WO2008148422A1

WO2008148422A1 - Method for providing quality-of-service in a network

Info

Publication number: WO2008148422A1
Application number: PCT/EP2007/055513
Authority: WO
Inventors: David Mariblanca Nieves
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2007-06-05
Filing date: 2007-06-05
Publication date: 2008-12-11

Abstract

A method for setting quality-of-service mapping information in a network node is defined. The network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use the quality-of-service mapping information for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet. The method includes a receiving procedure for receiving, by the network node, from a terminal and through a signalling communication channel, quality-of-service mapping information associated with the terminal; and a storing procedure for storing, by the network node, the quality-of-service mapping information in association with an identifier identifying the terminal.

Description

Description [Title]

Method for providing quality-of-service in a network

[Technical Field]

The present invention relates to a method of setting quality-of-service mapping information in a network node, especially in a network node interfacing two communication networks .

[Background]

Information may be transmitted over a communication network, such as a computer network or a mobile communication network, in the form of a formatted block of information, known as a data packet. A data packet may for instance include a header, the payload and a trailer. A header may include information for identifying the data packet destination, the payload is the information to be carried out on the network in the data packet, and the trailer may mark the end of the data packet. Networks on which such data packets are switched or routed are called packet-switched networks. An example of data packet is an Internet Protocol (IP) packet.

The transfer of data packets over a network has led to the development of control mechanisms for ensuring a certain level or type of reliability, performance or integrity. For instance, the transfer delay of a packet over a network, the bit rate for a flow of data packets, or any other characteristics related to the transfer of the data packet over the network may constitute the target of such control mechanisms . The term quality-of-service refers to the collective effect of a set of requirements or policies implemented on a network by control mechanisms to ensure that goals relating to reliability, performance, integrity or other factors are met. The quality-of-service may be used to determine or express the degree of satisfaction of a user of a service, such as a service consisting in transferring data packets over a network.

The control mechanisms set up to implement a quality-of- service on a network are referred to in what follows as quality-of-service mechanisms. Quality-of-service mechanisms may be implemented on a network and may be applied to data packets and their transfer over the network with the aim of ensuring a target quality-of-service. The quality-of-service mechanisms may be implemented on or applied to different protocol layers, for instance in the Open Systems Interconnection Basic Reference Model (OSI model) or TCP/IP model. Depending on the protocol layer on which a quality-of-service mechanism is implemented, the quality-of-service mechanism may be implemented or enforced on some types of network nodes or network entities while not on others .

In some quality-of-service mechanisms, the type of data packets or some of their characteristics need to be identified or recognized by a network node for properly implementing the quality-of-service mechanism on the network. The identification of some information in the data packet or some information related to the data packet enables the application of different treatments or policies to different data packets. In other words, the handling of a data packet or group of data packets may be made dependent on the type or characteristics of the data packet or group of data packets. For example, data packets representing voice may form one category of data packets in a given network and the data packets representing email messages may form another category of data packets in the network. Thus, in this example, by identifying what kind of information the data packets contain or represent, different policies may be applied to the data packets representing voice compared to the data packets representing email messages.

In another example, data packets coming from a particular important subscriber may form one category of data packets in a given network and the data packets coming from a less important subscriber may form another category of data packets in the network. Thus, in this example, by identifying the origin of the data packets, different policies may be applied to the data packets coming from the important subscriber in comparison to the data packets coming from the less important subscriber.

In other words, the quality-of-service related treatment applied to data packets by network nodes may be different depending on the type of traffic, the content of the data packets, their origin, their destination or any other characteristics .

In some quality-of-service mechanisms, a quality-of- service, which is defined in particular here with respect to packet traffic as a piece of information identifying a category of quality-of-service to be provided to the traffic to which belongs a data packet, may be assigned to some of or each of the data packets transmitted on the network. As a result, the network nodes responsible for implementing the quality-of-service mechanisms are capable of identifying or recognizing the quality-of-service associated with data packets and how the quality-of-service mechanism should be applied to the data packets. Examples of quality-of-service mechanisms include:

Resource Reservation Protocol (RSVP) , described in Braden, R., Zhang, L., Berson, S., Herzog, S. and S. Jamin, "Resource Reservation protocol (RSVP) -- Version 1 Functional Specification", RFC 2205, September 1997".

Diffserv, described in Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z. and W. Weiss, "An Architecture for Differentiated Services", RFC 2475, December 1998, and Nichols, K., Blake, S., Baker, F. and D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers", RFC 2474, December 1998.

RSVP and Diffserv take action on Internet protocol (IP) packets. These two quality-of-service mechanisms are implemented by routers or firewalls.

Another example of quality-of-service mechanism is the mechanism provided by Universal Mobile Telecommunications System (UMTS) bearer classes and described in 3GPP TS 23.107: "Universal Mobile Telecommunications System (UMTS) ; Quality of Service (QoS) concept and architecture", V6.4.0, March 2006, where 3GPP means 3rd Generation Partnership Project and TS means Technical Specification. Bearer classes are defined, which each targets a specific type of data packet traffic.

As explained above, information may be transmitted over a communication network in the form of data packets. Two or more such communication networks may be connected together to enable the transfer of data packets from one point of a first communication network to another point in a second network. Two communication networks may be connected together by a network node, also called gateway node, interfacing the two networks .

Data packets may for example be transferred from a first point of a first communication network to a second point in a second communication network. In this example, the first point may be a computer, such as a server computer, in a first communication network being a computer network, and a second point may be a terminal, such as a mobile station terminal, in a second communication network being a wireless communication network.

Different quality-of-service mechanisms may be used on different communication networks which are connected together. For a data packet coming from a first communication network and which is to be transferred on a second communication network using a quality-of-service mechanism different from that of the first communication network, it is therefore desirable to provide a mechanism for translating a quality-of-service assigned to the data packet and conformable to the quality-of-service mechanism used on the first communication network to a quality-of- service conformable to the quality-of-service mechanism used on the second communication network.

The aim is to subject, whenever possible, a data packet traversing the two networks to similar policies on the two networks and to therefore provide quality-of-service consistency throughout the networks.

In order to so, a known method is to provide a mapping mechanism between the quality-of-service classes or categories conformable with the quality-of-service mechanism used on the first communication network and the quality-of-service classes or categories conformable with the quality-of-service mechanism used on the second communication network. A data packet arriving at the gateway node from the first communication network and assigned with a first quality-of-service conformable with the first communication network may therefore be assigned a second quality-of-service conformable with the second communication network and corresponding to the first quality-of-service according to the mapping, so that the data packet is properly handled, and to a certain extent consistently handled, by the second communication network.

