WO2015147708A1

WO2015147708A1 - Allocated bitrate offering

Info

Publication number: WO2015147708A1
Application number: PCT/SE2014/050357
Authority: WO
Inventors: Paul Stjernholm
Original assignee: Telefonaktiebolaget L M Ericsson (Publ)
Priority date: 2014-03-24
Filing date: 2014-03-24
Publication date: 2015-10-01

Abstract

It is disclosed a system (10, 14, 70, 80, 90) for controlling that an offered bitrate, estimated by a mobile network (11), is provided by the mobile network and not exceeded by an application service (12). The method comprises offering (216, 316) by a mobile network (11, 72) an estimate of an available bitrate to the application service flow. Based on the estimate of the available bitrate, a bitrate of an application service flow may be adapted by the application service. When the bitrate of the application service flow exceeds the available bitrate estimate, the mobile network decreases the bitrate of the application service flow. The mobile network also allocates a bitrate of the application service flow unless the bitrate exceeds the available bitrate.

Description

ALLOCATED BITRATE OFFERING

TECHNICAL FIELD

This disclosure relates to bitrate offering. In more particular, it relates to offering of a bitrate that is allocated by a mobile network.

BACKGROUND

Mobile operators are today trying to optimize network capacity by applying functions in the service network which manipulates the service delivery. These functions may comprise pacing of data packets or content transcoding, and can be applied to Internet services that are not managed by the mobile operator, also known as over-the-top (OTT) services.

Many adaptive services, for instance dynamic adaptive streaming over hypertext transfer protocol (HTTP) (DASH), are adapted by the end-points of a connection, without intervention by an intermediate network. DASH is becoming a prevailing technique for delivering video services in mobile networks.

The manipulation of the service delivery by mobile operators is not appreciated by application service providers (ASP), for example Google, who want to manage their service delivery to the end-users and control the perceived quality-of-experience (QoE).

End-to-end adaptation, in for instance DASH, may result in a situation where different users running rate adaptive services individually will compete for the available radio resources, where the first to grab the resource will probably get it. Two drawbacks that come with end-to-end adaptation are that neither does it guarantee that the desired user gets its resources, nor that they are used to maximize the overall QoE among the users in the mobile network.

There is hence a need for a solution addressing one or more of these issues as discussed above. SUMMARY

It is an object of exemplary embodiments to address at least some of the issues outlined above, and this object and others are achieved by a system capable of allocating a bitrate to an application service flow of an application server and a method for allocating a bitrate to an application service flow of an application service, according to the appended independent claims, and by embodiments of the disclosure according to the dependent claims.

According to one aspect, the present disclosure provides a method in a system for allocating a bitrate to an application service flow of an application service. The method comprises offering by a mobile network an estimate of an available bitrate to the application service flow, enabling the application service to adapt the application service flow based on the estimate of the available bitrate to provide an application bitrate. The method also comprises decreasing by the mobile network the application bitrate, when the application bitrate exceeds the available bitrate. In addition, the method comprises allocating by the mobile network the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

According to another aspect, the present disclosure provides a system for allocating a bitrate to an application service flow of an application service. This system is adapted to offer an estimate of an available bitrate to the application service flow, enabling adapting the application service flow based on the estimate of the available bitrate to provide an application bitrate. The system is also adapted to decrease the application bitrate, when the application bitrate exceeds the available bitrate. In addition, it is also adapted to allocate the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

According to yet another aspect, the present disclosure provides a system for allocating a bitrate to an application service flow of an application service. This system comprises a mobile network and an application service. The mobile network is configured to offer an estimate of an available bitrate to the application service flow, enabling the application service to adapt the application service flow based on the estimate of the available bitrate to provide an application bitrate. The mobile network is also configured to decrease the application bitrate, when the application bitrate exceeds the available bitrate. The mobile network is further configured to allocate the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

According to yet another aspect, the present disclosure provides a system for allocating a bitrate to an application service flow of an application service. This system comprises a processor and a memory. The memory contains instructions executable by said processor, whereby said system is operative to offer an estimate of the available bitrate to the application service flow, enabling adapting the application service flow based on the estimate of the available bitrate to provide an application bitrate. The system is further operative to decrease the application bitrate, when the application bitrate exceeds the available bitrate. In addition, the system is also operative to allocate the adapted bitrate to the application service flow, unless the adapted bitrate exceeds the available bitrate.

