WO2008010673A1

WO2008010673A1 - Method for managing data transfer services on a network

Info

Publication number: WO2008010673A1
Application number: PCT/KR2007/003490
Authority: WO
Inventors: Yu Kyoung Song
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2006-07-19
Filing date: 2007-07-19
Publication date: 2008-01-24
Anticipated expiration: 2009-01-19

Abstract

The present invention relates to a method for managing traffic transfer services on a network. One of the present methods requests access allowance of a new connection to a network, selects a connection to be released from among blocking connections being in service if the request of access allowance is rejected, and invokes an action for requesting to release the selected blocking connection. The invoked action has an input argument carrying identifying information of the new connection. According to the action invocation, the selected blocking connection is pre-empted.

Description

D E S C R I P T I O N

METHOD FOR MANAGING DATA TRANSFER SERVICES ON A

NETWORK

1 . Technical Field The present invention is related to a method for managing content transfer services through a home network such as the one based on UPnP.

2. Background Art

Recently, inexpensive and pervasive networking technologies based on various small devices are emerging or being commercialized. People can make good use of various home appliances such as refrigerators, TVs, washing machines, PCs, and audio equipments once such appliances are connected to a home network. For the purpose of such home networking, UPnP™ (hereinafter, it is referred to as UPnP for short) specifications have been proposed.

A UPnP network consists of a plurality of UPnP devices, services, and control points. A service on a UPnP network represents a smallest control unit on the network, which is modeled by state variables. A CP (Control Point) on a UPnP network represents a control application equipped with functions for detecting and controlling other devices and/or services. A CP can be operated on an arbitrary device which is a physical device such as a PDA providing a user with a convenient interface. A CP can also constitute a single device together with another service, e.g., a renderer service which expresses images by rendering media data.

Therefore, multiple CPs can exist on a UPnP network and the user can control operations on a desired service by choosing a convenient

CP depending on his or her current location or employed device.

Once a home network as above is built in a particular place such as a home, the user can conveniently make use of desired operations (e.g., operations of duplicating or transferring data between separate devices) irrespective of his/her current location; moreover, multiple users can share the same device at the same time, in the same place. As described above, when multiple users use networked devices simultaneously or sequentially, or multiple tasks are carried out on networked devices simultaneously or sequentially, required quantity of data transmission may exceed transmission bandwidth provided by a network. In this case, network access for data transmission should be restricted.

For example, when additional network access is requested and bandwidth required by the request cannot be met by a current network while multiple content data are being streamed through the network, either the request is rej ected or the bandwidth occupied by a current streaming connection is retrieved to accommodate additional network access, eventually allocated to the additional network access . When such a case occurs, a network user using current transfer resources will experience an abrupt suspension of watching due to unknown reason, which causes complaints of network users.

3. Disclosure of the Invention

One objective of the present invention is to provide a method for managing traffic transfer services, the method, when available bandwidth is not sufficient for a new connection, retrieving resources for transfer service of the content being serviced in an optimal way and allocating the resources to a new connection.

Another objective of the present invention is to provide a method for informing the user of transfer resources retrieved after management of transfer service resources about the status of traffic transfer services, from which the cause of the retrieval can be identified.

One method for managing traffic transfer services on a network according to the present invention comprises requesting access allowance of a new connection to a network, determining a blocking connection to be released from among existing connections in service if access allowance of the new connection is rejected, and invoking an action for requesting release of the determined blocking connection, the action having an input argument carrying information identifying the new connection. Another method for managing traffic transfer services on a network according to the present invention comprises setting a state variable for managing connections, where the state variable includes fields for recording identifying information for connections to be released and identifying information for pre-empting connections, and when an action for requesting release of a blocking connection is received, registering identifying information of a new connection received from the action in the identifying information field for pre-empting connections within the state variable and generating an event notifying of the change of the state variable.

Another method for managing traffic transfer services on a network according to the present invention comprises preparing traffic descriptor at the user's request for establishing a connection to a network and invoking a request for connection establishment along with the traffic descriptor; when a success response to the invocation is received, requesting an event subscription to at least one of devices or services identified by connection path information received together with the success response and storing traffic handles within the traffic descriptor received together with the success response; and when an event occurs, checking whether a first traffic handle received through the event is contained in the stored traffic handles and if contained, obtaining connection information specified by a second traffic handle received through the occurred event.