No simple and flexible method exists for maintaining mapping information usable by the gateway node to perform such a quality-of-service assignment task.

It is therefore desirable to provide a simple and flexible method for maintaining mapping information to be used in a gateway node for assigning quality-of-service to a data packet arriving at the gateway node.

[Summary]

Such a method is provided by claim 1. Advantageous embodiments are described in the dependent claims.

One advantage of the present invention is the possibility for a network node to receive quality-of-service mapping information from a terminal, especially quality-of-service mapping information which is specific to a terminal or to a user of a terminal.

According to the present invention, a method for setting quality-of-service mapping information in a network node is provided. The network node is configured to interface a first communication network using a first quality-of- service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use the quality- of-service mapping information for assigning a quality-of- service to a data packet arriving at the network node depending on attributes associated with the data packet. The method includes a receiving procedure for receiving, by the network node, from a terminal and through a signalling communication channel, quality-of-service mapping information associated with the terminal; and a storing procedure for storing, by the network node, the quality-of- service mapping information in association with an identifier identifying the terminal.

The identifier identifying the terminal can be an identifier of the terminal itself, i.e. a terminal identifier, an identifier of a user operating the terminal, i.e. a user terminal, or any other identifier related to the terminal .

The operation consisting in assigning a quality-of-service to a data packet may include adding information associated to the quality-of-service to the data packet or more generally associating a quality-of-service to a data packet without necessarily adding information to the data packet or modifying the data packet in any way.

The method enables a terminal to efficiently send quality- of-service mapping information to the network node. A terminal can therefore properly and rapidly indicate to the network node how, at a particular moment and in accordance with the current needs or operation of the terminal, quality-of-service should be assigned to the data packets coming from or going to the terminal. The use of a signalling communication channel enables the terminal to inform the network node in a flexible and convenient manner . Upon reception of the quality-of-service mapping information associated with the terminal, the network node can therefore update the stored quality-of-service mapping information, which may for instance be a mapping table. The update operation enables to map quality-of-service classes or categories of the first communication network with quality-of-service classes or categories of the second communication network, in direct response to the terminal communicating quality-of-service mapping information in association with an identifier associated with the terminal. Furthermore, unknown or missing mapping information can be added to the stored quality-of-service mapping information on the network node interfacing the two networks and in charge of assigning quality-of-service to data packets.

In the invention, a terminal or an application running on the terminal can thus provide to the network node information associated with the terminal or associated with the data packets coming from or going to the terminal. By such an operation, the network node is made aware of information needed to properly and consistently assign quality-of-service to data packets coming from or going to the terminal. The information sent to the network node is specific to the terminal, thus enabling flexible and dynamic operation of the network node and the other constituents of the network. The invention neither requires a complex quality-of-service management system nor any complex overhaul of existing network management systems.

According to one embodiment, the method further includes a packet receiving procedure for receiving, by the network node, a data packet; an assigning procedure for assigning, by the network node, a quality-of-service to the data packet depending on attributes associated with the data packet, by using stored quality-of-service mapping information; and a packet transmitting procedure for transmitting, by the network node, the data packet.

This advantageously enables the efficient operation of the network node by making use of the stored quality-of-service mapping information when receiving data packets, so that the data packets can be properly and consistently handled by quality-of-service mechanisms.

Preferably, the storing procedure includes storing the quality-of-service mapping information in a table mapping quality-of-service categories in the first communication network with quality-of-service categories in the second communication network.

Storing the quality-of-service mapping information in the form of a table is a simple and efficient way to retain in memory, for use by the network node, the correspondence between the respective quality-of-service classes or categories used on the two communication networks, and to enable the network node to conveniently obtain the information required for the quality-of-service assignment.

According to a further embodiment, the first communication network is a mobile communication network and the signalling communication channel includes an Unstructured Supplementary Service Data (USSD) communication channel between the terminal and the network node.

In this embodiment, the terminal, after starting a new service using for instance a protocol with a non-predefined port, can initiate a Unstructured Supplementary Service Data (USSD) request to update the protocol ports in the stored quality-of-service mapping information accessible by the network node. The network node is thus made aware in a simple and fast manner of the unknown or missing information relating to the service initiated by the terminal and, subsequently, the network node can properly assign quality-of-service to the data packets.

The new service may for example be a Push-To-Talk conversation, and the protocol may for example be the Realtime Transport Protocol (RTP) , as defined in Schulzrinne, H., Casner, S., Frederick, R. and V. Jacobson, "RTP: A Transport Protocol for Real-time Applications", RFC 3550, July 2003.

Furthermore, according to the present invention, a network node is also provided. The network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use quality-of-service mapping information in the network node for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet. The network node includes a receiver unit for receiving from a terminal and through a signalling communication channel, quality-of-service mapping information associated with the terminal; and a storing unit for storing the quality-of-service mapping information in association with an identifier identifying the terminal .

Furthermore, according to the present invention, a method for sending, by a terminal, quality-of-service mapping information to be set in a network node is also provided. The network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use the quality- of-service mapping information for assigning a quality-of- service to a data packet arriving at the network node depending on attributes associated with the data packet. The method includes a sending procedure for sending, by the terminal, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal.

Furthermore, according to the present invention, a terminal configured for sending quality-of-service mapping information to be set in a network node is also provided. The network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use the quality- of-service mapping information for assigning a quality-of- service to a data packet arriving at the network node depending on attributes associated with the data packet. The terminal includes a sending unit for sending, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal.

Furthermore, according to the present invention, a method for sending, by a terminal, quality-of-service mapping information and setting it in a network node is also provided. The network node is configured to interface a first communication network using a first quality-of- service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use the quality- of-service mapping information for assigning a quality-of- service to a data packet arriving at the network node depending on attributes associated with the data packet. The method includes a sending procedure for sending, by the terminal, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal; a receiving procedure for receiving, by the network node, from a terminal and through a signalling communication channel, quality-of-service mapping information associated with the terminal; and a storing procedure for storing, by the network node, the quality-of-service mapping information in association with an identifier identifying the terminal.

Furthermore, according to the present invention, a system comprising a terminal and a network node is also provided. The terminal is configured for sending quality-of-service mapping information to be set in the network node. The network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use quality-of- service mapping information in the network node for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet. The terminal includes a sending unit for sending, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal. The network node includes a receiver unit for receiving from the terminal and through a signalling communication channel, quality-of- service mapping information associated with the terminal; and a storing unit for storing the quality-of-service mapping information in association with an identifier identifying the terminal.

