GB2523534A - A telecommunications network and terminal - Google Patents

Abstract

A mobile telecommunications network has a content optimisation means in the core network which differentially marks IP packets of a specific service flow based on aspects of the service. The radio access network schedules traffic based on the marking. Packets may be marked within the DSCP code point. Packets in a video service flow may be marked high priority at session initiation or during congestion to improve customer experience. Specific packets of web content may be marked high priority if they impact on click-to-view time. An application running on a mobile device (UE) marks IP packets with a priority based upon the event that triggered the service or on knowledge of customer perception of what triggered the service event. Specific email requests are given a higher priority than background email downloads.

Description

Prioritisation within a Service Mobile networks today carry a wide range of traffic types, however aLl traffic is generaRy carried at an equal priority over the radio access network. Networks typicalLy support prioritisation on a customer basis and prioritisation on a bearer basis -where aLl traffic matching a specific criteria is given the same priority (e.g. Traffic with a given Source/Destination Address.). See for example Figure 1.

A) Service aware entities have been introduced into MobiLe Networks today in the Core network (Gi-LAN) and operate on the User data path of the customer. See architectures of 30 and Lii in Figure 2.

These entities typicalLy focus on the optimisation of Video and Web services, and generally there 3 different categories of optimisation which can co-exist: 1) Transport delivery: The Optimisation platform monitors the data stream associated with a video session and controls the flow of packets from the content If) source to the customer, thereby Limiting the amount of data stored in the Client play-out buffer in the customers device. At the start of the session, data is alLowed _ to fLow unhindered, but when the client buffer reaches a predefined level the O Optimisation platform imposes a restriction on the data rate.

The drawback of this approach is that even though the data rate of the 14') customer traffic is limited, the traffic is treated at the same priority as traffic which has a direct bearing on user experience.

2) TCP Optimisation: The Optimisation platform can also perform operations on the TCP connection of the Platform, in that the TCP connection is terminated towards the UE, and between the Content provider, e.g. Breaking the end-to-end TCP connection, and creating two separate bridged TCP connections at the Optimisation platform, in this way it reduces the perceived Latency, and aLLows the connection to be more reactive to changes in radio conditions.

3) Content Optimisation: The Optimisation pLatform may also modify the content which is being served to the customer, e.g. transcoding/compressing video or images from webpages so as to use less radio resources.

B) In the radio, further optimisation techniques are possible for the delivery of video.

It has been proposed that: a) An additionaL radio bearer is estabLished when a UE starts to receive video content, as described beLow as shown in figure 3. Note S/P-GW can be configured to set the Transport Layer DSCP on 55/8/1.

b) the RAN node (e.g. eNB) wouLd be configured to deLiver a very high-priority for a period of time or voLume of packets/data at the start of the bearer, alLowing video playback to start quicker at the device.

One drawback to this soLution is that the RAN is not aware of the needs of the content or the pLay-out buffer status, and therefore the mandating of a higher priority for a period of time or for a certain payLoad would have to be over dimensioned to ensure that the majority of videos see a benefit.

-For instance -different videos require different codec data rates, and therefore the data voLume for the first 3Oseconds of video would vary considerabLy.

-The prioritisation time wouLd aLso vary considerabLy depending on the radio LI') congestion -as it wouLd impact the achieved data rate of the UE and therefore the data voLume which has been passed N--ALso the RAN is not aware if there are muLtiple streams being downLoaded by C a IJE, or if it is a singLe stream, and therefore wouLd be unaware whether double the data rate wouLd be required, or whether the prioritisation period LI') wouLd need to be restarted at the request of the second video.

An aLternative mechanism is being devised for the prioritisation of Data within the 3G/LTE system whereby each service is marked within the DSCP code point of the IP packets, to indicate the service e.g. Video. See Figure 4, note S/P-GW can be configured to map AppLication Layer DSCP to Transport Layer DSCP on S5/8/1.

The RAN (e.g. eNB) would then prioritise the packets based on the DSCP code point, instead of the priority of the bearer that the packet was received from, and is described in FigureS.

Proposal 1: DifferentiaL Downtink Priority based on Service State This proposal is an alternative/enhancement to 1) and B) described above. The proposal could be performed in addition to, or instead of, the features of the optimisation pLatform described above such as the process of limiting the throughput.

Instead of marking the DSCP of the IP packets based on Service, the Optimisation platform may mark the DSCP based on the priority of the packets to be delivered -which would be set based on the state/status of the service which is included within the IP packets.

