WO2006093350A1

WO2006093350A1 - Resource control system and method in a communication network

Info

Publication number: WO2006093350A1
Application number: PCT/JP2006/304669
Authority: WO
Inventors: Saravanan Govindan; Hong Cheng; Pek Yew Tan
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2005-03-04
Filing date: 2006-03-03
Publication date: 2006-09-08

Abstract

A resource control system and method for reorganizing resource allocation and adaptively controlling the resources in the communication network are disclosed. In the system or method proposed by the present invention, a resource processor (CN-RP) in the communication network, upon receiving a resource request message (ResReq) from a resource processor (CS-RP) such as a mobile terminal in step (205), determines the feasibility of the resource allocation in step (210). In case that the resource allocation is feasible, CN-RP reorganizes resources in consideration of resource allocation about other communication sessions in step (215), and offers the resource calculated by reorganization to CS-RP in step (220). CS-RP determines the acceptability of this offered resource allocation in step (225). If this offered resource allocation is acceptable, CS-RP sends a resource acceptance message (Res Acc) in step (230), and accommodates the resources.

Description

DESCRIPTION

RESOURCE CONTROL SYSTEM AND METHOD IN A COMMUNICATION NETWORK

TECHNICAL FIELD

The present invention pertains to resource control in a communication network, and more particularly, it relates to the resource management technology for QoS (Quality of Service) support in a mobile environment.

BACKGROUND ART

Communication networks comprise limited resources such as bandwidth, buffer space, processing cycles, etc. For the purpose of Quality of Service, current resource control schemes statically allocate these limited resources to communication sessions. Specifically, communication traffic is provisioned with resources at a given instance and the provisions remain unchanged for relatively extended time periods.

Such resource controls are therefore one-time provisions. They are made irrespective of the dynamics of the networks. For example, QoS resources at an access point are provisioned at the beginning of a streaming video session and remain valid for the lifetime of the session at the access point. Similarly, when a communication session moves from the first access point to the second access point, the initial resource allocations at the former are invalidated while new provisions are made at the second access point for the duration of the session there.

Since such static one-time resource allocation methods do not account for the dynamics in traffic characteristics, they are increasingly inadequate for modern networks. This is because there are substantial fluctuations in traffic characteristics with the current rapid growth in network usage. Furthermore, as communication networks are deployed in locations featuring transient patterns - such as railway stations and airports - communication traffic is being characterized by sudden and brief bursts of activity followed by lulls. Resource allocation and admission control procedures in these networks must be expedited due to the short duration in which the sessions will be active.

The following non-patent document 1 illustrates the increasing dynamism of communication network traffic. On this basis, it is evident that there is a profound mismatch between the dynamic traffic characteristics and the static methods of provisioning resources to such traffic. Such a mismatch adversely affects network performance. In particular, it hampers admission control and mobility support. Due to the overheads of static and one-time provisioning, resource control cannot be carried out promptly to enable mobility and other time critical features. As a result, new communication sessions with high resource requirements may be denied admission or existing sessions with lower resource requirements may be preempted and disrupted in order to admit the new session. In both cases, resource control fails to optimize network utilization and consequently denies revenue to the network service provider.

The following patent document 1 illustrates a method for adjusting priority resources in individual communication packets. The method introduces some dynamism to resource allocation.

The following patent document 2 describes a resource allocation method in which a mobile terminal explicitly adjusts QoS settings. This method offers advantages over traditional network-centric QoS allocation mechanisms .

The following patent document 3 discloses a mechanism for maintaining resource allocations in wireless communication networks by means of restricting admission to new sessions. This is achieved by adapting the received power threshold at the network.

The following non-patent document 2 describes a means for adapting the strength of a beacon signal of a base station so as to adjust admission to network services.

Patent document 1: US 6,760,309 Bl, "Method of Dynamic Prioritization of Time Sensitive Packets over a Packet Based Network," March 2000.

Patent document 2: GB 2,380,900 A, "Altering Quality of Service for a Mobile," October 2001.

Patent document 3: US 2004/0152422 Al, "Method and Device for Controlling Admission of Users to a Cellular Radio Network," October 2003.

Non-patent document 1: "Internet Traffic Report," <URL:http : //www. internettrafficreport . com>

Non-patent document 2: "Traffic Sharing Scheme for Distributed Dynamic Channel Allocation, " IEEE Mobile & Personal Communications, December 1993.

The prior arts discussed above illustrate the problems with static one-time resource allocation mechanisms. In particular, they indicate how unreliable admission control based on these mechanisms can be. It is evident that with existing methods, the cost of inefficient admission control is great for both the performance of a communication network and for the service providers of the network. Furthermore, the prior arts lack accuracy in providing fine-grained resource allocation and consequently fine-grained admission control.

With respect to the patent document 1, while the method disclosed therein introduces some dynamism to resource allocation, it only does so after a communication session has been admitted to the network. The method does not overcome the stated problem of repeating initial allocation procedures for each newly arriving communication session.

With respect to the patent document 2, due to the distributed nature of its operation among a plurality of mobile terminals, the method introduced by the patent document 2 prolongs the process of resource allocations during admission control thereby negating its efficacy in dynamic traffic environments.

With respect to the patent document 3, while the mechanism disclosed therein is a marked improvement over existing static methods, this mechanism does not address how the allocations may be made in the first place.

With respect to the non-patent document 2, despite its intuitive appeal, the means disclosed therein does not allow for selective admission control and subsequent resource allocation. This is because beacon signal adaptation affects all mobile terminals in the vicinity of the base station and not particular mobile terminals.

DISCLOSURE OF THE INVENTION

To solve the above problems, it is the first object of the present invention to provide systems and methods for reorganizing resource allocations and adaptively controlling resources in a communication network.

Furthermore, it is the second object of the present invention to provide systems and methods for adapting resource allocation parameters and reorganizing resource allocations .

Furthermore, it is the third object of the present invention to provide systems and methods for adapting resource limiter parameters and reorganizing preexisting resource allocations.

The present invention addresses the above- mentioned problems relating to static provisioning of network resources. In particular, the present invention addresses the dynamic characteristics of modern communication traffic. Static and one-time resource allocations adversely affect the performance of communication traffic whose resource requirements vary over time and magnitude. Specifically, static allocations prevent timely admission control, reduce QoS performance, deny user experience and reduce revenue for communication network service providers.

The present invention addresses the above- mentioned problem by adapting resource allocations to accurately suit the needs of communication traffic of differing characteristics. As a result, the present invention ensures that dynamic traffic conditions are met with corresponding dynamic resource provisioning.

The present invention provides a resource control system in a communication network for controlling resource allocation for each of a plurality of communication sessions, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource with respect to each of the plurality of communication network resources; means for determining resources necessary to be reorganized among one or more resources of the plurality of communication network resources in consideration of allocation states where the resources are allocated to each of the plurality of communication sessions, in case of allocating resources to a new communication session; and means for dynamically reorganizing the resources by adapting the resource allocation parameters of the resources necessary to be reorganized and reorganizing portions of allocated resources; whereby, the resources are allocated to the plurality of communication sessions and the new communication session in consideration of a balance of all communication sessions including the plurality of communication sessions and the new communication session,

The present invention provides a resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource; and means for managing resources to be allocated to the communication session by associating the resource allocation parameters to time components.

