WO2014149035A1

WO2014149035A1 - Reducing user palne congestion in a radio network

Info

Publication number: WO2014149035A1
Application number: PCT/US2013/032937
Authority: WO
Inventors: Devaki Chandramouli; Rainer Liebhart
Original assignee: Nokia Siemens Networks Oy
Priority date: 2013-03-19
Filing date: 2013-03-19
Publication date: 2014-09-25
Also published as: WO2014149035A8

Abstract

Methods and apparatuses are provided by which load on at least one cell is detected and load information indicating the load on the at least one cell is established. This load information is inserted in a signaling message destined directly or indirectly to a network element (e.g., a P- GW or a PCRF) capable of performing measures to adjust the load on the cell. This network element detects the load information and performs measures to adjust the load in the at least one cell based on the received load information.

Description

Reducing user plane congestion in a radio network

Field of the Invention

The present invention relates to an apparatus, a method and a computer program product for reducing user plane congestion in a radio network.

Related background Art

The following meanings for the abbreviations used in this specification apply:

AF Application Function

AS Application Server

BBERF Bearer Binding and Event Reporting Function

CGI Cell Global Identification

CN Core Network

eNB Enhanced NodeB

EPS Evolved Packet System

GERAN GSM/EDGE Radio Access Network

GPRS General packet radio service

HLR Home Location Register

H-PCRF Home PCRF

HPLMN Home Public Land Mobile Network

HSS Home Subscriber Server

IP-CAN Internet Protocol Connectivity Access Network

MME Mobility Management Entity

NAS Non-Access Stratum

PCEF Policy and Charging Enforcement Function

PCRF Policy and Charging Rules function PDN Packet data network

PDU Protocol Data Unit

P-GW Packet Data Network Gateway (also PGW)

QCI QoS Class Identifier

QoS Quality of Service

RAN Radio Access Network

S-GW Serving Gateway (also SGW)

SGSN Serving GPRS Support Node

S/P-GW Serving Packet Gateway

SPR Subscription Profile Repository

TDF Traffic Detection Function

UE User equipment

UTRAN Universal Terrestrial Radio Access Network

VPLMN Visited Public Land Mobile Network

V-PCRF PCRF in the VPLMN

Embodiments of the present invention relate to congestion in a radio network, for example in an EPS. EPS is the Evolved Packet System, the successor of GPRS (General Packet Radio System). It provides new radio interface and new packet core network functions for broadband wireless data access. Such EPS core network functions are the Mobility Management Entity (MME), Packet Data Network Gateway (PDN-GW) and Serving Gateway (S-GW).

Fig. 4 illustrates the Evolved Packet Core architecture. In short, within this architecture, a common packet domain Core Network is used for the Radio Access Networks (RAN) E-UTRAN, GERAN and UTRAN. This common Core Network provides GPRS services.

Fig. 5 illustrates an overall PCC architecture (roaming with home routed access) when SPR is used. The PCC architecture extends the architecture of an EPS core network as shown in Fig . 4, where the Policy and Charging Enforcement Function is a functional entity in the Gateway node implementing the IP access to the Packet Data Network.

It is noted that Fig . 4 can be found in TS 23.401, Fig .5 in TS 23.203 (e.g ., Fig . 5.1-3 in TS 23.203 V12.0.0 (2013-03)), so that it is referred to these documents for further information.

User plane congestion (UPCON) is one of the highest priority work items that is part of 3GPP release 12. Due to the surge in the mobile data traffic growth (i.e. due to smart phones) in the market, operators are faced with user plane congestion issues in the live network and this causes network instability. To be precise, operators are faced with issues due to user plane congestion in the radio network (i.e. in the eNB or in the backhaul link between eNB and S-GW i.e. on the Sl-U interface).

