KR100661512B1 - A method for supplying differentiate service in the atm mpls network - Google Patents

Abstract

A method for providing a differentiate service in an ATM MPLS(Multi Protocol Label Switch) network is provided to remarkably reduce the frequency of MPLS signaling processing and to save network resources by creating DS(Differentiate Service) LSPs(Label Switch Paths) as many as the number of DS QoSs(Quality of Services), without the necessity of creating an LSP for every subscriber network. A routing system(100) for providing a differentiate service in an ATM MPLS network is comprised of a DS LSP controller(110) and a DS packet forwarding controller(120). The DS LSP controller(110) receives router address information, to which a destination subscriber network is connected, and DS QoS information, transmits/receives labels with an ATM MPLS network, and creates a DS LSP having ATM QoS corresponding to a DS. Then, the DS LSP controller(110) maps the DS QoS information to the created LSP, creates DS LSP traffic mapping information, and outputs it to the DS packet forwarding controller(120). The DS packet forwarding controller(120) has a DS packet forwarding table to store the DS LSP traffic mapping information. The DS packet forwarding controller(120) selects a DS LSP corresponding to router address information, to which the destination subscriber network of an input traffic is connected, and DS QoS information, adds a label to it, and executes ATM packet forwarding.

Description

A method for supplying differentiate service in the ATM MPLS network

1 is a schematic configuration diagram of a multi-protocol label switch (MPLS) network in the prior art;

2 is a flowchart illustrating a process for providing a Differentiate Service (DiffServ) in a conventional MPLS network.

3 is a diagram illustrating a schematic configuration of a traffic conditioner for differentiating service packet forwarding of FIG.

4 is a conceptual diagram of a differential service (DiffSer) packet forwarding process of FIG.

Figure 5 is a schematic block diagram of a differentiating service providing routing device of AMT MPS network according to the present invention,

6 is a flowchart illustrating a detailed process of a method for providing differentiation service of AMT MPS network of the present invention.

FIG. 7 is a flowchart illustrating a detailed process of generating a DS LSP of FIG. 6.

FIG. 8 is a flowchart illustrating a detailed processing of the DS packet forwarding process of FIG. 6.

Description of the main symbols in the drawings

1: ATM MPLS Network (ATM Multi Protocol Label Switch Network)

2: Label Edge Router (LER)

3: Label Switch Router (LSR)

4: link

5: Label Switch Path (LSP)

10: Traffic Conditioner

11: Classifier 12: Meter

13: Marker 14: Shaper

15: Watch / Scheduler

100: differentiated service providing router (DS Router)

110: differentiated service label switch path control unit (DS LSP control unit)

(Differentiate Service (DS) Label Switched Path controller)

111: operator input processing unit

112: differentiated service label switch path generation unit (DS LSP generation unit)

113: Differentiated Service Label Switch Route Traffic Mapping Configuration Section

(DS LSP Traffic Mapping Configuration)

120: Differentiation service packet forwarding unit (DS packet forwarding unit)

121: Differentiated service packet forwarding engine (DS packet forwarding engine)

122: Differentiation service packet forwarding table (DS packet forwarding table)

CR-LSP: Constraint based Label Switched Path

iBGP (interior Border Gateway Protocol) peer Address

The present invention relates to a Differentiate Service (DiffServ: Differentiate Service) in an Asynchronous Transfer Mode Multi Protocol Label Switch (ATM MPLS) network, and more particularly, to provide an LSP for providing a differentiated service in an ATM MPLS network. The present invention relates to a method for providing differentiation service of an AMT MPLS network that can be generated by a simple MPLS signaling procedure and then provide a differentiation service by an ATM MPLS packet.

The scalability of the network, including the increase in the number of routers and the increase in the number of router tables managed by the router, as well as the bandwidth to solve the traffic problem caused by the increase of Internet users, The combination of routing and ATM switching technology has been considered as a solution for high speed.

