WO2010133255A1

WO2010133255A1 - Network components, entities, and methods configured for performing load balancing or for supporting the load balancing

Info

Publication number: WO2010133255A1
Application number: PCT/EP2009/056179
Authority: WO
Inventors: Jouni Korhonen
Original assignee: Nokia Siemens Networks Oy
Priority date: 2009-05-20
Filing date: 2009-05-20
Publication date: 2010-11-25

Abstract

The present invention refers to load balancing in a domain of a communications network, in which mobility management of mobile nodes is performed. The present invention concerns a network component configured to perform said load balancing and comprising: a selecting module configured to select a routing component from a set of routing components of a home agent entity in said domain, said routing components being configured to manage binding states of mobile nodes in said communications network; and a key assigning module configured to assign an uplink key to said routing component, said uplink key being configured to mark an uplink traffic in said domain. The present invention concerns a routing component, configured to be selected from said set of routing components by said network component and comprising a receiver configured to receive data from said network component; and a transmitter configured to route said data in said communications network.

Description

NETWORK COMPONENTS, ENTITIES, AND METHODS CONFIGURED FOR PERFORMING LOAD BALANCING OR FOR SUPPORTING THE LOAD BALANCING

FIELD OF THE INVENTION

The present invention relates to load balancing of connections used in domains of communications networks, in which the mobility management of mobile nodes is performed. Particularly, the present invention refers to a network compo- nent configured to perform said load balancing; a routing component selected by said network component when performing said load balancing; a network entity, configured as a home agent in said domain and involved in said load balancing; and corresponding methods, computer program products, and data carriers used for said load balancing.

BACKGROUND OF THE INVENTION

As mentioned above, the present invention addresses load bal- ancing of connections used in domains of communications networks, in which the mobility management of mobile nodes is performed. Usually, the mobility management is handled in said domains by use of accordingly configured protocols. The mobility management is one of major functions of communica- tions networks like GSM (Global System for Mobile communications) or UMTS (Universal Mobile Telecommunications System), for example. Mobility management comprises functions which allow mobile phones to work in a communications network. The aim of the mobility management is to track where the sub- scribers or mobile nodes respectively are, so that mobile phone services like calls, SMS (Short Message Service) etc., for example, can be delivered to them.

One example of such a domain is the Proxy Mobile IPv6 (PMIPvβ) domain. In the PMIPvβ domain, the mobility management of a mobile node is handled by use of a PMIPvβ protocol. The PMIPvβ domain comprises local mobility anchors and mobile access gateways as network entities which have security asso- ciations set up between each other. Mobile access gateways are authorized for sending Proxy Binding Updates on behalf of the mobile nodes to local mobility anchors.

A local mobility anchor (LMA) is a home agent for a mobile node in a domain as specified above (like the PMIPvβ domain, for example), i.e., a router on the home network of the mobile node which tunnels data for delivery to the mobile node when it is away from home, and maintains current location in- formation for the mobile node. The LMA is a topological anchor point for home network prefix (es) of the home network of the mobile node and is configured to manage the binding states of the mobile node.

The mobile access gateway (MAG) , in turn, is a function or entity (usually located on an access router) that manages the mobility-related signalling for a mobile node that is attached to its access link. MAG is responsible for tracking movements of a mobile node to and from the access link and for signalling the LMA of the mobile node.

When performing load balancing of connections used in domains of communications networks, in which the mobility management of mobile nodes is performed, such as PMIPvβ domain, for ex- ample, the processes concerning the load balancing have several dependencies on entities, components, and/or functions of these domains.

When considering the PMIPvβ domain, the load balancing of PMIPvβ connections inside a local mobility anchor (LMA) depends on several factors, entities, components, and/or functions like the following, for example:

domain name system (DNS) based round robin solutions used for load balancing; internet protocol (IP) routings to get the incoming IP packets to a correct service blade (SB) inside a PMIPvβ gateway;

- modifying and/or creating of new security associations between a MAG and a LMA;

changes on the existing PMIPvβ protocol specifications (e.g. , RFC 5213) ;

used MAG to LMA security solutions; and/or

control plane and/or user plane functions.

Thus, here is still a need for improved load balancing in domains of communications networks, in which the mobility management of mobile nodes is performed, such as PMIPvβ domain, for example, which should be more independent on entities, components, and/or functions of these domains.

SUMMARY OF THE INVENTION

Object of the present invention is improving of load balancing in domains of communications networks, in which the mo- bility management of mobile nodes is performed.

This object is achieved by a network component comprising features according to claim 1, a method comprising features according to claim 8, a computer program product comprising features according to claim 9, a data carrier comprising features according to claim 10, a routing component comprising features according to claim 11, a method comprising features according to claim 16, a computer program product comprising features according to claim 17, a data carrier comprising features according to claim 18, and a network entity comprising features according to claim 20. Further embodiments of the present invention are provided with the corresponding dependent claims.