User plane congestion scenarios can be categorized as follows:

1. User plane congestion due to full use of cell capacity.

2. User plane congestion due to limited backhaul capacity (at the 3GPP RAN to EPC interface (i.e. Sl-U interface))

Current discussions in 3gpp separate between pro-active and re-active solutions for user plane congestion. Pro-active means that the core network provides information to RAN about ongoing sessions such as relative priority of traffic so that RAN takes measures when it detects congestion. Re-active means that RAN provides congestion information to CN so that CN take appropriate measures such as limiting the bandwidth for certain bearers or applications. Embodiments of the present invention are directed to a solution for the re-active solution. In order to take counter-measures against congestion in a cell, it is necessary to report load information to a corresponding network element such as a PCRF. However, such reports increase the load on the network. Summary of the Invention

Embodiments of the present invention address this situation and aim to overcome the above-described problem and to enable reporting of load information regarding a certain cell to a corresponding network element such as a PCRF without increasing the load on a network.

According to a first aspect of the present invention an apparatus is provided which comprises a connection unit configured to provide a connection to a network, and a processor configured to serve at least one cell, to detect load on the cell, to establish load information indicating the load on the at least one cell, to insert the load information in a signaling message destined directly or indirectly to a network element capable of performing measures to adjust the load on the cell, and to transmit the signaling message including the load information via the connection unit.

According to a second aspect of the present invention an apparatus is provided which comprises a connection unit configured to provide a connection to a network, and a processor configured to receive a first signaling message via the connection unit, including load information of at least one cell, to establish a second signaling message destined directly or indirectly to a network element capable of performing measures to adjust the load on the cell based on the received first signaling message, to insert the load information in the second signaling message, and to transmit the second signaling message including the load information via the connection unit.

According to a third aspect of the present invention an apparatus is provided which comprises a connection unit configured to provide a connection to a network, and a processor configured to receive a signaling message via the connection unit, to detect load information of a at least one cell included in the signaling message, and to perform measures to adjust the load in the at least one cell based on the received load information.

According to a fourth aspect of the present invention a method is provided which comprises

serving at least one cell,

detecting load on the cell,

establishing load information indicating the load on the at least one cell,

inserting the load information in a signaling message destined directly or indirectly to a network element capable of performing measures to adjust the load on the cell, and

transmitting the signaling message including the load information. According to a fifth aspect of the present invention a method is provided which comprises

receiving a first signaling message including load information of at least one cell,

establishing a second signaling message destined directly or indirectly to a network element capable of performing measures to adjust the load on the cell based on the received first signaling message,

inserting the load information in the second signaling message, and

transmitting the second signaling message including the load information.

According to a sixth aspect of the present invention a method is provided which comprises

receiving a signaling message via the connection unit,

to detect load information of a at least one cell included in the signaling message, and

to perform measures to adjust the load in the at least one cell based on the received load information. Modifications of the above aspects are defined in the dependent claims.

According to a seventh aspect of the present invention a computer program product is provided which comprises code means for performing a method according to any one of the above fourth to sixth aspects and/or their modifications when run on a processing means or module. The computer program product may be embodied on a computer- readable medium.

Brief Description of the Drawings

These and other objects, features, details and advantages will become more fully apparent from the following detailed description of embodiments of the present invention which is to be taken in conjunction with the appended drawings, in which :

Fig. 1 shows simplified structures of network elements according to an embodiment of the present invention,

Fig. 2 illustrates load information exchanged during mobility management procedure according to an embodiment of the present invention, Fig. 3 illustrates load information exchanged during session management procedure according to an embodiment of the present invention,

Fig. 4 shows an evolved packet core architecture, and Fig. 5 shows an overall PCC architecture. Detailed Description of embodiments

In the following, description will be made to embodiments of the present invention. It is to be understood, however, that the description is given by way of example only, and that the described embodiments are by no means to be understood as limiting the present invention thereto.

However, before explaining embodiments of the present invention in detail, the problem to be solved by the invention is described in more detail . That is, at first some possible solutions are described in the following, and after this the solution according to embodiments of the present invention is presented .

In particular, the following three possibilities of reporting load information from an eNB to a PCRF could be conceived :

1. Via OSS provided congestion control information :

The eNB reports load / congestion status information to the OSS and OSS provides this information directly or indirectly to the PCRF. Based on the load information or congestion status, PCRF can adjust the QoS allocated to bearers that are associated with the corresponding eNB.