For exampLe for Video, a number of exemplary implementations may be considered.

See Figure 6.

In a first scenario, at session initialisation: -The Optimisation platform marks the DSCP of the IP packets associated with the Video with a DSCP code point indicating high priority.

-the Optimisation platform is aware of the Video codec data rate, and therefore 1"-can mark the necessary packets with a higher priority.

0 -The Optimisation platform tracks the delivery of the packets and onLy when the delivered packets exceeds the playout time by for example 20 secs (impLying that the pLayout buffer of the client includes 20 seconds of video), the optimisation may Lower the priority by using a different DSCF marking.

In a second scenario, at Congestion/Poor Radio conditions: -The optimisation platform may track the pLayout buffer size in the client and if it falls below a pre-defined level e.g.1 5s, the platform increases the marked priority of the packet such that more packets are comparativeLy delivered to the client to fill the buffer and therefore enhance user experience.

In a third scenario, at packet loss -When then Optimisation pLatform sees TCP retransmissions are required, the Optimisation platform can again increase the marked priority of the packet, to allow the TCP to recover quicker, and once the TCP connection is back up to full speed again, the priority can be lowered again.

The Optimisation platform can also configure the thresholds or optimisation (e.g. based on the specific device type, client), as some client implementations require greater volumes of data to be received prior to video playback commencing.

As will be seen, the user experience can be considerably enhanced as a result of the packets to be delivered being marked with a high priority based on aspects orthe nature of the service itseLf or based on the service fLow or service state.

For Web content, a similar mechanism can be introduced, whereby the aspects of the web page which have an implication on click-to-view time are prioritised, see Figure 7.

For exampLe, when Loading a webpage. certain tasks may need to be performed before other tasks can be performed. For example, DNS lookup needs to be performed before certain packets can be loaded. Additionally, scripts may need to be downloaded and run before further data packets are downloaded. In another example, style sheet packets may need to be downLoaded and these packets then reference further media for download. OnLy once the style sheet has been downloaded can the next step of the webpage download/rendering be performed. It would therefore be beneficial if this packet type was prioritised to reduce the bottleneck caused and to increase the user experience. In summary, those packets U') which have a direct bearing on click-to-view time are given a high priority. In other words, those data/packets which have dependent data/packets may be given a higher priority It may aLso be the case that the packets are marked based on the domain from which each packet originated.

Proposal 2: DifferentiaL Uptink Priority based on Service State Within the 3GPP QoS framework it is also possible to statically configure muLtiple Bearers between the UE and the P-GW.

See Figure 8.

The routing of the IP packets between bearers is dependent on the IP Rules configured by the network, and this can be on the DSCP, Source/Destination IP address, port numbers etc. See Figure 9.

It is proposed a scheme is adopted within the uplink, where the Applications are responsible for marking the DSCP of uplink packets instead of being based on a specific service: IC) e.g. Email = DSCP code point 1, Video = code point 2, etc. The Application in the device wouLd set the DSCP in dependence on the direct impact 0 to user experience within a specific service.

If) For exampLe an email woud either be set to Code point A or B in dependence of whether the request triggering the traffic has a direct bearing on user experience or service quality perception.

So for the exampLe of email, if a User sends an erriail, or physically triggers the request to checkwhether new email is awaiting delivery, the appLication sets the DSCP code point to indicate that the packets associated to the request are marked to indicate higher priority For background operations, e.g. synchronisation requests, or download of emails, which are not user requested, the AppLication wouLd be responsibLe for setting the DSCP of the associated IP traffic to indicate a lower priority The modem of the Smartphone would then be responsible (in line with the standards) to route the IP packets to different 3GPP bearers configured on the device by the network. The RAN (e.g. eNB) wouLd then in the normaL manner differentialLy allocate resource associated with the different 3GPP bearers -e.g. the DSCP packets marked with a higher priority wouLd be routed to a 3GPP bearerwith a higher priority OCI. The eNB aLlocates resources differentiaRy between customers based on traffic queues in the U Es, more resources wouLd be aLLocated to the customers with traffic waiting in the QCI of a higher priority OptionaLLy or additionaLly, the Optimisation PLatform in the MobiLe Network (indicated as MSP in the below diagram), wouLd compLement the uplink packet prioritisation by marking the associated downlink packets (associated with the uplink packets) with the same DSCP code point as that received in the uplink request. The P-GWwouLd route these packets to the 3GPP bearer associated with the DSCP marking and the eNB wouLd scheduLe the packets associated with the QCI of the bearer (or the eNB wouLd be responsibLe for scheduLing directLy on the DSCP marking itself) -in this way the downlink packets wouLd be differentially prioritised in the downLink.