The object of the present invention is achieved by a network component, said component being configured to perform load balancing in a domain of a communications network, in which mobility management of mobile nodes is performed, and comprising :

- a selecting module configured to select a routing component from a set of routing components of a home agent entity in said domain, said routing components being configured to manage binding states of mobile nodes in said communications network; and

- a key assigning module configured to assign an uplink key to said routing component, said uplink key being configured to mark an uplink traffic in said domain belonging to a (specific) mobility session in said communications network.

By use of the network component a load balancing in said do- main is achieved which is independent on further entities, components, and/or functions of the domain. Here, the load balancing is performed with regard to the uplink traffic and by use of uplink keys marking the uplink traffic in the corresponding domain.

Once the uplink key has been assigned, also the routing component or service blade, as explained bellow, is selected for a certain or specific mobility session. Therefore, the present invention allows that beside the uplink traffic also the downlink traffic goes through the selected routing component or service blade. As the selected routing component or service blade is located in LMA, according to an embodiment of the present invention, both the downlink traffic and the uplink traffic will go through the selected routing component or service blade of that LMA the uplink key points at. Thus, also when performed with regard to uplink keys, the load balancing according to the present invention concerns both the uplink traffic and the downlink traffic. According to an embodiment of the present invention, said network component comprises a receiver configured to receive a proxy update binding message, wherein said selecting module is configured to select said routing component after receiving of said proxy update binding message by said receiver. In this way, the network component configured to manage load balancing in said domain has the capability of establishing uplink connections in the domain. Thus, a more effective load balancing is enabled as already the establishing of the uplink traffic (performed by the network component configured to manage load balancing in said domain) is performed by considering conditions for a load balanced uplink traffic.

According to an embodiment of the present invention, for downlink traffic coming from an external communications network (e.g. internet) towards to LMA, the traffic is routed to that LMA service blade the assigned key points at. This is performed within the scope of a conventional routing like IP routing, for example, as each routing component or service blade of the LMA has their own IP on the external network side. Alternatively the LMA may have some stateful packet inspection logic that forwards arriving downlink traffic to a correct service blade, e.g., based on the MN prefix, for ex- ample.

According to an embodiment of the present invention, the network component comprises a transmitter configured to transmit a proxy binding acknowledgement comprising said uplink key.

According to an embodiment of the present invention, said network component comprises a key determining module configured to determine said uplink key to mark said uplink traffic. According to a further embodiment of the present inven- tion, the key determining module is configured to determine said uplink key in a dynamic way, e.g., by selecting the uplink key from a set or pool of uplink keys. Thus, a flexible and sovereign assignment of uplink key is enabled by the present invention.

According to an embodiment of the present invention, said network component comprises a data managing module configured to:

- receive data with said uplink key; and

- provide said data to said routing component, assigned to said uplink key, for routing said data in said communications network.

In this way, a sovereign and load balanced handling of uplink and downlink traffic in said domain is enabled which is independent on further components, elements, functionalities, and/or factors of said domain.

According to an embodiment of the present invention, said network component is comprised in said home agent entity.

According to a further embodiment of the present invention, said home agent entity is a local mobility anchor.

The object of the present invention is achieved also by a method for balancing of loads in a domain of a communications network, in which mobility management of mobile nodes is performed. In particular, said method comprises balancing of loads in a domain of a communications network, in which mobility management of mobile nodes is performed, by a network component, wherein said balancing of loads comprises: - selecting of a routing component from a set of routing components of a home agent entity in said domain, said routing components being configured for managing of binding states of mobile nodes in said communications network; and

- assigning of an uplink key to said routing component, said uplink key being configured to mark an uplink traffic in said domain belonging to a (specific) mobility session in said communications network. Here, said network component corresponds to the network component sketched above and explained in more detail below. In particular, the method is configured to perform the actions of said network component, i.e., of the corresponding modules of said network component, within the scope of load balancing in said domain.

The object of the present invention is achieved also by a computer program product comprising a code, the code being configured to implement and/or perform said method.

According to an embodiment of the present invention, the code is embodied on a data carrier. According to a further embodiment of the present invention, the computer program product is configured to perform said method when the computer program product is executed by a processing unit like a processor, for example. Here, the processing unit can be a module of said network component sketched above and explained in more detail below.

Moreover, the object of the present invention is achieved by a data carrier comprising said computer program product.

Further, the object of the present invention is achieved by a routing component, said routing component being configured to be selected from a set of routing components by a network component when performing load balancing in a domain of a communications network, in which mobility management of mobile nodes is performed, wherein: - said set of routing components is comprised in a home agent entity in said domain;

- said routing components are configured for managing of binding states of mobile nodes in said communications network; and - said network component is configured to perform said load balancing; said routing component comprising: - a receiver configured to receive data from said network component; and

- a transmitter configured to route said data in said communications network.

Here, the routing component is selected by the network component sketched above and explained in more detail below when performing load balancing according to the present invention. Here, the routing component is configured to be assigned to a specific or particular uplink traffic of mobility session respectively by the network component, wherein the network component performs this assignment by assigning an uplink key to said routing component, said uplink key being configured to mark the uplink traffic in said domain belonging to a spe- cific mobility session in said communications network.

Thus, a load balancing in said domain is enabled which is independent on further components, elements, functions, and/or factors in said domain.