The present invention provides a resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource; means for binding validity of resources allocated to the communication session, to a single or plurality of resource limiter parameters; and means for managing the validity of resources by using the resource limiter parameters.

The present invention provides a resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource; means for calculating feasibility of the resource allocation for the communication session, and determining whether or not the resource allocation can be performed, by comparing the calculated feasibility to a predetermined standard value.

The present invention provides a resource control system in a communication network for controlling resource allocation for a communication session, wherein a communication device which requests resource allocation to the communication network, upon receiving a resource allocation offer from the communication network, evaluates whether or not the offered resource allocation is acceptable based on any one or a combination of deviation between the requested and offered resource allocation, deviation tolerance, cost of offered resource allocation, and user preference of the communication device.

The present invention provides a resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for polling resource information to a single or plurality of resource state managing devices which manage resource state in the communication network; means for indicating change of allocated resource to the resource state managing device. The present invention provides a resource control method performed by a resource control system in a communication network for controlling resource allocation for each of a plurality of communication sessions, comprising the steps of: associating a single or plurality of resource allocation parameters to a corresponding network resource with respect to each of the plurality of communication network resources; determining resources necessary to be reorganized among one or more resources of the plurality of communication network resources in consideration of allocation states where the resources are allocated to each of the plurality of communication sessions, in case of allocating resources to a new communication session; and dynamically reorganizing the resources by adapting the resource allocation parameters of the resources necessary to be reorganized and reorganizing portions of allocated resources; whereby, the resources are allocated to the plurality of communication sessions and the new communication session in consideration of a balance of all communication sessions including the plurality of communication sessions and the new communication session.

The present invention provides a resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session, comprising: a step where a first communication device relative to the network session requests the resource allocation to a second communication device which manages resources in the communication network; and a step where the second communication device determines whether or not the resource allocation can be performed for the first communication device; a step where, in case that the resource allocation can be performed, the second communication device offers resource allocation to the first communication device; a step where the second communication device reorganizes the resources according to the offered resource allocation to the first communication device; a step where the first communication device determines whether or not the offered resource allocation is acceptable from the second communication device; a step where the first communication device sends information that the offered resource allocation is acceptable to the second communication device in case that the first communication device accepts the offered resource allocation; and a step where the second communication device allocates resources defined by the offered resource allocation to the first communication device when the second communication device receives the information that the offered resource allocation is acceptable from the first communication device.

The present invention provides a resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session wherein the resource allocation is performed for the communication session in collaboration with another communication network.

The present invention provides a resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session, comprising the steps of : polling resource information to a single or plurality of resource state managing devices which manage resource state in the communication network; indicating change of allocated resource to the resource state managing device.

The present invention provides a resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session wherein the communication network changes resource allocation parameters associated to resources in collaboration with another communication network so as to change the communication session from the communication network to another communication network, or from another communication network to the communication network, and whereby failover about the communication session is supported.

The present invention comprising the foregoing construction have the advantages of reorganizing resource allocations and adaptively controlling resources in a communication network, adapting resource allocation parameters and reorganizing resource allocations, and adapting resource limiter parameters and reorganizing preexisting resource allocations. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing an example of a communication system in the embodiment of the present invention; FIG. 2 is a diagram showing an operational sequence in the embodiment of the present invention;

FIG. 3 is a diagram showing another example of a communication system in the embodiment of the present invention; FIG. 4 is a diagram showing another operational sequence in the embodiment of the present invention;

FIG. 5 is a block diagram showing a system level representation of WAP based on the IEEE 802.11 specifications in the embodiment of the present invention;

FIG. 6 is a diagram showing an operational flow of a plurality of resource limiters in the embodiment of the present invention;

FIG. 7 is a diagram showing an operational sequence to describe collaboration among two communication .network;

FIG. 8 is a diagram showing a sequence of message exchange in the embodiment of the present invention; FIG. 9 is a diagram showing examples of MAC frame format and frame control field format in the embodiment of the present invention; and

FIG. 10 is a diagram showing an example of resource allocation for communication sessions, adaptive with respect to a time component in the embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Descriptions will be hereinafter given of embodiments of the present invention. In the following descriptions, for the purpose of explanation, specific numbers, times, structures and other parameters are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

With reference to FIG. 1, a communication network (CN) (100) provides services to a single or plurality of communication stations (CS) , such as CS (115). CN (100) comprises an admissions controller (AC) (105) and a resource processor (RP) (110) . AC (105) and RP (110) may collocate with other network elements. For instance, the combined network element may additionally comprise authentication functionalities and authorization capabilities. The combined network element may also be part of a larger network entity such as a radio (wireless) access point, a cellular base station or other network processing entity. In Fig. 1, a communication network (CN) (125) with an admission controller (AC) (130) and a resource processor (RP) (135) is also illustrated in addition to CN (100) . CN (100) comprises a plurality of resources that are provisioned to a single or plurality of communication sessions. Such resources may be limited and comprise, for example, priority resources, buffer space, processing cycles and Quality of Service (QoS) resources. There may also be any number of additional or replacement resources. The validity of each resource allocation (may be simply recited as allocation in this specification) is governed by a resource limiter, which is related to each of the resource allocations. Resource limiters may be individually associated to or aggregated for a plurality of resource allocations. Upon expiry of the resource limiter, the resource is free to be alternatively allocated. One example of a resource limiter is a time component wherein each resource allocation is limited by time duration.

AC (105) performs admission of new communication sessions and reorganizes admission of existing communication sessions. Admission control by AC (105) comprises authentication and authorization of communication sessions and the corresponding communication stations. Additionally, AC (105) uses resource allocation inputted from RP (110) for the purpose of its operations.

RP (110) is responsible for the monitoring, allocation and reorganization of resources of CN (100). These operations are performed with an aim of achieving desired performance criteria. Performance criteria may comprise QoS elements such as bound latency and jitter, response time and priority. AC (105) and RP (110) collaboratively operate to admit communication sessions and provision network resources. The ultimate decision of admission control, however, rests with AC (105) .

CS (115) is an end-point of network traffic and may be source or destination of communication sessions. As a physical entity, it may be mobile or fixed. CS (115) comprises a resource processor (RP) (120) which is tasked with requesting appropriate resources, evaluating and adapting to resource availability. RP (120) of CS (115) differs from RP (110) of CN (100) in that the latter primarily operates as provider of resource allocations to the former. As such, RP (120) of CS (115) primarily operates as requester of resource allocations. Requests may be made for specific or range of resources. For example, a request may be made for a particular priority level '6' for duration of 10 to 30 milliseconds. Requests for resource allocations are generated by RP (120) on the basis of a single or plurality of inputs. These inputs comprise predetermined triggers, historic and current statistics, state of active communication applications and human or machine interface prompts. CS (115) and CN (100) are communicably coupled by means of a single or plurality of communication protocols. Such protocols may comprise IP (Internet Protocol), IEEE 802.11, IEEE 802.16, IEEE 802.15, CAPWAP (Control and Provisioning of Wireless Access Points) , GSM (Global System for Mobile Communication) , CDMA (Code Division Multiple Access), WCDMA (Wideband Code Division Multiple Access) and CDMA2000. AC (105) and RP (110) of CN (100) operate within the scope of such communication protocols. Communication coupling (113) indicates a radio (wireless) connection between CS (115) and CN

(100) . However communication coupling (113) may also be a cable (wireline) connection. As a result, the coupling may be wireless over radio frequencies or wireline over copper or fiber based connections. The sequence of operations between resource processors RP (110) and RP (120) of CN (100) and CS (115), respectively, is described hereinafter with reference of FIG. 2. In FIG. 2, "CN-AC" and "CN-RP" represent AC (105) and RP (110), respectively, of CN (100) while "CS-RP" represents RP (120) of CS (115) .