The drawback with this solution is that OSS from different vendors deployed in operator's network may not be compatible thus interoperability becomes a challenge. It just implies that the output generated by OSS from 1 vendor (e.g . OSS managing the eNBs) may not follow a standard format thus may not be compatible to input read by network element (e.g . PCRF) provided by another vendor. Another drawback is that OSS cannot provide changes of load situation in RAN in real-time. 2. Introduction of NAF or a new functional entity between MME and PCRF

This solution entails introduction of a new network element to report congestion / overload information. The idea is that the eNB reports overload or congestion information to the MME which in turn reports it to the NAF and eventually to the PCRF. PCRF can adjust the QoS allocated to bearers that are associated with the corresponding eNB. The drawback with this approach is the introduction of new network element and also the additional dedicated signaling path to report overload from eNB -> MME -> NAF - > PCRF which introduces significant impact to products. It may not be fully justified to introduce a new interface and new functional element just for reporting load information / congestion status from RAN nodes towards PCRF. Furthermore, MME / NAF have to determine the appropriate PCRF for all the users connected to the given eNB and this will add to complexity in defining such a solution.

3. Introduction of new signaling path from eNB -> MME ->S-GW -> P-GW -> PCRF:

This solution entails introduction of a new signaling path but using the existing network elements and existing interfaces. The idea is that eNB reports overload or congestion information to the MME which in turn identifies the S-GW / P-GW for all the users connected to the corresponding eNB(s) and reports the congestion information to the PCRF. PCRF can adjust the QoS allocated to bearers that are associated with the corresponding eNB. The drawback with this approach is not just the introduction of additional dedicated signaling messages to report overload from eNB -> MME -> S-GW - > P-GW -> PCRF but also the reporting of overload information to a P-GW even if just a single user camping on the corresponding eNB is connected to a certain P-GW. This could generate high signaling and makes this solution very suboptimal. The amount of signaling generated due to the solution introduced for user plane congestion should also be considered carefully as the signaling traffic has also increased exponentially due to smart phones and this causes RAN and CN network overload / congestion and instability in the network. Hence, so far, there is no ideal solution that has been proposed to circumvent the issues mentioned above.

According to embodiments of the present invention, an alternative solution is provided to address user plane congestion in the radio network that does not have the limitations and complexity as discussed above. At the same time, the solution according to the embodiment enables PCRF to make QoS determination based on RAN load information / congestion status to help alleviate the congestion situation in the radio network. In particular, according to this embodiment, eNB load status information is added as part of existing signaling procedures that results e.g. in bearer establishment or modification .

In the following, a general embodiment of the present invention is described by referring to Fig . 1. In particular, Fig . 1 shows several elements involved in the procedure according to embodiments of the present invention. In more detail, Fig . 1 shows an eNB 1, an MME 2 and a PCRF 3. It is noted that in a bearer establishment and/or modification procedure further intermediate network elements (such as a S/P-GW) are involved . However, with respect to the reporting procedure, the basic function thereof would be the same as that of the MME in this respect, so that a further detailed description of such network elements is omitted in Fig. 1.

The eNB 1 is an example for an apparatus, e.g., an apparatus serving a cell or a plurality of cells, to which UEs may be attached, applying an embodiment of the present invention. The apparatus may also be only a part of the corresponding network element (e.g ., of the eNB). The eNB 1 comprises a processor 11 and a connection unit 12. The connection unit 12 is configured to provide a connection to a network. The processor 11 is configured to serve at least one cell, and is furthermore configured to detect load acting on the cell, to establish load information indicating the load acting on the at least one cell, to insert the load information in a signaling message destined directly or indirectly to a network element capable of performing measures to adjust the load on the cell (e.g., the PCRF 3), and to transmit the signaling message including the load information via the connection unit.

The MME 2 is an example for an apparatus, e.g. an intermediate network element through which load information from the eNB is forwarded to a PCRF. As mentioned above, the basic function with respect to the load information forwarding can be applied also to other intermediate network elements, such as a S/P-GW or the like that are relaying and processing signaling messages. The apparatus may also be only a part of the corresponding network element.

That is, when the MME 2 receives a signaling message (referred to as "first signaling message" in the following) including the load information, it inserts the load information into another signaling message (referred to as "second signaling message" in the following). Then, the MME 2 sends this second signaling message to the S/P-GW which can send a signaling message including load information to the PCRF 3. That is, similar as the MME 2, the S/P-GW takes the load information from the signaling message sent from the MME to the S/P-GW and inserts the load information in a signaling message to be sent to the PCRF.