According to an embodiment of the present invention, said routing component comprises a key determining module configured to determine an uplink key, said uplink key being configured to mark an uplink traffic in said domain belonging to a (specific) mobility session in said communications network.

Thus, a more effective load balancing is enabled as already the establishing of the uplink traffic is performed by considering conditions for a load balanced uplink traffic and downlink traffic accordingly.

According to a further embodiment of the present invention, said key determining module is configured to determine said uplink key if said data received by said receiver is a proxy update binding message.

According to an embodiment of the present invention, said routing component comprises a transmitter configured to transmit a proxy binding acknowledgement, comprising said uplink key, to said network component.

The object of the present invention is achieved also by a method, said method being implemented by a routing component, wherein said routing component is configured to be selected from a set of routing components by a network component when performing load balancing in a domain of a communications network, in which mobility management of mobile nodes is performed, wherein:

- said set of routing components is comprised in a home agent entity in said domain;

- said routing components are configured for managing of binding states of mobile nodes in said communications network; and

- said network component is configured to perform said load balancing; said method comprising:

- receiving of data from said network component by said routing component, selected from said set of routing components; and - routing said data in said communications network.

Here, the method is performed by the routing component sketched above and explained in more detail below. In particular, the method is configured to perform the actions of the routing component or its modules respectively within the scope of providing a load balanced uplink traffic according to the present invention.

Further, the object of the present invention is achieved by a computer program product comprising a code, the code being configured to implement and/or perform said method. According to an embodiment of the present invention, the code is embodied on a data carrier. According to a further embodiment of the present invention, the computer program product is configured to perform said method when the computer pro- gram product is executed by a processing unit like a processor, for example. Here, the processing unit can be a module of said routing component.

Further, the object of the present invention is achieved by a network entity, wherein:

- said network entity is configured as a home agent in a do- main of a communications network, in which mobility management of mobile nodes is performed; and

- said network entity comprises a set of routing components, wherein at least one of said routing components is a routing component sketched above and explained in more detail below.

According to an embodiment of the present invention, said network entity comprises a network component which corresponds to the network component sketched above and explained in more detail below.

According to a further embodiment of the present invention, said network entity is a local mobility anchor.

Thus, the present invention allows a more sovereign load bal- ancing of uplink traffic and downlink traffic in domains of communications networks, in which the mobility management of mobile nodes is performed, in an efficient way. The load balancing according to the present invention can be implemented flexibly with regard to several existing standard specifica- tions. Here, no essential changes of components, entities, or functionalities within said domains are mandatory necessary.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more clearly understood from the following description of the preferred embodiments of the invention read in conjunction with the attached drawings, in which:

Fig. 1 shows implementation of the present invention according to an embodiment of the present invention;

Fig. 2 shows uplink key based load balancing according to an embodiment of the present invention;

Fig. 3 shows uplink key based load balancing according to a further embodiment of the present invention; and

Fig. 4 shows handling of uplink traffic according to an embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In following the embodiments of the present invention are provided exemplary with regard to PMIPvβ domain as a domain of a communications network, in which mobility management of mobile nodes is performed. Here, it has to be noted that the present invention is not restricted to application in the PMIPvβ domain only and that the present invention can be used accordingly also in further domains of communications networks, in which mobility management of mobile nodes is per- formed.

Fig. 1 shows implementation of the present invention according to an embodiment of the present invention.

Here, the domain of communications networks, in which mobility management of mobile nodes is performed, is the PMIPvβ domain 1. Between a LMA 15 and a MAG 10 a tunnelled traffic is established, wherein according to the present embodiment the PMIPvβ tunnel is used. For marking of this tunnelled traffic, downlink GRE (Generic Routing Encapsulation) keys are used for the downlink traffic and uplink GRE keys are used for the uplink traffic. In particular, according to the present embodiment GRE (Generic Routing Encapsulation) keys are used as specified, for example, in A. Muhanna et al . "GRE key option for proxy mobile IPv6", draft-ietf-netlmm-grekey- option-06.txt, February 24, 2009. The downlink and uplink GRE keys are used for marking the downlink and uplink traffic that belong to a specific mobility session.

In particular, a downlink GRE key is assigned by the MAG 10 and is used by the LMA to mark the downlink traffic which belongs to a specific mobility session.

An uplink GRE key, in turn, is assigned by the LMA 15 and is used by the MAG 10 to mark the uplink traffic which belongs to a specific mobility session, wherein the uplink traffic is a tunnel 14 between the MAG 10 and the LMA 15, heading to- wards the LMA 15 and tunnelled at the MAG.

According to the present embodiment, in line with the PMIPvβ specification, the term mobility session refers to creation or existence of state associated with the mobile node's mo- bility binding on the LMA 15 and on the serving MAG 10.

When considering Fig. 1, an uplink GRE key "uplink-key-1" marks an uplink flow 11, an uplink GRE key "uplink-key-2" marks an uplink flow 12, and an uplink GRE key "uplink-key-3" marks an uplink flow 13, wherein the uplink flows 11, 12, 13 are tunnelled through the tunnel 14, which is the PMIPvβ tunnel according to the present embodiment. In following, the uplink flows 11, 12, 13 are referred to also as mobility sessions or uplink traffics 11, 12, 13.