[Brief description of the drawings]

Embodiments of the present invention shall now be described, in conjunction with the appended figures, in which: Fig. 1 shows a schematic representation of a network configuration according to one embodiment of the invention;

Fig. 2 shows a flow chart illustrating the operation of a method according to one embodiment of the invention;

Fig. 3 shows a flow chart illustrating the operation of a method according to another embodiment of the invention;

Fig. 4 shows an exemplary table for storing the quality-of-service mapping information according to one embodiment of the invention;

Fig. 5 shows another exemplary table for storing the quality-of-service mapping information according to one embodiment of the invention;

Fig. 6A shows a schematic representation of a terminal according to one embodiment of the invention;

Fig. 6B shows a schematic representation of a network node according to one embodiment of the invention;

Fig. 6C shows a schematic representation of a network node according to another embodiment of the invention;

Fig. 7 shows an exemplary embodiment of a method according to the invention;

Fig. 8 shows a schematic representation of the state of a mapping table contained in or accessed by a network node in the example of Fig. 7;

Fig. 9 shows the state of a mapping table of Fig. 8, after an update according to one embodiment of the invention;

Fig. 10 shows the mapping table of Fig. 9 after PDP context change according to one embodiment of the invention; and

Fig. HA and HB illustrate a PDP context modification procedure used in a method according to one embodiment of the invention. [Detailed description]

The present invention shall now be described in conjunction with specific embodiments. It may be noted that these specific embodiments serve to provide the skilled person with a better understanding, but are not intended to in any way restrict the scope of the invention, which is defined by the appended claims.

Figure 1 schematically illustrates a network configuration according to an embodiment of the invention.

A first communication network 4 and a second communication network 6 use different quality-of-service mechanisms. A network node 2, or gateway node (labelled by "GW" in the Figure) , interfaces the first communication network 4 and the second communication network 6. The verb "to interface" means that the network node 2 is at least configured and capable to receive a data packet from at least one of the first communication network 4 and the second communication network 6 and configured and capable to send a data packet on at least the other one of the first communication network 4 and the second communication network 6. The network node 2 is said to be a unidirectional interfacing node if it is configured and capable to receive a data packet from at least one of the first communication network 4 and the second communication network 6 but not from the other one. In contrast, the network node 2 is said to be a bidirectional interfacing node if it is configured and capable to receive a data packet from both the first communication network 4 and the second communication network 6 for transmission to the other communication network.

When the network node 2 receives a data packet from one of the first communication network 4 and the second communication network 6, it processes it and transmits it on the other communication network. Processing the data packet by the network node 2 may include assigning, by the network node 2, a quality-of-service to the received data packet depending on attributes associated with the data packet. The processing of the data packet by the network 2 will be described later in more details.

A terminal 8, terminal device or terminal node (labelled by "UE" in the Figure, without however implying any limitation regarding the type of terminal and the protocols used on the network) , for instance a user equipment or mobile station, is connected to the first communication network 4, for instance a General Packet Radio Service (GPRS) network or a Universal Mobile Telecommunications System (UMTS) network. The terminal 8 is configured and capable to receive data packets from the first communication network 4, or to send data packets on the first communication network 4, or to both receive data packets from and send data packets on the first communication network 4.

The transmission of a data packet on the first communication network 4 from the terminal 8 to the network node 2 or from the network node 2 to the terminal 8 is performed on a data communication channel 14. The data communication channel 14 may be bidirectional, i.e. for transferring a data packet on the first communication network 4 both from the terminal 8 to the network node 2 or from the network node 2 to the terminal 8, or unidirectional for transferring data packets on the first communication network 4 in one direction only. In the case of a unidirectional data communication channel 14, a second unidirectional data communication channel may be provided for transferring data packets on the first communication network 4 in the other direction (not illustrated) .

A data communication channel is a route or channel on a network for transferring a data packet. The terminal 8 is additionally configured and capable to communicate on a signalling communication channel 12, different from the data communication channel 14, with the network node 2 for transmitting quality-of-service mapping information associated with the terminal 8. In one embodiment, the terminal 8 is configured and capable to initiate a signalling communication channel 12 with the network node 2.

A signalling communication channel is a route or channel on a network for transferring messages relating to the connection between a terminal and a network, e.g. between the terminal 8 and some other component on the network 4, such as the network node 2. In one embodiment, the signalling communication channel 12 is a route or channel on a network exclusively suitable for transferring messages relating to the connection between a terminal and a network or relating to the maintenance of the system, e.g. between the terminal 8 and some other component on the network 4, such as the network node 2.

A server 10 or server node, for instance a web server or web application server (labelled by "S" in the Figure), is connected to the second communication network 6, for instance an Internet Protocol (IP) network, either public or private. The server 10 is configured and capable to receive data packets from the second communication network 6, or to send data packets on the second communication network 6, or to both receive data packets from and send data packets on the second communication network 6.

The transmission of a data packet on the second communication network 6 from the server 10 to the network node 2 or from the network node 2 to the server 10 is performed on a data communication channel 16. Like the above-mentioned data communication channel 14, the data communication channel 16 may be bidirectional, i.e. for transferring a data packet on the second communication network 6 both from the server 10 to the network node 2 or from the network node 2 to the server 10, or unidirectional for transferring data packets on the second communication network 6 in one direction only. In the case of a unidirectional data communication channel 16, a second unidirectional data communication channel may be provided for transferring data packets on the second communication network 6 in the other direction (not illustrated) .

The network node 2 according to the embodiment illustrated in Figure 1 is a network node configured to perform the network node related steps of the above-described method. In particular, as illustrated in Figure 6B, it includes a receiver unit 24 for performing the receiving procedure and a storing unit 26 for performing the storing procedure.

The terminal 8 according to the embodiment illustrated in Figure 1 is a terminal configured to perform the terminal related steps of the above-described method. In particular, as illustrated in Figure 6A, it includes a sending unit 22 for performing the sending procedure for sending the quality-of-service information associated with the terminal 8 through the signalling communication channel 12.

The sending procedure for sending, by the terminal 8, to the network node 2 and through a signalling communication channel 12, quality-of-service mapping information associated with the terminal 8, may be performed by a sending unit 22 of the terminal 8, and may be automatically initiated by an application, such as a service application, executing on the terminal 8.