See Figure 10.

In summary the present appLication proposes an application running on a mobiLe device (UE) impLements a method to mark IP packets with a priority based upon the 14') service and the impact on user experience of packet transmission. For example: I P packet priority can be increased by the application when a foreground task is triggered by a user (e.g. send an emaiL, online purchase) and, IP packet priority can be I"-. reduced by the application when a background task is triggered by the UE (e.g.

0 background synchronisation of contacts).

The present appLication aLso proposes a method to prioritise downlink data packets in tX') a telecommunications network based on parameters and/or status of a service and its reLated I P packets (a service is provided to a user equipment by transmitting the data forthe service in the form of data packets). Criteria for prioritisation based on parameters and/or status indude, for exampLe: The data volume transmitted to a terminal associated with a specific instance of a service The duration in which data has been transmitted to a terminaL associated with a specific instance of a service The required data rate of the service instance The measured performance of the connection between the terminaL and the connection The detection of TCP retransmission on the communication path between terminal and core network The estimated volume of data stored in the cLient buffer of the terminaL Assessment of direct impLication on customer experience or service perception Assessment of whether a packet is on the criticaL path for service deLivery and Assessment of whether a packet is used to downLoad other packets.

The present appLication aLso proposes a network node of a teLecommunications network which * Obtains an IP data packet fortransmission; * Identifies if the IP data packet for transmission is associated with a previousLy received I P data packet (e.g. a response to a request); * Identifies if the previousLy received IP data packet is marked with a specific priority; and, * Marks the IP data packet for transmission with the same priority as the previously received IPdata packet. IC) IC) r a

Claims (5)

1. CLAIMS1. A mobile telecommunications network comprising: a core network having content optimisation means operable to mark IP packets associated to a specific service, and a radio access network having radio means for wireless corn munication with terminals registered with the telecommunications network, wherein the radio access network is capable of scheduling traffic based on marking of the IP packets, wherein the content optimisation means is operable to differentially mark the IF packets of a specific service flow based on at least one of the following: -the data volume transmitted to a terminal associated with a specific instance of a service -the duration in which data has been transmitted to a terminal (\J associated with a specific instance of a service -the required data rate of the service instance (\J -the measured performance of the connection between the terminal and the connection -the detection of TGP retransmission on the communication path between terminal and core network -the estimated volume of data stored in the client buffer of the terminal -assessment of direct implication on customer experience or service perception -assessment of whether a packet is on the critical path for service delivery -assessment of whether a packet is used to download other packets.
2. 2. A mobile telecommunications network comprising: a core network having content optimisation means operable to mark IP packets associated to a specific service, and a radio access network having radio means for wireless communication with terminals registered with the telecommunications network, wherein the radio access network is capable of scheduling traffic based on marking of the IP packets, wherein the content optimisation means is operable to differentially mark the IP packets of a specific service flow based on aspects of the service provided.
3. 3. A system comprising a mobile telecommunications network and a terminal, the network comprising: a core network having means for configuration of multiple bearers between the core network and a terminal; and, (\J a radio access network having radio means for wireless communication with terminals registered with the telecommunications (\J network, the radio access network being capable of scheduling traffic based on a priority of configured bearers, wherein an application operating on the terminal is configured to differentially mark uplink packets based on an event that triggered an instance of a service (e.g. customer interaction) or on knowledge of customer perception of what triggered the service event.
4. 4. An application on a terminal, the terminal for use with a mobile telecommunications network, the application being configured to differentially mark uplink packets based on an event that triggered an instance of a service (e.g. customer interaction) or on knowledge of customer perception of what triggered the service event.
5. 5. A mobile telecommunications network comprising: a core network having content optimisation means operable to mark IP packets associated to a specific service, and a radio access network having radio means for wireless communication with terminals registered with the telecommunications network, wherein the radio access network is capable of scheduling traffic based on the priority of configured bearers, a terminal having application means for differentially marking packets based on knowledge of what triggered the service event wherein the content optimisation means is capable of marking downlink packets associated with an uplink packet with the same or similar marking as the received uplink packet. (4 r (4 r