When a an uplink flow 11, 12, 13 is established between the MAG 10 and the LMA 15, the GRE load balancer 16 selects a service blade 171, 172, 173 from a set 17 of service blades 171, 172, 173 and assigns to the corresponding traffic or uplink flow 11, 12, 13 to be established. Further, the corresponding uplink GRE key created dynamically is assigned to the corresponding traffic or uplink flow 11, 12, 13 by the GRE load balancer 16 too. In particular, the corresponding binding of an uplink GRE key and of a service blade 171, 172, 173 to a corresponding traffic 11, 12, 13 is performed by a selecting module 161 and a key assigning module 162 of the GRE load balancer 16. The selecting module 161 is configured to select a service blade 171, 172, 173 from the set 17, and the key assigning module 162 is configured to assign the uplink GRE key to the selected service blade 171, 172, 173.

Then, in following, all future uplink traffic 11, 12, 13 that enters the LMA 15 gets forwarded by the GRE load balancer 16 to the selected service blade 171, 172, 173 based on the assigned uplink GRE key. This is pointed out in Fig. 1 by the corresponding arrows 11, 12, 13. The MAG 10 transmits data to the LMA 15 by use of a corresponding uplink GRE key on the corresponding uplink traffic or traffic flow 11, 12, 13, marked by the uplink GRE key. Thus, each data is transmitted via the corresponding uplink traffic flow 11, 12, 13 by the MAG 10 and is marked by the corresponding uplink GRE key.

Here, the MAG 10 sees the LMA 15 as one IP (internet protocol) address, therefore, only one security association (SA) is established between the MAG 10 and the LMA 15; although, actually, the LMA 15 represents or comprises a set of 17 independent sub LMAs 171, 172, 173, which are the above men- tioned service blades. Here, each of the service blades 171,

172, 173 is configured as a LMA. In particular, the service blades 171, 172, 173 are configured to manage binding states of mobile nodes in communications network. The service blades 171, 172, 173 are configured to handle the user plane and the control plane of the domain, in which mobility management of mobile nodes is performed, according to the present embodiment - the MPIPv6 domain. Thus, the MAG 10 uses only the (IP) address of the LMA 15 and, due to uplink key balancing per- formed by the GRE load balancer 16, does not need to care about the actual address of the actual (sub-) LMA or service blade respectively 171, 172, 173 routing the corresponding data in the network.

For forwarding of the uplink traffic 11, 12, 13 to the corresponding service blade 171, 172, 173, the GRE load balancer 16 comprises, according to the present embodiment, a data managing module 163, which is configured to receive data, transmitted or provided by the MAG 10, by use of the uplink traffic 11, 12, 13 marked by the corresponding uplink GRE key, and to provide 11, 12, 13 this data to the service blade or sub LMA respectively 171, 172, 173, to which the corresponding uplink GRE key has been assigned. Here, the data managing module 163 peeks the corresponding uplink GRE key when receiving the data and uses it for selecting the corresponding service blade or sub LMA respectively 171, 172, 173.

According to the present embodiment, the uplink GRE key may be reassigned during the lifetime of the mobility session. In such a case, as consequence, either a signalling with regard to the reassigned GRE key back to the MAG 10 can be done or the mobility session can be moved to another service blade or sub LMA respectively 171, 172, 173 of the LMA 15. In the lat- ter case, the selecting module 161 of the GRE load balancer is configured to select another service blade or sub LMA respectively 171, 172, 173, and the key assigning module 162 is configured to assign the uplink GRE key to the reselected service blade or sub LMA respectively 171, 172, 173.

As shown in Fig. 1, the GRE load balancer 16 is comprised in the LMA 15. However, the present invention is not restricted to this arrangement only. According to a further embodiment of the present invention, the GRE load balancer 16 is pro- vided as a separate entity, which is connected to the MAG 10 to receive data via the uplink traffic flows 11, 12, 13, each of them marked by a certain uplink GRE key, and which is connected to the LMA 15 to provide said data to the correspond- ing service blades 171, 172, 173 of the LMA 15 or sub LMAs

171, 172, 173 of the LMA 15 respectively.

Fig. 2 shows uplink key based load balancing according to an embodiment of the present invention.

According to the present embodiment the GRE load balancer 16 comprises also a receiver 164 configured for receiving data from the MAG 10, a transmitter 165 for transmitting data to the MAG 10, and a key determining module 166 configured to determine uplink keys to mark the uplink traffic 11, 12, 13 and to be assigned to the corresponding service blades 171,

172, 173 of the LMA 15 or sub LMAs 171, 172, 173 of the LMA

15 respectively.

When establishing an uplink traffic 11, 12, 13 to be marked by an uplink GRE key, according to the present embodiment, in step 21 the MAG 10 transmits a proxy binding update (PBU) message to the LMA 15. The transmission 21 of the PBU message can be performed as described, e.g., in A. Muhanna et al . "GRE key option for proxy mobile IPv6", draft-ietf-netlmm- grekey-option-06.txt, February 24, 2009.