In detail, the MME 2 comprises a processor 21 and a connection unit 22. The connection unit 22 is configured to provide a connection to a network. The processor 21 is configured to receive a first signaling message via the connection unit 22, which includes load information of at least one cell. The processor then establishes a second signaling message destined directly or indirectly to a network element (e.g., the PCRF 3) which is capable of performing measures to adjust the load on the cell based on the received first signaling message and inserts the load information in the second signaling message. The second signaling message including the load information is transmitted via the connection unit.

The PCRF 3 is an example for an apparatus which receives the load information and may apply operations to control the load in the cell based on the received load information, i.e., is an example for a network element (e.g., the PCRF 3) which is capable of performing measures to adjust the load on the cell. The apparatus may also be only a part of the corresponding network element. The PCRF 3 comprises a processor 31 and a connection unit 32. The connection unit 32 is configured to provide a connection to a network. The processor 31 is configured to receive a signaling message via the connection unit 32, to detect load information of at least one cell included in the signaling message, and to perform measures to adjust the load in the at least one cell based on the received load information.

Optionally, the eNB 1, the MME 2 and the PCRF 2 respectively may further comprise memories 13, 23 and 33 for storing data and programs, by means of which the respective processors 11, 21 and 31 may carry out their corresponding functions.

The signaling messages which are directly or indirectly destined to a network element such as the PCRF 3 are signaling messages, by which information is finally conveyed to the PCRF. That is, this includes a case in which the load information is sent indirectly via intermediate network elements (such as the MME or the S/P-GW), via different signaling messages between the different network elements. The signaling messages may be signaling messages which are related to a bearer establishment and/or modification procedure. In more detail, the signaling messages may be signaling messages which are used in a mobility management procedure and/or in a session management procedure. Further detailed examples for such signaling messages are described in the following by referring to Figs. 2 and 3.

Thus, according to embodiments of the present invention, the load information provided by the eNB 1 is inserted into an existing signaling message, which can be received by the PCRF 3. Hence, the PCRF 3 can receive the necessary load information in order to take counter-measures against a possible congestion. The MME 2 or the S/P-GW or another intermediate network element is able to forward the corresponding load information in existing signaling messages. Thus, there is no need for additional signaling in the network.

In the following, a more detailed embodiment of the present invention is described. In particular, according to an embodiment of the present invention, an alternative solution is provided to address user plane congestion in the radio network that does not have the limitations and complexity as in the prior art as described in the introductory section. At the same time, the solution according to the embodiment enables PCRF make QoS determination based on RAN load information / congestion status to help alleviate the congestion situation in the radio network. In particular, according to this embodiment, eNB load status information is added as part of existing signaling path that results in bearer establishment or modification procedure.

In the following, a procedure for exchanging load information is described. The eNB load information can be provided to the core network during the mobility management procedures - attach, TAU, Service Request procedure as part of bearer establishment and modifications. The eNB load information can also be provided to the core network as part of session management procedures - standalone PDN connectivity request, UE initiated bearer resource modification request. eNB can also provide load information in responses (acknowledgement or reject messages) to messages from MME or S-GW.

The load information can be inserted to all or only a subset of messages exchanged between eNB and MME/S-GW. This load information can be introduced as an optional information element in certain messages to avoid that all network nodes need to be updated.

Call flows shown in Figs. 2 and 3 described in the following illustrate how the eNB load status and validity time is provided by the RAN towards PCRF and how it is used by the PCRF to adjust the QoS for existing and new bearers being established based on the eNB load status.

