WO2007082918A1 - Managing service quality in a mobile network - Google Patents

Abstract

Method of managing service quality, management entity, attachment point, mobile terminal and computer programmes corresponding thereto. The invention relates to a method of managing the service quality in a cellular network, between at least one mobile terminal and at least one attachment point. According to the invention said network comprises an entity for managing service quality, said method comprises, when setting up a communication session: - a first step in which said management entity transmits a set of classes of services available for said communication session to said mobile terminal; a second step in which said mobile terminal selects a first service class from among said set of available service classes; - a third step in which said mobile terminal transmits said first selected service class to said management entity; a fourth step of associating a service quality context, comprising information representative of said first service class selected, with said at least one attachment point. Figure 1.

Description

 QUALITY OF SERVICE MANAGEMENT IN A MOBILE NETWORK

FIELD OF THE INVENTION

The field of the invention is that of the management of quality of service in communication networks.

More specifically, the invention relates to a method of managing the quality of service in cellular networks based on attachment points. These networks are, for example, those of the world of mobile radiotelephony.

As mobile network speeds and performances increase, mobile communication terminals are carrying out applications that are increasingly interactive and highly dependent on the network's ability to guarantee a quality of service. This QoS ("Quality of Service") is negotiated between the mobile and the cellular network during the re-establishment of the communication sessions. In the remainder of this document we will use indifferently the terms of

"Quality of Service" or "Qos" which designate the same notion. Reference is also made to the following terms:

PA (point of attachment): it is the entity of the cellular network that ensures the attachment of the mobile node to the micro-mobility domain; They can also be rated "AP".

NM (mobile node): here we refer to the mobile terminal. It can be a mobile phone, a PDA, a laptop, etc; Cellular network: it is a network constituted of points of attachment to which the mobile nodes come to connect; - Mobility domain: it is a set consisting of at least one cellular network.

2 Solutions of the Prior Art 2.1 Prior Art

Quality of Service (QoS) support in a mobile network is strongly related to handover and traffic control mechanisms. We call mechanisms for "handover" procedures related to the establishment and maintenance of communication sessions, especially when the mobile terminal changes cells within the network. The ability for a mobility protocol to interact effectively with existing QoS management mechanisms is also very important for QoS support in the case of cellular networks. In this perspective, some research work is trying to find a solution that offers quality of service in mobile networks.

There are currently two broad classes of solutions: those based on the RSVP protocol ("resource reSerVation Protocol" for "resource reservation protocol");

Those stemming from "The differentiated architecture of services".

2.1.1 RSVP fResource Reservation Setup Protocol)

The RSVP signaling protocol, which has been defined by the RSVP Working Group (specification documents available from the IETF), is a dynamic mechanism designed to make explicit resource reservations in an integrated service architecture ("IntServ "). RSVP is only used for communication of "QoS" parameters. RSVP is initiated by an application at the beginning of a communication session. A session is identified by the destination IP address, the transport layer protocol type, and the destination port number. Each RSVP packet contains details about the session to which it belongs. The allocation of resources requested through RSVP for a given stream is independent of

RSVP, which only carries the parameters describing the flows and resources requested. The way in which these are actually reserved on the nodes crossed depends on the "IntServ" architecture. Once the resources requested by RSVP are reserved, they are used for this flow of data.

RSVP establishes and maintains a software state between the nodes constituting the reserved path. The software state is maintained by refresh messages sent periodically along the path to maintain the state. 2.1.1.1 RSVP messages The RSVP protocol defines seven types of messages, the main ones being the "PATH" and "RESV" messages. These two messages ensure the basic operation of RSVP. Other RSVP messages are used either to provide information on the status of reservations or to explicitly cancel reservations along a path of a communication session. All RSVP messages are sent over the network as IP datagrams (packets) with protocol number 46; PATH, PATH Tear, and RESV Conf must be sent with the router alert option enabled.

The "PATH" message is sent by a source (the mobile terminal, for example) that initiates the communication session and sends its requirements to the recipient. The "PATH" message contains the "SenderJTspec" (Transmitter Traffic Specification) field used by the source to specify the traffic characteristics of its data streams. All network elements ^• • •• which passes the message "PATH" and the recipient himself, set up a state session information described in PATH. ADSPEC is another field of the "PATH"message; this optional field provides a status indication on the network.

After receiving the message "PATH", the recipient RSVP sends a request "RESV" which specifies the desired QoS and which travels the opposite way. Apart from the information concerning the reservation style desired by the receiver ("Filter" field), the "RESV" message contains two fields, "FlowSpec" and "FilterSpec", which constitute the flow description. "FlowSpec" defines the requirements for the data flow, ie the type of service requested (guaranteed or load control), - the service parameters to invoke the QoS ("RSpec"), the parameters of the service. stream requesting this service ("TSpec"). The "FilterSpec" field, on the other hand, sets the appropriate parameters for the classification of packets.

Each RSVP node, upon receipt of the "RESV" message, performs the admission check, reserves the appropriate resources, and returns the request to upstream node. This process is repeated until the source. The RSVP transmitter can then send the data.

In case of failure of the reservation, an error message is sent. Note that, unlike the "PATH" messages that are sent to the session address (unicast or multicast), the "RESV" messages are sent to the unicast address of the sender.

2.1.1.2 Booking Process with RSVP

An RSVP session is defined as follows:

<session> = <DstAddr, PID, DstPort> Where "DstAddr" is the destination IP address of the data, "PID" is the protocol identifier, and "DstPort" is the UDP destination port ("User Datagram Protocol" "For" User Packet Protocol ") or TCP (" Transmission Control Protocol "for" Transmission Control Protocol "). The RSVP signaling messages are sent jump-jump between RSVP routers as raw IP packets with the protocol identifier 46, reserved for RSVP signaling. An RSVP message consists of a common header followed by a variable number of objects.

A typical RSVP message is defined as:

<RSVPMessage> = <header> <objectl> <object2> ... Suppose a source wants to reserve resources to the receiver, it sends a "PATH" message:

<PATH> = <header> <DestAddr, PID, DstPort> <SourceAddr> ... where "SourceAddr" and "DestAddr" are respectively the IP address of the source and the destination. When the first RSVP router "Rl" receives this message, it hides the routing information contained in this message and sends another "PATH" message to the following router:

<PATH> = <header><DestAddr, PID, DstPort><RlAddr> ... and so on step by step to the receiver of the message. The effective reservation only takes place when sending the "RESV" messages, which follow the inverse path of the "PATH" messages and whose content depends on the information hidden in the routers.

2.1.2 The service-differentiated architecture The second class of solutions is represented by those based on the "DiffServ" architecture or service-differentiated architecture.

The Differentiation of Services architecture ("DiffServ" whose specification documents are available from the IETF) is a result of efforts to resolve the complexity and scalability issues (such as the Internet) posed by "IntServ". Scaling up becomes possible by providing services to aggregates rather than by each flow and pushing flow processing to the ends of the network. The goal is to leave the heart of the network as simple as possible.

The application flows called "micro-flows" are aggregated according to their QoS constraints. In contrast to "micro-flows", the aggregation is called "macro-flow" and represents all flows of the same class of service (QoS). The routers perform the treatments no longer on micro-streams (too many in the Internet) but on macro-streams whose number is limited. Macroflots are then managed in domains. A domain represents a contiguous portion of the Internet controlled by the same administrative authority.

2.1.2.1 Principle of the Differentiation of Services Architecture

The differentiation of services is mainly carried out:

Through the "DS" field ("Differentiated Service" for "Service"

Differentiated ") or" DSCP "(" Differentiated Services Code Point "for" Differentiated Services Code Point ") in the IP header of packets;

Associated behavior ("Per-Hop Behavior" or "PHB").

"DiffServ" divides the network into domains; a domain is a group of nodes that work with a common set of service allocation policies and PHB definitions. A "DiffServ" domain consists of two types of functional elements: border elements and core elements of the network.

Border elements are responsible for packet classification and traffic conditioning based on Service Level Agreements (SLAs) between neighboring domains. An "SLA" is a bilateral agreement between domains, statically or dynamically negotiated. According to the SLAs, appropriate Service Level Specification (SLS) are assigned to the border nodes. The SLS contains parameters such as transmission capacity, burst size, and peak rate.