These considerations result in IP based on an overlay model, where nodes in Layer 3 and Layer 2 constitute separate logical planes, where routers recognize routers as routers and ATM switches as peers neighboring ATM switches. over ATM protocol.

An IP switching scheme of integrated routing, in which an ATM switch performs an IP routing function, is proposed during the aforementioned IP over ATM protocol.

Since then, the above-described IP switching schemes have been developed in various ways. In order to integrate these various techniques, the IP packet is combined with the link layer switching technique based on the concept of the unified label switching protocol in the IETF. A multiprotocol label switch (MPLS) is proposed. Here, LDP (Label Distribution Protocol) is defined for distribution of labels by MPLS signaling procedure in one MPLS network.

1 is a schematic configuration diagram of a multi-protocol label switch (MPLS) network in the prior art.

As shown in FIG. 1, the MPLS network 1 includes label edge routers (LERs) 2 located at the edge of the network to interwork with other networks or to accommodate subscribers, and the MPLS network. Label Switch Routers (LSRs) 3 located at the center of (1) and links 4 connecting them (2, 3).

The LER (2) at the entrance of the MPLS network (1) analyzes the header (including destination IP address) of the packet from another network to determine the LSP (5) to which the packet will be forwarded, and then the LSP (5). Encapsulate the label corresponding to the packet, and deliver it to the output interface corresponding to the LSP 5.

When the LSR (3) receives the encapsulated packet, the LSR (3) examines only that label, changes the label, and forwards it to the specified output interface. The LER (2) at the network exit removes the label of the arriving packet and forwards the packet to its destination.

The LSP 5 may be automatically generated when the LDP is interworked with the IP routing protocol. However, the LSP 5 may be forcibly set to satisfy a specific condition. Here, the specific condition includes a specification for network resources occupied by the LSP 5, such as a specification for the LSRs 3 through which the LSP 5 passes, or a bandwidth. The LSP configured to satisfy a specific condition is called a Constraint-based Label Switched Path (CR-LSP).

The MPLS described above does not perform a longest match algorithm using IP addresses in the router table to forward packets at the current router, but rather uses a fixed length called label based on label swapping. The packet is delivered by an exact match using a short identifier of. The label indicates a group of packets that are equally delivered by the nodes of the network. That is, packets having the same label value belong to the same group, and these groups of packets are transmitted in the same way in MPLS distinguished by the routing protocol, and such a group of packets is called Forwarding Equivalent Class (FEC).

As described above, packets from the same multiple application services form one packet flow, and these flows form a stream having the same FEC. One label refers to this same stream of FEC.

Recently, many real-time multimedia applications have emerged in the Internet such as Mbone and Internet phones that require end-to-end quality of service (QoS) guarantees. Accordingly, in order to support QoS required by real-time application service, IS (Integrated Service) method uses RSVP (Roesource Reservation Protocol) signaling protocol that makes resource reservation based on packet flow generated in real-time application. By providing permission control and resource reservation in advance, QoS-guaranteed services and best effort-type services are distinguished and provided. However, RSVP protocol, which reserves resources in each flow unit, has a scalability problem that increases complexity when the network size increases.

Accordingly, by providing differentiated services based on aggregation of flows rather than flow units, a new structure of differentiated service (Diffserv: "DS"), which is much simpler and applicable to large networks, is IETF DiffServ. Proposed by Workgroup (WG).

The above-described DS is a packet forwarding method in a Label Switched Router (LSR) determined by information on a DS byte of an IP packet (TOS (Type of Service) byte of IP v4 or Class Field byte of IP v6). PHB, traffic conditioner and domain service allocation policy are properly configured and combined to realize various services.

FIG. 2 is a flowchart illustrating a process for providing a Differentiate Service (DiffServ) in a conventional MPLS network, and FIG. 3 is a schematic configuration of a traffic conditioner for packet forwarding of the differentiated service of FIG. 2. FIG. 4 is a conceptual diagram of a DiffSer packet forwarding process of FIG. 2.