In one embodiment according to the present invention, the information identifying a new connection is a traffic handle assigned to a traffic descriptor generated with respect to the new connection. In one embodiment according to the present invention, the action for requesting release of the determined blocking connection also includes information identifying the determined blocking connection in an input argument and the information identifying the determined blocking connection is a traffic handle assigned to a traffic descriptor generated with respect to the blocking connection.

In one embodiment according to the present invention, if a device or a service carrying out the steps of requesting access allowance of a new connection to a network, selecting a blocking connection, and invoking an action for requesting release of a blocking connection receives a success response after requesting access allowance of an arbitrary connection, the device or service informs a control application that requested establishment of the connection about path information of the connection. In the one embodiment, the path information of a connection comprises a list of UDN (Unique Device Name) and service ID of each device or service participating in transfer of traffic due to the corresponding connection. In one embodiment according to the present invention, the event generating step, if an action for requesting release of an arbitrary connection does not contain information identifying a different connection other than the arbitrary connection, records an invalid value in the identifying information field for pre-empting connections and generates an event notifying of change of the state variable. At this moment, a field value indicating the number of successfully released connections within the state variable is increased.

In one embodiment according to the present invention, after the step of obtaining connection information specified by a second traffic handle received through the generated event, a process is carried out to notify that a connection specified by the first traffic handle has been released, at least along with part of connection information specified by the obtained second traffic handle.

In one embodiment according to the present invention, the step of subscribing to an event and storing a traffic handle within traffic descriptor received along with a success response requests event subscription to only a device or service corresponding to a source among devices or services identified by the received connection path information.

In one embodiment according to the present invention, the event subscription is subscription to an event notifying of occurrence of pre-empting a connection. In another embodiment according to the present invention, the event subscription is subscription to an event notifying of occurrence of releasing a connection.

4. Brief Description of the Drawings

Fig. 1 illustrates a flow diagram of releasing a servicing connection for content according to one embodiment of the present invention;

Fig. 2 illustrates a method for selecting a connection to be released according to one embodiment of the present invention;

Fig. 3 illustrates a signal exchange procedure among devices or services for releasing a servicing connection for content according to one embodiment of the present invention;

Fig. 4 illustrates a structure of a state variable defined for a device or a service that carries out actual transfer of traffic to manage connections according to one embodiment of the present invention; and

Fig. 5 illustrates a structure of an action for releasing a connection used for pre-empting a connection for traffic according to one embodiment of the present invention. 5. Best Mode for Carrying Out the Invention

Hereinafter, embodiments of the present invention will be described in detail with reference to appended drawings.

In one embodiment according to the present invention, at the time of requesting allowance of access to a network for content data transfer, information which describes traffic conducting the transfer (which is also called as traffic descriptor and from now on, is referred to as ^λTD information' for short) is delivered to a manager that processes/manages requests for allowance of access. (Hereinafter, it is referred to as ^vQoS (Quality of Service) manager' .) TD information includes type of the corresponding traffic (e.g., information indicating realtime data (streaming data) or non-realtime data) , information indicating applicability of change of service quality, and also information specifying conditions depending on service quality (e.g., HD (High Definition) or SD (Standard Definition) ) of the corresponding traffic (which is also called as ^vTspec information') . Tspec information includes information about service rate required for streaming of traffic of particular service quality.

The above terms such as TD, Tspec, etc are not main point to the present invention and therefore can be replaced with different terms .

In the following, an embodiment of releasing a connection for transfer of content being serviced according to the present invention is described. Fig. 1 illustrates one example of a flow diagram regarding to the above. As shown in the figure, when a request for a new connection (a request for allowance of access to a network) is made (SIl) , service rate of the quality specified in TD information accompanying the request (service rate specified in Tspec information which is set as active in TD information) is checked and whether the required bandwidth is available within current remaining bandwidth (unoccupied bandwidth after subtracting bandwidth reserved for streaming and so on from total available bandwidth provided by a network) is determined (S12) . If the required bandwidth can be accommodated, a request for a new connection is accepted (Slβ) , otherwise service rate of a connection (or sum of service rates of connections) selected among current servicing connections after a selection policy, which is to be described later, is compared with that of the new connection required in addition to available bandwidth (S13) . If the former is larger than the latter, a current servicing connection (s) is released (S14), otherwise the newly requested connection is rejected (S19) . In another embodiment according to the present invention, instead of releasing a connection, service quality of the connection can be degraded. Retrieved bandwidth is calculated by difference between original bandwidth and degraded bandwidth and connections to degrade are selected according to sum of the calculated bandwidth.