2.1.2.2 Classification of traffic

The classifier selects packages based on the combination of a single or a set of stub fields. The correspondence of the traffic with the ι specific behaviors of different classes of service is indicated by the field "DS". Each value in the "DS" field uniquely identifies a "PHB". "DiffSev" supports up to 64 classes of service. Each router sorts packets in files following the "DS" field. The queues will receive different processing based on priority, bandwidth sharing, and packet rejection policies. 2.1.3 The NC-HMIPv6 protocol

NC-HMIPv6 is a micro mobility management protocol developed within France Telecom (Société Anonyme). In a domain supporting NC-HMIPvβ, a mobile node (for example a mobile terminal, a telephone) continuously monitors the quality of its radio link with its current access point. If it degrades below a threshold Sl, the mobile node collects the measurements of its quality with the neighboring access points. Measurements of known access points are sent to its mobility server in a "handover" request. This makes it possible to reduce the size of the handover request thanks to a first selection made by the mobility server. The handover request is an IP v6 packet with a new handover request destination option. The mobility server consults these metrics and decides to which neighboring access point the mobile node should move.

The mobility server then returns its handover response to the mobile node specifying the elected target access point. In parallel, it creates a new association (VCOA, nLCOA) with nLCOA the future address of the mobile node in association with the target access point.

The mobile node receives the handover response, moves to the selected network and acquires the prefix. He builds his future nLCOA address (concatenating his physical interface identifier with the network prefix of his future access network). As soon as it attaches to the new access point, the mobile node must send announcements of neighbors in order to make known its new correspondence (IP address, nLCOA, link layer address). The trip ends with a confirmation of its new destination with the - mobility server and an acknowledgment of the latter. In the case where the router already has an entry for the MN or data to be transmitted to it, the new access router receives the announcement of neighbors of the mobile node with the future address nLCOA, it updates its routing table in mapping the nLCOA IP address to the mobile node link layer address advertised in the neighbor announcement. The connection resumes towards the mobile since the packets intended for the mobile node are already redirected at the level of the mobility server. Then, the mobile node starts a timer to deprecate and then invalidate its old prefixes and old routers by default.

If it is a sub-domain movement, the mobile node issues a registration request to its mobility server in order to update its association (VCOA, nLCOA).

Whenever the mobile node moves and changes access point, it must update its neighbor access point list.

If the optimization of IP micro-mobility management is well defined in wireless networks based on WLAN technology by several protocols like NC-HMIPv6, the mechanisms of management of the quality of service in these networks are not taken into account. The so-called micro-mobility protocols offer powerful solutions for supporting localized mobility. They have the advantage of solving the main limitations of Mobile IP without complicating the mobility management mechanism. In these mobility solutions, there is no guarantee in terms of quality of service. The introduction of Quality of Service (QoS) allows these protocols to provide other classes of service than the traditional "best effort" service. This demand for enrichment of the range of services increases as mobile networks enter society. In this context, working groups of ITETF ("Internet Engineering

Task Force "for" Internet Engineering Detachment ") are working to define mechanisms for integrating quality of service management into mobility management tools. Several methods are already published and proposed to the IETF. Proposals such as "CIRP" ("Cellular IP Reservation Protocol" for "Internet Protocol Reservation Protocol in a Cellular Network"), "MRSVP" ("Mobility Resource Reservation Protocol Protocol" for "Resource Reservation Definition Protocol" Mobile ")," Session Initiation Protocol (SIP) ", manage the quality of service in mobile environments, offering new classes of services.

2.2 Disadvantages of the Prior Art

A disadvantage of these techniques of the prior art is notably related to the RSVP protocol, which is not adapted to a mobility context. Solutions based on the RSVP protocol such as the MRSVP protocol which is a modification of RSVP adapted to cellular networks have been proposed. However, MRSVP requires additional classes of service, major changes to RSVP, prior knowledge of mobile moves (through the definition of mobility profiles) and a lot of signaling during data transport, which has the effect of reducing greatly bandwidth. A corollary disadvantage of this technique of the prior art is that MRSVP assumes that the mobility of a user is predictable so that a mobility specification can be defined for its movements. This mobility specification represents the list of geographical locations that the mobile will visit during the lifetime of a stream. However, apart from some very particular cases, the probabilities of obtaining a mobility specification of a terminal are very low, which makes inoperative the resource reservations that have been made. Indeed, as RSVP operates according to the principle of pre-reservation of resources, if the mobility specification defined for a terminal is incorrect, then the pre-reservations have been made in vain, which contributes to wasting resources of the network.

Another disadvantage of this technique of the prior art is related to the lack of consideration of mobility in the Service Differentiation Architectures. Indeed, these architectures, even if they offer optimized QoS management for traditional networks, are not more efficient for resource reservation processes, which leads to a sharp drop in QoS in the case of a network. cellular since by definition the terminal is mobile and it must systematically perform a "handover" request at each change of node. Yet another disadvantage of this technique of the prior art is related to the absence of QoS management mechanism in protocols such as NC-HMIPvό, and more generally in the context of mobility solutions grafted on existing protocols. Indeed, the proposals such as "CIRP", "MRSVP", "SIP" do not include information, for the mobile, as to the state of the access network and its capacity to offer quality of service requested. In this case, there is a high probability that the mobile terminal will exchange several signaling messages before having a session with quality of service. Thus, when the mobile terminal is not satisfied with the quality offered by the access network, it must re-initialized the application after the re-negotiation of a class of service penalizing the applications very real time. Another disadvantage of the techniques of the prior art is the impossibility for the mobile terminal to negotiate the quality of service during the course of a communication session. Indeed, once initialized, the QoS offered to the mobile node is defined for the entire communication session. Thus, if a mobile node negotiates a degraded service class, it is not possible for it to change during the communication session. This aspect of the current mechanisms is penalizing, especially for real-time applications.

Yet another disadvantage of these prior art techniques is the lack of continuity of service during transfers from one attachment point to another during mobile node moves. Indeed, the current techniques do not guarantee the possibility of maintaining a class of service during a change of point of attachment. For example, in the case of MRSVP the reservation is made end-to-end following a supposed displacement of the mobile. As a result, if the terminal deviates from the predicted path, it loses the assigned QoS and a new handover procedure and resource reservation must be completed before the resource can continue to operate. application running.

3 Objectives of the invention

The invention particularly aims to overcome these disadvantages of the prior art.

More precisely, an objective of the invention is to provide a mechanism that makes it possible to effectively manage the quality of service in a cellular network.

Another objective of the invention is to implement such a mechanism both in the field of micro-mobility and in that of macro mobility. The invention also aims to reduce the necessary exchanges between the mobile terminals and the cellular network during a cell change (handover time).

More specifically, an object of the invention is to provide a technique for maximizing the quality of service provided to mobile applications and avoiding the disadvantages of conventional systems implementing the protocol. RSVP and its derivatives, such as the reservation of unnecessary resources, the extension of the time of "handover".

Another objective of the invention is to propose a technique for performing quality of service level transfers in order to ensure continuity of service during application execution within a mobile terminal and when traveling. of the last.

Yet another object of the invention is to allow a dynamic update of the quality of service offered to mobile terminals while reducing the time of "handover". 4 Summary of the invention

These objectives, as well as others that will appear later, are achieved by means of a quality of service management method in a cellular network, between at least one mobile terminal and at least one attachment point. .

According to the invention, said network comprises a quality of service management entity and said method comprises, during the establishment of a communication session: a first step of transmission by said management entity, to said mobile terminal, of a set of service classes available for said communication session; a second step of selection by said mobile terminal of a first class of service among said set of available classes of services; a third step of transmission by said mobile terminal of said first selected service class to said management entity; a fourth association step, of a quality of service context, comprising information representative of said first selected service class, to said at least one attachment point.

Thus, the invention proposes a novel and inventive approach to the management of quality of service in cellular networks by introducing the concept of quality of service management entity. This entity is responsible for ensuring the implementation of quality of service in the cellular network by establishing communications with the mobile nodes (terminals) and transmitting quality of service information to them. The purpose of these different transmissions is to determine, in partnership with the mobile nodes, the best class of service available during the establishment phase of the communication session. The determination of the class of service allocated to the mobile is carried out by transmitting to the mobile information on the classes of service available on the network. The mobile selects, from among these classes, the one that suits it (depending on a certain type of application to be executed, for example), then it expresses its choice to the management entity. This entity then associates, in the cellular network, this class of service to the mobile node, through a quality of service context.

Advantageously, said fourth association step comprises a fourth step of transmission of said quality of service context by said management entity, to said at least one attachment point. In this way, the attachment points that support the mobile node are informed of the class of service that has been assigned to that mobile node.

Advantageously, said fourth transmission step comprises at least one transmission of: at least one fourth quality of service information message to said at least one attachment point; and / or at least one fifth service class assignment announcement message to said mobile terminal.