The LMA 15 receives the PUB message and provides in step 22 this message to the GRE load balancer 16. According to the present embodiment, the receiver 164 of the GRE load balancer

16 receives the PBU message and provides it to the key determining module 166 of the GRE load balancer 16. In step 23, the key determining module 166 determines dynamically an up- link GRE key for the uplink traffic 11, 12, 13 to be established. Here, the key determining module 166 can determine the uplink GRE key, e.g., by selecting the key from a GRE key space or a GRE key pool, which can be accessed by the LMA 15, the GRE load balancer 16, and/or the MAG 10. As mobility ses- sions or uplink traffic is done by use of one flow 11, 12, 13 at time, in step 23 assigning of one uplink GRE key per mobility session only is performed according to the present embodiment . Further, the key determining module 166 of the GRE load balancer 16 provides the determined uplink GRE key to the selecting module 161 of the GRE load balancer 16. In step 24, the selecting module 161 selects then a service blade 171, 172, 173 of the LMA 15 or sub LMAs 171, 172, 173 of the LMA 15. According to the present embodiment, the service blade or sub LMA 171 respectively is selected. The selecting module 161 can select, for example, such a service blade or sub LMA 171, 172, 173 for the uplink traffic 11, 12, 13 which has the most free resources, e.g., the most free resources for handling uplink traffic in the PMIPvδ domain 1. Here, several criteria can be applied when selecting an appropriate service blade or sub LMA 171, 172, 173 for an uplink traffic 11, 12, 13 to be established. Subsequently, the determined uplink GRE key and information about the selected service blade or sub LMA 171 is provided by the selecting module 161 to the key assigning module 162 of the GRE load balancer 16. In step 25, the key assigning module 162 assigns then the determined up- link GRE key to the selected service blade or sub LMA 171. In this way, the determined uplink GRE key and the selected service blade or sub LMA 171 are assigned or bound to the uplink traffic 11, 12, 13 to be established between the MAG 10 and the LMA 15.

Finally, in step 26, the transmitter 165 of the GRE load balancer 16 transmits a proxy binding acknowledgement (PBA) message, comprising the determined uplink GRE key, to the MAG 10, wherein the PBA message can be transmitted via the LMA 15. In the latter case, the transmitter 165 is configured to transmit the PBA message to the LMA 15, which in turn transmits the PBA message to the MAG 10. This providing of the PBA message to the MAG 10 can be performed as described in A. Mu- hanna et al . "GRE key option for proxy mobile IPv6", draft- ietf-netlmm-grekey-option-06.txt, February 24, 2009, for example . Fig. 3 shows uplink key based load balancing according to a further embodiment of the present invention.

According to the present embodiment the uplink GRE keys are determined by the service blade or sub LMA 171 of the LMA 15 selected by the GRE load balancer 16.

According to the present embodiment, when establishing an uplink traffic 11, 12, 13 to be marked by an uplink GRE key, in step 31 the MAG 10 transmits a proxy binding update (PUB) message to the LMA 15. Also here, the transmission 31 of the PUB message can be performed as described, e.g., in A. Mu- hanna et al . "GRE key option for proxy mobile IPv6", draft- ietf-netlmm-grekey-option-06.txt, February 24, 2009. Accord- ing to the present embodiment, each setting up of the uplink traffic 11, 12, 13 requires a separate PBU/PBA exchange.

The LMA 15 receives the PBU message and provides this message in step 32 to the GRE load balancer 16. According to the pre- sent embodiment, the receiver 164 of the GRE load balancer 16 receives the PBU message and provides it to the selecting module 161 of the GRE load balancer 16. In step 33, the selecting module 161 selects then a service blade 171, 172, 173 of the LMA 15 or sub LMAs 171, 172, 173 of the LMA 15. Ac- cording to the present embodiment, the service blade or sub LMA 171 respectively is selected. The selecting module 161 can select, for example, such a service blade or sub LMA 171, 172, 173 for the uplink traffic 11, 12, 13 which has the most free resources, e.g., the most free resources for handling uplink traffic in the PMIPvδ domain 1. Here, several criteria can be applied when selecting an appropriate service blade or sub LMA 171, 172, 173 for an uplink traffic 11, 12, 13 to be established.

Then, in step 34, the selecting module 161 provides the PBU message to the selected service blade or sub LMA 171 of the LMA 15. According to the present embodiment, each of service blades or sub LMAs 171, 172, 173 and in particular the se- lected service blade or sub LMA 171 comprises a receiver 1711, a transmitter 1712, and a key determining module 1713. The receiver 1711 is configured to receive data from the GRE load balancer 16. Presently, the receiver 1711 receives the PBU message transmitted originally by the MAG 10. The receiver 1711 provides then the PUB message to the key determining module 1713 of the selected service blade or sub LMA 171. In step 35, the key determining module 1713 determines dynamically an uplink GRE key for the uplink traffic 11, 12, 13 to be established. Here, the key determining module 1713 can determine the uplink GRE key, e.g., by selecting the key from a GRE key space or a GRE key pool, which can be accessed by the LMA 15, the service blades or sub LMAs 171, 172, 173, and/or the MAG 10.