 As shown in FIG. 2, in order to provide a differentiated service in a conventional MPLS network, a DS subscriber network, in which negotiation and setting of a service level agreement (SLA) and a traffic conditioning agreement (TCA), is completed, is added by a routing protocol. A routing table is configured by performing a network information synchronization process of transmitting and receiving subscriber address information between routers (LER (2), LSR (3)) in the MPLS network (S1).

Next, routers (LER (2), LSR (30)) in the MPLS network exchange the label by MPLS signaling after driving the LDP protocol (S2).

Then, when DS information according to SLA and TCA information is input by the operator, several DS Per Hop Behaviors (PHBs) equal to the Forwarding Equivalence Class (FEC) having prefix information indicating the subscriber address of the traffic to receive the DS LER (2) to which subscriber network is connected by using PSC (PHB Scheduling Class) generated by redefining a class into one class, differentiated service LSP (DS LSP: Differentiate LSP) (E-LSP (EXP inferred LSP) through MPLS signaling. ) Or L-LSP (Label Only Inferred LSP). At this time, the MPLS signaling for generating the DS LSP performs a signaling procedure as many as the number of subscriber networks x number of DS classes (DS QoS) to generate a DS LSP. In this case, only the L-LSP is used in the ATM MPLS network because the EXP field of the label is not visible in the router (S3).

After the DS LSP is generated by the S3 process, a traffic mapping table for mapping subscriber information and DS information to the DS LSP corresponding to each service quality is performed to generate a DS traffic mapping table. The above-described DS traffic mapping table includes a destination address, service quality information (DiffServ (DS) quality (QoS) information), DS LSP label information, path, band information, priority information, and the like (S4).

After that, when traffic is input from the subscriber network, the packet forwarding unit reads DS quality information from the subscriber traffic from the header of the input packet, selects a DS LSP having a corresponding destination address and DS quality information, and forwards the packet. Forwarding is performed (S5).

For the packet forwarding by the above-described S5 process, the router apparatuses of the prior art include a classifier 11, a meter 12, a marker 13, and a classifier 11 as shown in FIG. A traffic conditioner 10 having a shaper 14 and a monitor / scheduler 15 is used to generate DS MPLS packets and then perform DS packet forwarding.

That is, as shown in Figure 4, when the MPLS packet having the general traffic (Encapsulation traffic) or label (Label) of the external subscriber network that is a non-MPLS packet is input, the input DS by checking the header information or label of the general traffic Detects and outputs a QoS compliant input PHB or an ATM service QoS compliant PHB (A).

Next, traffic conditioning such as classification, marking, shaping, monitoring, and scheduling is performed using the input PHB to generate an output PHB and generate a DSCP corresponding to the output PHB. That is, a packet arriving at an inlet Label Edge Router (LER) in a DS area means a packet forwarding service (a treatment for scheduling and discarding a packet) that will be received by all routers in the area. hop behavior). At this time, a set of packets that will receive the same packet forwarding service is called a bahavior aggregation (BA). All packets belonging to one BA are then given the same DSCP by a DS marker (DS byte marking). Core routers in the network refer to this DSCP field only when performing packet forwarding to perform appropriate scheduling and packet discarding for the corresponding packet. DSCPs and corresponding PHBs include Expedited Forwarding (EF), Assured Forwarding (AF), Default Forwarding (DF), and Class Selector (CS). The EF PHB should be processed with the smallest delay, jitter, and smallest packet discard probability of all PHBs. The AF PHB is actually a group of PHBs, consisting of a total of 12 PHBs with four classes and three relative packet discard probability levels within each class. Classes represent priorities in scheduling and levels represent priorities in terms of discarding discarded packets. The DF PHB is a PHB for continuing to support the best effort forwarding service currently received by the packet on the Internet (B).