Thus, at the end of the process of establishing a session supporting the quality of service, the management entity notifies all the stakeholders of the session of its allocation decisions. The attachment point receives a message that allows it to reserve bandwidth for the terminal session. This terminal, meanwhile, obtains confirmation from the management entity, the class of service it has and can therefore adapt the operation of its applications so that they take into account the class of service assigned. Advantageously during the course of said communication session, said method implements a dynamic adaptation of said quality of service context by selection by said mobile terminal of a second class among said set of class. The mobile terminal can then take into account the variations in rate and reception parameters to adapt (depending on its movements, for example) its context of quality of service. This adaptation ensures that a service (related to an application) will always be rendered under the terms of a service contract between the management entity and the mobile node. Advantageously, said dynamic adaptation of said quality of service context comprises the following steps:

Comparing said first class of said quality of service context with a current state of said network, delivering information representative ^r of the adequacy of said first class to said current status of said network; - Selection by said mobile terminal, said second class of quality of service, according to the result of said comparison.

The mobile terminal is therefore able to perform measurements of a current state of the network on which it operates. It is also able to compare this current state with the class of service it has negotiated with the management entity. If the class of service is not in adequacy with the state of the network, the mobile terminal can therefore select a suitable class of service.

Advantageously, during a change of attachment point of said mobile terminal to a new point of attachment, said management entity transfers said quality of service context to said new point of attachment, so as to minimize the handover time .

Thus, the management entity is always guarantor of the quality of service available on the network. It is responsible for transferring the information it holds on the context of the quality of service of the terminal to the points of attachment of this terminal. So, as the quality of service context is transferred to attachment points, they do not have the need to establish a renegotiation with the mobile to determine a new context of quality of service. This absence of renegotiation greatly reduces the handover time (also known as "handover time").

Advantageously, said first transmission step comprises at least one transmission of: at least one first class of service class support capability message by said management entity to said at least one attachment point; and / or at least one second quality of service vector advertisement message by said at least one attachment point to said mobile terminal.

The quality of service support capability information is broadcast both at the attachment point and at the mobile terminal. The management entity is responsible for transmitting a message to the attachment point. This message is supported by the attachment point and transmitted as a quality of service support vector to the mobile terminal. The latter therefore knows the capabilities of the network and the point of attachment. In an alternative embodiment, it is also possible for the management entity to directly broadcast a quality of service support vector to the mobile terminal. Advantageously, said first class of service support capability message contains information belonging to the group comprising at least: information indicating whether said at least one attachment point can accept a quality of service request for the class "Conversational In the current point of attachment; information indicating whether said at least one attachment point can accept a Quality of Service request for the "Continuous Flow" class in the current attachment point; information indicating whether the at least one attachment point can accept a Quality of Service request for the "Interactive" class in the current attachment point; information indicating whether said at least one attachment point can accept a Quality of Service request for the "Background task" class in the current attachment point; - Information enabling said at least one attachment point to inform said mobile terminal on its ability to support the quality of service.

This information makes it possible to identify the classes of service supported by the management entity and enable the attachment point to inform the destination terminal of its own ability to take into account classes of services.

Advantageously, said second quality of service vector advertisement message contains information belonging to the group comprising at least: information indicating whether said at least one attachment point can accept a quality of service request for the class

"Conversational" in the current attachment point; information indicating whether said at least one attachment point can accept a Quality of Service request for the "Continuous Flow" class in the current attachment point; - whether said at least one attachment point can accept a Quality of Service request for the "Interactive" class in the current attachment point; information indicating whether said at least one attachment point can accept a Quality of Service request for the "Background task" class in the current attachment point; information enabling said at least one attachment point to inform said mobile terminal on its ability to support quality of service.

In this embodiment, the information transmitted by the point of attachment is directly associated with that transmitted by the entity of management at the point of attachment. This avoids additional calculations at the point of attachment.

Advantageously, said third transmission step comprises at least one transmission of: at least one third service class supply request message to said management entity.

The mobile terminal therefore sends, to the management entity, a request in the form of a message, passing through the attachment point to which it is currently attached. This request is for obtaining a class of service from the management entity. Thus, it is understood that the management entity retains control of the allocation of classes of service. Indeed, if the mobile terminal requires a class of service that is not available, the management entity may deny the assignment.

Advantageously said third service class request request message contains information belonging to the group comprising at least: information representative of said third message; information identifying a data transmission stream allocated by said mobile terminal; an information representative of said first class of service selected by said mobile terminal; information indicating a profile associated with said data transmission stream of said mobile terminal.

This message architecture contains the information necessary for the management entity to accept the assignment of a class of service to a mobile terminal. The information identifying a data transmission stream may, for example, be the identifier of a traffic. The information representing said first class of service may for example be a representation, on 2 bits, of the class chosen by the mobile: "00" for "best effort" to "11" for "Conversational". This information can also be coded on a byte basis, depending on the implementation capabilities of the cellular network.

Advantageously, said fourth quality of service information message contains information belonging to the group comprising at least: identification information of said mobile terminal; information representative of said first selected class of service; an information identifying a data transmission stream, This information enables the attachment point to reserve resources for the mobile terminal. The identifier of the mobile terminal may for example be a local address of the latter within the cellular network. The identifier of the transmission stream can be the source port of the stream.

Advantageously, said fifth service class assignment announcement message contains information belonging to the group comprising at least: information representative of said fifth announcement message; information representative of said first class of service selected. In this case, when the terminal selects a class of service, it is considered that the latter is assigned to it. However, it is quite possible for the quality of service management entity to transmit information representative of another class of service, with the aim either of degrading or of increasing the quality of service provided to the mobile, based on the traffic information the entity has.

Advantageously, said dynamic adaptation of said quality of service context comprises sending: at least one sixth replacement request message, from said mobile terminal, of said first class of said quality of service context by said second class of quality of service at destination of said management entity; and / or at least one seventh confirmation message of said replacement, from said management entity, to said mobile terminal.

The mobile terminal is therefore able to expressly request the management entity to change the class of service. This request can result from traffic measurements made by the mobile terminal. These measures, which the terminal sends to the management entity, can lead the mobile to realize that better classes of services are available. It therefore requires a class change by sending a sixth message to the management entity. If the latter grants the change of class of service, it sends a seventh confirmation message to the mobile terminal. It also sends a message to the point of attachment of the terminal to warn that the class of service of the terminal considered has evolved.

Advantageously, said dynamic adaptation of said quality of service context comprises sending: at least one seventh confirmation message of said replacement, from said management entity, to said mobile terminal when said dynamic adaptation is proposed by said entity quality of service management. Thus, the management entity is also able to perform a modification of the class of service assigned to a mobile. This capability gives the controlling entity the power to control class of service allocations not only to mobile device requests, but also to other considerations, such as, for example, the number of connected terminals in the cellular network, ongoing QoS transfer operations in a mobility domain.

Advantageously, said sixth replacement request message contains information belonging to the group comprising at least: representative information of said sixth message; - information representative of said second class of quality of service; information identifying a data transmission stream of said mobile terminal.

This information enables the controlling entity to identify the origin of the class of service change request request and the required class of service. The identifier of the transmission stream may be the source port of the stream.

Advantageously, said seventh confirmation message of said replacement contains information belonging to the group comprising at least: information representative of said seventh message; information representative of said second quality of service class attributed to said mobile terminal.

The management entity is thus able to make its allocation decisions known to the mobile terminal, by means of information representative of the class of service to which the mobile must comply.

Advantageously, said transfer by said quality of service management entity of said quality of service context to said new attachment point comprises at least one transmission of at least one eighth message containing at least one piece of information representative of said QoS context.

The transfer of the quality of service context is performed by the management entity, at the request of a mobile terminal. Indeed, the mobile terminal continuously performs traffic measurements on the cellular network. These measurements can lead the terminal to identify a better point of attachment for its communication session. In this case, the mobile requests a change of attachment point by a "handover" request. Similarly, the quality of service management entity, through the measurements it receives from the mobile terminals connected to its network can determine a more suitable attachment point for a mobile terminal. The management entity sends an eighth message to the new attachment point of the terminal mobile. If the terminal requests the change, the management entity sends it a change confirmation message. In any case, as long as the procedure for attaching to the new attachment point is not completed, the management entity can advantageously maintain the session on several attachment points for the same mobile to ensure a continuity of mobile terminal service.

