Abstract:
A system and method for achieving load balancing in a communication network. Each User Equipment (UE) configured to a Femto Access Point (FAP) is grouped under a particular access class based on the quality of service being subscribed to, by the UE. At the time of overloading, each access class is barred access for a particular percent of duty cycle. When an authorized UE requests connection to the FAP, the system checks for an overloading situation. If overloading is detected in the network, the system identifies the access class of that particular UE and checks if that particular access class is authorized to access the FAP at that particular instant of time. If the UE&#39;s access class is authorized to access the FAP at that instant of time, the system allow UE to establish connection.

Description:
TECHNICAL FIELD 
       [0001]    The embodiments herein relate to wireless communication networks and, more particularly, to load balancing in Femto cell based wireless communication networks. 
       BACKGROUND 
       [0002]    Load balancing is the process by virtue of which load in a network is divided among various network components performing same function. Load balancing helps to reduce overloading in a network. Major advantages of Load balancing comprise improved response time and redundancy. By means of load balancing, the load on each network components can be reduced which in turn help improve efficiency of the devices. Further, even if a network component fails to function, the other components take up the work of failed component and the system can be still kept functional. 
         [0003]    Load balancing can be done using software or hardware or both. In an existing method for load balancing, a Femto Access Point (FAP) checks if overloading situation exists in the network. If overloading is detected in the network, the FAP rejects the connection request from the UE. Disadvantage of this method is that the UE will not be permitted to connect to the network till the overloading condition is eliminated. 
         [0004]    In another existing method for load balancing, upon reception of connection request from a UE, the FAP checks if overloading situation exists in the network. If overloading is detected, the FAP redirects the request to a macro cell. A problem existing with this method is that a macro cell might not be able to provide as much signal strength as provided by a Femto cell. 
       SUMMARY 
       [0005]    In view of the foregoing, an embodiment herein provides a method for user equipment (UE) to connect to a Femto access point (FAP) in a Femto network. Upon reception of a connection request from the UE, the method checks if an overloading situation exists in the network. If an overloading situation is detected in the network, the method checks if the UE belongs to an authorized class. If the UE belongs to an authorized class, the method permits access for that particular UE. If the UE does not belong to an authorized class, the method denies connection for that particular UE. 
         [0006]    Further, the Femto access network comprises a Femto access point (FAP). The FAP checks if an overloading situation exists in the network when the UE requests a connection. If an overloading situation is detected in the network, the FAP checks if the UE belongs to an authorized class. If the UE belongs to an authorized class, the FAP permits access for that particular UE. If the UE does not belong to an authorized class, the FAP denies connection for that particular UE. 
         [0007]    These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0008]    The embodiments herein will be better understood from the following detailed description with reference to the drawings, in which: 
           [0009]      FIG. 1  illustrates a general block diagram of a Femto cell network as disclosed in the embodiments herein; 
           [0010]      FIG. 2  is a block diagram which shows the components of a Femto Access Point (FAP) as disclosed in the embodiments herein; 
           [0011]      FIG. 3  is a flow diagram which describes various steps involved in the process of allocation of access classes as disclosed in the embodiments herein; and 
           [0012]      FIGS. 4A-4B  are flow diagrams which describe various steps involved in the process of load balancing as disclosed in the embodiments herein. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0013]    The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein. 
         [0014]    The embodiments herein disclose a method for load balancing in a Femto network by barring connection of each access class in corresponding periods of duty cycle. Referring now to the drawings, and more particularly to  FIGS. 1 through 4B , where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments. 
         [0015]      FIG. 1  illustrates a general block diagram of a Femto cell network as disclosed in the embodiments herein. The system comprises User Equipments  101 , Femto Access Point (FAP)  102 , Internet  103  and Femto Gateway  104 . The UEs  101  access the cellular network through FAP  102  and Femto gateway  104  over internet network  103 . In an embodiment, UE  101  may be any mobile communication device such as mobile phone, laptops, PDAs and so on. Further, the FAP  102  accepts and processes connection requests from UE  101 . In an embodiment, the FAP  102  checks if the UE  101  is permitted to access the FAP  102  upon reception of connection request from the UE  101 . In another embodiment, the FAP  102  identifies a UE  101  using UE specific parameters. In another embodiment, the UE specific parameters may be any or all of International Mobile Subscriber Identity (IMSI)/Electronic Serial Number (ESN)/International Mobile Equipment Identity (IMEI) or any such user equipment specific parameter. In another embodiment, the FAP  102  categorizes UEs  101  into certain sets called access classes. In certain situations, the network may get overloaded, affecting the system performance adversely. In an embodiment, the network may get overloaded when multiple UEs  101  access the network and perform data transfer simultaneously. In another embodiment, the FAP  102  compensates for the overloading situation by selectively dropping services to UEs  101  in certain access classes. Further, FAP connects to the cellular network using an internet connection  103 . The Femto gateway  104  manages traffic between FAPs  102  and the cellular network. In an embodiment, the Femto gateway  104  also perform authentication of each FAP and interfaces the FAP with mobile network core switches using standard protocols. 