Further, the key determining module 1713 of the selected service blade or sub LMA 171 provides the determined uplink GRE key to the transmitter 1712 of the of the selected service blade or sub LMA 171. The transmitter 1712 transmits then in step 36 the determined uplink GRE key to the GRE load balancer 16. In particular, the transmitter 1712 transmits a proxy binding acknowledgement (PBA) message, comprising the determined uplink GRE key to the GRE load balancer 16.

The receiver 164 of the GRE load balancer 16 receives the PBA message comprising the determined uplink GRE key and provides it to the key assigning module 162 of the GRE load balancer 16.

In step 37, the key assigning module 162 assigns then the determined uplink GRE key to the selected service blade or sub LMA 171. In this way, the determined uplink GRE key and the selected service blade or sub LMA 171 are assigned or bound to the uplink traffic 11, 12, 13 to be established between the MAG 10 and the LMA 15.

Finally, in step 38, the transmitter 165 of the GRE load balancer 16 transmits the PBA message, comprising the determined uplink GRE key, to the MAG 10, wherein the PBA message can be transmitted via the LMA 15. In this case, the transmitter 165 is configured to transmit the PBA message to the LMA 15, which in turn transmits the PBA message to the MAG 10. This providing of the PBA message to the MAG 10 can be performed as described in A. Muhanna et al . "GRE key option for proxy mobile IPv6", draft-ietf-netlmm-grekey-option-06.txt, February 24, 2009, for example.

Fig. 4 shows handling of uplink traffic in a domain of a communications network, in which mobility management of mobile nodes is performed, according to an embodiment of the present invention .

The present embodiment joins the embodiments provided above. A precondition for this embodiment is that the uplink traffic

11, 12, 13 has already been established between the MAG 10 and the LMA 15. Thus, the present embodiment refers to handling of an uplink traffic 11, 12, 13 established between the MAG 10 and the LMA 15.

The MAG 10 transmits data by use of the uplink traffic 11,

12, 13 to the LMA 15 in step 41. Here, the MAG 10 can transmit the data by use of an address of the LMA 15 like an IP address, for example. Here, only one security association is provided between the MAG 10 and the LMA 15, and it is not mandatory that the MAG 10 has information concerning the service blades or sub LMAs 171, 172, 173 of the LMA 15 actually handling the uplink traffic as home agents in the domain for performing mobility management of mobile nodes, here, the PMIPv6 domain.

In step 42, the LMA 15 provides this data to the GRE load balancer 16. The receiver 164 of the GRE load balancer 16 re- ceives the data and provides it to the data managing module 163 of the GRE load balancer. The data managing module 163 peeks the uplink GRE key, provided by the LMA 15 with the data, from the data received. Here, the data managing module 163 has the knowledge of associated uplink GRE keys and service blades or sub LMAs 171, 172, 173. Thus, the data managing module 163 is aware of uplink GRE keys and service blades or sub LMAs 171, 172, 173 associated to the corresponding up- link traffic 11, 12, 13. In step 43, the data managing module 163 detects the service blade or sub LMA 171 associated to the uplink GRE key provided with the data. Then, in step 44, the data managing module 163 provides the data to the detected service blade or sub LMA 171, associated to said up- link GRE key.

The corresponding service blade or sub LMA 171 or the receiver 1711 of the corresponding service blade or sub LMA 171 respectively receives the data. Then, in step 45, the service blade or sub LMA 171 or the transmitter 1711 of the service blade or sub LMA 171 respectively routes this data in the communications network in accordance with the destination of the data.

As already mentioned above, the uplink GRE keys can be reassigned during the lifetime of the mobility session. In this case, a GRE key signalling as exemplary shown in Fig. 2 and Fig. 3 can be performed. However, alternatively, the reassigning of the uplink GRE keys can be performed also inter- nally. In this alternative case, the selecting module 161 of the GRE load balancer 16 is configured to select another service blade or sub LMA 171, 172, 173 of the LMA 15 for the corresponding uplink 11, 12, 13; and the key assigning module 162, in turn, is configured to assign the uplink GRE key as- signed to the corresponding uplink 11, 12, 13 to the rese- lected service blade or sub LMA 171, 172, 173. Thus, the corresponding uplink 11, 12, 13 still has the previously determined uplink GRE key and is assigned to another service blade or sub LMA 171, 172, 173, having more free resources, for ex- ample.

Further, this reassigning procedure can be performed also in combination with anew determination of a uplink GRE key. In this case, the GRE key signalling as exemplary shown in Fig. 2 and Fig. 3 is performed additionally.

The present invention is explained by use of embodiments re- ferring in particular to the PMIPvβ GRE keying and tunnelling. However, the present invention can be implemented accordingly also in further domains of communications networks, in which mobility management of mobile nodes is performed.