The PCRF can use the load information for the corresponding cell identified by the provided E-UTRAN CGI (E-UTRAN Cell Global Identifier) and adjust the PCC rules appropriately for all the UE(s) connected to the given cell via the given PCRF. PCRF considers the load information to be valid for a certain period of time as indicated by validity time. PCRF can also use the load information from eNB to modify the bearer QoS for other UE(s) that are connected to the same cell identified by the E- UTRAN CGI. For instance, if the mobility management procedure is being initiated by a certain UE (referred to as UE-A in the following) through a certain eNB (referred to as eNB-X in the following), PCRF can avail the load information provided for eNB-X to adjust the bearer QoS for other devices connected to eNB-X. This approach helps the network to take proactive measures and reduce user plane congestion in the eNB periodically and proactively. PCRF can also take congestion information received from different UEs camping in the same cell into account before taking any actions. If the corresponding eNB is congested, PCRF can use this information to throttle traffic using a bearer with a certain QCI class of the congested cell. It can trigger "P-GW initiated bearer modification procedure with QoS update" for UE(s) that are already connected, to adjust the QoS and alleviate congestion. PCRF can also provide information about congested cells to Application Servers (AS) that have subscribed to this kind of information. Fig. 2 illustrates how load information is exchanged during mobility management procedure according to an embodiment of the present invention.

In Al, the UE sends an RRC Connection Complete message to the eNB, which includes an Attach request. In A2, the eNB forwards the initial UE message to the MME. This message includes the Attach request and a PDN connectivity request (for APN x), and includes the eNB load information, which comprises CGI load information and a validity time, as described above.

In A3, an authentication and subscription download procedure is carried out. In A4, the MME sends a Create Bearer Request, which includes the eNB load information as received in A2, to the S/P-GW. In A5, a PCEF initiated IP-CAN session establishment/modification follows, in which also the eNB load information is exchanged between the S/P-GW and the PCRF. After this, the S/P-GW sends a Create Bearer Response message to the MME, in order to complete the bearer creation procedure. In A6, the PCRF uses the load information received in A5 to adjust QoS information for users connected to the corresponding cells identified by CGI, i.e., which are served by the eNB.

The above procedure involves addition of new information elements to Initial UE message over Sl-AP (in A2), Create Bearer / Session Request messages over S5/S8 (in A4) and PCEF initiated IP-CAN Session Establishment / Modification messages over Gx (in A5).

Fig. 3 illustrates how load information is exchanged during session management procedures according to an embodiment of the present invention.

In Bl, the UE sends an UE Info Transfer message, including NAS PDU = PDN connectivity request to the eNB. In B2, the eNB sends an UL NAS Transport message to the MME. This message includes the NAS PDU = PDN connectivity request received in Bl, and furthermore includes the eNB load information, which comprises CGI load information and a validity time, similar as described above in connection with A2 in Fig . 2. In B3, the MME sends a Create Bearer Request, which includes the eNB load information as received in B2, to the S/P-GW. In B4, a PCEF initiated IP-CAN session establishment/modification follows, in which also the eNB load information is exchanged between the S/P-GW and the PCRF. After this, the S/P-GW sends a Create Bearer Response message to the MME. Similar as described above in connection with Fig. 2, the PCRF may now use the load information received in B4.

Thus, the procedure as described above by referring to Fig . 3 involves addition of new information elements to UL NAS Transport over Sl-AP (in B2), Create Bearer / Session Request messages over S5/S8 (in B3) and PCEF Initiated IP-CAN Session Establishment / Modification messages over Gx (in B4).

Referring back to the description of Fig . 1 as given above, it is noted that the messages in A2/B2 are examples for the signaling message or first signaling message sent from the eNB 1 to the MME 2. The messages in A2/A4 and B2/B3 are examples for the first signaling message, and the messages in A4/A5 and B3/B4 are examples for the second signaling message. The signaling messages in A5 and B4 are examples for the signaling message received by the network element capable of performing measures to adjust the load on the cell (e.g., the PCRF 3). In the following, the load information provided by the eNB is described in more detail . In particular, the eNB may define certain thresholds for peaks (e.g . T_high) and valleys (e.g . T|_0W)- If the user plane buffer crosses T_hig_h, then it may consider the current load as heavily loaded and if it falls below Tiow, then it may consider the current load to be lightly loaded. This should be carefully defined to ensure that the resources are not over utilized at the same time, it is not under-utilized and remain balanced across all eNBs.