Figure 2 schematically illustrates the operation of a method according to an embodiment of the invention. In operation, the terminal 8 sends in step S202 quality-of- service mapping information associated with the terminal 8 to the network node 2 through a signalling communication channel 12. The network node 2 then receives in step S204 the quality-of-service mapping information and, in step S206, the network node 2 stores it in association with an identifier identifying the terminal 8. The stored quality- of-service mapping information enables later assignment of quality-of-service information to data packets and processing of the data packets according to policies and rules implemented by quality-of-service mechanisms.

The identifier identifying the terminal 8 can be an identifier of the terminal 8 itself, i.e. a terminal identifier, an identifier of a user operating the terminal 8, i.e. a user terminal, or any other identifier related to the terminal 8. An example of such identifier is the key identifying a mobile phone service subscriber, as stored in a Subscriber Identity Module (SIM) card number, in a Universal Integrated Circuit Card (UICC) or in a Removable User Identity Module (R-UIM) . The identifier may also be for instance any identifier identifying a user subscribing to mobile phone service, where the identifier is stored for instance on a chip card which is removable from a mobile phone or handset generally allowing the user to change mobile phone or handset easily by simply removing the card from a mobile phone or handset and inserting it into another mobile phone or handset.

Figure 3 schematically illustrates an operation of a method according to another embodiment of the invention.

The following steps S308, S310, S312 may be performed after the network node 2 has stored, in step S206 (Figure 2), the received quality-of-service mapping information in association with an identifier identifying the terminal 8. In step S308, the packet receiving procedure is carried out. The packet receiving procedure includes a procedure wherein the network node 2 receives a data packet from one of the first communication network 4 and the second communication network 6.

In step S310, the assigning procedure is then carried out. The assigning procedure includes a procedure wherein the network node 2 assigns in step S310 a quality-of-service to the data packet depending on attributes associated with the data packet by using stored quality-of-service mapping information. In other words, the network node 2 obtains or receives attributes associated with the data packet and uses the stored quality-of-service mapping information depending on these attributes to assign a quality-of- service to the data packet.

The assigning procedure for assigning a quality-of-service to the data packet may however result in not assigning any quality-of-service to the data packet if, for instance, depending on attributes associated with the data packet and by using stored quality-of-service mapping information, a determination is made that no quality-of-service corresponds, in the stored quality-of-service mapping information, to the attributes associated with the data packet. The assigning procedure for assigning a quality-of- service to the data packet may also result in assigning a default quality-of-service to the data packet if, for instance, depending on attributes associated with the data packet and by using stored quality-of-service mapping information, a determination is made that a default quality-of-service corresponds to the attributes associated with the data packet for whatever reason related to the stored quality-of-service mapping information or related to the method of operation of the network node 2. After the assigning procedure in step S310, the packet transmitting procedure is carried out. The packet transmitting procedure includes a procedure wherein the data packet is transmitted, in step S312, on the other one of the first communication network 4 and the second communication network 6. If a quality-of-service conformable with the communication network on which the data packet is transmitted has been assigned to the data packet, the data packet can therefore be handled by appropriate quality-of-service mechanisms which are proper to said communication network. This helps ensuring consistent handling of the data packets regarding quality- of-service .

As illustrated in Figure 6C, showing a schematic representation of the network node 2, the packet receiving procedure may be performed by a packet receiving unit 28, the assigning procedure for assigning a quality-of-service to the data packet may be performed by an assigning unit 30, and the packet sending procedure may be performed by a packet sending unit 30. The packet receiving unit 28, the packet receiving unit 28 and the assigning unit 30, like the receiving unit 24 and the storing unit 26, may be part of the network node 2, or may be distributed on several distributed sub-components or sub-nodes of the network node 2 in such a manner that the method according to the invention may be carried out by the network node 2.

In one embodiment, as illustrated in Figure 4, the storing procedure in step S206 includes storing the quality-of- service mapping information in a table 20 mapping quality- of-service categories 22 in the first communication network 4 with quality-of-service categories 24 in the second communication network 6, in association with identifiers 26 identifying the terminals. In the example of Figure 4, two identifiers "identifier 1" and "identifier 2" are illustrated, and each row defines the mapping at a given moment of one category conformable with the first communication network 4 with one category conformable with the second communication network 6.

In the example of Figure 4, the mapping is illustrated as being partially different for the two identifiers. This needs not necessarily be the case. At one given moment, the mapping may be the same of two or more identifiers.

The mapping at a given moment does not necessarily cover all quality-of-service categories, as illustrated in the example of Figure 4. In relation to the identifier "identifier 1", there is no category conformable with the second communication network 6 which is mapped to the quality-of-service category "category 4". In relation to the identifier "identifier 2", there is no category conformable with the second communication network 6 which is mapped to the quality-of-service category "category 2". In this respect, the mapping information is said to be missing or unknown.

In this example, if it is determined at the network node 2 that an incoming data packet is associated with the identifier "identifier 1" and has attributes associated with the quality-of-service category "category 4" or if it is determined that an incoming data packet is associated with the identifier "identifier 2" and has attributes associated with the quality-of-service category "category 2", the network node 2 may in operation assign a default quality-of-service to the data packet or may assign no quality-of-service at all. This may also apply to a flow of data packets.

In one embodiment, the storing procedure in step S206 may include replacing or updating a quality-of-service mapping information entry existing in the stored quality-of-service mapping information on the network node 2, for instance in the mapping table illustrated in Figure 4, by the received quality-of-service mapping information. Alternatively, it may include setting a new quality-of-service mapping information entry, for instance a new row in the table illustrated in Figure 4, based on the received quality-of- service mapping information.

Although not illustrated, in the case of a bidirectional interfacing network node 2, the mapping may be different for data packets coming from the first communication network 4 and going to the second communication network 6 and for data packets coming from the second communication network 6 and going to the first communication network 4. A common table or two tables, one per direction of packet transfer, may be provided in the method according to such embodiment .

The mapping may be more selective, including columns for containing information about other attributes of the traffic, such as the destination port number (which may for instance be a Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) protocol port) , the PDP context identifier in a GPRS system, a name of an access point in a GPRS system or a protocol identifier. The Packet Data Protocol (PDP) context is a data structure defining the communication session between the terminal 8 and the network node 2 in a 3GPP network. In the exemplary 3GPP network, the PDP context realizes the connectivity between the user equipment 8 and a gateway node 2. When a PDP context is set up, an access point having an access point name (APN) may be selected. The access point identifies the communication network, for instance an IP network, accessible from the terminal 8 through the interfacing network node 2. Figure 5 illustrates an example of such a more selective mapping table. Even more selective mapping tables may be provided, without limitations.