Advantageously, said eighth quality of service context transfer message contains information belonging to the group comprising at least: representative information of said eighth message; identification information of said mobile terminal; information representative of a number of streams generated by said mobile terminal; identification information of a data transmission stream of said mobile terminal; at least one information representative of a class of service of said at least one stream associated with said identification information of a data transmission stream.

Thus, the new attachment point receives information enabling it to manage the resource allocation to the mobile terminal even before the latter has actually changed attachment point. This process can significantly reduce the time of "handover" and not have to renegotiate new classes of services with the new point of attachment. The invention also relates to a method for controlling the quality of service of a communication session in a cellular network, between at least one mobile terminal and at least one attachment point.

According to the invention, such a method comprises, during the establishment of said communication session: at least one transmission step, to said at least one terminal mobile, of a set of classes of services available for said communication session; at least one step of receiving a request for a first class of service from said at least one mobile terminal; at least one transmission step to said at least one mobile terminal of a confirmation of the allocation of said first class of service; at least one step of transmitting to said at least one attachment point of information representative of said first class of service assigned to said at least one terminal.

This mechanism makes it possible to establish a communication session supporting the quality of service in a mobility domain.

Advantageously, the control method comprises, during the course of ^• said communication session: - a step of receiving a request for a second class of service from said at least one mobile terminal; and / or a step of sending to said at least one mobile terminal a confirmation of the allocation of said second class of service; Thus, the method is able to maintain the quality of service provided during the communication session by ensuring an evolution of the classes of services allocated to mobile based on available resources.

Advantageously, the method of controlling the quality of service comprises, during a change of attachment point of said mobile terminal to a new point of attachment: at least one intercellular transfer step of said communication session, as a quality of service context to said new attachment point.

The control method therefore makes it possible to carry out a quality of service context transfer to new attachment points in order to reduce the handover time. The invention also relates to an entity for managing the quality of service of a communication session in a cellular network, between at least one mobile terminal and at least one attachment point.

According to the invention, such an entity comprises, during the establishment of said communication session: means for transmitting, to said at least one mobile terminal, a set of classes of services available for said communication session ; means for receiving a request for a first class of service from said at least one mobile terminal; means for transmitting to said at least one mobile terminal a confirmation of the allocation of said first class of service; transmission means to said at least one attachment point of information representative of said first class of service assigned to said at least one terminal.

Advantageously, this quality of service management entity comprises, during the course of said communication session: means for receiving a request for a second class of service from said at least one mobile terminal; means for transmitting to said at least one mobile terminal a confirmation of the allocation of said second class of service; Preferably, this quality of service management entity comprises, during a change of point of attachment of said mobile terminal to a new point of attachment: - means of intercellular transfer of said communication session, under the form of a quality of service context to said new attachment point.

This management entity therefore has all the capabilities to manage communication sessions integrating quality of service. This entity can be located on an existing communication network. The invention also relates to a method of routing the quality of service of a communication session in a cellular network, between at least one mobile terminal and at least one quality of service management entity.

According to the invention, such a method comprises, during the establishment of said communication session: at least one reception step, from said management entity of a set of classes of services available for said communication session; at least one transmission step, to said at least one mobile terminal, of said set of service classes available for said communication session; at least one step of receiving, from said management entity information representative of a first class service rating ^• said at least one mobile terminal. This routing method enables the cellular network to support the communication sessions integrating the quality of service. It allows the transfer of quality of service information between the mobile terminals and the quality of service management entity of a mobility domain.

Advantageously, this method of routing the quality of service comprises at least one step of receiving at least one information of a quality of service context associated with said at least one mobile terminal, during an intercell transfer of said session. Communication.

Thus, the routing method is able to take into account and anticipate the "handover" during a handover of a mobile terminal. The invention further relates to a point of attachment of a cellular network, routing a communication session between at least one quality of service management entity and at least one mobile terminal.

According to the invention, such an attachment point comprises, during the establishment of said communication session: reception means, coming from said at least one communication entity; managing a set of service classes available for said communication session; means for transmitting, to said at least one mobile terminal, said set of classes of services available for said communication session; receiving means from said at least one information management entity representative of a first class of service assigned to said at least one mobile terminal.

In a preferred manner, this point of attachment of a cellular network, comprises means for receiving at least one information of a quality of service context associated with said at least one mobile terminal, during an intercell handover of said communication session.

This attachment point of a cellular network is capable of routing the quality of service information of the communication sessions. It is also capable of receiving QoS contexts of mobile terminals from management entities to minimize handover time during a handover.

The invention also relates to a method of taking into account the quality of service of a communication session in a cellular network, between at least one quality of service management entity and at least one attachment point.

According to the invention, such a method comprises, during the establishment of said communication session: at least one step of receiving, from said at least one attachment point, a set of classes of services available for said communication session; at least one selection step, from among said set of available service classes, of at least a first class of service; at least one step of sending, to said at least one management entity, information representative of said first class of selected service; at least one step of receiving, from said at least one management entity, information representative of a confirmation of the allocation of said first selected class of service. Advantageously, this method of taking into account the quality of service of a communication session includes, during the course of said communication session: a step of dynamic adaptation of a quality of service context by selecting a second one of said set of service classes available for said communication session; and / or a step of transmitting a request for said second class of service to said at least one quality of service management entity; and / or a step of receiving from said at least one quality of service management entity a confirmation of the allocation of said second class of service;

This method of taking into account the quality of service makes it possible to effectively use the information transmitted by the attachment points of a cellular network and by the management entity in charge of the quality of service in the mobility domain.

The invention also relates to a mobile terminal capable of taking into account the quality of service of a communication session in a cellular network, between at least one quality of service management entity and at least one attachment point. According to the invention, such a terminal comprises, during the establishment of said communication session: means for receiving a set of classes of services available for said communication session from said at least one attachment point; selection means, among said set of classes of services available, at least one first class of service; means for transmitting information representative of said first selected class of service to said at least one management entity; means for receiving information representative of a confirmation of the allocation of said first selected class of service from said at least one management entity.

Advantageously, this mobile terminal comprises, during the course of said communication session: means for dynamically adapting a quality of service context by selecting a second class from among said set of classes of services available for said session of communication; means for transmitting a request for a second class of service ^v destination of said at least one quality of service management entity; means for receiving a confirmation of the allocation of said second class of service from said at least one entity of. quality of service management;

Thus, such a terminal is able to establish communication sessions supporting quality of service in a mobility domain, in partnership with the attachment points and the quality of service management entity.

The invention also relates to computer programs implementing the method of managing the quality of service as described above.

The invention also relates to computer programs implementing the method of controlling the quality of service as described above.

The invention also relates to computer programs implementing the method of routing the quality of service as described above.

The invention finally relates to computer programs implementing the method of taking into account the quality of service as described above. The invention also relates to computer program products downloadable from a communication network and / or stored on a computer readable medium and / or executable by a microprocessor,

A first type of program product according to the invention comprises program code instructions for executing the control method when it is executed on a computer.

A second type of program product according to the invention comprises program code instructions for executing the steps of the routing method, when executed on a computer. A third type of program product according to the invention comprises program code instructions for performing the steps of the quality of service method when executed on a computer.

5 List of figures

Other features and advantages of the invention will emerge more clearly on reading the following description of a preferred embodiment, given as a simple illustrative and nonlimiting example, and the appended drawings, among which: FIG. 1 presents a sequence diagram of the message exchanges between the components of a cellular network according to the invention; FIG. 2 is a sequence diagram of message exchanges during the entry of a mobile node into a micro mobility domain according to the invention; Fig. 3 is a sequence diagram describing the dynamic update of the QoS of a mobile node; FIG. 4 shows a "handover" scenario of a mobile node in a micro mobility domain; Figure 5 describes the functional architecture of a micro mobility domain; Figure 6 depicts the overall process of transferring quality of service between two attachment points of a micro mobility domain; FIG. 7 describes the hardware architecture of the quality of service management entity of a micro mobility domain; Figure 8 describes the hardware architecture of an attachment point according to the invention. ; Figure 9 depicts the hardware architecture of a mobile terminal ^'of the invention.

6 Detailed description of the invention 6.1 Recall of the principle of the invention

6.1.1 Definitions of acronyms used - QMM is the manager of QoS and Mobility in his field.

Micro mobility domain: which consists of a QMM, a set of PAn attachment points. A micro mobility domain can be connected to the Internet.

MIQ: Database to maintain network load information and mobile service classes visiting this domain.

6.1.2 Principle

The invention therefore proposes a mechanism for reducing the handover time for an application that requires the quality of service and optimize the use of resources in the access networks. The general principle of the invention relies on the use of a quality of service management entity within the cellular network.