According to still yet another aspect, the present disclosure provides a system for allocating an application bitrate to an application service flow of an application service. This system comprises means configured to offer an estimate of the available bitrate to the application service flow, enabling adapting the application service flow based on the estimate of the available bitrate to provide an application bitrate. The means is further configured to decrease the application bitrate, when the application bitrate exceeds the available bitrate. The means is further configured to allocate the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

According to still yet another aspect, the present disclosure provides a network node capable of allocating a bitrate to an application service flow of an application service. The network node is adapted to offer an estimate of an available bitrate to the application service flow, enabling adapting the application service flow based on the estimate of the available bitrate to provide an application bitrate. The network node is further adapted to decrease the application bitrate, when the application bitrate exceeds the available bitrate. In addition, the network node is also adapted to allocate the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

According to still yet another aspect, the present disclosure provides a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method for allocating an application bitrate to an application service flow of an application service, where the method comprises offering by a mobile network an estimate of an available bitrate to the application service flow, enabling adapting the application service flow based on the estimate of the available bitrate to provide an application bitrate, decreasing by the mobile network the application bitrate, when the application bitrate exceeds the available bitrate, and allocating by the mobile network the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

The present disclosure allows the mobile network to enforce a recommendation given to an application service, residing outside the mobile network, via an exposure interface, such as a service exposure gateway.

Embodiments of the present disclosure allow the mobile network to control radio resource utilization by coordinating the recommendations given to application services.

Embodiments also provide means for a reliable estimate to an application service of the available bitrate, as compared to end-to-end estimate attempts.

Embodiments also make the application service provider aware of the service delivery of for instance rate adaptive application services, to allow them to, for instance, adapt media rates or content sizes in application services provided.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described in more detail, and with reference to the accompanying drawings, in which:

Figures 1A and IB schematically illustrate communicating entities of systems according to embodiments of this disclosure;

Figures 2 and 3 present handshake diagrams of signalling according to examples of embodiments of the this disclosure;

Figures 4 and 5 illustrate flow charts of methods according to embodiments of this disclosure;

Figure 6 illustrates an example of a realization of a system of this disclosure; and

Figures 7 to 9 schematically illustrate systems/network nodes according to embodiments of this disclosure. DETAILED DESCRIPTION

In the following description, different embodiments of the exemplary embodiments will be described in more detail, with reference to accompanying drawings. For the purpose of explanation and not limitation, specific details are set forth, such as particular examples and techniques in order to provide a thorough understanding.

Manipulation of service delivery by mobile operators is not appreciated by application service providers (ASPs), for example Google, wanting to manage their service delivery to the end-users and control the perceived end-user quality-of-experience (QoE).

The end-to-end adaptation, for example in DASH, may rend in a situation where different users running rate adaptive services individually will compete for the available radio resources, and where the first user to request the resource can get it. This does neither guarantee that a desired user gets the resources nor that the resources are used to maximize the overall quality-of-experience (QoE) among the end-users in the mobile network.

There is hence a need for a different way to provide resources to end-users.

Figure 1A schematically illustrates communicating entities of system 10 according to embodiments of this disclosure. This example system 10 comprises a mobile network 11 and an application service 12.

Figure IB schematically illustrates communicating entities of system 14 according to embodiments of this disclosure. This example system 14 comprises a radio access network (RAN) 16, a core and/or service network 17 and an application service 18.

The present disclosure relates to offering of a bitrate that is allocated by a mobile network.

The embodiments in this disclosure are also related to the area of service exposure, where the mobile network offers services to external parties, for instance application service providers.

The embodiments in this disclosure concern exposure of an available bitrate to enable the application service to adapt the service bitrate, while being conscious and in control of the service delivery.

Figures 2 schematically illustrates a handshake diagram of signalling between a radio access network 202, a core and/or service network 204 and an application service 206, according to some example embodiments of the present disclosure.

In 208, an application service 206 sends application service information to the core and/or service network 204.

In 210, the core and/or service network 204 identifies an application service based on the received application service information. A policy related indicator is also assigned to the application service.

In 212, the core and/or service network 204 sends the policy related indicator to the radio access network 202. In 214, the radio access network determines an estimate of an available bitrate based on the received policy related indicator.

In 216, the radio access network 202 sends information about the estimate of the available bitrate to the application service 206.

In 218, the application service 206 adapts the bitrate of the application service flow based on the estimate of the available bitrate, creating an application bitrate.