In another embodiment, the first communication network 4 is a mobile communication network and the signalling communication channel 12 includes an Unstructured Supplementary Service Data (USSD) communication channel between the terminal 8 and the network node 2. Unstructured Supplementary Service Data (USSD) operations are described for instance in 3GPP TS 22.090: "Digital cellular telecommunications system (Phase 2+) ; Universal Mobile Telecommunications System (UMTS) ; Unstructured Supplementary Service Data (USSD); Stage 1", version 7.0.0 Release 7, June 2006.

In another embodiment, the signalling communication channel 12 is or includes a signalling communication channel 12 used to modify a PDP context. The modification of a PDP Context is better understood with reference to Figure HA and HB (which correspond to Figures 72a and 72b in 3GPP TS 23.060 version 7.4.0 Release 7 (2007-03)). The signalling messages used for modifying a PDP context are used in this embodiment. To this end, an extension container may be inserted in the message. The network node 2, or GGSN 52, would interpret the extension container in a proper manner to enable the recognition of the quality-of-service mapping information. In this embodiment, and with additional reference to the example of Figure 7 (described later) , since the SGSN 60 is terminating and initiating the messages, the SGSN 60 behaviour may need to be modified so that, when the SGSN 60 detects the extension container, the SGSN 60 initiates the Update PDP Context Request towards the GGSN 52, with no further actions (like Radio Access Bearer Modification, shown in the Figure). In another embodiment, the first quality-of-service mechanism is based on UMTS bearer classes. The term "bearer" refers to an edge-to-edge association between a terminal 8 and a network node 2.

In another embodiment, the second communication network 6 is an Internet Protocol (IP) network including differentiated service compliant nodes or services. The differentiated service compliant nodes or services may be compliant with Diffserv, as defined by RFC 2475 and RFC 2474 (detailed references mentioned above) .

In another embodiment, the first communication network 4 is a mobile communication network and the quality-of-service mapping information associated with the terminal 8 includes at least one of the following information: a destination port number, a protocol identifier, a PDP context identifier in a GPRS system, a name of an access point in a GPRS system and a Diffserv class.

In another embodiment, a computer program is provided such that the above-described network node related steps are caused to be performed by a network node 2 when the computer program is executed on the network node 2. In yet another embodiment, a computer program is provided such that the above-described terminal related steps are caused to be performed by a terminal 8 when the computer program is executed on the terminal 8. The computer programs may be stored or comprised in computer program products or mediums, such as for instance a magnetic disk, an optical disk, a read-only memory (ROM) or Random access memory

(RAM) , and may for instance be executed on the network node 2 or terminal 8 in any type of central processing unit

(CPU) .

An exemplary embodiment of the method and system according to the invention is illustrated in Figure 7. The network configuration of this exemplary embodiment may be described in the following manner. A General Packet Radio Services (GPRS) Core Network 50 comprises two GPRS support nodes which support the use of GPRS in the GSM core network. The first GPRS support node is a Serving GPRS Support Node (SGSN) 60, which mediates access to network resources on behalf of the terminals 8 and may implement portions of the quality-of-service mechanism. The second GPRS support node is a Gateway GPRS support Node (GGSN) 52, which acts as the network node 2 or gateway node interfacing a first communication network 4, in this exemplary embodiment a GSM compliant mobile communication network comprising the GPRS Core Network 50 and the radio access network (RAN) 54 (including the base station and optional supporting radio-related facilities) , with a second communication network 6, in this exemplary embodiment an Internet protocol (IP) network 56.

A Home Location Register (HLR) 64 is also provided. The Home Location Register (HLR) 64 is a database comprising information relating to the terminal subscribers authorized to use the mobile communication network. A Mobile Switching Center (MSC) and a Visitor Location Register (VLR) , MSC/VLR 62, are also provided.

A terminal 58, which is a user equipment (UE) , is connected to a radio access network 54, which together with the GPRS Core Network 50, forms the first communication network 4. A router 68 routes data packets from the Gateway GPRS support Node (GGSN) 52 to an Internet Protocol (IP) network 56, to which a web server 10 is connected.

In this exemplary embodiment, the quality-of-service mechanism used on the first communication network 54 is based on the use of UMTS Bearer classes. In other words, the UMTS Bearer classes constitute the basis of the quality-of-service mechanism used from the terminal (UE) 58 to the Gateway GPRS support Node (GGSN) 52. From the Gateway GPRS support Node (GGSN) 52 to the web server 10, the quality-of- service mechanism is based on another protocol, as described later.

Four bearer classes are defined, each targeting a specific type of user traffic. This is however one exemplary embodiment only and more or less bearer classes may be defined. A bearer class may be a combination of quality-of- service attributes and optional associated value ranges.

The four exemplary UMTS bearer classes (UMTS bearer classes in 3GPP release 1999) and their characteristics are:

"Conversational" with the characteristics: "minimum fixed delay, no buffering, symmetric traffic, guaranteed bit rate" and intended to real-time traffic.

"Streaming" with the characteristics: "minimum variable delay, buffering allowed, asymmetric" and intended to near real-time traffic.

"Interactive" with the characteristics: "moderate variable delay, no delay guarantee, buffering allowed, asymmetric traffic, no guaranteed bit rate" and intended to non real-time traffic.

"Background" with the characteristics: "big variable delay, no delay guarantee, buffering allowed, asymmetric traffic, no guaranteed bit rate" and intended to data synchronization .

The main difference between the Bearer classes is the delay characteristic target. The "Conversational" quality-of- service class is intended for traffic which is very delay sensitive while the "Background" quality-of-service class is the most delay insensitive traffic class. The "Conversational" and "Streaming" classes are used to carry real-time or near real-time traffic flows. The main difference between the bearer classes in this exemplary embodiment is the traffic sensitivity to delay and delay variation. Other type of differences may be provided. Conversational real-time services, such as video telephony, are the most delay sensitive applications and these should be carried in association with the "Conversational" quality-of-service class on the mobile communication network 50, 54.

The "Interactive" and "Background" quality-of-service classes are used by Internet applications like HTTP messages, email messages, telnet messages, FTP messages and news messages. The traffic of data packets for these applications present less constraining delay requirements than the traffic in the "Conversational" or "Streaming" quality-of-service classes. Both "Interactive" and "Background" classes may provide better error rates than the other classes by means of channel coding and retransmission .