To achieve such a mechanism it is also necessary to introduce a dynamic adaptation of the application. This adaptation is implemented using a solution of "Q3M"("QoS and Micro Mobility Management" for "Quality Management Service and Micro Mobility"). This method consists in initiating a communication session supporting the quality of service and dynamically updating the class of service assigned to the mobile, without interrupting the data transfer, which is a critical parameter for the applications, especially in real time. The "Q3M" solution also allows control the handover with QoS without having to renegotiate the class of service.

The functional architecture of a cellular network that incorporates QoM (QoS and Mobility Manager) quality management service entity (QoS and Mobility Manager for Quality of Service and Micro Mobility Manager) is described in the section 6.4.

6.1.3 Benefits

The benefits of QMM QoM solution are as follows: - The mobile node is informed of the supported classes of service, indicating its chances of acceptance by the network for any new requests for service. QoS. This allows to minimize the likelihood of rejection of the request QoS and minimize exchange trading posts de- ^• QoS and thus reduce or even cancel the handover time; - The mobile node can adapt the QoS level since the QMM can offer the source a better class of service in another access router or if the network becomes less loaded. ;

The solution is more flexible since the mobile node participates in the choice of the QoS level. Indeed, since it has information about the state of traffic and / or network congestion, the mobile terminal is able to make prior choices as to the required classes of service; Q3M provides dynamic QoS management;

The NM has the ability to use multiple profiles according to the requirements of the applications. For example, for a videoconferencing application, it is necessary to use a profile that has a high priority. On the other hand, for a download application, a Best Effort class is enough;

Q3M provides in-band signaling between the QMM and the mobile node by adding an option in the packet header. The goal is to integrate QoS requests into the flow and alert the QMM in case the quality is insufficient for the application; Subsequently, the general case of setting up, updating and "handover" procedure for a mobile node in connection with a quality of service management entity "QMM" in the part of the Q3M protocol. It is clear however that the invention is not limited to this particular application, but can also be implemented in many other fields, and for example in the case of a non-mobile communication network and more generally in all where the objectives listed below are interesting.

6.2 sequence of message exchanges between the components of a cellular network, in connection with the "QMM"

With reference to FIG. 1, the general principle of the message exchange leading to the establishment (P1), the hold (P2) and the handover procedure (P3) in connection with the QMM is presented. 30, according to the management method ¹ 'quality of service. In this embodiment, the quality of service management entity "QMM" announces (1) at the attachment points (20, 21, ...) their ability to support the service classes in a vector of service. "QoS". This vector is a triplet which indicates, depending on the load of the network (for example depending on the load of the attachment points), whether the network can accept new traffic with for example one of these three classes of services other than the best effort class (conversational, continuous flow, interactive). This information minimizes the exchange of messages between the NM (mobile node) and the QMM to negotiate a quality of service. This announcement (1) is made by means of the QoS capability message used by the QMM to inform the attachment points on the classes of services that it can accept according to the resources available at the moment. This message may, for example, contain at least one default service class {Best Effort}.

The attachment points (20, 21, ...) then use the QoS vector, sent by the QMM (30), to broadcast (2) the information to the mobiles (10) they serve. This broadcast (2) is performed by the message QoS vector announcement (QoSV). This message, for example, contain at least the flag of the best effort service class that is available

At the time of registration in a micro mobility domain, the mobile node (NM) negotiates with the QMM 30 a class of service. This negotiation is carried out by the message "QoS-Req"("QoSRequest" for "Quality of Service Request"). This message is used by the mobile to send (3) his profile to the QoS manager. The QoS profile contains, for example, the requested class of service. This message may contain, for example, at least the stream profile; The NM 10 also transmits quality measurements to the QMM 30 and may request to change its class of service if the quality falls below a threshold configured dynamically by the QMM 30 (depending on the network load). The QMM 30 transmits (4) the result of the service class calculations' ¹ to the attachment points (20, 21, ...). These results come from the measurements made by the mobile nodes. The transmission 4 is performed by the message "QoS information" (for "Information on the quality of service"). This message allows the QoS manager to inform the attachment point of the assigned service class to the new NM traffic. This message contains for example: source address, source port, destination address, destination port, service class, and action (add or remove).

NM 10 continuously monitors the QoS vector. When he wants to change a class of service, he checks the QoS vector and if the requested class is validated. This verification is performed by receiving (5) the message "QoS-Res" ("QoS Response" for "Quality of Service Response") which gives the mobile a response to its QoS request. This message contains for example the identifier of the flow and the class of service assigned by the QMM and this flow.

During the flow (P2) of the session, the NM 10 can ask the QMM 30 to modify its class of service, either because it performs measurements that allow it to conclude that better classes of service are available, or because a new application requires a new type of service. The "QU"("QoSUpdate" for "Quality of Service Update") is then used (6) by the NM 10 to update the service class of a flow it generates. This message contains for example the identifier of the flow, the current service class and the requested class of service. The QA message (QoS Acknowledgment for QoS acceptance) is then used (7) by the QMM 30 to give a response to the "QU" message. The QoS manager sends (7) this message to the mobile. This message contains for example the identifier of the stream and the new class of service.

It is also possible, in a complementary embodiment, that the QMM offers the mobile to change its class of service with its point of attachment to improve its quality of service.

During his visit, and the view of the measures carried out, the MV 10 can ask to change the point of attachment, or in the area of ^'micro mobility being or inter-domain. In this case, the mobile node 10 sends (8) a message "HO-Req"("HandoverRequest" for "Relay Pass Request") to the QMM 30. This last transfer (9) then the information to the new point mobile attachment in the form of a "QT" message - ("QoS Transfer" for "Quality of Service Transfer"). In order to anticipate the handover, the QMM 30 is responsible for transferring the mobile service classes to the new attachment point 21. This message contains, for example: the source address, destination address, source port, port destination, class of service and action (add or remove). When this transfer is performed, the QMM 30 responds to the NM 10 by transferring (11) a message HO-Res.

In an alternative embodiment, it is of course quite possible to determine more than three classes of services available. The three classes mentioned only correspond to examples relating to certain types of applications available on mobiles.

In another embodiment, it is also possible to ensure that the attachment points transmit the load measurement information to the QMM. Indeed, it is quite conceivable that the point of attachment is able to know his load and that he can transmit this information to the QMM.

6.3 Detailed Description

Next, a particular embodiment of the quality of service management protocol is presented. In this embodiment, the following assumptions are made:

There is no postulate on the topology of the packet network (hierarchical topology or not).

A PA belongs to a single area of micro mobility. A PA is associated with a list of neighbor PAs. A PA is said to be neighbor to another PA, according to criteria specific to the operator.

The QMM periodically calculates its available resources and the classes of services it can support at each point of attachment.

The QMM periodically sends messages to the PAs in its domain containing parameters signaling support for the Q3M solution.

The PA periodically broadcasts a QoS vector to help the MN to choose the class of QoS to solicit.

Upon registration with the QMM, and whenever desired, the mobile terminal NM negotiates a class of service with the QMM. The quality of service requested is then negotiated according to the resources available within the network and the mobile subscription.

The QMM checks the availability of resources and the compliance of the request with the user's subscription. It can, if necessary, modify the requested class and send back to the mobile a response including the level of the proposed QoS. If no level of quality of service is requested by the terminal when it is registered with the

QMM is the class of service stored in the QMM database that becomes the default class.

Once the QoS negotiation phase is completed, the QMM informs the PA of the class of service attributed to the mobile.

The NM can use different classes of service at the same time, a class for each application.

6.3.1 Entry scenario of a mobile node in an O3M micro mobility domain

In connection with FIG. 2, the input scenario (P1) of a mobile node 10 in a Q3M micro mobility domain is presented:

The QMM 30 informs (1) the PA 20 on the classes of services that it can announce to the mobiles it serves - Reception (2) by the NM 10 of a router advertisement containing parameters signaling the support of the Q3M protocol and the QoS vector.

The NM 10 registers with the QMM 30 by issuing (3) a registration request which contains its QoS profile and the level of the requested QoS ^h via the QoS-Req message. - The QMM 30 consults (4) its MIQ 40 database ("Monitor information of QoS" for "Quality of Service Control Information"), authenticates the request, and collects load information from its attachment point and then executes an admission control algorithm. - The QMM 30 signals (5) PA 20 the class of service assigned to the new mobile node.

The QMM 30 acknowledges the registration request with a QoS-Res acknowledgment message.