As one example of the selection policy, among "inferior blocking connections" of a newly requested connection, connections that can be released for securing necessary bandwidth are selected in the increasing order of priority. In the selected connections, a combination of connections is selected, where the combination provides necessary bandwidth and at the same time, the number of connections to be released is kept as small as possible. At this point, an "inferior blocking connection" denotes the one from among blocking connections being in service and whose priority information, e.g. , UIN (User Importance Number) , is lower than that of a newly requested connection. Namely, in the example of Fig. 2, connections A, B, C, and D are inferior blocking connections with respect to a newly requested connection E.

Fig. 2 illustrates specifically a method for selecting a connection to be released according to one example of a selection policy. As shown in the figure, before a new connection is requested, bandwidth occupied by current servicing connections is 95 Mbps on a network of 100 Mbps bandwidth. When a new connection for streaming of AV data (connection E) is requested (S23a) and the new connection has TD information such that Tspec marked as active is 15 Mbps and UIN is set as 50, among inferior blocking connections (connections A, B, C, and D) with respect to the new connection, a preliminary group of connections is formed, where release of the connections starting from the lowest UIN yields necessary bandwidth, namely, 15 Mbps . Blocking connections are finally selected in such a way that among the preliminary group of connections, the number of connections to be released are kept smallest and at the same time, total available bandwidth secured from the release is larger than necessary bandwidth (S23b) . Put another way, a lowest UIN is selected from among UINs yielding total available bandwidth larger than necessary bandwidth, the total available bandwidth being secured by choosing a particular UIN among individual UINs of current servicing connections and releasing connections with UINs lower than the particular UIN. Blocking connections are finally selected from connections of UINs lower than the selected UIN in such a way that the number of released connections is kept as small as possible and total available bandwidth secured from the release is larger than necessary bandwidth.

According to the above selection scheme, in the example of Fig. 2, since connections B, C, and D can yield total available bandwidth of 18 Mbps in a preliminary selection procedure, the above connections are selected (that is, as a reference of pre-emption, UIN 30 is determined) . Among the selected connections (among connections, each UIN of which is lower than a determined pre-emption reference, 30) , a combination of connections where the number of connections to be released is smallest and total available bandwidth is still larger than necessary bandwidth namely, connections B and D is finally selected. Network resources for finally selected connections are pre-empted and used for a new connection. In other words, finally selected connections are released (S23c) and a newly requested connection (connection E) is accommodated.

As a matter of course, in the example of Fig.2, if UIN utilized to retrieve required network resources is the same as or higher than the UIN of a new connection, the newly requested connection is rejected.

Fig. 3 illustrates a signal exchange procedure among devices according to one embodiment of the present invention for allowing connections for transfer services and at the lack of transfer resources, releasing an inferior blocking connection being in service .

The procedure illustrated in Fig. 3 describes only a specific application of a signal exchange method between various devices for releasing a connection; principles and purpose of the present invention are not limited to the illustrated procedure in Fig. 3. Therefore, inventions employing different signal exchange methods but utilizing principles and purpose suggested in the description of the present invention should necessarily be considered to belong to the scope of the present invention.

First, when a connection request for streaming content is made through a control point 15 from the user, the control point 15 configures TD information for the connection and requests (S31) connection establishment from an arbitrary QoS manager 14. (A different QoS manager 12 in the figure can also be used for this purpose . For the convenience of description of the present invention, relationship between a control point and a QoS manager selected by the control point for connection establishment is described in terms of the letter A and B introduced in the figure.) Information about source and destination of a connection designated by the information selected by the user is also contained in the TD information configured by the control point 15. Information about a source and a destination is composed of, e.g. , UDN (Unique Device Name) of a device or a service that becomes a source or a destination and a service identifier (Service ID) . The QoS manager 14 that has received the request for connection establishment creates a traffic handle that is composed of string information this information is used for unique identification and management of TD information (that is, a connection for traffic transfer) among devices, where a device may imply a 'service' within the device and in the following, the term of 'device' can alternatively indicate a 'service' unless description of operations is impaired and records the traffic handle within the received TD information (TDl) (before this recording, the corresponding fields within TD information exchanged among devices and/or services are left blank or filled with NULL) . The QoS manager 14 provides TD information for a QoS policy holder (QPH) (not shown) and requests inquiry of priority information about a requested connection. The QoS policy holder determines priority information according to a priority determination policy or algorithm applied already thereto. The determination is made by applying information such as identifying information of the user who requests access and type of traffic requested for access (e.g., whether it is of AV data or traffic 5 for external call at emergency) to its policy or algorithm. According to the determination, e.g., TIN (Traffic Importance Number) and UIN are determined as priority information, which is subsequently recorded in TD information and returned to the QoS manager 14 in response to the inquiry request .