The eNB may take into account the number of active UE(s) with data in the buffer and number of active UE(s) associated to a certain Sl-U interface while computing load information. The eNB could provide the current load information {Load = x%} and an indicator to show whether it is heavily loaded (i.e. > T_high), lightly loaded (i.e. < T|_0W) or in between i.e. stable state {high, medium, low} along with the validity time. Different congestion levels such as low, medium and high allows the core network (PCRF, PGW) to gradually downgrade QoS of certain services or bearers. Thus, even if there is no or not much signaling generated between RAN and CN that can carry load information, the CN can start at an early phase to adopt QoS for new or existing sessions (e.g . downgrade bandwidth, delay or drop packets). In order to indicate ^ληο congestion' the eNB can send an extra defined congestion level such as 'No^ongestion' or PCRF can also reset a received congestion level after validity timer has expired to ensure that the load information per eNB present in the PCRF is not obsolete when there is no signaling from a certain eNB.

Thus, according to embodiments of the present invention, the benefit is achieved that it is possible to exchange load information as part of existing signaling procedures. Thus, the solution according to embodiments of the present invention has minimal impact to eNB, MME, S-GW, P-GW and PCRF. It also enables proactive exchange of load information that helps the PCRF to adapt the QoS and policy rules accordingly or an AF to adapt the content to help alleviate RAN congestion. Since load information can be exchanged while establishing or modifying bearers, there is no need to define a new mechanism to discover the PCRF for a certain UE. Also, with this approach, MME does not have to report overload status to a P-GW / PCRF for a single user who is connected to a certain eNB using a new signaling message and it helps avoid introducing new signaling procedures to exchange load information.

It is noted that the embodiments and the present invention in general is not limited to the specific examples given above.

For example, in the embodiments described above in connection with Figs. 2 and 3, certain signaling messages were described . However, other messages are suitable, as long as they are existing signaling messages and directly or indirectly destined to a network element capable of performing measures to adjust the load on the cell (e.g . the P-GW, the PCRF or an AF). That is, the above-described re-use of existing signaling messages to send load information means that according to embodiments of the present invention, load information can be inserted in any signaling message used for general call processing, mobility management and session management between eNB, MME, P-GW/S-GW and PCRF.

Thus, according to several embodiments of the present invention, methods and apparatuses are provided by which load on at least one cell is detected and load information indicating the load on the at least one cell is established . This load information is inserted in a signaling message directly or indirectly destined to a network element (e.g., a P- GW or a PCRF) capable of performing measures to adjust the load on the cell. This network element detects the load information and performs measures to adjust the load in the at least one cell based on the received load information. According to another aspect of the present invention, an apparatus is provided which comprises

means for serving at least one cell,

means for detecting load on the cell,

means for establishing load information indicating the load on the at least one cell,

means for inserting the load information in a signaling message directly or indirectly destined to a network element capable of performing measures to adjust the load on the cell, and

means for transmitting the signaling message including the load information.

According to a further aspect of the present invention, an apparatus is provided which comprises

means for receiving a first signaling message including load information of at least one cell,

means for establishing a second signaling message directly or indirectly destined to a network element capable of performing measures to adjust the load on the cell based on the received first signaling message,

means for inserting the load information in the second signaling message, and

means for transmitting the second signaling message including the load information.

According to a still further aspect of the present invention, an apparatus is provided which comprises

means for receiving a signaling message via the connection unit, means for detecting load information of a at least one cell included in the signaling message, and

means for performing measures to adjust the load in the at least one cell based on the received load information. It is to be understood that any of the above modifications can be applied singly or in combination to the respective aspects and/or embodiments to which they refer, unless they are explicitly stated as excluding alternatives. For the purpose of the present invention as described herein above, it should be noted that

- an access technology via which signaling is transferred to and from a network element may be any technology by means of which a network element or sensor node can access another network element or node (e.g . via a base station or generally an access node). Any present or future technology, such as WLAN (Wireless Local Access Network), WiMAX (Worldwide Interoperability for Microwave Access), LTE, LTE-A, Bluetooth, Infrared, and the like may be used; although the above technologies are mostly wireless access technologies, e.g . in different radio spectra, access technology in the sense of the present invention implies also wired technologies, e.g . IP based access technologies like cable networks or fixed lines but also circuit switched access technologies; access technologies may be distinguishable in at least two categories or access domains such as packet switched and circuit switched, but the existence of more than two access domains does not impede the invention being applied thereto,