Next, the MPLS network allocates a DS LSP corresponding to the generated output PHB and adds a label of the corresponding DS LSP to perform packet forwarding (C).

In contrast, when forwarded to an external subscriber network instead of an MPLS network, an encapsulation including the corresponding PHB information is included in the packet information and then output to the subscriber network such as a general IP network (D).

In other words, in the prior art, DS (DiffServ) support in MPLS network uses LSP as a DS (DiffServ) tunnel.In this case, in order to implement MPLS DiffServ, a function is provided to drill an LSP tunnel according to DS (DiffServ) information. Mapping traffic to LSPs through classification, traffic conditioning, scheduling / policing, and forwarding packets from LSPs from each LSR through BA classification, monitoring, and scheduling according to DiffServ information. Function is required.

 That is, in case of applying the DS service as described above, each LSR determines the PHB through the VPI / VCI (label) of the incoming ATM cell, and accordingly, DiffServ QoS (Scheduling) Resource allocation and, if necessary, a policing (dropping) function.

However, the addition of the above-described functions for ATM cell forwarding in a conventional ATM MPLS network that is processed in hardware is currently not possible. Accordingly, in an ATM MPLS network, a LC (Label Controled) -ATM based router (LER, LSR) system transmits DiffServ traffic through an L-LSP tunnel. For this reason, the ATM MPLS network does not provide QoS by DiffServ as described above at the router, but only provides ATM service QoS.

At this time, as described in the above description of FIG. 2, in the prior art, in order to generate L-LSP for application of DS in ATM MPLS network, MPLS signaling processing is performed as much as (number of subscriber networks X DS QoS). In addition, since the corresponding number of L-LSPs must be generated, the number of L-LSPs to be generated increases when the number of subscriber networks increases, which causes a significant increase in the number of MPLS signalings, thereby delaying the L-LSP generation procedure. In addition, there is a problem that waste of network resources for MPLS signaling occurs.

Accordingly, the present invention is to solve the above-mentioned problems of the prior art, when providing a differentiation service (Differentiate Service) in ATM MPLS network, differentiation service without performing unnecessary MPLS signaling procedure for generating L-LSP for each subscriber network Differentiate service by mapping ATM service QoS information corresponding to quality of service (DS QoS) and using iBGP peer address and DiffServ PHB (DS PHB) as address of LER connected to destination subscriber network. ATM to create differentiated service LSP (DS LSP) as many as the number of quality (QoS) and to perform differentiated service packet forwarding using destination iBGP peer address and DiffServ PHB of traffic inputted from differentiated service subscriber network Providing a method for providing differentiated services in AMP MPLS (Asynchronous Transfer Mode Multi Protocol Label Switch) network And for that purpose.

In order to achieve the above object, AMT MPLS (Asynchronous Transfer Mode Multi Protocol Label Switch) network of the present invention provides a differentiated service providing routing device, the router address information and the differentiated quality of service (DiffServ) connected to the destination subscriber network : Differentiate Service (hereinafter, referred to as "DS") information is inputted to generate a differentiated service LSP (DS LSP) having ATM service quality (ATM service QoS) corresponding to the differentiated service (DS Qos), and then generated LSP A differentiated service label switch path controller (hereinafter referred to as a "DS LSP controller") for mapping differentiated quality of service information to the controller; A Differentiated Service Packet Forwarding Table for storing the differentiated service traffic mapping information, and selecting a DS LSP corresponding to the router address information and the differentiated service quality information to which the destination subscriber network of the input traffic is connected; It is characterized in that it comprises a differentiated service packet forwarding unit (hereinafter referred to as "DS packet forwarding unit") for performing ATM packet forwarding after adding a label.