In the operational sequence (200), RP (120) of CS (115) sends a resource request message (ResReq) (205) to the RP (110) of CN (100) with which it seeks resource allocations and consequently network service. This message specifies the desired allocation parameters for a single or plurality of communication sessions of CS (115). Allocation parameters comprise the type and level of requested resource allocation in addition to a resource limiter. The resource limiter determines the validity of an allocation based on a single or plurality of criteria. Such criteria for a resource limiter may comprise a time component, latency threshold, jitter threshold, traffic volume threshold, transmission characteristics or any combinations of such. An additional criterion for a resource limiter is the size of input, output, or other intermediate buffers, for example the size of receive and transmit buffers. Buffers represent memory locations. The buffer size criteria can also be combined with time duration. For instance, one criterion for a resource limiter is the usage duration for a given amount of buffer space.

Another criterion related to those discussed insofar is the rate of buffer usage. This specifies the change in buffer usage over time. By associating a resource limiter with each allocation, the present invention enables resources to be systematically and dynamically reorganized so as to achieve desired network performance. A ResReq (205) from RP (120) of CS (115) may be exemplified by 'Latency Threshold', '10ms', ' lhr ' and '10Mb' for resource type, resource level, time component, and traffic volume threshold, respectively. The time component and traffic volume threshold constitute the resource limiter parameters. The request in this example is made for a suitable resource allocation in which communication sessions from CS (115) will encounter network latency below '10ms'. The allocation is to remain valid for a period of 'lhr' or for the duration of transmission of '10Mb' of traffic volume.

In a further example, resource limiter parameters may specify boundary limits such that a resource allocation is valid within a range of values. The resource limiter parameters may also be weighted so as to assign relative degrees of significance for an allocation. From the above example, the time component parameter may have a weight of 80% while the traffic volume threshold may have a weight of 20%. As a result, the resource allocation may tolerate traffic volume exceeding the corresponding threshold more than the session duration exceeding the time component. The following Equation 1 exemplifies the weight for resource limiter parameters in which 'RL', 'Total', 'P' and ¹W denote the resource limit, number of resource limiter parameters in ResReq (205), resource limiter parameter and its weight, respectively.

Equation 1:

RL = ∑_n=i ^n=τotal (Wn x Pn)

RP (110) of CN (100) communicates the result of a computation such as Equation 1 to RP (120) of CS (115) Furthermore, RP (110) also applies a computation such as Equation 1 for communication sessions to determine their respective resource usage levels. The resource limiter may also be computed using functions alternative to Equation 1.

Upon receiving ResReq (205), RP (110) of CN (100) determines the feasibility of the requested resource allocation in a step (210) . Feasibility is computed as a function of available free resources, volume of existing allocations, expectation of future resource requests, cost of resource allocations and opportunity costs of denying requests. Feasibility correlates positively with greater availability of free resources and higher opportunity costs of denying resource requests. On the other hand, feasibility correlates negatively with increase in volume of existing allocations, higher expectations of future resource requests and greater costs of resource allocations. Feasibility is also a function of the resource limit, which may be computer as in Equation 1. The result of the above computation is then compared to an allocation margin, which ultimately determines the feasibility of the requested resource allocation. Therefore, the feasibility is determined as a comparative function with respect to an allocation margin.

Equation 2 presents an example of a general structure for computing feasibility.

Equation 2:

[R_A - (C x {f (RL + R_R) } x R_EF) + C₀] ≥ FM

wherein 'R_A' refers to available resources, 'C is the cost of requested resource, 'R_R' and ¹RL¹ are the requested resource allocation and its resource limit, ' f ( ) ' is an aggregation function of 'R_R' and 'RL¹, 'R_EF' is the expected future resource requests, 'C₀' is the opportunity cost of denying the request or alternatively the beneficial cost of provisioning the request and 'FM' is the feasibility margin. So using the example Equation 2, if the outcome is true for the given parametric values, then ResReq (205) is determined to be feasible whereas if false, ResReq (205) is determined to be unfeasible.

Costs may be a measure of finance, computation capability, management effort and overhead. Feasibility margin may be statically predetermined or dynamically varied according to changes in network conditions .

It will be clear to those skilled in the art that the feasibility determination may also comprise any number of functions and factors either as additions or replacements to those listed above while remaining within the scope of the present invention.

Once the feasibility of ResReq (205) or portions thereof is determined, RP (110) of CN (100) communicates the results of the feasibility determination to AC (105) Admissions control operations are executed with this additional information. Specifically, AC (105) conducts authentication and authorization of the communication session for which ResReq (205) is made. Admissions control operations utilize the results of the feasibility determination from RP (110) to determine the admission of and subsequent resource allocation for a communication session. In one embodiment based on the IEEE 802.11 specifications, AC (105) of CN (100) processes the MAC management frames corresponding to 'Authentication' and 'Association' . AC (105) also executes various authentication operations such as the 4-way handshake and security key exchanges.

Once AC (105) has determined the admission of the communication sessions, RP (110) prepares for the corresponding allocation in step (215) . In this step (215), extant resource allocations for admitted communication sessions are appropriately reorganized so as to accommodate the new request ResReq (205).

Specifically, the resource reorganization of step (215) comprises adapting the resource limiter parameters of a single or plurality of resource allocation. In one example of adaptive resource limiter parameters, the duration of validity of existing allocations is altered so as to make available resources for the new request ResReq (205). In another example, resource reorganization (215) may be achieved by means of adapting a single or plurality of other fields or parameters of the resource allocation. For instance, the resource level field may be adapted from 'High' to 'Low' .

After completion of the resource reorganization of step (215), RP (110) of CN (100) sends a resource notification message (ResNoc) (220) to RP (120) of CS (115) . ResNoc (220) comprises an offer of resource allocation, which further comprises information regarding resource type, level and resource limiter. The resource limiter field defines the validity of the specified resource allocation offer. ResNoc (220) may comprise a plurality of resource allocation information corresponding to a plurality of resource limiters. The implication is that alternate types and levels of resources may be allocated over different ranges.

Upon receipt of ResNoc (220), RP (120) of CS (115) determines whether or not the resource allocation is acceptable, or the acceptability of the resource allocation in step (225) . A plurality of aspects is required for this step. First, RP (120) of CS (115) evaluates ResNoc (220) based on costs of the offered resource allocation, opportunity costs of rejecting the offered allocation, user preference and comparative allocations from alternative communication networks. Acceptability is also evaluated as a function of the deviation of the resource notification, ResNoc (220), from the resource request, ResReq (205) . The deviation may be mathematically determined as the difference between ResNoc (220) and ResReq (205) . Acceptability correlates negatively with high costs of offered allocations, high opportunity costs of rejecting offered allocations and better comparative allocations.

Acceptability correlates positively with favorable user preferences and smaller deviations of ResNoc (220) from ResReq (205) .