In this exemplary embodiment, the UMTS bearer classes are negotiated during PDP context establishment (a process which is described below) . The PDP context is therefore associated with a quality-of-service, such as the bearer class "Interactive" or "Background" and so on, and all data traffic inside the PDP context is treated according to the bearer class associated with the PDP context. The bearer class associated with a PDP context can be negotiated anew at any time by performing an update of the PDP context.

Still in this exemplary embodiment, the second quality-of- service mechanism used on the second communication network 56 is based on the Diffserv protocol. The Diffserv protocol defines quality-of-service categories or classes, called per-hop behaviour (PHB) . Exemplary Diffserv quality-of- service classes are herewith described. The per-hop behaviour (PHB) "NC", defined in RFC 2474, corresponds to network control traffic. The per-hop behaviour (PHB) "EF" ("EF" stands for "expedited forwarding") , defined in RFC 3246, corresponds to high priority traffic with guaranteed minimum bit rate and low latency requirements. The quality- of-service categories "AF4[1..3]", "AF3[1..3]", "AF2[1..3]" and "AFl[I..3]" ("AF" stands for "assured forwarding"), defined in RFC 2597, constitute a group of per-hop behaviours (PHB) with forwarding assurance, providing differentiated precedence and loss probability. The per-hop behaviour (PHB) "BE", defined in RFC 2474, corresponds to a best effort traffic characteristic.

It is assumed that all traffic, i.e. the traffic of data packets, is routed from the terminal 58 to the Gateway GPRS support Node (GGSN) 52 through one PDP context.

The Gateway GPRS support Node (GGSN) 52 comprises or has access to a mapping table as shown in Figure 8.

As illustrated in Figure 8, the port number is present for some protocols in the table. This is the case for Hypertext Transfer Protocol (HTTP) (with "Protocol number" value equal to 1) and Session Initiation Protocol (SIP) (with "Protocol number" value equal to 4) . In contrast, the port number is missing or unknown for other protocols. This is the case for Real-time Transport Protocol (RTP) (with "Protocol number" value equal to 2) and File Transfer Protocol (FTP) (with "Protocol number" value equal to 3). The Gateway GPRS Support Node (GGSN) 52 may not be capable to carry out a mapping and an assignment of quality-of- service for data packets which use the latter two protocols. In addition, as illustrated, the PDP contexts with respect to which the quality-of-service (QoS) has to be assigned is also unknown to the Gateway GPRS Support Node (GGSN) 52. This is the case for all protocol numbers.

Initially, the terminal (UE) 58 performs a normal Packet Data Protocol (PDP) context activation. This means that a GPRS Tunnelling Protocol (GTP) tunnel 66 is set up between the Serving GPRS Support Node (SGSN) 60 and the Gateway GPRS Support Node (GGSN) 52. A connection is therefore set up from the terminal (UE) 58 to the Serving GPRS Support Node (SGSN) 60 and then to the Gateway GPRS Support Node (GGSN) 52.

The Serving GPRS Support Node (SGSN) 60 then detects that the PDP context has been activated and sends a modified update GPRS Location MAP operation to the Home Location Register (HLR) 64.

The modified Update GPRS Location operation includes the GGSN address where the terminal (UE) 58 is terminating the PDP context. The Home Location Register (HLR) 64 updates the External Node Address Profile of the associated user, in order to reflect the GGSN address as External Node address .

Once the terminal (UE) 58 initiates a new service, for example Push to Talk, which uses a protocol with a non- predefined port (in the example, RTP) , the terminal 58 (UE) initiates a USSD request to the Home Location Register (HLR) 64. The service code in the USSD request indicates the purpose of the request, i.e. to update the protocol ports and PDP context IDs or Access Point Names (APNs) in the Gateway GPRS support Node (GGSN) 52. The Home Location Register (HLR) 64, using the External Node Address Profile where the GGSN address is stored, forwards the request to the Gateway GPRS support Node (GGSN) 52. The Gateway GPRS support Node (GGSN) 52 then knows which ports it has to use to perform the Diffserv quality-of-service class mapping (in the example, Real-time Transport Protocol (RTP) will most likely be assigned Diffserv class "EF") , and for which PDP context or access points the mapping has to be made.

For example, if the other peer, i.e. the server 10, communicates to the terminal (UE) 58 that the RTP port to use is "1500", the terminal (UE) 58 therefore sends an exemplary USSD string like "**205**2*1500*10#", wherein:

"205" indicates the service to use, for instance "protocol assignment", which is one exemplary type of transfer of quality-of-service mapping information. It enables the Home Location Register (HLR) 64 to know the role and purpose of the USSD string, i.e. that the USSD string should be forward to the Gateway GPRS support Node (GGSN) 52;

"2" indicates the protocol number, in this case Real-time Transport Protocol (RTP) . This is a protocol numbering system known by the terminal (UE) 58 and the GPRS core network 50 (therefore it does not necessarily need to be standardized, but it may be standardized) ;

"1500" is the destination port number assigned to Real-time Transport Protocol (RTP) ; and

"10" is the PDP context ID being used by the terminal (UE) 58 for this Real-time Transport Protocol (RTP) traffic.

Once the Gateway GPRS support Node (GGSN) 52 receives the USSD string, it stores the quality-of-service mapping information. The updated state of the mapping table is illustrated in Figure 9. For other protocols than RTP, the Gateway GPRS support Node (GGSN) 52 does not know at this stage with which PDP context they are associated, as illustrated by the three question marks in the PDP Context ID column of the table. The Gateway GPRS support Node (GGSN) 52 takes any one of the following decisions to handle this type of traffic:

Assigning a quality-of-service for the data packets associated with the protocol for which the Diffserv mapping is known, whatever PDP context they belong to (in this case the Gateway GPRS support Node (GGSN) 52 would apply mapping for HTTP and SIP, regardless the PDP context being used for them) .

Not applying any mapping at all, until an explicit indication is received from the terminal (UE) 58 with the PDP context ID of each protocol.

The Gateway GPRS support Node (GGSN) 52 may be configured beforehand to behave in any one of these above-mentioned manners .

Once the terminal (UE) 58 starts streaming IP packets using RTP, the Gateway GPRS Support Node (GGSN) 52 applies Diffserv mapping and the router 68 (or any other network node, for example a firewall) applies the corresponding policies and priorities, i.e. the corresponding quality-of- service mechanisms.