The differential service label switch path control unit (DS LSP control unit) includes an operator input processing unit which receives and outputs a differential service (DiffServ: Differentiate Service (DS)) information and a subscriber network address information input by an operator; Differentiated service label switch path generating a differentiated service label switch path (DS LSP) having ATM service quality (ATM service QoS) corresponding to the differentiated service information after transmitting and receiving a label for transmitting differentiated service traffic in the MPLS network. A generating section (hereinafter referred to as a "DS LSP generating section"); DS LSP traffic mapping information generated by mapping router address information and differentiated quality of service (DS QoS) information to which the destination subscriber network of the operator input subscriber network is connected to the ATM service quality corresponding DS LSP generated by the DS LSP generation unit A differential service label switch path traffic mapping setting unit (DS LSP traffic mapping setting unit) output to the DS packet forwarding unit; Characterized in that it comprises a.

The differentiated service label switch path controller (DS LSP controller) may further include a storage unit for storing subscriber network address information, label information, DS quality (QoS) information, and ATM service quality information.

The DS packet forwarding unit detects destination subscriber network access router address information by using DS QoS information and a destination subscriber network address from input traffic from the external subscriber network, and then converts the DS LSP traffic mapping information from the DS LSP traffic mapping information to the DS QoS. A DS packet forwarding engine that selects a DS LSP having a corresponding ATM quality of service and adds a label to perform DS packet forwarding; And a DS packet forwarding table for storing the DS LSP traffic mapping information.

A method for providing a differentiated service of an Asynchronous MPLS (ATM MPLS) network of the present invention for achieving the above object includes a router address information and a differentiated quality of service (DiffServ :) connected to a destination subscriber network. Differentiate Service (hereinafter referred to as "DS") information is inputted to create a differentiated service label switch path for generating a differentiated service LSP (DS LSP) having ATM service quality (ATM service QoS) corresponding to the differentiated service (DS Qos) Process (DS LSP generation process); A DS LSP traffic mapping process of generating DS LSP traffic mapping information by mapping the differentiated quality of service (DS QoS) information to a DS LSP having a corresponding ATM quality of service generated by the DS LSP generator; A DS packet forwarding step of performing ATM packet forwarding after selecting a DS LSP corresponding to router address information and differentiated quality of service information to which a destination subscriber network of the input traffic from the external subscriber network is connected, adding a label, and performing ATM packet forwarding; Characterized in that made.

The DS LSP generation process includes an ATM service quality mapping process of mapping the differentiated quality of service (DS QoS) information to the ATM quality of service (QoS) information; And a DS LSP tunnel generation process for generating a DS LSP tunnel using a router address and a DS PHB (DiffServ PHB) for accessing the destination subscriber network.

The DS packet forwarding process includes: a classification process of detecting a DS PHB from header information of a packet of traffic input from the subscriber network at an input interface and performing classification by SLA (TCA); A scheduling process of performing DS scheduling according to the detected DS PHB and delivering the same to an output interface; Selecting the DS PHB corresponding DS LSP from the output interface, adding the label of the selected DS LSP to generate an ATM MPLS packet, and then performing scheduling and monitoring according to the ATM service QoS of the selected DS LSP and outputting the same. DS forwarding process; characterized in that comprises a.

In the above-described present invention, the address of the router to which the destination subscriber network is connected is an iBGP peer address (iBGP peer address: interior Boarder Gateway Protocol peer address) as the address of the LER to which the destination subscriber network is connected.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

Figure 5 is a schematic block diagram of a differentiating service providing routing device 100 of AMT MPS network according to the present invention.

As shown in FIG. 5, the apparatus 100 for providing differentiated services of the ATM MPS network includes:

ATM corresponding to the DS Qos by receiving and sending the router address information and the differentiated quality of service (DiffServ: Differentiate Service, "DS") information connected to the destination subscriber network, and transmitting and receiving a label with the ATM MPLS network. After generating a differentiated service LSP (DS LSP) having a quality of service (ATM service QoS), the differentiated service quality information is mapped to the generated LSP to generate DS LSP traffic mapping information and output to the DS packet forwarding unit 120. A DS LSP controller (Differentiate Service Label Switch Path controller) 110;

 A Differentiated Service Packet Forwarding Table for storing the differentiated service traffic mapping information, and selecting a DS LSP corresponding to the router address information and the differentiated service quality information to which the destination subscriber network of the input traffic is connected; It is configured to include a; DS packet forwarding unit (Differentiate Service Packet Forwarding Controller 120) for performing ATM packet forwarding after adding a label.