In 220, the application service 206 sends application service information as well as an application service flow adapted to the available bitrate to the core and/or service network 204. Here the application service information may be an identity of the application service flow.

In 222, the core and/or service network 204 may now identify or confirm the application service based on the application service information received in 220. In addition, a policy related indicator is assigned to the application service flow. The core and/or service network may treat the service flow according to the decided policy ties to the service flow.

In 224, the policy related indicator, as assigned in 222, and the application service flow are here sent to the radio access network 202.

In 226, the radio access node 202 enforces the bitrate policy. The radio access network here tries to provide a bitrate to the application service flow of at least the available bitrate offered to the application service flow. In this handshake diagram the application service 206 informs the core and/or service network 204 of an imminent service and an associated application service flow. A traffic detection function of the core and/or service network may here be informed. Prior to establishing an application service and an application service flow to an end-user, application service information is thus communicated to the core and/or service network 204. The core and/or service network assign(s) a policy related indicator to the application service flow. This policy related indicator may be in the form of a flow tag. A policy may be enforced by the radio access node on the application service flow based on the flow tag. A bitrate of the application service flow may be decreased by the radio access node to fit the available bitrate.

Alternatively, the application service may inform a traffic detection function of the core and/or service network of an imminent service and the an associated service flow for which the core and/or service network sets up a dedicated bearer and assigns quality of service (QoS) parameters to the dedicated bearer. Example of QoS parameters are QoS class identifier (QCI) and allocation and retention priority (ARP).

The application service may hence adapt the bitrate of the application service flow according to an estimate of the available bitrate.

Figures 3 schematically illustrates an example of a handshake diagram of signalling between a radio access network 302, a core and/or service network 304 and an application service 306, according to some embodiments of the present disclosure. This handshake diagram is similar to the one as schematically illustrated in Figure 2. In fact most steps in Figure 3 are the same or at least substantially the same as the steps in Figure 2. Steps 314 to 326 are the same or substantially the same as the steps 214 to 226, for which reason the description related to Figure 2 will be referred to for these steps.

However, steps 308 to 312 differ from steps 208 to 212.

In 308, an application service flow is sent from the application service 306 to the core and/or service network 304. This is different in that the flow is directly sent to the core and/or service network, instead of only application service information as sent in 208. The core and/or service network 304 may identify 310 the application service based on the application service flow, and assign a policy related indicator to the application service flow.

The application service may alternatively be identified from an application service request sent from a communication device in the uplink.

In 312, core and/or service network 304 sends the policy related indicator as well as the application service flow itself to the radio access network 302.

A traffic detection function of the core and/or service network 304 may determine the application service in the associated service flow and assign the flow tag to the application service flow.

Alternatively, the traffic detection function may determine the application service in the associated service flow, and set up a dedicated bearer for the flow to which bearer it may assign a QoS parameter, for example an QCI and ARP.

Figure 4 illustrates a flow chart of a method for allocating a bitrate to an application service flow of an application service. In 42, the flowchart comprises offering by a mobile network an estimate of an available bitrate to the application service flow, enabling adapting the application service flow based on the estimate of the available bitrate to provide an application bitrate.

In 44, the flowchart comprises decreasing by the mobile network the application bitrate, when the application bitrate exceeds the available bitrate. In 46, the flowchart comprises allocating by the mobile network the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

The method for allocating a bitrate to an application service flow of an application service may further comprise identifying by a core and/or service network the application service flow, and wherein offering the estimate of the available bitrate may comprise offering the estimate of the available bitrate to the identified application service flow.

The method may further assigning by a core and/or service network a policy related indicator to the application service flow, and estimating by the mobile network the available bitrate based on policy related indicator.

Assigning a policy related indicator to the application flow within the method, may comprise assigning a flow tag to the application service flow. Assigning a policy related indicator to the application flow within the method, may comprise setting up a dedicated bearer for the application service flow, and assigning a quality of service, QoS, parameter to the dedicated bearer.

Identifying the application service flow within the method may comprise using, by the core and/or service network, packet inspection of the application service flow.

The method may comprise receiving, by the core and/or service network, application service information from the application service, and wherein identifying the application service flow may comprise identifying the application service flow based on the received application service information.

Adapting the application service flow may comprise adapting media rates or content sizes in application services provided.

It should be mentioned that allocating a bitrate may mean allocating resources for the bitrate.