Equation 3 illustrates an example of a function for evaluating acceptability. Equation 3 :

[R_Ni x (C-C₀)] x g_±-i {RN±} X d{R_R-R_Ni} x UI] ≥ AM

where ' R_Ni ' is the resource notification from the first communication network "i", ¹C and 'C₀' are the cost and opportunity cost of the offered resource allocation, respectively, gi-i{ } is a comparative function that analyses resource offers relative to an alternative communication network "i-1", d{ } is a deviation function between the requested resource allocation ¹RR' and resource notification from the first communication network, 'UI' is the input from the user in terms of preference, policy etc. and 'AM' is the acceptability margin. 'AM' may be predetermined statically or dynamically. In other embodiments of the present invention, acceptability may be computed as a function of communication session requirements, costs and deviation tolerance. Acceptability can also be determined by alternative computations. In one example, acceptability determination

(225) is based on the relative change in cost of allocation. For instance, if a subscriber is offered ResNoc (220) with lower levels of resource allocation at significantly reduced costs, the new allocation is evaluated to be acceptable. Further, user preference for a ResNoc (220) or portions thereof, may relate to user level aspects such as loyalty programs or other rewards schemes.

Next, RP (120) of CS (115) sends a resource acceptance message (ResAcc) (230) indicating acceptance of the allocations of ResNoc (220) or portions thereof. Then in step (235), RP (110) of CN (100) prepares to reorganize extant allocations and prepares to provision resources to new communication sessions of CS (115) according to ResAcc (230). The preparation of resource provisioning is confirmed upon AC (105) confirming admission of new communication sessions. After the preparations for reorganization and allocation of resources, RP (110) then sends a resources ready message (ResRed) (240) to admission controller (AC (105)). Upon receiving ResRed (240), AC (105) finalizes admissions of the communication session and sends an admission grant message (GRT) (245) to both RP (110) of CN (100) and CS (115). Upon receipt of GRT (245), RP (110) finalizes and confirms the resource provisioning such that the appropriate resources are ready for communication sessions of CS (115) . GRT (245) may also be sent to other communication network entities as an indicator of the new admission. EMBODIMENT SPECIFIC TO TIME COMPONENT> In one embodiment, resource allocations are specifically adapted with respect to time components associated with the allocations. Here, each resource allocation made by CN (100) to a communication session from CS (115) is associated with a single or plurality of time components. The validity of each resource allocation is therefore limited by the duration specified by the corresponding time component. CN (100) then provisions resources efficiently by varying the time component for portions or levels of resources.

FIG. 10 illustrates resource allocation (1000) for communication sessions from CS (115). Allocation

(1000) is adaptive with respect to time components. In FIG. 10, it shows the time component on the x-axis (1005) and resource allocation level on the y-axis (1010) . According to the present invention, each level of resource allocation is valid for a specified duration according to its time component. So in the allocation (1000), a resource level (1015) is allocated to communication sessions of CS (115) for a time component (1013). In the allocation, time components are varied for different resource levels thereby allowing for more effective provisioning of resources within the overall CN (100) .

Allocation (1000) is equally applicable to both CS and CN. For the former CS, the allocation represents the request for resources over period of time and for the latter communication network, the allocation represents the provisioning of resources over a period of time. The advantage with such a method of resource allocations is that it allows for efficient use of resources for dynamic time-varying communication traffic. EMBODIMENT FOR OPERATIONS IN 802.11 SPECIFICATIONS AND CAPWAP>

In one embodiment, operative steps of the present invention are described in relation to a wireless access point (WAP) functioning according to the IEEE 802.11 specifications. FIG. 5 shows a system level representation of such a WAP (500) in a communication network. WAP (500) comprises a number of system blocks each with a plurality of function modules. The Reception system block (REC) (505) receives communication frames from the physical layer (510) and appropriately forwards them to other system blocks (OthBlk) (525), which comprise 'MLME_AP', 'MPDU_Generation' , ' Protocol_Control ' and ' Distribution_Service ' . The functioning of the entirety of the system blocks constitutes the operations of the IEEE 802.11 specifications.

Each of the system blocks comprises a plurality of function modules. According to the IEEE 802.11 specifications, REC (505) comprises a ' Filter_MPDϋ' function module (FILT) (515) together with other function modules (OthMod) (520). Upon receipt of communication frames from the link of the physical layer (PHY) (510), FILT (515) is responsible for validation, decryption and filtering of said communication frames. Filtering is based on information comprising frame header fields such as type, subtype, source address, destination address, previous-hop address, next-hop address and checksum. Such analysis of communication frames may also be accomplished by means of other information such as arrival time, rate and frame size. Upon filtering, the communication frames are forwarded to appropriate function modules (520) and system blocks (525) .

The present invention involves system blocks of Resource Processor (RP) (110) and Admissions Controller (AC) (105) operating together with the system blocks

(505) and (525) of the IEEE 802.11 specifications. RP (110) and AC (105) perform the steps of the invention based on the operational sequence (200) by means of interaction with REC (505) and OthBlk (525) . This interaction may also be accomplished with function modules (520) and system blocks (525) of other standards specifications such as CDMA, 3GPP (3rd Generation Partnership Project) and GSM.

The operational sequence (200) interrelates with those of the IEEE 802.11 specifications. In this embodiment, the operational messages of the invention are exchanged among system blocks RP (110), AC (105), REC (505) and OthBlk (525) by means of management and control frames of the IEEE 802.11 specifications. Specific 'type' and 'subtype' codes are used to distinguish frames for resource allocation from other frames. For example, based on the IEEE 802.11 specifications, unused reserved 'subtype' codes between '0000' to '1001' for control frames and 'subtype' codes between '0110' to '0111' for management frames may be used for distinction. Alternative mechanisms for distinguishing frames carrying resource allocation information may also be used.

In this embodiment, when function module FILT (515) of system block REC (505), receives communication frames related to resource allocation, it forwards them to system block RP (110) for further handling. In the present invention, the filtering logic of FILT (515) comprises features additional to that of the IEEE 802.11 specifications. These additional features comprise recognition of resource allocation messages and system blocks, reinforcement of admission control and other such related functionalities.

Next, system blocks RP (110) and AC (105) exchange resource allocation messages based on the operational sequence (200). Within the sequence (200), each of RP (110) and AC (105) may correspond with REC (505) or OthBlk (525) for means of obtaining information or affecting resource allocations.

In particular, upon receiving ResReq (205) or in a predetermined regular manner, system block RP (110) determines feasibility of resource allocation in a step (210) by evaluating resources available in the communication network. This is achieved by RP (110) communicating with various system blocks to determine their individual levels of resources. For instance, RP (110) communicates with the scheduler of a

'Transmission' system block within OthBlk (525) to determine available scheduling and timing resources. Similarly, RP (110) communicates with memory and processor managers to evaluate corresponding resource availability. As a result, the present invention introduces communication links between RP (110), AC (105) and other function modules (520) and system blocks (525) of a WAP (500) operating on the basis of the IEEE 802.11 specifications. Such links may be exemplified by means of application program interfaces between RP (110), AC (105) and the other function modules (520) and system blocks (525) .

System blocks RP (110) and AC (105) are also enabled with means of effecting change in the function modules and system modules they are in communication with. Such means enables the resource reorganization step (215) . Particularly, the means for effecting change involves adjusting parameters for resource allocations. For example, scheduling resources are affected by means of priority parameters and memory resources are affected by utilization parameters.