The DS LSP control unit 100 may include a differential service (DiffServ: Differentiate Service, hereinafter, “DS”) including destination subscriber network address information (iBGP peer address) (iBGP (interior Boarder Gateway Protocol) peer address) input by the operator. Operator input processing unit 111 for receiving and outputting information and subscriber network address information; A DS LSP generation unit for generating a differentiated service label switch path (DS LSP) having an ATM service quality (ATM service QoS) corresponding to the differentiated service information after transmitting and receiving a label for transmitting differentiated service traffic in the ATM MPLS network. 112; Generated by mapping the router address information and the differentiated quality of service (DS QoS) information to which the differentiated service target destination subscriber network of the operator input subscriber network is connected to the ATM service quality corresponding DS LSP generated by the DS LSP generation unit 112. A DS LSP traffic mapping setting unit 113 for outputting DS LSP traffic mapping information to the DS packet forwarding unit 102; And a storage unit 114 storing subscriber network address information, label information, DS quality of service (QoS) information, and ATM service quality information.

The operator input processing unit 111 receives destination subscriber network address information (iBGP peer address) (iBGP (interior Boarder Gateway Protocol) peer address) corresponding differentiation service (DiffServ: Differentiate Service, DS) information, and then receives DS quality information ( QoS is mapped to ATM Quality of Service (QoS) and then stored in storage 114. In this case, the mapping of the DS quality information (QoS) to the ATM quality of service (QoS) may be mapping of the EF service to a constant bit rate (CBR) service and the AF service to a variable bit rate (VBR) service.

The DS LSP generation unit 112 transmits and receives label information to be used for traffic transmission in the MPLS network through an operation of a routing protocol or an MPLS signaling protocol (LDP / CRLDP, RSVPTE). Save to 114. Thereafter, without performing MPLS signaling for all subscriber networks included in all subscriber network addresses included in the routing table, on the path of the LER to which the destination subscriber network is connected for each DS quality (QoS) information provided for each destination subscriber network. After performing the MPLS signaling with the included routers, the label is transmitted and received to generate a DS LSP having an ATM service quality corresponding to the corresponding DS quality using the received label information.

That is, the DS LSP generation unit 112 drills through the DS LSP tunnel using the iBGP peer address and the DS PHB (DiffServ PHB) as the address of the LER to which the destination subscriber network is used when setting the routing protocol. At this time, the LSP is set to guarantee the ATM service QoS that can satisfy the DS QoS. For example, EF service is mapped to CBR service and AF service is mapped to VBR service to create ATM connection (LSP) of the corresponding service class.

The DS LSP traffic mapping setting unit 113 provides a DS LSP that provides an ATM quality of service corresponding to the DS quality (QoS) of the subscriber network allocated for each iBGP peer address and the DS quality generated by the DS LSP generating unit 112. After performing the DS LSP traffic mapping to map the DS LSP traffic mapping information is generated and output to the DS packet forwarding unit 120.

The DS packet forwarding unit 120 detects DS QoS information and a destination subscriber network address from external input traffic and then, on the destination subscriber network access LER having an ATM quality of service corresponding to the DS QoS in the DS LSP traffic mapping information. A DS packet forwarding engine 121 for performing DS packet forwarding by selecting a DS LSP and adding a label; And a DS Packet Forwarding Table (122) for storing the DS LSP traffic mapping information.

In this case, the DS packet forwarding engine 121 classifies by SLA (TCA) at an input interface into which a packet of traffic from a subscriber network flows, and delivers it to an output interface by DS scheduling (DiffServ Scheduling). The output interface performs scheduling and monitoring according to the ATM service QoS of the DS LSP tunnel formed between the destination subscriber network access LERs to be mapped.