As shown in the embodiments of the present invention, the GRE load balancer 16 is a network entity or network component that shows as the LMA 15 towards MAGs 10. The GRE load balancer 16 peeks into the PMIPv6 tunnelled traffic 11, 12, 13, finds the GRE key and does the internal forwarding decision to the right service blade or sub LMA 171, 172, 173 based on the GRE key. The GRE load balancer 16 may also be the entity that terminates the PMIPv6 tunnel and decapsulates it off. Alternatively, the GRE load balancer 16 may just forward traffic and in that case the corresponding service blade or sub LMA 171, 172, 173 does all PMIPv6 and GRE tunnel decapsulation .

If the user plane traffic between the MAG 10 and the LMA 15 is IP security protected with confidentially protection then the GRE load balancer 16 is configured to decapsulate the IP security tunnel.

Further, according to an embodiment of the present invention, the determining of GRE keys and/or selecting of service blades or sub LMAs 171, 172, 173 can be based on a number of heuristics, such as calculating a hash of the MN-ID found in the PBU, for example. Here, many ways of determining the GRE keys and/or selecting of service blades or sub LMAs 171, 172, 173 are possible according to the present invention.

Additionally, if security associations between MAGs 10 and LMAs 15 are created dynamically so that each traffic flow 11, 12, 13 or mobility session respectively requires a new IP sec security association, then the encapsulating security protocol (ESP) security parameter index (SPI) of the created CHILD security associations can be used in a same way as GRE keys when implementing the present invention. Thus, the present invention allows a variety of possibilities of implementation of the present invention.

Thus, the present invention refers to load balancing in a domain of a communications network, in which mobility manage- ment of mobile nodes is performed. In particular, the present invention concerns a network component 16 configured to perform said load balancing and comprising: a selecting module 161 configured to select a routing component 171, 172, 173 from a set 17 of routing components of a home agent entity 15 in said domain 1, said routing components 171, 172, 173 being configured to manage binding states of mobile nodes in said communications network; and a key assigning module 162 configured to assign an uplink key to said routing component

171, 172, 173, said uplink key being configured to mark an uplink traffic 11, 12, 13 in said domain 1. Further, the present invention concerns a routing component 171, 172, 173, configured to be selected from said set 17 of routing components by said network component 16 and comprising a receiver 1711 configured to receive data from said network component 16; and a transmitter 1712 configured to route said data in said communications network. Here, the routing component 171,

172, 173 is configured to be assigned by the network component 16 to a particular uplink traffic 11, 12, 13, i.e., to be assigned to a corresponding uplink key marking the uplink traffic 11, 12, 13. In particular, the network component 13 assigns a corresponding uplink key to the routing component 171, 171, 173.

By use of the present invention a load balancing of connec- tions used in domains of communications networks, in which the mobility management of mobile nodes is performed, is enabled which does not depend on external entities such as DNS for load balancing, for example. Further, by use of the present invention the LMA may switch its service blades or sub LMAs internally by changing the internal GRE based forwarding. Therefore, a signalling of a new GRE key to the MAG during the next PBU/PBA message exchange can be performed. Alternatively, this switching can be handled also completely internally without external change of any information.

Moreover, the present invention allows performing of signalling load balancing decision to the LMA inband in a PBA message. Thus, no additional signalling or roundtrips are required.

Furthermore, when implementing the present invention, no changes to existing standard specifications are required. Thus, the present invention can be implemented efficiently and effectively with regard to all appropriate existing standard specifications.

Additionally, no redirecting of PMIPvβ tunnels at IP level are required such that the MAG would see it and need to recreate mobility sessions (see, e.g., the HA switch approach defined in IETF specification RFC 5142) .

Further, when implementing the present invention no separation of control plane and user plane traffic is required mandatory.

Furthermore, the LMA and the GRE load balancer can use their internal prioritization of flows and change them without needing to inform any external entity about it. Here, a re- prioritization may need signalling back a new uplink GRE key to the MAG during the next PBU/PBA message exchange.

While embodiments and applications of this invention have been shown and described above, it should be apparent to those skilled in the art, that many more modifications (than mentioned above) are possible without departing from the inventive concept described herein. The invention, therefore, is not restricted except in the spirit of the appending claims. Therefore, it is intended that the foregoing detailed description should be regarded as illustrative rather than limiting .

LIST OF REFERENCES:

I domain of a communications network, in which mobility management of mobile nodes is per- formed

10 MAG

II uplink traffic or mobility session respectively in a domain of a communications network

12 uplink traffic or mobility session respectively in a domain of a communications network

13 uplink traffic or mobility session respectively in a domain of a communications network

14 a tunnel in a domain of a communications network 15 LMA

16 GRE load balancer

161 selecting module of a GRE load balancer

162 key assigning module of a GRE load balancer

163 data managing module of a GRE load balancer 164 receiver of a GRE load balancer

165 transmitter of a GRE load balancer

166 key determining module of a GRE load balancer

17 a set of service blades or sub LMAs respectively provided in a LMA 171 a service blade or sub LMA respectively provided in a LMA

1711 receiver of a service blade or sub LMA respectively

1712 transmitter of a service blade or sub LMA re- spectively

1713 key determining module of a service blade or sub LMA respectively

172 a service blade or sub LMA respectively provided in a LMA 173 a service blade or sub LMA respectively provided in a LMA