Finally, upon completion of resource allocation operations, the communication session for which resources have been allocated is granted admissions by means of the Grant (GRT) message (245) . This message is directed from AC (105) to RP (110), the communication station for which the resource allocation was made and to appropriate system blocks (505) and (525) . This message (GRT (245) ) completes one operational cycle of the present invention. This embodiment illustrates how the disclosed invention operates within the scope of the IEEE 802.11 specifications. Based on this embodiment of WAP (500), the invention thereby also applies to the Internet Engineering Task Force (IETF) Control and Provisioning of Wireless Access Points (CAPWAP) working group (WG) in which mechanisms for QoS control for large scale wireless local area networks are standardized. Various operative steps of the invention may also function across CAPWAP split architectures. EMBODIMENT FOR INVENTION WORKING IN 802.11 WLAN STATIONS> In one embodiment of the invention that extends the previous, the invention operates within the scope of communication stations, such as CS (115), operating according to the IEEE 802.11 specifications. EMBODIMENT ON DIFFERENT WAYS OF MANAGING QOS>

The resource allocation operations of the present invention may be based on a plurality of resource limiters. FIG. 6 illustrates the operational sequences of the invention in various contexts (600) of resource limiters . It shows the sequential flow of operations from an initial resource trigger (ResTrg) (605) step. ResTrg (605) may comprise a plurality of triggers such as impending handovers, changes in resources allocations, receipt of ResReq (205) from a communication station and predetermined schedules.

Once a trigger is received, the remainder of the operations commences. Because the current invention applies to the allocation of a plurality of resources, it is necessary to determine appropriate resource limiters for each type of resource trigger (605) . This is determined in step (610) in which resource triggers (605) are mapped to a single or plurality of resource limiters time component (615), scheduling priority (620), buffer space (625) and processor time (630) . For example, if ResTrg (605) is determined to be that of impending handover, appropriate resource limiters would comprise scheduling priority (620), buffer space (625) and processor time (630) . In another example a trigger due to receipt of ResReq (205) may comprise the resource limiter of time component (615). Next, based on the appropriate resource limiters for a ResTrg (605), resource allocations are reorganized to accommodate the cause of ResTrg (605) . This is achieved by means of adapting the validity of a single or plurality of appropriate resource limiters in steps (635), (640), (645) and (650) for time component, scheduling priority, buffer space and processor time resource limiters, respectively. Each of said steps further comprises alterations to relevant resource limiter parameters. In step (635), parameters resource type (636), resource level (637) and duration of validity (638) are altered for the time component resource limiter. In step (640), parameters resource type (641) and priority level (642) are altered for the scheduling priority resource limiter. In step (645), parameters buffer type (646) and buffer occupancy levels (647) are altered for the buffer space resource limiter. In step (650), parameters processor type (651) and processing duration (652) are altered for the processor time resource limiter. Other resource limiters and corresponding parameters may also be used in the present invention of resource allocation.

Once resource allocations for a ResTrg (605) have been reorganized, a resource allocation is offered to accommodate the trigger in step (655). The offer in then confirmed in step (660) or alternatively the reorganization steps are repeated. Once the offer is confirmed, ResTrg (605) is accommodated (665).

This embodiment describes the operational sequence of the present invention. It illustrates how a plurality of resource limiters may be adapted to accommodate resource triggers. EMBODIMENT ON HANDOVERS>

An embodiment of the present invention relating to handover of communication sessions from one communication network to another is described. There are two aspects to this embodiment. The first aspect deals with the reorganization of resource allocations effected by handovers. The second aspect deals with handovers affected by reorganization of resource allocations. Both of these aspects may be considered as resource triggers (605).

In the first aspect, a handover of a communication session of communication station (115) from the first communication network (100) to the second communication network (125) introduces changes at both of said networks in FIG. 1. Particularly, in CN (100), portions of network resources previously allocated to CS (115) become available whereas in CN (125), portions of resources are requested. The present invention addresses these changes by means of adapting resource allocations across CN (100) and CN (125) in coordination.

Typically, handovers are accommodated by means of exchanging contextual information between CN (100) and CN (125) regarding the communication session of CS (115) . This is to ensure consistency in network performance for CS (115) . In the present invention, this contextual information comprises resource requirements, ResReq (205), for the communication session of CS (115). This acts as trigger, ResTrg (605), for CN (125) . CN (100) also receives ResTrg (605) due to the resources that have been divested by CS (115) at CN (100) . As a result of the handover, additional resources are made available to CN (100) for alternative allocations. Resource triggers (605) for CN (100) and CN (125) may be concurrent or displaced in time.

Next, upon receiving the trigger, both CN (100) and CN (125) proceed with the operation sequence (200) in conjunction with the operational flow (600). Additionally, the two communication networks (100) and (125) coordinate their respective operational steps.

FIG. 7 shows the collaborative sequence of steps for CN (100) and CN (125) . It illustrates the relative timing of the operative steps for the two communication networks (100) and (125) .

Particularly, CN (125) begins the feasibility determination step (210) before CN (100) commences the resource reorganization step (215) . This is to ensure that CS (115) is consistently allocated with appropriate resources at both communication networks as the handover process occurs. Furthermore, CN (100) may bypass its own feasibility determination step (210).

After CN (125) determines feasibility of allocating resources to the communication session of CS (115), both CN (100) and CN (125) pursue the resource reorganization step (215) based on a single or plurality of resource limiters (615), (620), (625) and (630). While the reorganization steps are identical, their respective goals for the two communication networks may differ. Specifically, CN (125) reorganizes resource allocations for the purpose of accommodating a new communication session of CS (115) . CN (100) reorganizes resource allocations for the purpose of delivering enhanced performance to existing communication sessions.

Upon completion of the resource organization step (215), CN (100) and CN (125) provision appropriate resources in step (235) . Again, provisioning at CN (125) precedes that of CN (100) because CN (100) addresses a handover communication session while CN (125) addresses relatively static preexisting communication sessions. Then upon provisioning resources, CN (125) completes the handover process by granting admission (GRT (245)), to the communication session of CS (115) .

In the second aspect of the embodiment for handovers based on the present invention, resource reorganizations effect handovers of existing communication sessions. This situation of resource reorganizations effecting handovers arises when the reorganizations are adverse to existing communication sessions. For example, consider a communication session with low priority requirements and capable of preemption by a communication session with high priority. So when such a high priority communication session is admitted, the resulting resource reorganizations may not appropriately suit the low priority communication session. As a result, the low priority session is preempted and performs a handover to an alternative communication network where allocated resources are more appropriate.

In such cases, the present invention operates on the basis of resource reorganizations themselves being triggers (605) for subsequent resource reorganizations. This feature of the invention enables comprehensive resource allocation capabilities.

The operations of this aspect of the embodiment follow those of the operational sequence (200) and operational flow (600). Particularly, the operative steps are staggered relative to each other to follow the respective stages of operation. So once the trigger (605) is determined to be that of resource reorganization, subsequent steps are executed as per the first aspect of this embodiment. So coordination among communication networks is also enabled in this aspect.

The two aspects of this embodiment for handovers based on the present invention illustrate how communication sessions of communication stations may be steered from the first communication network to the second so as to maintain individual and overall network performance levels. So resource allocations are adapted to steer communication sessions to communication networks that are most adequate for allocating resources and consequently, providing services.