The Gateway GPRS Support Node (GGSN) 52 may apply a different quality-of-service mapping for a certain IP flow, on a PDP context basis or on an Access Point (APN) basis. In this embodiment, such mode of operation is enabled by allowing the terminal (UE) 8 to send quality-of-service mapping information, such as for instance the protocol ports, the PDP context ID or the APN used, to the network node 2 at any time and swiftly after a service is initiated in the terminal (UE) 8.

Initially, the Home Location Register (HLR) 64 does not know the GGSN address and needs to be aware of it. In one embodiment, the Update GPRS Location MAP operation is configured so as to send the GGSN address to the Home Location Register (HLR) 64. The GGSN address is stored in the Home Location Register (HLR) 64 as External Node address. The External Node addresses in the Home Location Register (HLR) 64 are stored as part of the External Node Address Profile. These profiles are assigned per identifier, i.e. per user or per MSISDN address range, wherein MSISDN stands for Mobile Station International Subscriber Directory Number and wherein a SIM card may have several MSISDNs . The External Node Address Profiles are checked when a USSD string is received, using the service code in the USSD string and the MSISDN to find the proper profile .

In one embodiment, in case of downlink traffic (i.e. from the Gateway GPRS Support Node (GGSN) 52 to the terminal (UE) 8), and when more than one PDP context are used, the PDP context where the traffic has to be injected towards the terminal (UE) 8 may be selected.

At any time, if the terminal (UE) 58 initiates another service using another protocol, the procedure starts again by initiating a USSD request and so on. This procedure does not require any user awareness, it may be performed automatically by an application executing on the terminal (UE) 58.

If the terminal (UE) 58 is disconnected from the GPRS network 50, 54 and if afterwards the terminal (UE) 58 is connected to the GPRS network 50, 54 again, the Update GPRS Location procedure is triggered and the GGSN address is updated in the External Node Address Profile in the Home Location Register (HLR) 64.

Another exemplary embodiment of the method according to the invention is herewith explained wherein a PDP context change is performed. In this example, a Diffserv quality- of-service mapping exists at a given moment and the PDP context is thereafter changed. The initial state of the mapping table may be the above-described one, illustrated in Figure 9.

The Gateway GPRS Support Node (GGSN) 52, as a result of the previous operations, is assumed to be configured with a table as illustrated in Figure 9.

The terminal (UE) 58 initiates a change of PDP context characteristics for Real-time Transport Protocol (RTP), and creates a new PDP context through which the Real-time Transport Protocol (RTP) flow is to be routed. The new PDP context ID is assumed "30" in the exemplary embodiment.

A different Diffserv mapping for Real-time Transport Protocol (RTP) flows is initiated from the terminal (UE) 58, in the new PDP context. As a result, the terminal (UE) 58 informs the Gateway GPRS Support Node (GGSN) 52 that the new PDP context with PDP context ID equal to "30", for Real-time Transport Protocol (RTP) traffic, shall have the Diffserv class "BE" (for example) . The terminal (UE) 58 performs this operation in a similar way as explained above by initiating a USSD request and so on. As a result, the state of the mapping table in the Gateway GPRS Support Node (GGSN) 52 is therefore the one illustrated in Figure 10.

Once the terminal (UE) 58 starts streaming IP packets using RTP, the Gateway GPRS Support Node (GGSN) 52 applies Diffserv mapping for the new PDP Context, with PDP context ID equal to "30", and the router 68 (or any other network node, for example a firewall) applies the corresponding policies and priorities, i.e. the corresponding quality-of- service mechanisms. The reason for this quality-of-service downgrade from Diffserv quality-of-service class "EF" to Diffserv quality-of-service class "BE", might for instance be the start of a video download service with poor quality which neither requires high bandwidth nor low jitter.

The Gateway GPRS Support Node (GGSN) 52 maps UMTS bearer classes to Diffserv classes and is made aware of the protocol ports of the data packets traversing it. The corresponding Diffserv mapping is applied per PDP context. The Gateway GPRS Support Node (GGSN) 52 is not forced to apply a default mapping which, in most of the cases, would not correspond to the type of protocol.

The introduction of a Gateway GPRS Support Node (GGSN) 52 which may be aware of the protocol allows supporting new protocols with no additional implementation costs. When an application with a new protocol is deployed on the terminal (UE) 58, the terminal (UE) 58 sends the protocol number and port number to the Gateway GPRS Support Node (GGSN) 52, which is thereafter configured to assign a Diffserv quality-of-service class to the data packets in correspondence with the protocol of said packets.

Different Diffserv quality-of-service classes can be assigned to IP data packets and the purchase of complex and costly solutions is not required. Furthermore, the ability to extend the system to new protocols is flexible, since it relies on a simple signalling communication between a terminal (UE) 8 and a Gateway GPRS Support Node (GGSN) 52. This enables network operators to offer a wide range of services to users, such as IP-based services (for instance Voice over Internet Protocol telephony, i.e. VoIP, mobile television services, and so on) , in a simple and cost efficient manner. In the above-described exemplary embodiment, any traffic being routed through any node, regardless of whether it implements the Rx interface, can be properly assigned with a Diffserv quality-of-service class, since the communication from the terminal (UE) 58 to the network uses a simple signalling communication channel 4, such as a USSD-based channel.

It should be understood that the methods and systems illustrated in the drawings are only examples, and that e.g. the components may also be arranged differently. Also, more than one Gateway GPRS Support Node (GGSN) 52 may be provided, and more than two networks may be arranged to be connected.

Although the present invention has been described on the basis of detailed examples, the detailed examples only serve to provide the skilled person with a better understanding, and are not intended to limit the scope of the invention. The scope of the invention is much rather defined by the appended claims.

Claims

1. Method for setting quality-of-service mapping information in a network node, wherein the network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of- service mechanism differing from the first quality-of- service mechanism, and to use the quality-of-service mapping information for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet; the method including a receiving procedure for receiving, by the network node, from a terminal and through a signalling communication channel, quality-of-service mapping information associated with the terminal; and a storing procedure for storing, by the network node, the quality-of-service mapping information in association with an identifier identifying the terminal .

2. Method of claim 1, further including a packet receiving procedure for receiving, by the network node, a data packet; an assigning procedure for assigning, by the network node, a quality-of-service to the data packet depending on attributes associated with the data packet, by using stored quality-of-service mapping information; and a packet transmitting procedure for transmitting, by the network node, the data packet.

3. Method of claim 1 or 2, wherein the storing procedure includes storing the quality-of-service mapping information in a table mapping quality-of-service categories in the first communication network with quality-of-service categories in the second communication network.