- usable communication networks, stations and transmission nodes may be or comprise any device, apparatus, unit or means by which a station, entity or other user equipment may connect to and/or utilize services offered by the access network; such services include, among others, data and/or (audio-) visual communication, data download etc.;

- a user equipment or communication network element (station) may be any device, apparatus, unit or means by which a system user or subscriber may experience services from an access network, such as a mobile phone or smart phone, a personal digital assistant PDA, or computer, or a device having a corresponding functionality, such as a modem chipset, a chip, a module etc., which can also be part of a UE or attached as a separate element to a UE, or the like;

- method steps likely to be implemented as software code portions and being run using a processor at a network element or terminal (as examples of devices, apparatuses and/or modules thereof, or as examples of entities including apparatuses and/or modules therefore), are software code independent and can be specified using any known or future developed programming language as long as the functionality defined by the method steps is preserved;

- generally, any method step is suitable to be implemented as software or by hardware without changing the idea of the invention in terms of the functionality implemented;

- method steps and/or devices, units or means likely to be implemented as hardware components at the above-defined apparatuses, or any module(s) thereof, (e.g ., devices carrying out the functions of the apparatuses according to the embodiments as described above, eNode-B etc. as described above) are hardware independent and can be implemented using any known or future developed hardware technology or any hybrids of these, such as MOS (Metal Oxide Semiconductor), CMOS (Complementary MOS), BiMOS (Bipolar MOS), BiCMOS (Bipolar CMOS), ECL (Emitter Coupled Logic), TTL (Transistor-Transistor Logic), etc., using for example ASIC (Application Specific IC (Integrated Circuit)) components, FPGA (Field-programmable Gate Arrays) components, CPLD (Complex Programmable Logic Device) components or DSP (Digital Signal Processor) components;

- devices, units or means (e.g. the above-defined apparatuses, or any one of their respective means) can be implemented as individual devices, units or means, but this does not exclude that they are implemented in a distributed fashion throughout the system, as long as the functionality of the device, unit or means is preserved; - an apparatus may be represented by a semiconductor chip, a chipset, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of an apparatus or module, instead of being hardware implemented, be implemented as software in a (software) module such as a computer program or a computer program product comprising executable software code portions for execution/being run on a processor;

- a device may be regarded as an apparatus or as an assembly of more than one apparatus, whether functionally in cooperation with each other or functionally independently of each other but in a same device housing, for example.

It is noted that the embodiments and examples described above are provided for illustrative purposes only and are in no way intended that the present invention is restricted thereto. Rather, it is the intention that all variations and modifications be included which fall within the spirit and scope of the appended claims.

Claims

1. An apparatus comprising

a connection unit configured to provide a connection to a network, and

a processor configured

to serve at least one cell,

to detect load on the cell,

to establish load information indicating the load on the at least one cell,

to insert the load information in a signaling message destined directly or indirectly to a network element capable of performing measures to adjust the load on the cell, and

to transmit the signaling message including the load information via the connection unit.

2. The apparatus according to claim 1, wherein

the network element capable of performing measures to adjust the load on the cell is a policy control network element and/or

the network element capable of performing measures to adjust the load on the cell is a packet data network gateway.

3. The apparatus according to claim 1 or 2, wherein

the signaling message is a signaling message which is related to a bearer establishment and/or modification procedure and/or which is used in general call processing, a mobility management procedure and/or in a session management procedure.

4. The apparatus according to any one of the claims 1 to 3, wherein the load information is included in an optional information field in the signaling message.

5. The apparatus according to any one of the claims 1 to 4, wherein the load information comprises a load status and a validity time.

6. The apparatus according to any one of the claims 1 to 5, wherein the processor is configured

to establish the load information by comparing the detected load with predefined load ranges, and to generate an indicator indicating in which load range the detected load falls, and

to establish and transmit, as the load information, the indicator and/or the detected load.

7. The apparatus according to claim 6, wherein the processor is configured

to define thresholds based on which the load ranges are defined.