It is pointed out that the available bitrate denotes a bitrate offered by the mobile network to the application service flow. The application bitrate is intended to denote a bitrate that is sent by the application service to the mobile network. This application bitrate may be adapted or may not be adapted.

Figure 5 illustrates a flow chart of an embodiment of a method for allocating a bitrate to an application service flow of an application service.

In 52 this flowchart comprises offering an estimate of the available bitrate. In 54, the flowchart comprises adapting an application service flow based on the estimate of the available bitrate. In 56, the flowchart comprises determining whether the application bitrate exceeds the available bitrate. If the application bitrate exceeds the available bitrate, the flowchart comprises step 58 of decreasing the application bitrate. The flowchart also comprises allocating 59 the application bitrate to the application service flow, unless the adapted bitrate exceeds the available bitrate.

The further description below will focus on a flow based scenario, that is a scenario in which a flow tag is determined by the core and/or service network based on the identification of the service and other information, for example subscription information.

However, it should be pointed out that the same principles can be applied on a dedicated bearer scenario, where a dedicated bearer is set up for the application service flow, and a policy related indicator comprises a QoS parameter, for example QCI and ARP, where a policy relates to a QoS policy for the dedicated bearer.

Returning to the flow based scenario, it can be mentioned that the flow tag applied to the service flow may be associated with a flow tag policy describing the policy to apply for a specific flow tag. The flow tag policy may be configured in RAN via the core and/or service network or a management system, for instance or be sent by dedicated control signaling. The flow tag policy may describe a packet treatment to apply to the flow, for instance packet drop policy and/or packet scheduling policy. In addition, the flow tag policy may also be associated with certain conditions in the RAN, for instance the resource utilization level, or load. The resulting policies applied may thus result in different treatment depending on system condition.

The policy governing a packet forwarding treatment may be described as one or more bitrate levels and may be associated with a priority level.

Table Example of a flow tag policy for a certain flow tag identity.

It is clear that the policy may take into account various load and bitrate conditions and allocates a priority according to load and bitrate conditions.

In RAN, as part of the radio resource management, the packet drop policy may be enforced by an active queue management function and the packet scheduling policy by a radio scheduling function in e.g. an eNodeB.

When applying a flow tag policy the radio resource management in RAN may also return a bit rate available for the service flow to the application service, where the available bitrate may apply until a new available bitrate is provided or for a certain amount of time.

Figure 6 illustrates an example of a schematic realization of a system of this disclosure. Especially the realization comprises a network solution for RAN service exposure of available bit rate. In further realizations other functions may also play a part as described below. Figure 6 comprises a 60 an application service (AS) 61, a traffic detection function (TDF) 62, a policy and charging rules function (PCRF) 63, a policy and charging enforcement function (PCEF) 64, a service exposure gateway (SXP) 65, a RAN 66, and an operating support system (OSS) 67.

The TDF 62 identifies the application service carried by the associated service flow, by either based on the application service information or by packet inspection, for instance deep packet inspection (DPI), of the application service flow itself. The application service (AS) and the associated service flow identity (SFID) are sent from the TDF 62 to the PCRF 63.

Based on the AS, and other available information, the PCRF 63 associates a flow tag with the service flow. The PCRF 63 returns the associated flow tag to the TDF 62 and also instructs the PCEF 64 to mark the service flow with the associated flow tag, for instance by using general packet radio system tunneling protocol (GTP) -U header extensions.

The SXP 65 provides an interface for the AS 61 to the mobile network. This interface is used to set up a control plane connection and associations between the AS and RAN 66. However this is outside the scope of this disclosure.

During an initial procedure the AS 61 may provide the SXP 655 a list of bit rates it is capable of adapting to. It should be emphasized that this list is optional and is not used by AS 61 that does not require a strict bandwidth and may use the available bit rate from RAN 66 to for instance adapt the content size to be delivered.

The SXP 65 may provide the list of bit rates to the TDF 62. In the TDF the list of bitrates may be associated with the corresponding flow tag for application service flow.

The list of bit rates may optionally be provided to the PCRF 63, for it to compile a flow tag policy to be used by the OSS 67. The flow tag policy may also be returned to the TDF 62.

The list of bitrates and the associated flow tag may be directly provided to RAN 66 by the TDF 62 over an established connection. RAN 66 will use the flow tag and the list of bitrates executing its flow tag policy in a packet forwarding treatment.

Optionally a flow tag policy is provided and used by RAN 66.