<MESSAGE SEQUENCE EMBODIMENT

FIG. 8 illustrates the exchange sequence of messages (800) for the present invention of resource allocation. In addition to those of operational sequence (200) and operational flow (600), the invention comprises a 'Poll¹ message (PLL) (805) and an 'Effect' message (EFF) (810) . These two messages work with various communication network entities by means of polling for information or effecting changes on the status quo of resources. These two messages ensure that operations are based on reduced set of messages.

PLL (805) is used to determine existing status quo of resource allocations. It is employed to determine the level of available resources, status of existing resource allocations and other such information gathering operations. PLL messages (805) are sent by resource processors (RP) or access controllers (AC) to resource managing entities (RME) . Resource processors (RP) differ from resource managing entities (RME) in that the former oversees overall resources in a communication network whereas the latter control specific resources. Typically, each network resource is controlled by a single or plurality of RMEs. PLL messages (805) are also used by RMEs to respond with appropriate information. EFF (810) is used to prepare and effect change in resource allocations. EFF messages (810) are sent by RPs and ACs to RMEs of appropriate resources. EFF messages (810) include additional parameters that are specific to resources. For example, EFF messages (810) sent to a network buffer will include a set of parameters comprising buffer occupancy level and occupancy duration. Further parameters may be those from the operational flow (600). EFF messages (810) are also used by RPs to confirm changes in resource allocations once admissions have been confirmed. Exchange sequence (800) illustrated in FIG. 8 shows four entities, access controller (AC) , resource managing entity (RME) , resource processor (RP) and communication station (CS) . AC, RME and RP are those of a communication network (CN) at which resources are to be allocated for CS. These are identical to those entities described in earlier embodiments of the present invention for resource allocation.

In the first step, a resource request, ResReq (205) , is issued from CS to RP of a communication network. In general, the commencement of operations of the disclosed invention is by means of a resource trigger, ResTrg (605), which may comprise a number of events such as impending handovers, changes in resources allocations, receipt of ResReq (205) from a CS and predetermined schedules.

Next, upon receiving a ResTrg (605) or ResReq (205), RP proceeds to determine the feasibility of allocating resources to accommodate ResTrg (605) or ResReq (205) . So, appropriate resources are polled for relevant information by means of sending a single or plurality of PLL messages (805) to corresponding RMEs. While PLL (805) may be standard across all RMEs, variations are also enabled so as to selectively retrieve (or to selectively transmit) information regarding network resources. In FIG. 8, PLL (805) for different resources are distinguished by subscripts, (1), (2) and (x) .

The RMEs for the resources respond to PLL (805) with information regarding the status of resources. This information comprises the availability of resources, level and validity of resource allocations. RMEs also use PLL (805) for responses. In FIG. 8, responses are distinguished by the subscript (R) .

Then once RP obtains the necessary information on resources, it determines an offer for resource allocation to accommodate ResTrg (605) or ResReq (205) . This offer is then notified to CS by means of the resource notification message, ResNoc (220). CS then determines the acceptability of the offered resource allocation and responds with a resource acceptance message ResAcc (230) for portions or the entirety offer. Upon receiving ResAcc (230) , RP then proceeds to correspondingly prepare the allocation of resources. So changes are effected in various resources by means of sending appropriate RMEs with EFF (810) messages. EFF (810) messages comprise parametric values for the various resources. Upon receiving EFF (810), RMEs correspondingly prepare and update resource allocations. After preparations for resource allocations have been made, RP notifies AC of the allocations by sending a resources ready message, ResRed (240) . AC then performs additional aspects of admissions control comprising authentication and authorization. After admissions related aspects are complete, AC sends a grant message, GRT (245), to RP and CS indicating granting of admission. GRT (245) may also be sent to RMEs of various resources as an indication of admissions. Upon receiving GRT (245) , RP confirms resource allocations by sending another EFF message. In FIG. 8, confirmation EFF (810) messages are distinguished by the subscript (C) . This embodiment describes the sequence of messages of the present invention for resource allocation. It illustrates the advantageous use of a reduced set of messages so as to simplify large scale deployment and management of the invention.

In another embodiment of the present invention, a communication station CS (115) proactively determines which of a plurality of communication networks to seek admission with. CS (115) determines its choice of communication network by means of determining acceptability of a plurality of resource notifications ResNoc (220) received from each of resource processors RP (110) and RP (135) from each of available communication networks CN (100) and CN (125) , respectively.

In this embodiment, RP (120) of CS (115) sends a resource request message ResReq (205) to a plurality of available communication networks CN (100) and CN (125). Upon receipt of ResReq (205) , subsequent operations of sequence (200) are performed.

<AUTOMATIC VERSION OF PREVIOUS EMBODIMENTS

In an alternative embodiment, the resource request message ResReq (205) and feasibility- determination (step (210)) are forgone. Consequently each of resource processors (RP (110) and RP (135) ) of CN (100) and CN (125), respectively, regularly perform step (215) of optimally reorganizing extant allocations and determining available resources. The communication networks CN (100) and CN (125) then broadcast their respective resource notification messages ResNoc (220) .

Upon receiving a plurality of ResNoc (220), RP (120) of CS (115) then determines the acceptability of the allocations in step (225) . Additionally, RP (120) evaluates the relative acceptability of the plurality of ResNoc (220) and advantageously determines the communication network from which ResNoc (220) delivers higher benefits.

Next having determined the communication network with higher benefits, RP (120) of CS (115) sends a resource acceptance message ResAcc (230) to the corresponding resource processor RP. Upon receiving ResAcc (230) from CS (115), RP of said determined communication network performs appropriate resource provisioning according to step (235) and sends a resources ready message (ResRed) (240) to the admissions controller (AC) . The admissions controller (AC) then sends an admissions grant message (GRT) (245) to both the RP of the determined communication network and CS (115). Upon receipt of GRT (245), CS (115) is admitted for service at the said determined communication network.

This embodiment illustrates the advantages of the present invention in enabling choice within a communication station so as to advantageously determine a communication network with which to gain admission.

The operative procedures indicate the simplicity of the method for gaining admission and allocating resources for a communication station.

EMBODIMENT OF APS (Advanced Planning and Scheduling) COORDINATING RESOURCE ALLOCATIONS> In another related embodiment, a resource request message ResReq (205) is accommodated by a plurality of communication networks in a time shared manner. For example, RP (110) of CN (100) allocates resources for the first duration of 100ms and then RP

(135) of CN (125) allocates corresponding resources for the second duration of 200ms. As a result, the resources of independent communication networks CN (100) and (125) are collaboratively deployed to accommodate ResReq (205) of CS (115) .

In this embodiment, the resources of a plurality of communication networks are collaboratively deployed in meeting the requirements for communication sessions. The benefits from such collaboration enhance reliability for the sessions and optimize network performance.

EMBODIMENT FOR FAILOVER SUPPORT OF FAILING AP>

In one embodiment of the present invention, a means for adapting resource allocations so as to accommodate a failing WAP or communication network is presented. Prevailing market trends indicate that wireless services will be provided by a plurality of small service providers, each covering relatively small geographies. The small service providers will share broader network infrastructure so as to benefit from cost efficiencies. In such scenarios, due to the inconsistencies among the plurality of small service providers, consistent network service is at risk. For example, one such small service provider may be a small coffee shop where owners provide network service as a value-added feature. Due to the profile of such an establishment, network service may be disrupted due to problems in power supply to WAPs and other network equipment. Disruptions may also be regularly scheduled due to business strategies or other competitive reasons.