8. An apparatus comprising

a connection unit configured to provide a connection to a network, and

a processor configured

to receive a first signaling message via the connection unit, including load information of at least one cell,

to establish a second signaling message destined directly or indirectly to a network element capable of performing measures to adjust the load on the cell,

to insert the load information in the second signaling message, and to transmit the second signaling message including the load information via the connection unit.

9. The apparatus according to claim 8, wherein

the network element capable of performing measures to adjust the load on the cell is a policy control network element, and/or

10. The apparatus according to claim 8 or 9, wherein the first and second signaling messages are signaling messages which are related to a bearer establishment and/or modification procedure and/or which are used in general call processing, a mobility management procedure and/or in a session management procedure.

11. The apparatus according to any one of the claims 8 to 10, wherein the load information is included in an optional information field in the first and/or second signaling message.

12. An apparatus comprising

a connection unit configured to provide a connection to a network, and

a processor configured

to receive a signaling message via the connection unit,

to perform measures to adjust the load in the at least one cell based on the received load information.

13. The apparatus according to claim 12, wherein

14. The apparatus according to claim 12 or 13, wherein the load information is included in an optional information field in the signaling message.

15. The apparatus according to any one of the claims 12 to 14, wherein the load information comprises a load status and a validity time.

16. The apparatus according to any one of the claims 12 to 15, wherein the load information comprises a detected load in the cell and/or an indicator, the indicator indicating in which load range of predefined load ranges the detected load falls.

17. The apparatus according to any one of the claims 12 to 16, wherein

the measures to adjust the load in the at least one cell based on the received load information includes adjusting quality of service for existing bearers and bearers to be established for the cell based on the load information and/or forwarding the received load information to a network control element capable of adjusting the content of traffic to be sent to the cell.

18. A method comprising

serving at least one cell,

detecting load on the cell,

establishing load information indicating the load on the at least one cell,

transmitting the signaling message including the load information.

19. The method according to claim 18, wherein

20. The method according to claim 18 or 19, wherein

21. The method according to any one of the claims 18 to 20, wherein the load information is included in an optional information field in the signaling message.

22. The method according to any one of the claims 18 to 21, wherein the load information comprises a load status and a validity time.

23. The method according to any one of the claims 18 to 22, further comprising

establishing the load information by comparing the detected load with predefined load ranges, and generating an indicator indicating in which load range the detected load falls, and

establishing and transmitting, as the load information, the indicator and/or the detected load.

24. The method according to claim 23, further comprising

defining thresholds based on which the load ranges are defined .

25. A method comprising

inserting the load information in the second signaling message, and

transmitting the second signaling message including the load information.

26. The method according to claim 25, wherein the network element capable of performing measures to adjust the load on the cell is a policy control network element and/or

27. The method according to claim 25 or 26, wherein

the first and second signaling messages are signaling messages which are related to a bearer establishment and/or modification procedure and/or which are used in general call processing, a mobility management procedure and/or in a session management procedure.

28. The method according to any one of the claims 25 to 27, wherein the load information is included in an optional information field in the first and/or second signaling message.

29. A method comprising

receiving a signaling message via the connection unit,

detecting load information of a at least one cell included in the signaling message, and

performing measures to adjust the load in the at least one cell based on the received load information.

30. The method according to claim 29, wherein

the signaling message is a signaling message which is related to a bearer establishment and/or modification procedure and/or which is used in a general call processing, mobility management procedure and/or in a session management procedure.

31. The method according to claim 29 or 30, wherein the load information is included in an optional information field in the signaling message.

32. The method according to any one of the claims 29 to 31, wherein the load information comprises a load status and a validity time.

33. The method according to any one of the claims 29 to 32, wherein the load information comprises a detected load in the cell and/or an indicator, the indicator indicating in which load range of predefined load ranges the detected load falls.

34. The method according to any one of the claims 29 to 33, wherein the measures to adjust the load in the at least one cell based on the received load information includes adjusting quality of service for existing bearers and bearers to be established for the cell based on the load information and/or forwarding the received load information to a network control element capable of adjusting the content of traffic to be sent to the cell.

35. A computer program product comprising code means for performing a method according to any one of claims 18 to 34 when run on a processing means or module.

36. The computer program product according to claim 35, wherein the computer program product is embodied on a computer-readable medium.