Executing the flow tag policy in RAN 66 an available bit rate is estimated, and provided to TDF 62. It is pointed out that the available bitrate may be selected from the list of bitrates provided by the AS.

The TDF 62 may provide the available bitrate directly to the AS, or via the SXP 65. The AS 61 now has the possibility to adapt to the available bitrate to optimize the quality of experience (QoE).

It is herein assumed that, if needed, the AS 61 itself maintains a control interface between the encoder and decoder sides of the connection to keep them synchronized.

The OSS 67 may be used to set flow policies and /or flow tag value ranges or to be used by the PCRF 63 for each AS.

The PCRF 63 may optionally send the flow tag policy to the management system of the mobile network, also denoted OSS 67. The OSS 67 may enrich the flow tag policy and provide it to RAN 66.

RAN 66 may optionally use the provided flow tag policy in the packet forwarding treatment.

It is noted that the TDF 62 has been described as one entity, although it may be divided into several entities communicating via internal interfaces. In a particular realization the functional distribution may differ to what is here indicated.

The present disclosure also comprises a system capable of allocating a bitrate to an application service flow of an application service, according to embodiments of this disclosure. This system is adapted to offer 216, 316, 42, 52 an estimate of an available bitrate to the application service flow, and to adapt 218, 318 a bitrate of the application service flow based the estimate of the available bitrate. The system is also adapted to decrease 226, 326 the application bitrate, when the application bitrate exceeds the available bitrate. In addition, it is also adapted to allocate 326, 326 the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

Figure 7 schematically illustrates a system 70 capable of allocating a bitrate to an application service flow of an application service, according to embodiments of this disclosure. This system comprises a mobile network 72 and an application service 74. The mobile network is configured to offer 42, 52, 216, 316 an estimate of an available bitrate to the application service flow, enabling the application service to adapt 54, 218, 318 the application service flow based on the estimate of the available bitrate to provide an application bitrate.

The mobile network is further configured to decrease 44, 326, 426 the application bitrate, when the application bitrate exceeds the available bitrate. The mobile network is further configured to allocate 46, 326, 426 the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

Figure 8 schematically illustrates a system 80 capable of allocating a bitrate to an application service flow of an application service, according to embodiments of this disclosure. This system 80 comprises a processor 82 and a memory 84. The memory contains instructions executable by said processor whereby said system 80 is operative to offer 42, 52, 216, 316 an estimate of the available bitrate to the application service flow, enabling adapting 54, 218, 318 the application service flow based on the estimate of the available bitrate to provide an application bitrate;; to decrease 226, 326 the application bitrate, when the application bitrate exceeds the available bitrate; and to allocate 226, 326 the adapted bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

Figure 9 schematically illustrates a system 90 capable of allocating a bitrate to an application service flow of an application service, according to embodiments of this disclosure. This system comprises means 92 configured to offer 42, 52, 216, 316 an estimate of the available bitrate to the application service flow, enabling adapting 54, 218, 318 the application service flow based on the estimate of the available bitrate to provide an application bitrate; The means is further configured to decrease 44, 26, 226, 326 the application bitrate, when the application bitrate exceeds the available bitrate. The means is further configured to allocate 46, 226, 326 the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

The present disclosure provides a network node 80, 90 capable of allocating a bitrate to an application service flow of an application service. The network node is adapted to offer an estimate of an available bitrate to the application service flow, enabling adapting the application service flow based on the estimate of the available bitrate to provide an application bitrate. The network node is further adapted to decrease the application bitrate, when the application bitrate exceeds the available bitrate. In addition, the network node is also adapted to allocate the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

Embodiments also make the application service provider aware of the service delivery of for instance rate adaptive application services.

It may be further noted that the above described embodiments are only given as examples and should not be limiting to the present exemplary embodiments, since other solutions, uses, objectives, and functions are apparent within the scope of the embodiments as claimed in the accompanying patent claims.