21 transmission of a PUB message from a MAG to a

LMA 22 transmission of a PUB message from a LMA to a GRE load balancer

23 dynamic determining of an uplink key

24 selecting of a service blade or sub LMA respec- tively

25 assigning of a determined uplink key to a selected service blade or sub LMA respectively

26 transmission of a PBA message from a GRE load balancer to a MAG 31 transmission of a PUB message from a MAG to a

LMA

32 transmission of a PUB message from a LMA to a GRE load balancer

33 selecting of a service blade or sub LMA respec- tively

34 providing of a PUB message a GRE load balancer to a selected service blade or sub LMA respectively

35 dynamic determining of an uplink key 36 transmission of a determined uplink key from a selected service blade or sub LMA respectively to a GRE load balancer

37 assigning of a determined uplink key to a selected service blade or sub LMA respectively 38 transmission of a PBA message from a GRE load balancer to a MAG

41 transmitting of data from MAG to LMA

42 transmitting of data from LMA to GRE load balancer 43 detecting of a service blade or sub LMA respectively associated to an uplink key

44 providing of data from a GRE load balancer to a service blade or sub LMA respectively

45 routing of data in the communications network by a service blade or sub LMA respectively

Claims

1. A network component, said component being configured to perform load balancing in a domain of a communications net- work, in which mobility management of mobile nodes is performed, and comprising:

- a selecting module configured to select a routing component from a set of routing components of a home agent entity in said domain, said routing components being configured to man- age binding states of mobile nodes in said communications network; and

- a key assigning module configured to assign an uplink key to said routing component, said uplink key being configured to mark an uplink traffic in said domain belonging to a mo- bility session in said communications network.

2. The network component according to claim 1, said network component comprising a receiver configured to receive a proxy update binding message, wherein said selecting module is con- figured to select said routing component after receiving of said proxy update binding message by said receiver.

3. The network component according to claim 1 or 2, said network component comprising a transmitter configured to trans- mit a proxy binding acknowledgement comprising said uplink key.

4. The network component according to at least one of the preceding claims 1 to 3, said network component comprising a key determining module configured to determine said uplink key to mark said uplink traffic.

5. The network component according to at least one of the preceding claims 1 to 4, said network component comprising a data managing module configured to:

- receive data with said uplink key; and - provide said data to said routing component, assigned to said uplink key, for routing said data in said communications network.

6. The network component according to at least one of the preceding claims, wherein said network component is comprised in said home agent entity.

7. The network component according to at least one of the preceding claims, wherein said home agent entity is a local mobility anchor.

8. A method, said method comprising balancing of loads in a domain of a communications network, in which mobility manage- ment of mobile nodes is performed, by a network component, wherein said balancing of loads comprises:

- selecting of a routing component from a set of routing components of a home agent entity in said domain, said routing components being configured for managing of binding states of mobile nodes in said communications network; and

- assigning of an uplink key to said routing component, said uplink key being configured to mark an uplink traffic in said domain belonging to a mobility session in said communications network .

9. A computer program product comprising a code, the code being configured to implement a method according to claim 8.

10. A data carrier comprising a computer program product ac- cording to claim 9.

11. A routing component, said routing component being configured to be selected from a set of routing components by a network component when performing load balancing in a domain of a communications network, in which mobility management of mobile nodes is performed, wherein:

- said set of routing components is comprised in a home agent entity in said domain; - said routing components are configured for managing of binding states of mobile nodes in said communications network; and

- said network component is configured to perform said load balancing; said routing component comprising:

- a receiver configured to receive data from said network component; and

- a transmitter configured to route said data in said commu- nications network.

12. The routing component according to claim 11, said routing component comprising a key determining module configured to determine an uplink key, said uplink key being configured to mark an uplink traffic in said domain belonging to a mobility session in said communications network.

13. The routing component according to claim 12, wherein said key determining module is configured to determine said uplink key if said data received by said receiver is a proxy update binding message.

14. The routing component according to claim 12 or 13, wherein said routing component comprises a transmitter con- figured to transmit a proxy binding acknowledgement, comprising said uplink key, to said network component.

15. The routing component according to at least one of the preceding claims 11 to 14, wherein said home agent entity is a local mobility anchor.

16. A method, said method being implemented by a routing component, wherein said routing component is configured to be selected from a set of routing components by a network compo- nent when performing load balancing in a domain of a communications network, in which mobility management of mobile nodes is performed, wherein: - said set of routing components is comprised in a home agent entity in said domain;

- said routing components are configured for managing of binding states of mobile nodes in said communications net- work; and

- receiving of data from said network component by said rout- ing component, selected from said set of routing components; and

- routing said data in said communications network.

17. A computer program product comprising a code, the code being configured to implement a method according to claim 16.

18. A data carrier comprising a computer program product according to claim 17.

19. A network entity, wherein:

- said network entity is configured as a home agent in a domain of a communications network, in which mobility management of mobile nodes is performed; and

- said network entity comprises a set of routing components, wherein at least one of said routing components is a routing component according to claim 11.

20. The network entity according to claim 19, wherein said network entity comprises a network component according to claim 1.

21. The network entity according to claim 19 or 20, wherein said network entity is a local mobility anchor.