10 The QoS manager 14 that received the returned TD information determines a traffic path based on source and destination information within the TD information. According to the path determination, besides individual QoS devices corresponding to a source and a destination, QoS devices through which traffic passes

15 can be included in the path. Once a path is determined, an action for requesting allowance of access to a network (AdmitTrafficQoS () ) is invoked on each individual QoS device on the path (including individual QoS devices at the source and destination) (a QoS device 13 in the example of Fig. 3) by loading the returned TD information

20 into the action (S32) .

The QoS device 13 of Fig. 3 represents a source and a destination device to establish a connection, and also applies to the case of multiple devices when other devices exist on a data transmission path between the two devices; in what follows, the

25 term of ^xQoS device' should be understood as a device or a service of the above meaning unless it is specifically prefixed with a modifier such as 'individual'.

In regard to the request, when connection allowance is given from the QoS device 13 since current bandwidth available can

30 accommodate requested bandwidth (in reality, "Admitted" response is received from each individual QoS device on the path) (S33), the QoS manager 14 fills TD information with identifying information of individual QoS devices (e.g., UDN and service ID) belonging to the path of an admitted connection and provides the control point

35 15 with the identifying information, thereby delivering an OK response to the request for connection establishment (RequestTrafficQoS () ) (S34) . Identifying information about individual QoS devices on a path can also be filled into the TD information when access allowance to the QoS device 13 is invoked (S33) .

Meanwhile, the QoS device 13, in order to manage connections that it has admitted, assigns and manages a state variable in the name of, e.g., "MostRecentStreamAction" . The state variable has internal fields as shown in Fig. 4 according to one embodiment of the present invention. The state variable is an evented state variable which generates an event when the value of a field changes. The upper three fields 401 among illustrated fields are those counting the number of successful invocations of an action with a name indicated in the table of Fig. 4. The lower two fields 402 are those for the case of releasing or pre-empting a connection of traffic being in service, functions of which are described later with exemplified applications thereof. Since invocation of an action for requesting connection admittance (AdmitTrafficQoS ( ) ) has been successfully made, the field value of AdmitTrafficQos is increased by one and accordingly, an event is generated as the value has been changed. A device or a control point that is subscribed to the corresponding event receives the event and carries out a relevant procedure. Since the procedure has no immediate relevance to the present invention, further description thereon is not provided.

The control point 15 that received an OK response with respect to a request for connection establishment (RequestTrafficQos ( ) ) stores a traffic handle contained within TD information as a connection created by its own invocation, the TD information being received as a response. With reference to identifying information of individual QoS devices on a path within received TD information, the control point 15 also requests subscription to a 'pre-emption' event (or a connection release event) for a device corresponding to the source of the path (S35) . In another embodiment according to the present invention, the control point 15 can request subscription to a 'pre-emption' event (or a connection release event) for each individual QoS device belonging to a path within received TD information. After subscription to the event, when the value of a state variable which is under the management of a subscribing QoS device associated with the event exhibits a change , a device which has subscribed to the event , i.e., the control point 15 generates an event. This is called as 'eventing' .

Apart from the event subscription, user-requested traffic, e.g., streaming of AV data is carried out between user-designated devices by additional invocation of an action by the control point 15 and/or information exchange in accordance with a relevant protocol between a traffic source and a destination device. Since the procedure also has no immediate relevance to the present invention, further description thereon is not provided.