The QMM 30 provides (7) to the NM 10 the list of PAs adjacent to its current PA, thus making it possible, if that were to happen, to dynamically update the quality threshold which triggers a handover procedure (cf 6.3.3). .

6.3.2 Scenario of dynamic QoS update

In connection with Figure 3, we present the scenario of the dynamic update (P2) of the QoS, following the vector announcements: The QMM 30 sends (1) PA 20 the access network capability to accept a QoS request for mobiles attached with this PA 20;

NM 10 receives (2) the QoS vector;

If the bandwidth is below a threshold B1 or the delay is less than a threshold D1, a flag of the QoS vector is then set to 0, which indicates to the mobile node 10 that it can improve its QoS level. The NM 10 sends

(3) then a QU message to ask to change his class of service;

The QMM 30 consults (4) its MIQ database 40, to do admission control of the mobile node 10; The QMM 30 signals (5) to the PA 20 the update of the class of service assigned to the mobile node 10;

The QMM 30 acknowledges (6) the update request with an acknowledgment message QA;

The NM 10 confirms (7) the updating of the class of service; 6.3.3 Handover scenario of a mobile node in an O3M micro mobility domain

With reference to FIG. 4, the handover scenario (P3) of a mobile node 10 in a Q3M micro mobility domain is presented:

The NM 10 continuously controls (1) its binding quality with its current attachment point (aPA); when the quality falls below a quality threshold S1 (configured by the QMM 30), the NM 10 collects (2) the quality measurements of the links with the attachment points adjacent to its current PA 20;

The NM 10 sends (3) the collected measurements in a handover request to the QMM 30. The handover request message is sent with the highest priority (HO-Req); the QMM 30, consults (4) its MIQ 40 database and the user profile and analyzes the measurements;

The QMM 30 executes (5) an admission control algorithm to select the target PA (nPA); The QMM 30 sends (6) a response to the NM 10 to give the address of the new PA (21) and the assigned service class;

The QMM 30 sends (7) the QoS context to the new nAP 21 attachment point; - NM 10 attaches (8) to the new PA (nPA) 21;

The NM 10 issues (9) a handover confirmation message to the QMM

30 ;

The QMM 30 updates (11) its MIQ database (the list of mobiles in its domain, the quality of service of each NM, the load of the network, etc.);

The QMM 30 acknowledges (12) the confirmation message;

The QMM 30 informs (13) the old attachment point (aPA) 20 that the

NM 10 has changed its point of attachment;

The former attachment point (aPA) sends (14) a QoS ratio of NM 10 to QMM 30;

The QMM 30 updates (15) its MIQ database 40;

The QMM 30 sends (16) to the mobile node 10 the new neighbor list of its current attachment point and the quality thresholds (Sl and S2);

The mobile node 10 continuously controls (17) its link quality with its new AP (nPA) 21 and the vector value of QoS;

As can be seen, this handover procedure makes it possible to completely eliminate the service interruption time due to a change of attachment point. Indeed, as the mobile is the initiator of change and has information about the state of the network, it is able to anticipate any risk of service interruption and thus maintain the continuity of its service .

6.4 Example of implementation

6.4.1 Functional architecture of the implementation

With reference to FIG. 5, the functional architecture of a micro mobility domain in which a QMM 30 is implemented is presented. - The QoS and mobility manager (QMM) 30: it plays the role of mobility manager in NCHMIPvό and in addition he is the manager of the QoS in the field of micro mobility 301. The QMM 30 is the head of the admission control and is in charge of making the link between the QoS policies in the networks 50 external 60 (Internet for example), 70 (home network, for example in another area of micro mobility 701) and its own micro mobility area 301. As well as the selection of the new access router (APl 20, AP2 21 , AP3 22) during the handover procedure while taking into account the profile of the mobile node 10 and the network load. The structure of the management entity is illustrated schematically in FIG. 7. It comprises a memory M 71, and a processing unit 70 equipped with a microprocessor μP, which is controlled by a computer program (or application) Pg 72. The processing unit 70 receives, via an input network interface module E 73, requests and / or customer responses 74, which the microprocessor μP processes, according to the instructions of the program Pg 72, for generate commands and / or responses 76, which are transmitted via a network output interface module S 75.

The QoS Access Router (QoS Access Router) 20, 21, 22, 23: This is an access router that connects to the IP-level access network. is responsible for controlling mobile outgoing traffic (QoS settings). In our implementation QARs are attachment points (APs).

PA (20, 21, 22, 23): it is an access point which ensures the attachment of the mobile node to the micro mobility domain (radio level). Each AP is connected to an IP access router. The structure of an attachment point is illustrated schematically in FIG. 8. It comprises a memory M 81, and a processing unit 80 equipped with a microprocessor μP, which is controlled by a computer program (or application). Pg 82. The processing unit 80 receives, via an input network interface module E 83, requests and / or customer responses 84, that the microprocessor μP processes, according to the instructions of the program Pg 82, to generate commands and / or responses 86, which are transmitted via a network output interface module S 85.

MIQ 40: Database to maintain network load information and mobile service classes visiting this domain. The

MIQ 40 is directly related to QMM 30.

NM 10: This is a mobile node that can choose a profile to use for an application that has QoS requirements. The structure of a mobile node is illustrated schematically in FIG. 9. It comprises a memory M 91, and a processing unit 90 equipped with a microprocessor μP, which is controlled by a computer program (or application). The processing unit 90 receives, via an input network interface module E 93, requests and / or customer responses 94 ¹ , which the microprocessor μP processes, according to the instructions of the program Pg 92, for generating commands and / or responses 96, which are transmitted via an S 95 network output interface module. 6.4.2 Initialization in a Q3M-supporting domain, each attachment point belongs to a single QMM and has a list of neighboring attachment points. - The list of attachment points adjacent to an attachment point is saved in a database that also contains the profiles of the mobiles that are visiting in its domain, as well as information about the network load per point of interest. attachment (PA). The attachment points announce the support of Q3M by periodically broadcasting an information packet identical to that of HMIPvό with a MODE field (reserved) indicating the Q3M solution (in the implementation, this field equal to the value 2 to define the control of QoS and micro mobility). In this message, the attachment points also signal their ability to support a new QoS request (a flag for each class). When a mobile node moves into a new Q3M-aware domain, it receives an attachment point announcement with the Q3M option and the service class flag.

The following paragraphs describe the implementation formats of the messages received and sent by the QMM.

6.4.3 The QoS Vector Announcement Message

The format of the QoS vector announcement message is as follows:

Type Length Dist C S I N I B I R M I I T P V Mode

Valid life time

Global EP address faith Q3M

In which :

Type (1 byte): it indicates the type of message (ICMPvβ)

Length (1 byte): indicates the length of the option in bytes

Dist (4 bits): This field indicates for the destination the distance (in number of nodes) of access routers.

C (1 bit): This flag indicates if the corresponding Q3M router can. accept a QoS request for the Conversational class in the current attachment point.

S (1 bit): This flag indicates whether the corresponding Q3M router can accept a QoS request for the Streaming class in the current attachment point.

N (1 bit): This flag indicates whether the corresponding Q3M router can accept a QoS request for the Interactive class.

B (1 bit): This flag indicates whether the corresponding Q3M router can accept a QoS request for the Background class in the current attachment point.

R (1 bit): it indicates the basic mode of mobility

M (lbit): this field indicates the mode with extension

I (1 bit): This field indicates that the NM can use the regional address RCoA as the source address.

T (1 bit): This field indicates that the NM can hide its LCoA and use the RCoA address to be contacted by a correspondent. P (lbit): This field is used to indicate that the NM should use the RCoA as the source address.

V (1 bit): it indicates the use of reverse tunneling Mode (2 bit): it is a reserved field (not used) in the HMIPvβ protocol, and is used so that the PA can inform the mobiles that it supports the Q3M solution (mode = 2). - Valid life time: This field indicates the validity time of the QMM address (RCoA)

6.4.4 The setup messages of a session QoS is described here the establishment of message format of a QoS session ^'in between a mobile node and an attachment point. To do this, we use three messages: QoS-Req, QoS-Res and QoS Information. 6.4.4.1 The OoS-Req message

When the mobile node registers with its QMM, it sends the profile for use in an option of the Binding Update message of the traditional IP mobile (this is the QoS-Req message).

Option Type

Option Length prefix length Sequence Number

Lifetime

VCOA

Sub-Option Sub-Option Type Length Flow Id required class

QoS profile

Typical option (1 byte): 198 (Binding Update).

Option Length (1 byte): II indicates the length of the option in bytes without counting the first two fields.