As described above, the DS forwarded packet is forwarded according to the ATM service QoS at a later LSR node. In addition, the LSP end system (output LER) outputs a schedule to the subscriber in the subscriber network after scheduling (Scheduling) by the transmission method of the subscriber network according to the DS PHB again at the input interface.

6 is a flowchart illustrating a detailed process of a method for providing differentiation service of AMT MPS network of the present invention.

The process of FIG. 6 will be described with reference to FIGS. 1 and 5 as follows.

As shown in FIG. 1, when a new subscriber network having completed negotiation and setting up of a service level agreement (SLA) and a traffic conditioning agreement (TCA) is added to the ATM MPLS network, nodes (LER (2) and LSR of the ATM MPLS network) are added. (3)) configures a routing table by performing a network information synchronization process of transmitting and receiving subscriber address information by a routing protocol (S10).

Next, the LERs 2 in the ATM MPLS network exchange the labels by MPLS signaling after driving the LDP protocol (S20).

Subsequently, when the subscriber network address and DS information according to the SLA and TCA information are input by the operator later, iBGP peer as the address of the destination subscriber network access LER after mapping the DS quality (QoS) information and the ATM quality of service (QoS) information. A DS LSP is generated using the address (S30).

7 is a flowchart illustrating a detailed process of generating the DS LSP described above. Referring to FIG. 7, the DS LSP generation process of S30 will be described in more detail as follows.

According to the SLA and TCA information including the address (iBGP peer address) (iBGP (interior Boarder Gateway Protocol) peer address) of the LER to which the destination subscriber network for differentiation service is connected by the operator as in S30 of FIG. 6. After receiving Differentiate Service (DiffServ) information and subscriber network address, DS quality information (QoS) is mapped to ATM quality of service (QoS). In this case, the mapping of the DS quality information (QoS) to the ATM quality of service (QoS) may include mapping an EF service to a constant bit rate (CBR) service and an AF service to a variable bit rate (VBR) service. Same (S31). And,

Next, the LER in charge of accessing the subscriber network generates a DS LSP using the iBGP peer address of the LER to which the subscriber network to which the differentiated service destination is connected and the ATM quality of service information corresponding to the DS PHB (DiffServ PHB). At this time, the DS LSP corresponding to the generated iBGP peer address is generated as many as the quality of service (QoS) for providing the DS. That is, the above-described DS LSP is not generated for each subscriber network for providing DS service, but if the number of DS quality (QoS) with the destination subscriber network assigned to the subscriber network is four, the ATM service quality corresponding to each DS quality is provided. Four DS LSPs satisfying the two are generated (S32).

Next, when the DS LSP is generated by the above-described S30 process, each DS quality is obtained by using the iBGP peer address and DS information (DS PHB) of the LER to which the subscriber network is connected. The DS LSP traffic mapping information generated by performing the DS traffic mapping that maps the corresponding traffic to the DS LSP is stored in the DS traffic mapping table. The above-described DS traffic mapping table includes a destination address, a destination subscriber network access router address (iBGP peer address), quality of service information (DiffServ (DS) quality (QoS) information), label information for a DS LSP path, bandwidth information, and priority. Information and the like (S40).

After that, when traffic is input from the subscriber network, the packet forwarding unit listens to the DS quality information (DiffServ PHB) of the subscriber traffic from the header of the input packet, and then the address and DS quality information (DiffServ PHB) of the LER connected to the corresponding destination subscriber network. DS LSP is selected to add the label to generate the ATM MPLS packet and then forward the DS packet forwarding (S50).

8 shows a detailed process of the above-described DS packet forwarding process of S50.