The present invention for resource allocations is applied in such scenarios to provide consistent network service by means of steering communication sessions from WAPs or communication networks with impending disruptions to alternative WAPs or communication networks. In essence, the steps for resource allocations enable failover support for WAPs and communication networks.

In relation to FIG. 1, CN (100) is assumed to be that of a small service provider at which disruption will occur. The methods for determining impending disruption comprise predetermined notification and continuous sensing. Alternative mechanisms may also be employed. The capability for determining network service disruption is available with WAPs and communication networks. When impending disruption at CN (100) is determined, neighboring WAPs or communication networks such as CN (125) commence the process of assisting communication sessions of CS (115) . In the first step, RP (135) of CN (125) requests RP (110) of CN (100) for resource and context information regarding the communication sessions of CS (115) . This is achieved by means of sending PLL (805) messages from CN (125) to CN (100) . CN (100) then responds with appropriate resource and context information using PLL (805).

The PLL (805) response acts as resource trigger, ResTrg (605), for CN (125) after which RP (135) commences the operations of the present invention according to the operational steps (200) and operational flow (600). In coordination with CN (125), CN (100) also commences the operational steps (200) and operational flow (600) in a manner as to reduce resource allocations to CS (115). Such coordination presents CS (115) with an incentive to steer its resource requirements away from CN (100) towards CN (125) . This is achieved by means of the resource notification message, ResNoc (220), sent by both CN (100) and CN (125) during the operation of the steps.

As a result, CN (125) assists CS (115) in the light of disruptions at CN (100) . This embodiment of the invention illustrates the beneficial application of coordination of resource allocation procedures across a plurality of communication networks. The result is that failovers of WAPs or communication networks are supported by the present invention. FIG. 3 illustrates another embodiment of the present invention in which a plurality of communication networks (300) collaboratively determines the feasibility of maintaining an admitted communication session. Operational sequence (400) of FIG. 4 is used to do describe this embodiment.

In FIG. 3, the admissions control and resource processor operations of communication networks CN (305), (310) and (315) are represented by access points (AP) (320), (325) and (330), respectively. CS (335) comprises a resource processor (not illustrated) for evaluating resource notification messages ResNoc (220). CS (335) is initially admitted to CN (305) and maintains a corresponding ResNoc (220) previously received from AP (320). Communication coupling between CS (335) and its communication network is by means of a single or plurality of communication protocols such as IEEE 802.11, IEEE 802.16 and CAPWAP.

During the course of operation, communication networks are subject to congestion and disruptions in communication media. Consequently, admissions of communication sessions and respective allocations of resources require reorganization so as to accommodate changes in the communication network.

Having determined the need to reorganize, AP (320) of CN (305) coordinates with AP (325) and AP (330) of CN (310) and (315) , respectively, so as to effect change in admission of CS (335) from AP (320) to an alternative access point. In this embodiment, resource notification messages ResNoc (220) from each of the access points are collaboratively adapted and sent to CS (335). The plurality of communication networks are communicably coupled by means of a single or plurality of communication protocols such as IP, IEEE 802.11, IEEE 802.16, GSM, CDMA, WCDMA and CDMA2000.

Specifically, upon congestion or any disruption, AP (320) sends a reorganization request message (OrgReq) (405) to alternative access points (325) and (330). OrgReq (405) comprises information on the allocation made by AP (320) to CS (335) such as resource type, level and time component. Additional information may be included such as historic and current statistics of CS (335) .

Upon receipt of OrgReq (405), AP (325) and AP (330) perform steps (210) and (215) of determining the feasibility and of allocating resources for CS (335) respectively, and reorganizing extant allocations correspondingly. AP (325) and (330) also determine a suitable increment in allocation which may be offered to CS (335). For example, given an initial allocation with time component of 10ms made by AP (320) to CS (335), AP (325) determines a suitable allocation increment with time component of 20ms. As a result of such higher benefits, AP (325) provides incentive and thereby prompts CS (335) to alter its existing admission with AP (320) by seeking new admission with AP (325) .

Having determined allocation increments, AP (325) and (330) send corresponding resource notification messages ResNoc (220) to CS (335) . Upon receipt, CS (335) determines the acceptability of the new ResNoc (220) in step (225) . Additionally, CS (335) evaluates the relative acceptability of the new ResNoc (220) on the basis of its existing allocation with AP (320) . Due to the allocation increments of the new ResNoc (220) from AP (325) and (330), CS (335) advantageously determines an alternative communication network with which to seek new admission and receive higher benefits. Next having determined the communication network with higher benefits, CS (335) sends a resource acceptance message ResAcc (230) to the corresponding access point. In FIG. 4, the determined communication network is exemplified to be CN (315) represented by AP (325). Upon receipt of ResAcc (230), AP (325) confirms the new admission and responds with an admissions grant message ( GRT ( 245 ) ) .

Once CS (335) receives GRT (245), it sends an admission cease message (AdmCea) (410) to AP (330) of its previous CN (305). Consequently, CS (335) ceases its admission with AP (320) and chooses to gain admission with an alternate access point of an alternate communication network. As a result, congestion or other disruptions at CN (305) are accommodated to by means of effecting change of extant admissions and allocations to alternative new admissions and allocations. The present invention thereby ensures reliable network performance without the complexity of disrupting existing communication sessions.

EMBODIMENT RELATING TO IEEE 802.11 FRAME TYPES>

In one embodiment based on the IEEE 802.11 specifications, messages of the sequence of operations (200) and (400) are transported using IEEE 802.11 frames. Specifically, a predetermined 'Frame Type' code is for transporting messages of operation sequences (200) and (400). Alternatively, extant management frames with predetermined 'Subtype' or 'Duration/ID' codes are used to transport the messages. Both communication station and communication network are preconfigured to recognize frames with said predetermined codes and process such frames correspondingly. In extensions to the embodiment, IEEE 802.11 data or control frames may be used to transport messages of operation sequences (200) and (400) .

FIG. 9 illustrates the use of IEEE 802.11 frames for the purpose of transporting messages of operation sequences (200) and (400) . FIG. 9 shows a representation of the MAC frame format (905) in accordance to the IEEE 802.11 specifications. MAC frame format (905) comprises a number of fields for identification, direction and error control. In particular, this includes a frame control field (910) and a Duration/ID field (915) .

The frame control field (910) is further defined by a format (920). The frame control field format (920) comprises a type field (925), subtype field (930) and other indicative fields. The IEEE 802.11 specifications define a set of two-bit codes for the type field (925) and a set of four-bit codes for the subtype field (930) . For instance, type codes '00', ¹Ol' and '10' denote management, control and data frames, respectively. Subtype codes define frames of greater specificity.

In one embodiment of the invention, IEEE 802.11 MAC frames transporting messages of operation sequences (200) and (400) are distinguished from other IEEE 802.11 MAC frames such as management, control and data frames. Frame control field format (935) illustrates the difference. The type field (925) of frame control field format (935) contains a reserved type code '11'. This type code indicates that the corresponding MAC frame transports messages pertaining to operation sequences (200) and (400) . Further, the subtype field (930) of frame control field format (935) contains reserved subtype codes in the range of '0000' - '1111'. These codes define specific messages of the operation sequences (200) and (400) such as Resource Request, Resource Notification and Resource Acceptance.