Prefix Length (1 byte): II is initialized to zero during transmission and ignored when receiving.

Sequence Number (2 bytes): It is used by the receiving node to sequence the update messages and by the sender for the association of the updates with the Binding Acknowledgments in return. The mobile node must use a larger sequence number than the sequence number used in the previous update message sent to the same destination.

Lifetime (4 bytes): II indicates the number of seconds remaining before the

Binding Update expires. - VCOA (16 bytes): This field contains the new nVCOA virtual address of the mobile node.

Sub-Option Type (1 byte): 111. This field indicates that this is a session request with QoS (the QoS-Req message).

Sub-Option length (1 byte): it indicates the length of sub-option in byte not counting the first two fields.

Flow Id (1 byte): It is an identifier of the traffic allocated by the mobile, it is this numerical identifier which must be used between the manager of the

QoS and the mobile node to differentiate the traffic of the same mobile.

This reduces the size of the update packets since a numeric identifier (between 1 and 128) requires one byte while an 8-character name needs 8 bytes. If this field is zero, it is ignored. This identifier is mandatory for updating the service class of a traffic. required class (1 byte): This field indicates the class of service requested by the mobile.

QoS Profile: This is the profile of the mobile node that contains information about the quality of service requested and the type of mobile subscription. As well as traffic specification parameters (see §8.5).

6.4.4.2 The QoS-Res message The QoS manager acknowledges the registration request with an acknowledgment message (this is the QoS-Res message). The QoS Manager encapsulates its response in an Acknowledgment binding message option and sends it to the mobile.

Option Type

Option Length Sequence Number

Lifetime

Refresh

Sub-Option Type Sub-Option length FIow Id. Assigned class

Option Type (1 byte): 7. This is an Acknowledgment Binding. Option Length (1 byte): The length of the option

Status: II indicates the result of the Binding Update. A value less than 128 indicates that it is accepted and a higher value indicates that it is rejected. Sequence Number: It is copied from the Acquired Binding Update. Thus, the mobile node may match the received Binding Acknowledgment with one of its issued Binding Updates. Lifetime: If the response is positive, it indicates the amount of time in seconds that the receiving node keeps the mobile node's entry in its Binding cache. Otherwise, it is undefined.

Refresh: II indicates the time interval in seconds after which the mobile node must send a new Binding update to refresh its Binding.

Sub-Option Type (1 byte): 112. This is the new QoS-Res message suboption.

Sub-Option Length (1 byte): II indicates the length of the suboption in bytes without counting the first two fields.

Assigned class (1 byte): This field indicates the class of service assigned to the mobile request. 6.4.4.3 The QoS Information message

The QMM is the entity that decides to which point of attachment the mobile should move. The QMM informs the attachment point of new streams to apply the class of service on this traffic. This message contains the source address, the service class assigned by the QMM, and the source port of this stream. This makes it possible to apply the QoS policy on the traffic that passes through this point of attachment.

The QI message is sent through an IPv6 socket.

MN LCoA: this is the local address of the mobile node - Class (1 byte): this field indicates the class of service of the new ;. application that uses the source port x

Source port x (1 byte): the source port of the stream

6.4.5 Mobile Profile:

In order to allow the mobile node to request a QoS class from the QMM, a QoS profile is used which specifies the traffic and contains the identity of the mobile node and the type of its subscription. This profile contains the following information:

QoS class: translates the class of service requested by the mobile

(Conversational, Continuous Flow, Interactive and Background Task). - Stream identifier: corresponds to the identifier of the stream and used by the mobile and the QMM to update the QoS class.

Source address: This is the mobile node address

Destination Address: This is the address of the correspondent.

Source port: (for example, 150) - Destination port: (for example, 1100)

Nature of service: There are two modes of service, both connected and unconnected. Type of traffic: gives indications on the types of traffic the different types of traffic are: o Guarantee (constant flow) o Non- Guaranteed (variable flow) o Variable flow with guarantee of a minimum flow.

Traffic characteristics: It indicates whether the service is point-to-point or point-to-multipoint.

Minimum Bandwidth: The minimum bandwidth for this application. - The variation of delay or jitter: characterizes the difference in transfer time for successive communications between a transmitter and a given receiver.

Reliability: reflects the average error rate of different media and communication equipment. - The bandwidth corresponds to the possible bitrate between two endpoints. It is limited by the throughput of the physical links crossed, but also by the competing flows and the capacity of the equipment. Customer class: translates the customer class (Gold, Silver, and Bronze). Operator ID: corresponding to the identifier of the operator who provided the subscription to the user.

6.4.6 Dynamic class of service control 6.4.6.1 The OR message

In a Q3M-supported domain, a mobile node continuously monitors the quality of service offered by the network and the QoS vector ads. If the quality degrades below a threshold Q1 configured dynamically by the QoS manager and the QoS vector informs it that it can improve its class of service, the mobile node sends a request to update the class of service . The QMM can also perform this operation without the intervention of the mobile node by directly proposing the change of class of service. The QoS update request is an IPv6 packet with a new QoS Update destination option. The message has the following form:

Option Type (1 byte): 14. This field indicates that this is a QoS Update option (QU message). - Length option (1 byte): indicates the length of the option in bytes without counting the first two fields. required class (1 byte): This field indicates the class of service requested by the mobile. (C for Conversational, S for Streaming and I for Interactive) - Flow Id (1 byte): this is the identifier of the stream whose class of service is to be updated. 6.4.6.2 The OA message

QMM must continually monitor available resources for optimal utilization and provide a mobile node with an opportunity to improve its class of service. To do this we run a periodic function that calculates the resources available every two seconds (configurable).

Upon receipt of a message QU, the QoS manager returns its update response to the mobile node specifying the new class of service, this is the QA message. In addition, the QoS manager informs the attachment point of the mobile of this update to accept this traffic with the new class of service.

The mobile node receives the response and uses the value of the new class field to mark subsequent packets of that stream. The message has the following form:

Option Type | Length option

New class Prefix Length Sequence Number

Life time Flow Id.

Option Type (1 byte): 15. This field indicates that it is a QU message.

New class (1 byte): This field indicates the class of service assigned to the mobile.

6.4.7 Handover control with QoS

This section describes the "handover" control messages with QoS support.

6.4.7.1 Level 2 quality control

When entering a Q3M micro mobility domain, the mobile sends a Binding Update to the QMM with suboption 110 (information on APs) indicating the SSID of the current attachment point. The QMM sends the mobile node the list of neighboring access points. If the radio quality is less than Sl, the mobile node collects quality measurements with neighboring access points and ... returns them to its QMM. However, the structure of the MIPL code requires the use of a sub-option of a certain type once and only once in the package.

Thus, using the new PA information suboption to describe multiple APs may be problematic because the suboption is repeated as many times as there are neighboring attachment points. To solve this problem and in order not to destabilize the code, the Q3M protocol defines a new structure of the suboption 110:

...

AP Identify SSID Length

SSID

AP n

SSID

The size of this packet is therefore 4 bytes + 12 * N where N represents the number of attachment points between 1 and 6 max (thus 76 bytes maximum) 6.4.7.2 The control of the thresholds of handover

The mobile is able to permanently know the link quality with its current PA. It should compare it to a Sl threshold that is dynamically configured by the QMM based on the attachment point load and the mobile node's class of service level. The threshold is sent to the mobile via a Binding Request + a sub-option 13 Control Threshold. A second threshold S2 is also configured by the QMM, which is the threshold below which the mobile will choose its own recipient PA.

6.4.7.3 The transfer QoS message The mechanism of anticipation of the handover realized by the QMM 30 is described in relation with FIG.

When moving, the mobile node 10 measures the quality of its link with its attachment point 20 and its neighboring attachment points (21 ', 22). When the mobile considers that it can obtain a better class of service, it sends (1) a message HO-Req to the QMM 30.

The QMM 30 is the entity that decides to which attachment point neighbor the mobile 10 is to move. As such, the QMM 30 anticipates the handover and sends (3) a message QT (QoS transfer) to the new PA (22) to optimize the handover time, this message contains the QoS context of the mobile 10. Before the mobile 10 focuses on the new PA 22, the QoS context is already established. While the mobile is doing its handover, as long as it has not sent a Binding Update via its new PA 22, the QMM 30 bicaste (2) packets towards the mobile by adding an entry in the association table to the new LCoA. This minimizes the loss rate during the handover procedure (4). The QT message is sent by an IPv6 socket:

MN LCoA: this is the local address of the mobile node;

Nb flow (1 byte): the number of streams generated by the mobile node; Class x (1 byte): This field indicates the class of service of the stream that uses the source port x;

Source port x (1 byte): the source port of the stream;

Claims

A method for managing the quality of service in a cellular network between at least one mobile terminal and at least one attachment point, characterized in that said network comprises a quality of service management entity, said method comprises, during the establishment of a communication session: a first step of transmission by said management entity, to said mobile terminal, of a set of classes of services available for said communication session; a second step of selection by said mobile terminal of a first class of service among said set of available classes of services; a third step of transmission by said mobile terminal of said first selected service class to said management entity; a fourth association step, of a quality of service context, comprising information representative of said first selected service class, to said at least one attachment point.

