. The method comprises the steps of forwarding at least one user context to an external service infrastructure partner (SIP) device when the streaming system is triggered by an event A; reconfiguring a switch layer when the at least one user context is received by the external SIP to allow user reconnection requests to be rerouted to the SIP; stopping the stream delivery for the at least one user; and restarting the stream delivery by the SIP for the at least one user upon receiving a user reconnection request.

Description:
TECHNICAL FIELD  
       [0001]     The invention relates to the use of complementary resources when application usage in a data center increases through peaks, and in particular, relates to a system and a method for dynamically delivering the streaming of audio-video using external resources.  
       BACKGROUND  
       [0002]     The primary goal of most Information Technology (IT) systems is to meet required performance and service availability levels for managed applications at the lowest possible cost and risk, while maintaining the highest customer satisfaction. In trying to achieve this goal, the management processes of traditional systems have over-provisioned their data center, particularly when the Internet network has workload levels that vary from relatively predictable to unpredictable (e.g., spiky). Such an over-provisioning includes the dedication of sufficient computing capacity to support each application during its highest potential user demand.  
         [0003]     Until now, the reality of over-provisioning has resulted in high costs accompanied with unpredictable service levels, while today&#39;s business environment is fast paced and demanding. To be successful and competitive, IT systems must meet business demands by delivering what is needed, where it is needed, and when it is needed. As such, in a dynamic and fluctuating marketplace, new on-demand processes and technologies are required. In today&#39;s economy, companies, and in a general way, IT organizations, cannot afford to maintain a server capacity for just-in-case situations, but need optimized and flexible infrastructures.  
         [0004]     Different products already exist that constantly monitor service levels, anticipate resource requirements for peak workloads, and then automatically implement the needed services. For example, IBM&#39;s Tivoli Intelligent ThinkDynamic Orchestrator can be used to create, customize, and store workflow, personalized with specific policies and procedures, to automate processes in testing and data centers. The execution of these processes can be gradually implemented in a manual, semi-automatic, and finally automatic mode. This allows a company to progress at its own evolutionary pace to become a dynamic and automated on-demand business. However, these products are currently centered on resources they own (resources that have been assigned) and more importantly do not include definitions (workflow) for audio-video service provisioning.  
         [0005]     In a data center, computing resources are finite and the business importance of each application varies. For this reason, such products as IBM&#39;s Tivoli Intelligent ThinkDynamic Orchestrator only help optimize resource allocation based on the relative importance of each application. For example, a lower priority application for streaming data including audio and/or video may be temporarily shut down while waiting for a higher priority application to be run according to its agreed service levels, until the load falls below the required threshold. As such, users using the streaming service lose their connection, and therefore there is a need for an alternate infrastructure to keep the streaming service active.  
       SUMMARY OF THE INVENTION  
       [0006]     Accordingly, an object of the invention is to provide a system and to achieve a method enabling an external streaming infrastructure to be used when the streaming servers of a data center are supporting other higher priority applications during on-demand peaks.  
         [0007]     Another object of the invention is to provide a system and to achieve a method enabling the streaming service of a service provider or a data center to be allocated for other purposes in case dedicated applications need complementary in-house resources.  
         [0008]     Another object of the invention is to provide a system and to achieve a method enabling the availability of the streaming services in a service provider or a data center to be maintained when these streaming services require a larger infrastructure to answer greater demands or when the in-house infrastructure requires maintenance or for resiliency including countering security attacks and infrastructure failures.  
         [0009]     The invention therefore relates to a method for dynamically externalizing service delivery with a streaming system in a data transmission system in which at least one user computer is connected to an Internet protocol (IP) transport network to transmit requests to and receive data from a plurality of servers through a switch layer and to receive stream delivery from at least one of the servers in charge of handling at least one user context associated with the at least one user. The method comprises the steps of forwarding the at least one user context to an external service infrastructure partner (SIP) device when the streaming system is triggered by an event A; reconfiguring the switch layer when the at least one user context is received by the external SIP to allow user reconnection requests to be rerouted to the SIP; stopping the stream delivery for the at least one user (this may include the step of forwarding timing information to delay the stopping of the stream delivery); and restarting the stream delivery by the SIP for the at least one user upon receiving a user reconnection request.  
         [0010]     According to another aspect, the invention relates to a system for dynamically externalizing service delivery with a streaming system in a data transmission system in which at least one user computer is connected to an IP transport network to transmit requests to and receive data from a plurality of servers through a switch layer and to receive stream delivery from at least one of the servers in charge of handling at least one user context associated with the at least one user. The system comprises a dynamic workload (DW) device connected to the switch layer and adapted to perform the steps of forwarding the at least one user context to an external service infrastructure partner (SIP) device when the streaming system is triggered by an event A; reconfiguring the switch layer when the at least one user context is received by the external SIP to allow user reconnection requests to be rerouted to the SIP; stopping the stream delivery for the at least one user; and restarting the stream delivery by the SIP for the at least one user upon receiving a user reconnection request. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The above and other objects, features and advantages of the invention will be better understood by reading the following more particular description of the invention in conjunction with the accompanying drawings wherein:  
         [0012]      FIG. 1  is a block diagram representing a system for dynamically externalizing the streaming traffic to a service infrastructure partner (SIP) according to the invention;  
         [0013]      FIG. 2  is a schematic diagram representing the flow of data between the dynamic workload and the other components of the system when the decision of externalizing the streaming traffic is triggered; and  
         [0014]      FIG. 3  is a schematic diagram representing the flow of data between the dynamic workload and the other components of the system when the externalizing of the streaming traffic is no longer required. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]     In reference to  FIG. 1 , it is assumed that a plurality of hosts such as host  10  can have access to audio and/or video (hereafter referred to as “audio-video”) streaming services through an IP transport network  12  by using a streaming system  14 .  