         [0016]      FIG. 2  is a block diagram which shows the components of a Femto Access Point (FAP) as disclosed in the embodiments herein. The FAP  102  comprises Femto Management Module (FMM)  201 , memory unit  202 , Access class Management Module (AMM)  203  and a Duty cycle Calculator (DC)  204 . The Femto management module  201  is responsible for effective deployment of Femto cells in a communication network. Further, the Femto management module  201  processes the connection request from the UE  101 . The memory unit  202  comprises a UE ID list which gives information about the UEs  101  which are permitted to access that particular FAP  102 . The Access Class Management Module (AMM)  203  is responsible for allocation of access classes for UEs  101 . In an embodiment, the AMM  203  allocates access classes for UE based on certain parameters. In another embodiment, the parameters considered while allocating access classes for UE may comprise Quality of Service (QOS) subscribed to by that UE  101 , the nature of traffic (VoIP traffic may receive a higher priority than normal traffic and so on) and so on. The Duty cycle Calculator (DC)  204  present in the FAP  102  calculates duty cycle of that particular Femto network. In an embodiment, duty cycle implies the ratio of the time for which the network is active to the total time for which the machine is ON. In another embodiment, the calculation of duty cycle is needed for the purpose of load balancing. 
         [0017]      FIG. 3  is a flow diagram which describes various steps involved in the process of allocation of access classes as disclosed in the embodiments herein. A UE  101  can only access FAP/FAPs  102  which that particular UE is configured to. In an embodiment, the FAP  102  maintains a list of UEs which are permitted to access that particular FAP  102 . In another embodiment, the list may comprise UE specific parameters for identification of UEs  101 . In an embodiment, the UE specific parameters present in the list may be any or all of International Mobile Subscriber Identity (IMSI)/Electronic Serial Number (ESN)/International Mobile Equipment Identity (IMEI) or any such user equipment specific parameter. Once the UE  101  is configured to a FAP  102 , the AMM  203  present in the FAP checks ( 302 ) Quality of Service subscribed by that UE. Based on the QOS, the AMM  203  assigns ( 303 ) access class for that particular UE. In an embodiment, UE  101  with high QOS is assigned to higher access classes. In another embodiment, UE  101  in higher access class has more chance of getting access to the access channels. The various actions in method  300  may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in  FIG. 3  may be omitted. 
         [0018]      FIGS. 4A-4B  are flow diagrams which describe various steps involved in the process of load balancing as disclosed in the embodiments herein. UE  101  initially makes a connection request to an FAP  102 . The FAP receives ( 401 ) the connection request from UE  101  and checks ( 402 ) if the UE  101  is authorized to access the FAP  102 . In an embodiment, the FAP  102  maintains a list of permitted users. In another embodiment, the FAP  102  verifies if the UE  101  is authorized or not by checking if that particular UE  101  is present list. If the UE  101  is authorized to access the FAP  102 , the FAP analyzes ( 403 ) network traffic. In an embodiment, the FAP  102  analyzes network traffic so as to identify if an overloading condition exists in the network. The FAP then checks ( 404 ) if an overloading situation is detected in the network. If overloading is not detected, the UE  101  is allowed ( 405 ) to establish a connection to the FAP  102 . If an overloading situation is detected, the Access class Management Module  203  identifies ( 406 ) the access class to which that particular UE  101  belongs to. Then the FAP checks ( 407 ) if the UE  101  belongs to a permitted access class or not. In an embodiment, at the time of overloading, the FAP  101  bars access for selected access classes. In another embodiment, the FAP  102  may use any one of a round robin method, fair queuing method, proportionally fair scheduling, maximum throughput algorithm to select the access class to be terminated at a particular period of duty cycle. The FAP  102  may also use any other suitable scheduling method to cycle through the classes. If the UE  101  is found to be a member of a permitted access class, that particular UE  101  is allowed to connect to the FAP  102 . If the UE  101  is found to belong to an unauthorized service class, the FAP  102  fails ( 408 ) authentication of that particular UE  101 . Upon authentication failure, the FAP  102  activates ( 409 ) a timer. In an embodiment, the timer may be a T3216 timer or any such suitable timer. In another embodiment, the timer value is preset by the system. The UE  101  waits till expiry of the timer. Once timer got expired, the UE  101  scans for a suitable FAP  102  and requests for connection. The various actions in method  400  may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in  FIGS. 4A-4B  may be omitted. 
         [0019]    The embodiments disclosed herein can be implemented through at least one software program running on at least one hardware device and performing network management functions to control the network elements. The network elements shown in  FIG. 2  include blocks which can be at least one of a hardware device, or a combination of hardware device and software module. 
         [0020]    The embodiment disclosed herein specifies a system for load balancing in a communication network. The mechanism allows load balancing by selectively dropping a group of User Equipments (UE) providing a system thereof. Therefore, it is understood that the scope of the protection is extended to such a program and in addition to a computer readable means having a message therein, such computer readable storage means contain program code means for implementation of one or more steps of the method, when the program runs on a server or mobile device or any suitable programmable device. The method is implemented in a preferred embodiment through or together with a software program written in e.g. Very high speed integrated circuit Hardware Description Language (VHDL) another programming language, or implemented by one or more VHDL or several software modules being executed on at least one hardware device. The hardware device can be any kind of device which can be programmed including e.g. any kind of computer like a server or a personal computer, or the like, or any combination thereof, e.g. one processor and two FPGAs. The device may also include means which could be e.g. hardware means like e.g. an ASIC, or a combination of hardware and software means, e.g. an ASIC and an FPGA, or at least one microprocessor and at least one memory with software modules located therein. Thus, the means are at least one hardware means and/or at least one software means. The method embodiments described herein could be implemented in pure hardware or partly in hardware and partly in software. The device may also include only software means. Alternatively, the invention may be implemented on different hardware devices, e.g. using a plurality of CPUs. 
         [0021]    The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the claims as described herein.