ABBREVIATIONS

AS application service

ARP allocation and retention priority

ASP AS provider

DASH dynamic adaptive streaming over HTTP

DL downlink

HTTP hyper-text transfer protocol

LTE long term evolution

OSS operating support system

OTT over-the-top

QCI QoS class indicator QoE quality of experience

QoS quality of service

PCEF policy and charging enforcement function

PCRF policy and charging rules function

RAN radio access network

SXP service exposure gateway

TDF traffic detection function

UE user equipment

UL uplink

Claims

A method in a system (10, 70, 80, 90) for allocating a bitrate to an application service flow of an application service (12, 18, 74, 206, 306) residing outside the mobile network , the method comprising:

offering (42, 52, 216, 316) by a mobile network (1 1, 72) an estimate of an available bitrate to the application service flow, enabling the application service to adapt (54, 218, 318) the application service flow based on the estimate of the available bitrate to provide an application bitrate;

decreasing (44, 58, 226, 326) by the mobile network (1 1, 72) the application bitrate, when the application bitrate exceeds the available bitrate; and

allocating (46, 59, 226, 326) by the mobile network ( 11, 72) the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

The method according to claim 1, further comprising identifying (210, 222, 310, 322) by a core and/or service network ( 17, 204, 304) the application service flow, and wherein offering (42, 52, 216, 316) the estimate of the available bitrate comprises offering the estimate of the available bitrate to the identified application service flow.

The method according to any of claims 1 or 2, comprising assigning (210, 310) by a core and/or service network (17, 204, 304) a policy related indicator to the application service flow, and estimating (214, 314) by the mobile network the available bitrate based on policy related indicator.

The method according to claim 3, wherein assigning (210, 310) a policy related indicator to the application flow, comprises assigning a flow tag to the application service flow.

The method according to claim 3, wherein assigning (210, 310) a policy related indicator to the application service flow, comprises setting up a dedicated bearer for the application service flow, and assigning a quality of service, QoS, to the dedicated bearer.

The method according to any of claims 2 to 5, wherein identifying (210, 310) the application service flow comprises using, by the core and/or service network, packet inspection of the application service flow.

7. The method according to any of claims 2 to 5, further comprising receiving (308), by the core and/or service network ( 17, 204, 304), application service information from the application service, and wherein identifying (210, 222, 310, 322) the application service flow is based on the received application service information.

8. A system (10, 14) capable of allocating a bitrate to an application service flow of an application service (12, 18, 74, 206, 306), the system being adapted to offer (42, 52, 216, 316) an estimate of an available bitrate to the application service flow, enabling adapting (54, 218, 318) the application service flow based on the estimate of the available bitrate to provide an application bitrate; to decrease (326, 426) the application bitrate, when the application bitrate exceeds the available bitrate; and to allocate (326, 426) the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

9. A system (10, 14, 70) capable of allocating a bitrate to an application service flow of an application service (12, 18, 74, 206, 306), the system comprising a mobile network (11) and the application service (12, 18, 74, 206, 306), wherein the mobile network is configured to offer (42, 52, 216, 316) an estimate of an available bitrate to the application service flow, enabling the application service to adapt (54, 218, 318) the application service flow based on the estimate of the available bitrate to provide an application bitrate; wherein the mobile network further is configured to decrease (326, 426) ) the application bitrate, when the application bitrate exceeds the available bitrate; and configured to allocate (326, 426) the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

10. A system (10, 14, 80) capable of allocating a bitrate to an application service flow of an application service (12, 18, 74, 206, 306), the system comprising a processor (82) and a memory (84), said memory containing instructions executable by said processor whereby said system (80) is operative to offer (42, 52, 216, 316) an estimate of the available bitrate to the application service flow, enabling the application service to adapt (54, 218, 318) the application service flow based on the estimate of the available bitrate to provide an application bitrate; to decrease (44, 226, 326) the application bitrate, when the application bitrate exceeds the available bitrate; and to allocate (46, 226, 326) the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

11. A system (10, 14, 90) capable of controlling an application service flow of an application service (12, 18, 74, 206, 306) to an available bitrate, the system comprising means adapted to offer (42, 52, 216, 316) an estimate of the available bitrate to the application service flow, enabling the application service to adapt (54, 218, 318) the application service flow based on the estimate of the available bitrate to provide an application bitrate; to decrease (44, 226, 326) the application bitrate, when the application bitrate exceeds the available bitrate; and to allocate (46, 226, 326) the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.

A computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 1 to 7.

A network node (80, 90) capable of allocating a bitrate to an application service flow of an application service (12, 18, 74, 206, 306), the network node being adapted to offer (42, 52, 216, 316) an estimate of an available bitrate to the application service flow, enabling adapting (54, 218, 318) the application service flow based on the estimate of the available bitrate to provide an application bitrate; to decrease (326, 426) the application bitrate, when the application bitrate exceeds the available bitrate; and to allocate (326, 426) the application bitrate to the application service flow, unless the application bitrate exceeds the available bitrate.