         [0016]     Hosts  10  preferably can be a personal computer or any user computer equipped with a stream player.  
         [0017]     The audio-video services or streaming are composed of two components:  
         [0018]     the portal, where users can subscribe to the service and select the audio-video they wish to access; and  
         [0019]     the pump or stream server which is responsible to send the audio (such as a song), or the video (such as a movie).  
         [0020]     The audio-video is sent to a user computer where it is handled by an audio-video player (or stream player) coupled to the user computer. The audio-video stream is stored as a file on the portal, but is streamed to the stream player which doesn&#39;t have at any point of time the full completed file. The purpose of the stream is to send packet per packet and local buffering is used to cope with possible network latency.  
         [0021]     There are two possibilities to send audio-video:  
         [0022]     the scheduling where the content is sent to several users at a specific time to minimize the usage of the bandwidth, as only one stream is used via multicast. The flow is sent to all the user computers, and the multicast technology is configured at the network level. As such, for the multicast all the routers on the road of the traffic are to be configured; and  
         [0023]     the audio-video on demand (UniCast) where the user selects the content he wants to see. In this case, there is one stream per user. The term stream or streaming will refer to audio-video all throughout this description.  
         [0024]     The streaming system  14  is composed of a set of servers  14 - 1 ,  14 - 2 ,  14 - 3 ,  14 - 4  which could be normally any kind of servers but are stream servers in the present invention. The stream servers  14 - 1 ,  14 - 2 ,  14 - 3 ,  14 - 4  are used to deliver audio-video content. The traffic exchanged through the IP transport network  12  passes through a switch layer  16  which is in charge of connecting the IP transport network  12  and the access network  20  to the streaming system  14 . It must be noted that the switch layer  16  is preferably a switch layer  3 / 4  as well known by those skilled in the art. Moreover, the streaming system  14  can be owned by a service provider or included in the data center of a company.  
         [0025]     Assuming that the traffic load can no longer be processed by the streaming system  14 , the principle of the invention is to use a service infrastructure partner (SIP)  18 , which can be external resources made available as a stream service provided by other lines of business inside the company or another company or a service provider. It is assumed that the SIP  18  is able to deliver equivalent quality of service to the original provider. This includes equivalent audio-video catalogs. The SIP  18  is connected to the switch layer  16  by means of an access network  20  which can be any kind of network such as a wide area network (WAN) or a local area network (LAN), but also a single specialized line. When the installation of re-routing has been completed as described below, a reconnection request from the host  10  is re-routed to SIP  18  by the switch layer  16  via IP transport network  12  and access network  20 .  
         [0026]     As the solution of delivering the stream by another streaming infrastructure has to be completely transparent to the users, a dynamic workload (DW) device  22  is provided. The DW device  22  is in charge of transferring to the SIP  18  all the data required for ensuring the streaming delivery as soon as it is decided to have the SIP  18  deliver the streaming service. The DW device  22  is also in charge of disconnecting the existing stream connection and reconfiguring the switch layer  16 .  
         [0027]     Note that the DW device  22  can be triggered to take the actions of service delivery in an automatic way (on the basis of technical and business rules), in a manual way (manual trigger by an operator or as a trigger of an external information such as when the priority has to be given to another service), or a mix thereof.  
         [0028]     As illustrated in  FIG. 2 , the first step of the method of service delivery according to the invention is the arrival of an event A which is, as mentioned above, a manual or automatic operation triggering the DW device  22  for taking the action of service delivery.  
         [0029]     At this stage, it is assumed that the DW device  22  has already received the user context from the streaming system  14  as illustrated in  FIG. 2 . The user context which is provided by the streaming servers preferably includes:  
         [0030]     a list of the names of the stream (audio/video) to be displayed;  
         [0031]     the IP address of the user of the user computer;  
         [0032]     the status progress of the current stream; and  
         [0033]     the service delivery quality parameters (such as the size of the video frame).  
         [0034]     When triggered, the DW device  22  forwards the user context as defined above to the SIP  18  whose availability has been checked previously. Then, the switch layer  16  is reconfigured by the DW device  22  in order to be able to send the reconnection request to the SIP  18  when the current stream is disconnected by the DW device  22 . Note that the SIP  18  should have a SIP workload management information at its disposal, such information corresponding to all the routing and parameters information. If it is not the case, the DW management is duplicated into the SIP  18 .  
         [0035]     When the SIP  18  has received all the necessary information as illustrated in  FIG. 2 , it becomes the active stream infrastructure which delivers the same level of service as the disconnected one.  
         [0036]     Finally, at the end of the service delivery set up, the DW device  22  informs any other workload managers or automatic provisioning system of the streaming system  14  that the traffic is now delivered by the new streaming system and that the associated resources that were used by the streaming system  14  can be used for other services.  
         [0037]     When it is decided to return to the original situation (e.g., because the traffic decreases) an action referenced as event B triggers the DW device  22  as illustrated in  FIG. 3 . The following steps are taken:  
         [0038]     the DW device  22  informs the SIP  18  (via fall back request  302 ) to stop delivering streaming service and requests the SIP  18  to forward back the user context  304 ;  
         [0039]     the user context  304  is immediately sent to the streaming system  14  via the DW device  22 ;  
         [0040]     the switch layer  16  is reconfigured (reconfiguration  306 ) by the DW device  22  so that the reconnection request is no longer re-routed;  
         [0041]     the DW device  22  sends a disconnection request  308  to the SIP  18  so the host  10  may try a new reconnection to the streaming system  14 .