As shown in FIG. 8, in the above-described DS packet forwarding process of the S50 process, when traffic is inputted from the subscriber network, DS service quality information (DS PHB) is included in the header information of the traffic packet inputted at the input interface where the packet of traffic is introduced. And after detecting the address (iBGP peer address) of the LER to which the destination subscriber network is connected, classification by SLA (TCA) is performed (S51).

Next, DS scheduling is performed according to the detected DS PHB and then transferred to the output interface (S52).

On the output interface, select a DS quality-compliant DS LSP, add a label for the selected DS LSP to generate an ATM MPLS packet, and then schedule and monitor (scheduling and policing) according to the ATM service QoS for the selected DS LSP tunnel. After performing the DS forwarding through the output interface corresponding to the selected DS LSP (S53).

The processing as described above is performed at the input LER of the ATM MPLS network. If the input LER of ATM MPLS network forwards and outputs the ATM MPLS packet by the above-described process, the LSR node is forwarded according to the ATM service QoS, and the LSP end system (output LER: Egress LER) is inputted. The interface performs scheduling according to DS PHB according to ATM service QoS and DS QoS mapping information and outputs it to subscriber network.

In the above-described present invention, when providing a differential service (DS) in an ATM MPLS network, as in the prior art, the MPLS signaling is not performed as much as (the number of DS QoS for each subscriber number X) and is merely a destination subscriber. After creating DS LSPs as many as the number of routers and DS QoS connected to the network, the traffic of the same destination subscriber network with the same DS QoS as the router address (iBGP peer address) to which the subscriber network is connected is selected. By selecting and performing forwarding according to the DS QoS-adaptive ATM service QoS, a differentiated service (DS) can be provided in an ATM MPLS network.

That is, the present invention described above does not generate all LSPs for subscriber networks as in the prior art to support differentiation service (DS) in ATM MPLS network, but generates DS LSPs as many as DS QoS, compared to the prior art. It significantly reduces the number of MPLS signaling processing, which provides the effect of saving network resources.

In addition, since the present invention described above can reduce the number of LSP connection management in the MPLS network as described above, even when applied to a large subscriber network, there is an effect that the scalability problem does not occur.

Claims (3)

The destination subscriber network receives the router address information and the differentiated quality of service (DiffServ: Differentiate Service, hereinafter referred to as "DS") information connected to each other, and has ATM quality of service (ATM service QoS) corresponding to the differentiated service (DS Qos). Creating a differentiated service label switch path for generating a differentiated service LSP (DS LSP); Differentiated service label switch traffic mapping process (DS LSP traffic mapping) for generating DS LSP traffic mapping information by mapping the differentiated quality of service (DS QoS) information to a DS LSP having a corresponding ATM quality of service generated by the DS LSP generation unit Process); Differentiated service packet forwarding process for performing ATM packet forwarding after selecting a DS LSP corresponding to router address information and differentiated quality of service information to which the destination subscriber network of the input traffic from the external subscriber network is connected, and adding a label Forwarding process); method for providing differentiation services of AMT MPS network comprising a. The method of claim 1, wherein the DS LSP generation process, An ATM quality of service mapping process for mapping the differentiated quality of service (DS QoS) information to the ATM quality of service (QoS) information; Providing a DS LSP tunnel for creating a DS LSP tunnel using a router address and DS PHB (DiffServ PHB) that is in charge of accessing the destination subscriber network; providing a differentiated service of AMT MPS network Way. The method of claim 1, wherein the DS packet forwarding process, A classification process of detecting a DS PHB from header information of a packet of traffic input from the subscriber network at an input interface and performing classification by SLA (TCA); A scheduling process of performing DS scheduling according to the detected DS PHB and delivering the same to an output interface; Selecting the DS PHB corresponding DS LSP from the output interface, adding the label of the selected DS LSP to generate an ATM MPLS packet, and then performing scheduling and monitoring according to the ATM service QoS of the selected DS LSP and outputting the same. DS forwarding process; method for providing differentiation service of AMT MPS network comprising the.

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