A method of managing the quality of service according to claim 1, characterized in that said fourth association step comprises a fourth step of transmitting said quality of service context by said management entity, to said at least one point of service. attachment.

A quality of service management method according to claim 2, characterized in that said fourth transmission step comprises at least one transmission of at least one fourth quality of service information message to said at least one point of attachment; and / or at least one fifth service class assignment announcement message to said mobile terminal.

4. Quality of service management method according to any one of claims 1 and 3, characterized in that, during the course of said communication session, said method implements an adaptation. dynamic said context quality of service by selection by said mobile terminal of a second class among said set of class.

A quality of service management method according to claim 4, characterized in that said dynamic adaptation of said quality of service context comprises the following steps:

Comparing said first class of said quality of service context with a current state of said network, providing information representative of the adequacy of said first class to said current state of said network; Selection by said mobile terminal of said second class of quality of service, according to the result of said comparison.

6. Quality of service management method according to any one of claims 1 to 5, characterized in that during a change of attachment point of said mobile terminal to a new point of attachment; said management entity transfers said quality of service context to said new attachment point, so as to minimize the handover time.

7. Quality of service management method according to any one of claims 1 to 6, characterized in that said first transmission step comprises at least one transmission of: - at least a first message class support capacity service by said management entity to said at least one point of attachment; and / or at least one second quality of service vector advertisement message by said at least one attachment point to said mobile terminal.

8. QoS management method according to any one of claims 1 to 7, characterized in that said third transmission step comprises at least one transmission: at least a third request message supply of a class of service to said management entity.

9. Quality of service management method according to claim 3 and any one of claims 4 to 8, characterized in that said dynamic adaptation of said quality of service context comprises a transmission of: at least one sixth message requesting replacement, from said mobile terminal, of said first class of said QoS context by said second class of quality of service to said management entity; and / or at least one seventh confirmation message of said replacement, from said management entity, to said mobile terminal.

10. Quality of service management method according to claim 3 and any one of claims 4 to 8, characterized in that said dynamic adaptation of said quality of service context comprises a transmission of: at least one seventh confirmation message of said replacement, from said management entity, to said mobile terminal when said dynamic adaptation is proposed by said quality of service management entity.

The quality of service management method according to claim 5 and any one of claims 6 to 10, characterized in that said transfer by said quality of service management entity of said service quality context to said new point. attachment comprises at least one transmission of at least one eighth message containing at least one information representative of said context of quality of service.

12. A method for controlling the quality of service of a communication session in a cellular network, between at least one mobile terminal and at least one attachment point, characterized in that it comprises, during the establishment of said communication session: at least one transmission step, to said at least one mobile terminal, of a set of classes of services available for said communication session; at least one step of receiving a request for a first class of service from said at least one mobile terminal; at least one transmission step to said at least one mobile terminal of a confirmation of the allocation of said first class of service; at least one step of transmitting to said at least one attachment point of information representative of said first class of service assigned to said at least one terminal.

13. A method for controlling the quality of service, according to claim 12, characterized in that it comprises, during the course of said communication session: at least one step of receiving a request of a second class of ^f service from said at least one mobile terminal; and / or at least one transmitting step to said at least one mobile terminal of a confirmation of the allocation of said second class of service;

14. QoS control method according to any one of claims 12 and 13, characterized in that it comprises, during a change of attachment point of said mobile terminal to a new point of attachment at least one handover step of said communication session, in the form of a quality of service context to said new attachment point.

15. QoS management entity of a communication session in a cellular network, between at least one mobile terminal and at least one attachment point, characterized in that it includes, when establishing said communication session: means for transmitting, to said at least one mobile terminal, a set of classes of services available for said session of communication; means for receiving a request for a first class of service from said at least one mobile terminal; means for transmitting to said at least one mobile terminal a confirmation of the allocation of said first class of service; means for transmitting to said at least one point of attachment of information representative of said first class of service assigned to said at least one terminal.

16. QoS management entity according to claim 15 characterized in that it comprises, during the course of said communication session: means for receiving a request for a second class of service from said to minus a mobile terminal; means for transmitting to said at least one mobile terminal a confirmation of the allocation of said second class of service;

17. QoS management entity according to any one of claims 15 and 16 characterized in that it comprises, during a change of point of attachment of said mobile terminal to a new point of attachment: - intercell handover means of said communication session, in the form of a quality of service context to said new attachment point.

18. A method for routing the quality of service of a communication session in a cellular network, between at least one mobile terminal and at least one quality of service management entity, characterized in that it comprises, when establishing said communication session: at least one reception step, from said management entity of a set of service classes available for said communication session; at least one transmission step, to said at least one mobile terminal, of said set of service classes available for said communication session; at least one reception step, from said information management entity representative of a first class of service allocated to said at least one mobile terminal.

19. Quality of service routing method according to claim 18, characterized in that it comprises at least one step of receiving at least one information of a quality of service context associated with said at least one mobile terminal, when an intercellular transfer of said communication session.

20. The attachment point of a cellular network, routing a communication session between at least one quality of service management entity and at least one mobile terminal, characterized in that it comprises, when setting up said communication session: receiving means from said at least one management entity of a set of service classes available for said communication session; means for transmitting, to said at least one mobile terminal, said set of classes of services available for said communication session; receiving means from said at least one information management entity representative of a first class of service assigned to said at least one mobile terminal.

21. attachment point of a cellular network, according to claim 20, characterized in that it comprises means for receiving at least one information of a quality of service context associated with said at least one mobile terminal, during an intercell transfer of said communication session.

22. Method of taking into account the quality of service of a session of communication in a cellular network, between at least one quality of service management entity and at least one attachment point, characterized in that it comprises, during the establishment of said communication session: at least one a step of receiving, from said at least one attachment point, a set of service classes available for said communication session; at least one selection step, from among said set of available service classes, of at least a first class of service; at least one step of sending, to said at least one management entity, information representative of said first selected class of service; at least one step of receiving, from said at least one management entity, information representative of a confirmation of the allocation of said first selected class of service.

23. A method of taking into account the quality of service of a communication session according to claim 22, characterized in that it comprises, during the course of said communication session: a dynamic adaptation step of a QoS context by selecting a second class from among said set of service classes available for said communication session; and / or a step of transmitting a request for said second class of service to said at least one quality of service management entity; and / or - a step of receiving from said at least one quality of service management entity a confirmation of the allocation of said second class of service;

24. Mobile terminal capable of taking into account the quality of service of a communication session in a cellular network, between at least one quality of service management entity and at least one point of attachment, characterized in that it comprises, during the establishment of said communication session: means for receiving a set of classes of services available for said communication session from said at least one point of attachment; means for selecting from among said set of available service classes at least one first class of service; means for transmitting information representative of said first selected class of service to said at least one management entity; means for receiving information representative of a confirmation of the allocation of said first selected class of service from said at least one management entity.

25. Mobile terminal according to claim 24, characterized in that it comprises, during the course of said communication session: means for dynamically adapting a quality of service context by selecting a second class from said set classes of services available for said communication session; means for transmitting a request for a second class of service to said at least one quality of service management entity; means for receiving confirmation of the allocation of said second class of service from said at least one quality of service management entity;

26. Computer program product downloadable from a communication network and / or stored on a computer-readable medium and / or executable by a microprocessor, characterized in that it comprises program code instructions for the execution of the method control device according to at least one of claims 12 to 14 when executed on a computer.

27. Computer program product downloadable from a communication network and / or stored on a computer readable medium and / or executable by a microprocessor, characterized in that it comprises program code instructions for the execution of the steps the routing method according to at least one of claims 18 and 19, when executed on a computer.

28. Computer program product downloadable from a communication network and / or stored on a computer readable medium and / or executable by a microprocessor, characterized in that it comprises program code instructions for the execution of the steps method of taking into account the quality of service according to at least one of claims 22 and 23, when executed on a computer.