While more than one connection is handling traffic transfer on a network according to the steps ranging from S31 to S35, if a connection request for the content to be streamed is made (S41) from the user through the control point 15 and a different control point 11 (it should not necessarily be a different control point; for the case of the same control point, the following description equally applies) , the control point 11 configures TD information

(TDk) for the connection in the same way described earlier and requests connection establishment on a QoS manager 12 that the control point 11 has selected (S41) . The QoS manager 12 that received the request assigns a traffic handle to TD information, provides the TD information for a QoS policy holder (QPH) (not shown) , and requests inquiry of priority information (e.g., UIN and/or TIN) about a requested connection. The QoS policy holder then determines priority information according to a priority determination policy or algorithm applied already thereto, fills TD information with the priority information, and returns TD information to the QoS manager 12 in response to the inquiry request . Subsequently the QoS manager 12 loads the TD information into an action, thus requesting (S42) allowance of access to a network on the QoS device 13. Although the QoS device 13 belonging to a traffic path described by the steps of S31 through S35 has been assumed to belong to a currently requested traffic path for simplicity of figures and description of the present invention, in practice the present description and figures also include the case where an arbitrary single QoS device is employed doubly on determined paths of separate traffic .

The QoS device 13 , when it cannot accommodate service rate requested by the TD information with current bandwidth available, makes a response notifying of not admitting a connection (S43) . This applies equally to the case where at least one QoS device rather than all of individual QoS devices on the path cannot accommodate requested bandwidth, thereby responding by not admitting a connection.

When a request for connection allowance is rejected (when ^λno admittance' is received from at least one individual QoS device) , the QoS manager 12 requests information about servicing connections from the QoS device 13 (in practice, an individual QoS device that issued 'no admittance') (S44) , and obtains TD information about all the servicing connections (TDl, .. ,TDk, ..) from the QoS device 13 according to the request (S45) . The QoS manager 12 then checks priority information, namely UIN, corresponding to each obtained TD information and determines those connections having UINs lower than that of a connection that has been previously rejected for access as inferior blocking connections.

Among inferior blocking connections determined in the above manner, an inferior blocking connection or connections to be released are selected according to the selection method described with reference to Fig. 2 (SSl) . For each of selected connections, a necessary procedure for releasing is carried out . In the following, description of a procedure for releasing one connection (a connection whose corresponding TD information is TDl) among the selected connections is provided. In another embodiment according to the present invention, instead of releasing a connection, a procedure for degrading service quality can be carried out.

The QoS manager 12 invokes a traffic release action (ReleaseTrafficQoS () ) requesting release one (the connection of TDl) of the selected connections on the QoS device 13 (in practice on the QoS device that rejected a request for access allowance) (S46) . The traffic release action (ReleaseTrafficQoS ()) invoked at this point has a structure as shown in Fig. 5. As shown in the figure, input arguments of 'ReleaseTrafficHandle' and ' PreemptionTrafficHandle ' are loaded into a traffic release action .

That is, the QoS manager 12 loads a traffic handle which has been assigned to TDK by the QoS manager 12 into λ PreemptionTRafficHandle' and loads a traffic handle recorded in TD information (TDl) selected previously for release into ^v ReleaseTrafficHandle' .

The traffic release action (ReleaseTrafficQoS ()) is also used for the case when a connection is released through a normal procedure for example, when release of a connection is requested from a control point by the request of the user who has established the corresponding connection in addition to the case of releasing a connection for pre-empting to allow access of another connection as done in the step S4β. But in this case, either ' PreemptionTrafficHandle ', which is one of input arguments shown in Fig. 5, carries an invalid handle value such as "NULL" or input argument of ^λ PreemptionTrafficHandle' is not contained in the action.

In another embodiment according to the present invention, an action used for pre-empting a connection of low priority is distinguished from the name of an action used for releasing a connection in a general situation. For example, an action for pre-empting traffic uses a name of "PreemptTrafficQos" . This action also has an input argument as illustrated in Fig. 5.

Upon invocation (S46) of the traffic release action or traffic pre-emption action, the QoS device 13, according to a received action, changes the value of a connection management state variable "MostRecentStreamAction" that is under management thereof. For example, since a received action is a traffic release action, the value of a field (ReleaseTrafficQos) of the connection management state variable is increased by one and the values contained in an input argument (ReleaseTrafficHandle and PreemptionTrafficHandle of Fig. 5) of the action are copied to the corresponding fields (ReleaseTrafficHandle and PreemptionTrafficHandle) , respectively. This applies equally to the case when a traffic pre-emption action (PreemptTrafficQoS () ) is used. Unless an input argument of

PreemptionTrafficHandle is contained in a received traffic release action, an invalid value such as "NULL" is recorded in the field PreemptionTrafficHandle of a connection management state variable. The QoS device 13, before or along with updating the value of a connection management state variable as above, requests an operation for stopping transfer of traffic specified by an input argument ReleaseTrafficHandle of a traffic release action (or a traffic pre-emption action) on a physical transfer means.