In an alternative embodiment of the present invention, a combination of codes for type field (925), subtype field (930) and Duration/ID field (915) can further distinguish IEEE 802.11 MAC frames transporting messages of operation sequences (200) and (400) .

EMBODIMENT FOR OPERATIONS IN MOBILE IP>

Similar to the embodiment relating to IEEE specifications, the present invention may also be embodied in relation to Mobile IP. The embodiment is detailed with respect to FIG. 1 where CS (115) is first within its home network of CN (100) and later moves to a foreign network CN (125) . Upon mobility, the availability of resources at foreign network CN (125) , in the form of ResNoc (220), is notified to CS (115). In this embodiment of the present invention, ResNoc (220) is included as part of the Mobile IP agent advertisements which CN (125) sends out. As a result, when the mobile CS (115) receives a care-of-address from CN (125), it is also made aware of the available resources and proposed allocations at the foreign network.

Alternatively, in this embodiment, CS (115) includes its request for resource allocations in its Mobile IP agent solicitations. When the foreign agent in CN (125) receives such an agent solicitation, it combines its advertisement together with ResNoc (220) message.

This embodiment illustrates how the present invention advantageously operates with Mobile IP. As such, the invention has applicability for resource adaptations within mobile environments.

The aforementioned embodiments of the present invention illustrate means for transporting messages of the operation sequences (200) and (400) using IEEE

802.11 based MAC frames. Consequently, the embodiments show how the invention may be realized within access points and access point controllers that adhere to IEEE 802.11 specifications. This highlights the ease and cost-effectiveness of the present invention. INDUSTRIAL APPLICABILITY

According to The present invention having the advantages of reorganizing resource allocations and adaptively controlling resources in a communication network, adapting resource allocation parameters and reorganizing resource allocations, and adapting resource limiter parameters and reorganizing preexisting resource allocations, can be applied to the fields of resource control in a communication network, especially of the resource management technology for QoS support in mobile or wireless environments.

Claims

1. A resource control system in a communication network for controlling resource allocation for each of a plurality of communication sessions, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource with respect to each of the plurality of communication network resources; means for determining resources necessary to be reorganized among one or more resources of the plurality of communication network resources in consideration of allocation states where the resources are allocated to each of the plurality of communication sessions, in case of allocating resources to a new communication session; and means for dynamically reorganizing the resources by adapting the resource allocation parameters of the resources necessary to be reorganized and reorganizing portions of allocated resources; whereby, the resources are allocated to the plurality of communication sessions and the new communication session in consideration of a balance of all communication sessions including the plurality of communication sessions and the new communication session.

2. The resource control system according to claim 1 wherein the resource allocation parameters comprise type of the resource allocation, level of the resource allocation and dynamic characteristics of the resource allocation.

3. A resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource; and means for managing resources to be allocated to the communication session by associating the resource allocation parameters to time components.

4. The resource control system according to claim 3 wherein the time components of the resource allocation are set according to characteristics of the communication session for which the resource allocation are made.

5. A resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource; means for binding validity of resources allocated to the communication session, to a single or plurality of resource limiter parameters; and means for managing the validity of resources by using the resource limiter parameters.

6. The resource control system according to claim 5 wherein the resource limiter parameters comprise any one or more of time component, latency threshold, jitter threshold, traffic volume threshold, transmission characteristics of the communication session, state of the communication network, processor time, buffer space, scheduling priority, and utilization rate.

7. A resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for associating a single or plurality of resource allocation parameters to a corresponding network resource; means for calculating feasibility of the resource allocation for the communication session, and determining whether or not the resource allocation can be performed, by comparing the calculated feasibility to a predetermined standard value.

8. The resource control system according to claim 7 wherein it is determined whether or not the resource allocation can be performed, based on any one or a combination of availability of the resources, cost of requested resource allocation, opportunity cost of denying request, expected future resource allocation requests .

9. A resource control system in a communication network for controlling resource allocation for a communication session, wherein a communication device which requests resource allocation to the communication network, upon receiving a resource allocation offer from the communication network, evaluates whether or not the offered resource allocation is acceptable based on any one or a combination of deviation between the requested and offered resource allocation, deviation tolerance, cost of offered resource allocation, and user preference of the communication device.

10. A resource control system in a communication network for controlling resource allocation for a communication session, comprising: means for polling resource information to a single or plurality of resource state managing devices which manage resource state in the communication network; means for indicating change of allocated resource to the resource state managing device.

11. A resource control method performed by a resource control system in a communication network for controlling resource allocation for each of a plurality of communication sessions, comprising the steps of: associating a single or plurality of resource allocation parameters to a corresponding network resource with respect to each of the plurality of communication network resources; determining resources necessary to be reorganized among one or more resources of the plurality of communication network resources in consideration of allocation states where the resources are allocated to each of the plurality of communication sessions, in case of allocating resources to a new communication session; and dynamically reorganizing the resources by adapting the resource allocation parameters of the resources necessary to be reorganized and reorganizing portions of allocated resources; whereby, the resources are allocated to the plurality of communication sessions and the new communication session in consideration of a balance of all communication sessions including the plurality of communication sessions and the new communication session.

12. The resource control method according to claim 11, comprising the steps of: binding validity of resources allocated to the communication session, to a single or plurality of resource limiter parameters; and managing the validity of resources by using the resource limiter parameters .

13. A resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session, comprising: a step where a first communication device relative to the network session requests the resource allocation to a second communication device which manages resources in the communication network; and a step where the second communication device determines whether or not the resource allocation can be performed for the first communication device; a step where, in case that the resource allocation can be performed, the second communication device offers resource allocation to the first communication device; a step where the second communication device reorganizes the resources according to the offered resource allocation to the first communication device; a step where the first communication device determines whether or not the offered resource allocation is acceptable from the second communication device; a step where the first communication device sends information that the offered resource allocation is acceptable to the second communication device in case that the first communication device accepts the offered resource allocation; and a step where the second communication device allocates resources defined by the offered resource allocation to the first communication device when the second communication device receives the information that the offered resource allocation is acceptable from the first communication device.

14. The resource control method according to claim 13, wherein the first information that the offered resource allocation is acceptable to the second communication device requests the resource allocation to a plurality of communication devices in the step of requesting the resource allocation, each of the communication devices being in each of the plurality of communication networks and being the second communication device, and wherein the second communication device chooses the offered resource allocation among a plurality of resource allocation offers received from the second communication devices respectively in the step of determining whether or not the offer is acceptable.

15. A resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session wherein the resource allocation is performed for the communication session in collaboration with another communication network.

16. The resource control method according to claim 15 wherein the resource allocation is performed for the communication session in collaboration with another communication network so as to change the communication session from the communication network to another communication network, or from another communication network to the communication network.

17 . The resource control method according to claim 16 wherein the offered resource allocation comprises information on resource allocation change depending on time .

18. A resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session, comprising the steps of: polling resource information to a single or plurality of resource state managing devices which manage resource state in the communication network; indicating change of allocated resource to the resource state managing device.

19. A resource control method performed by a resource control system in a communication network for controlling resource allocation for a communication session wherein the communication network changes resource allocation parameters associated to resources in collaboration with another communication network so as to change the communication session from the communication network to another communication network, or from another communication network to the communication network, and whereby failover about the communication session is supported.