CN101808005B

CN101808005B - network quality evaluation method, device and system

Info

Publication number: CN101808005B
Application number: CN2009100773225A
Authority: CN
Inventors: 刘涛; 苏良峰; 马根伟
Original assignee: Asiainfo Linkage China Co ltd
Current assignee: Asiainfo Technologies China Inc
Priority date: 2009-02-17
Filing date: 2009-02-17
Publication date: 2012-05-02
Anticipated expiration: 2029-02-17
Also published as: CN101808005A

Abstract

The invention discloses a network quality evaluation method, a device and a system, wherein the method comprises the following steps: MPLS VPN functionality is enabled in the network and two test VPNs are opened: VPN1 and VPN 2; the method comprises the steps that a detector is only arranged on a source node in a network, and the MPLS VPN loopback function is enabled on a destination node without the detector; planning the routes of the VPN1 and the VPN2 of each node, and storing a routing table of the VPN1 and the VPN2 of each node; the source node forwards the initial test flow sent by the detector to the destination node, and the destination node loops the final test flow back to the source node; and the source node provides the final test flow to an acquisition and analysis center, and the acquisition and analysis center analyzes the final test flow and the initial test flow stored in advance and evaluates the network quality by utilizing analysis data. The invention has the advantages of strong expandability, simple management and low cost.

Description

Network quality evaluation method, device and system

Technical Field

The invention relates to the technical field of computer networks, in particular to a network quality evaluation method, device and system.

Background

The research on the quality of service assurance mechanism of the IP network is a common hotspot in the internet field and the telecommunication field, and is one of the bases for providing communication services such as voice, video, data and the like on the IP network. Currently, various specific technologies and related solutions are proposed in the industry, and these solutions have respective technical features and application ranges, and when they are applied to the construction of IP networks and the environment of IP multi-service support, the specific application effects are different. In such situations, there is increasing interest in measuring, analyzing and evaluating network performance of IP networks.

The IP network performance monitoring technology mainly relates to selection of measurement parameters of IP network performance, determination of measurement indexes, measurement methods of specific parameters (including arrangement of measurement points, sampling methods of measurement results, and the like), evaluation methods of network performance, and the like.

An effective approach is to deploy an independent network quality monitoring system that monitors the quality of the network by simulating traffic flow. In the scheme, a distributed deployment detector and centralized analysis working mode is generally adopted, namely, a network performance detector is deployed at each node of a network, test flow occurs among the performance detectors, test results are uploaded to a collection and analysis center in a centralized manner, and the collection and analysis center calculates and analyzes the measurement results.

Referring to fig. 1, a schematic diagram of a network quality evaluation system taking a star network structure as an example is shown, where a collection analysis center is arranged at a node 1 for collecting and analyzing test data, detectors are deployed between the node 1 and other nodes (node 2, node 3.. node 6), detection traffic occurs between the node 1 and other node detectors periodically, and the detection data is collected to the collection analysis center for analysis. For a mesh network, the schematic diagram of the network quality evaluation system is shown in fig. 2, and similar to fig. 1, there are as many nodes as there are probes to be deployed.

In the conventional test scheme shown in fig. 1, the number of probes is proportional to the number of links (multiple physical transmissions between the same pair of nodes are taken as one link), for example, a network in which one node connects to 10 other nodes and 10 links needs to deploy 10 probes if the quality of all 10 links is to be detected. When the network scale is expanded to 1 node to connect with 100 other nodes and 100 links, 100 probes need to be deployed. Therefore, the scheme has poor expandability, complex management and high cost.

Disclosure of Invention

The invention provides a network quality evaluation method, a device and a system, which aim to solve the problems of poor expandability and the like of the existing scheme.

Therefore, the embodiment of the invention adopts the following technical scheme:

a network quality assessment method, comprising:

enabling MPLS VPN functionality in the network and opening two test VPNs: VPN1 and VPN 2; the method comprises the steps that a detector is arranged only on a source node in the network, and an MPLS VPN loopback function is enabled on a destination node without the detector by connecting a first port and a second port of the destination node, which belong to VPN1 and VPN2 respectively;

planning the routes of the VPN1 and the VPN2 of each node by adopting a sub-network dividing mode or a sub-network non-dividing mode, and storing a route table of the VPN1 and a route table of the VPN2 of each node;

the source node forwards the initial test flow sent by the detector to the destination node according to a routing table of the destination node, and the destination node loops the final test flow back to the source node according to the routing table of the destination node;

and the source node provides the final test flow to an acquisition and analysis center, the acquisition and analysis center analyzes and compares the final test flow with the initial test flow stored in advance, and the network quality is evaluated by using the analyzed and compared data.