Since the connection management state variable is defined as an evented state variable, the QoS device 13 generates an event according to the update of the variable. If the value of PreemptionTrafficHandle has been updated, a pre-emption event (Event : Preemption) is generated; if the values of ReleaseTrafficQos and ReleaseTrafficHandle have been updated with the value of PreemptionTrafficHandle intact (namely, if it is kept in the "NULL" state), a connection release event (Event : Release) is generated (S36) . At the occurrence of an event, a connection management state variable "MostRecentStreamAction" under management of the QoS device 13 is delivered together with the event and a device that has previously subscribed to the event becomes the object of eventing. In another embodiment of the present invention, a preemption event and a connection release event are not distinguished from each other but are generated as a single event. This is possible because a device or a control point that has received eventing can know the cause of eventing through the event and an associated connection management state variable.

The generated event is delivered to a control point 15 of A group that has already subscribed to the corresponding event S35. The control point that has received the event first checks whether the value of ReleaseTrafficHandle within the information received through the event is already in it. Unless the value is found in it which implies that a released connection is not the one that the control point 15 has requested for establishment the control point 15 ignores the released connection. On the other hand, if the value is found in it, the control point 15 checks the value of PreemptionTrafficHandle in the information received through an event. If the value is "NULL" and a generated event is a 'pre-emption' event, it implies an event error and therefore, the event is ignored. On the other hand, if the value is "NULL" and a generated event is a 'connection release' event, since it implies a normal release of a connection other than the one from pre-emption, the control point 15 handles the event according to a normal procedure. If the value of PreemptionTrafficHandle is valid irrespective of being a pre-emption event or a connection release event, the control point 15 invokes a TD browsing action "BrowseAllTrafficDescriptors ( ) " (S37) on an arbitrary QoS manager, e.g., the QoS manager 14 and the QoS manager 14 provides a list of TD information for the control point 15 in response to the invocation (S38) . The QoS manager 14, to provide the list of TD information for the control point 15, receives the list of TD information from the QoS device 13 through an action "GetQosState () " as done in the S44 step.

The control point 15 that received the list of TD information searches the received list of TD information for TD information whose traffic handle field is assigned the same value as a previously checked field PreemptionTrafficHandle and provides the user with user information, traffic type and/or priority information, and the like within the found TD information as the information of a pre-empting connection through a relevant UI (S39) . That is, a servicing connection that has been requested and allowed for access notifies of stopping of transfer service due to occupation of network resources by a different connection having provided information. Along with the above, the control point 15, from among traffic handles that have been stored and managed by the control point itself 15, deletes a traffic handle having the same value as the ReleaseTrafficHandle received through the event.

When information about a connection that has stopped transfer service (that is, a connection that is identified by the

ReleaseTrafficHandle) is needed e.g., when user priority information is needed, the information can be provided together with information about a pre-empted connection obtained from TD information within the received list of TD information, the TD information containing the same traffic handle as

ReleaseTrafficHandle received through the generated event . For instance, a notification message such as "Your traffic transfer service having priority K(<N) has been stopped due to the network access of another traffic having priority N and requested service rate XX Mbps ! " can be provided for the user. By doing this, the user using transfer service, e.g., watching streaming content can know the cause of suspension of screen display and if necessary, the user can again request content streaming in low quality, thereby being able to use transfer service within the allowed limit of network resources .

Meanwhile, the QoS device 13 carries out stopping transfer of traffic specified by an input argument ReleaseTrafficHandle of a received traffic release action (S46) , updating a connection management state variable, and making an OK response with respect to the received traffic release action after occurrence of an event (S47) . The QoS manager 12, when an OK response is received with respect to the invocation of a traffic release action, requests again allowance of access on the QoS device 13 by using TD information (TDk) of a connection rejected at the previous request for allowance of access (S48) . The QoS device 13, if it can accommodate service rate requested by active Tspec of TD information (TDk) accompanying a received access request, provides a response allowing the access (S49-1) and issues an OK response to the control point 11 with respect to the traffic request action

(RequestTrafficQoS ( ) ) (S41) according to the allowance response (S49-2) .