4. Method according to any one of the preceding claims, wherein the first communication network is a mobile communication network and the signalling communication channel includes an Unstructured Supplementary Service Data (USSD) communication channel between the terminal and the network node.

5. Method of claim 4, wherein the first quality-of- service mechanism is based on UMTS bearer classes.

6. Method according to any one of the preceding claims, wherein the second communication network is an IP network including differentiated service compliant nodes or devices.

7. Method according to any one of the preceding claims, wherein the storing procedure includes replacing, by the network node, existing quality-of-service mapping information with new quality-of-service mapping information .

8. Method according to any one of the preceding claims, wherein the first communication network is a mobile communication network and the quality-of-service mapping information associated with the terminal includes at least one of the following information: a destination port number, a protocol identifier, a PDP context identifier in a GPRS system, a name of an access point in a GPRS system and a Diffserv class .

9. Network node configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of-service mechanism differing from the first quality-of-service mechanism, and to use quality-of-service mapping information in the network node for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet; the network node including a receiver unit for receiving from a terminal and through a signalling communication channel, quality- of-service mapping information associated with the terminal; and a storing unit for storing the quality-of-service mapping information in association with an identifier identifying the terminal.

10. Network node of claim 9, further including a packet receiver unit for receiving a data packet; an assigning unit for assigning a quality-of- service to the data packet depending on attributes associated with the data packet, by using stored quality-of-service mapping information; and a packet transmitting procedure for transmitting the data packet.

11. Network node of claim 9 or 10, wherein the storing unit is configured for storing the quality-of-service mapping information in a table mapping quality-of- service categories in the first communication network with quality-of-service categories in the second communication network.

12. Network node according to any one of claims 9 to 11, wherein the first communication network is a mobile communication network and the signalling communication channel includes an Unstructured Supplementary Service Data (USSD) communication channel between the terminal and the network node.

13. Network node of claim 12, wherein the first quality- of-service mechanism is based on UMTS bearer classes.

14. Network node according to any one of claims 9 to 13, wherein the second communication network is an IP network including differentiated service compliant nodes or devices.

15. Network node according to any one of claims 9 to 14, wherein the storing unit is further configured to replace existing quality-of-service mapping information with new quality-of-service mapping information .

16. Network node according to any one of the claims 9 to 15, wherein the first communication network is a mobile communication network and the quality-of- service mapping information associated with the terminal includes at least one of the following information: a destination port number, a protocol identifier, a PDP context identifier in a GPRS system, a name of an access point in a GPRS system and a Diffserv class.

17. Method for sending, by a terminal, quality-of-service mapping information to be set in a network node, wherein the network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of- service mechanism differing from the first quality-of- service mechanism, and to use the quality-of-service mapping information for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet; the method including a sending procedure for sending, by the terminal, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal.

18. Method of claim 17, wherein the first communication network is a mobile communication network and the signalling communication channel includes an Unstructured Supplementary Service Data (USSD) communication channel between the terminal and the network node.

19. Method of claim 18, wherein the first quality-of- service mechanism is based on UMTS bearer classes.

20. Method according to any one of claims 17 to 19, wherein the second communication network is an IP network including differentiated service compliant nodes or devices.

21. Method according to any one of claims 17 to 20, wherein the sending procedure includes sending quality-of-service mapping information to replace existing quality-of-service mapping information stored in the network node.

22. Method according to any one of claims 17 to 21, wherein the first communication network is a mobile communication network and the quality-of-service mapping information associated with the terminal includes at least one of the following information: a destination port number, a protocol identifier, a PDP context identifier in a GPRS system, a name of an access point in a GPRS system and a Diffserv class.

23. Method according to any one of claims 17 to 22, wherein the sending procedure is automatically initiated by a service application executing on the terminal .

24. Terminal configured for sending quality-of-service mapping information to be set in a network node, wherein the network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of- service mechanism differing from the first quality-of- service mechanism, and to use the quality-of-service mapping information for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet; the terminal including a sending unit for sending, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal .

25. Terminal of claim 24, wherein the first communication network is a mobile communication network and the signalling communication channel includes an Unstructured Supplementary Service Data (USSD) communication channel between the terminal and the network node.

26. Terminal of claim 25, wherein the first quality-of- service mechanism is based on UMTS bearer classes.

27. Terminal according to any one of claims 24 to 26, wherein the second communication network is an IP network including differentiated service compliant nodes or devices.

28. Terminal according to any one of claims 24 to 27, wherein the sending unit is configured for sending quality-of-service mapping information to replace existing quality-of-service mapping information stored in the network node.

29. Terminal according to any one of claims 24 to 28, wherein the first communication network is a mobile communication network and the quality-of-service mapping information associated with the terminal includes at least one of the following information: a destination port number, a protocol identifier, a PDP context identifier in a GPRS system, a name of an access point in a GPRS system and a Diffserv class.

30. Terminal according to any one of claims 24 to 29, wherein the sending procedure is automatically initiated by a service application executing on the terminal .

31. Method for sending, by a terminal, quality-of-service mapping information and setting it in a network node, wherein the network node is configured to interface a first communication network using a first quality- of-service mechanism with a second communication network using a second quality-of- service mechanism differing from the first quality-of- service mechanism, and to use the quality-of-service mapping information for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet; the method including a sending procedure for sending, by the terminal, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal; a receiving procedure for receiving, by the network node, from a terminal and through a signalling communication channel, quality-of-service mapping information associated with the terminal; and a storing procedure for storing, by the network node, the quality-of-service mapping information in association with an identifier identifying the terminal .

32. System comprising a terminal and a network node, wherein the terminal is configured for sending quality-of-service mapping information to be set in the network node, wherein the network node is configured to interface a first communication network using a first quality-of-service mechanism with a second communication network using a second quality-of- service mechanism differing from the first quality-of- service mechanism, and to use quality-of-service mapping information in the network node for assigning a quality-of-service to a data packet arriving at the network node depending on attributes associated with the data packet; the terminal including a sending unit for sending, to the network node and through a signalling communication channel, quality-of-service mapping information associated with the terminal; the network node including a receiver unit for receiving from the terminal and through a signalling communication channel, quality-of-service mapping information associated with the terminal; and a storing unit for storing the quality-of-service mapping information in association with an identifier identifying the terminal.

33. Computer program product comprising a program which, when executed on a network node, causes the network node to perform the method according to any one of claims 1 to 8.

34. Computer program product comprising a program which, when executed on a terminal, causes the terminal to perform the method according to any one of claims 17 to 23.