At least one embodiment of the present invention described through a limited number of embodiments above allows data service through a network, e.g., releasing streaming service or changing service quality of the content in an appropriate way for other transfer services of higher priority to be accommodated, thereby enabling systematic use of network resources. If service of a connection is stopped during the above process, the user is allowed to know the cause thereof, thereby dissatisfaction factors of the user in using a network being removed beforehand.

The foregoing description of a preferred embodiment of the present invention has been presented for purposes of illustration. Thus, those skilled in the art may utilize the invention and various embodiments with improvements, modifications, substitutions, or additions within the spirit and scope of the invention as defined by the following appended claims.

Claims

C LA I M S

1. A method for managing traffic transfer services on a network, comprising: requesting access allowance of a first connection; determining a second connection to be released from among existing connections in service when access allowance of the first connection is rejected; and invoking an action for requesting release of the determined second connection, the action having an input argument carrying information identifying the first connection.

2. The method of claim 1, wherein the information identifying the first connection is a traffic handle assigned to a traffic descriptor created for the first connection.

3. The method of claim 1, wherein the action further has an input argument carrying information identifying the second connection.

4. The method of claim 1, wherein the determining step comprises : requesting a device to send information about all connections in service and receiving the information about all connections in service, the device being one that rejected access allowance of the first connection; and based on the received information about connections, determining one or more connections, among connections having priority lower than that of the first connection, as the second connection to be released.

5. The method of claim 1, further comprising: re-requesting access allowance of the first connection when an admitted response is received for the invoked action requesting release of the second connection; and transmitting a success response to a control application that requested establishment of the first connection, when admittance is received in response to the re-requesting, .

6. The method of claim 1, further comprising informing a control application of path information of an arbitrary connection when a success response is received in response to a request of access allowance of the arbitrary connection, the control application having requested establishment of the arbitrary connection .

7. The method of claim 6, wherein the path information of a connection comprises a list of UDN (Unique Device Name) and service

ID of each device or service participating in transfer of traffic generated by the connection.

8. A method for managing traffic transfer services on a network, comprising: setting a state variable for managing connections, the state variable including fields for recording identifying information for a connection to be released and identifying information for a pre-empting connection; and when an action for requesting release of a first connection is received, registering identifying information of a second connection received from the action in the field for identifying information for a pre-empting connection within the state variable, and generating an event notifying of change of the state variable.

9. The method of claim 8, wherein the event generating step further comprises: stopping transfer of traffic generated by the first connection and increasing by one value of a field indicating number of successfully-released connections when the action is received, the field being included in the state variable; and transmitting a success response for the action.

10. The method of claim 8, wherein if an action for requesting release of an arbitrary connection does not contain information identifying a connection other than the arbitrary connection, the event generating step records an invalid value in the identifying information field for a pre-empting connection, and generates an event notifying of change of the state variable.

11. The method of claim 8 , wherein the identifying information of the second connection is a traffic handle assigned to a traffic descriptor generated for the second connection.

12. A method for managing traffic transfer services on a network, comprising: preparing a traffic descriptor at a user's request for establishing a connection to a network and invoking a request for connection establishment along with the traffic descriptor; when a success response to the invocation is received, requesting an event subscription to at least one of devices or services identified by connection path information received together with the success response, and storing a traffic handle within the traffic descriptor received together with the success response; and when an event occurs, checking whether a first traffic handle received through the event is contained in stored traffic handles and if contained, obtaining connection information identified by a second traffic handle received through the occurred event.

13. The method of claim 12, wherein the obtaining step requests an arbitrary device among devices managing traffic to send a list of information about all connections in service, receives the list from the device, searches the received list for a traffic descriptor to which a traffic handle identical to the second traffic handle is assigned, and obtains connection information from the found traffic descriptor.

14. The method of claim 12, further comprising deleting a traffic handle that is already stored and has a value identical to the first traffic handle.

15. The method of claim 12, further comprising notifying that a connection identified by the first traffic handle has been released, along with some of the connection information identified by the obtained second traffic handle.

16. The method of claim 12, wherein the event subscription is to subscribe to an event that is notified on occurrence of connection pre-emption.

17. The method of claim 12, wherein the event subscription is to subscribe to an event that is notified on occurrence of connection release.

18. The method of claim 12, wherein the storing step requests event subscription to only a device or a service corresponding to a source among devices or services identified by the received connection path information.

19. The method of claim 12, wherein the received connection path information includes a list of UDN (Unique Device Name) and service ID of each device or service participating in transfer of traffic generated by the connection.