Preferably, the network is a star network, a mesh network or a hybrid network.

A network quality evaluation system comprises a source node, a destination node, a detector and an acquisition and analysis center, wherein the MPLS VPN function is enabled in the network, and two test VPNs are opened: VPN1 and VPN 2; the method comprises the steps that a detector is arranged only on a source node in the network, and an MPLS VPN loopback function is enabled on a destination node without the detector by connecting a first port and a second port of the destination node, which belong to VPN1 and VPN2 respectively;

the source node is used for forwarding the initial test flow sent by the detector to the destination node according to a self routing table;

the destination node is used for looping back the final test flow to the source node according to a routing table of the destination node;

and the acquisition and analysis center is used for analyzing and comparing the final test flow provided by the source node with the initial test flow stored in advance and evaluating the network quality by using the analyzed and compared data.

Preferably, the source node includes:

the initial test flow forwarding unit is used for forwarding the initial test flow sent by the detector to a destination node according to a routing table pre-stored by the initial test flow forwarding unit;

the final test flow receiving and forwarding unit is used for receiving the final test flow looped back from the destination node and forwarding the final test flow to the acquisition and analysis center;

the destination node includes:

the initial test flow receiving unit is used for receiving an initial test flow transmitted by the detector and forwarded by the source node;

and the final test flow sending unit is used for looping back the final test flow to the source node according to a routing table pre-stored by the final test flow sending unit.

Preferably, the network is a star network, a mesh network or a hybrid network.

Therefore, the invention adopts the scheme that one point or local point is adopted to deploy the detector, other nodes adopt the MPLS VPN loopback technology, and the number of the detectors is irrelevant to the number of the network nodes, so the invention has strong expandability, simple management and low cost.

In addition, the invention is suitable for various network structures such as star type, mesh type, hybrid type and the like. In a star network structure, only a detector is required to be deployed at a central node, a remote end is not required to be deployed, and the number of detectors is irrelevant to the number of remote end nodes; under the mesh network structure, the number of the detectors can be reduced by half compared with the prior art.

Drawings

FIG. 1 is a schematic diagram of a prior art star network quality assessment system;

FIG. 2 is a diagram of a prior art mesh network quality assessment system;

FIG. 3 is a diagram of a prior art MPLS VPN networking;

FIG. 4 is a schematic diagram of a system for star network quality assessment according to the present invention;

FIG. 5 is a flow chart of a network quality assessment method of the present invention;

fig. 6 is a schematic diagram of a mesh network quality evaluation system according to the present invention;

fig. 7 is a schematic diagram of the internal structure of the network quality evaluation device according to the present invention.

Detailed Description

The invention adopts MPLS (Multi-Protocol Label Switch, Multi-Protocol Label switching) VPN (Virtual Private Network) loopback technology to realize Network quality test, which can effectively reduce the number of detectors and has good expandability.

MPLS is a new generation IP backbone network switching standard proposed by IETF, and is an integrated IP over ATM (Asynchronous Transfer Mode) technology. It integrates the advantages of IP routing technology flexibility and ATM simplicity, introduces MPLS connection-oriented attribute in connectionless-oriented IP network, and provides label switching service similar to virtual circuit.

Fig. 3 is a schematic diagram of MPLS VPN networking. MPLS VPNs include three types of routers: CE router, PE router and P router. Wherein, the CE router is a client router and provides the connection to the PE router for the user; the PE router is an operator edge router, that is, a Label Edge Router (LER) in the MPLS network, and is responsible for forwarding VPN data from a CE router or a Label Switched Path (LSP) after processing the VPN data according to stored routing information, and exchanging routing information with other PE routers; the P router is an operator network backbone router, i.e., a Label Switched Router (LSR) in an MPLS network, which transparently forwards VPN data according to an outer label of a packet, and maintains only routing information to the PE router and not VPN-related routing information. MPLS VPNs are classified into three-layer MPLS VPNs and two-layer MPLS VPNs according to whether a PE router participates in routing of a customer. Among them, the three-layer MPLS VPN uses BGP (Border Gateway Protocol) to distribute routing information among PE routers and uses MPLS technology to transfer data among VPN sites, and is also called BGP/MPLS VPN.

Fig. 4 is a schematic diagram of a system for evaluating the quality of a star network implemented by using the MPLS VPN loopback technique according to the present invention. Taking fig. 4 as an example, a detector is deployed at a node 1, the detector sends out n groups of test flows (a source IP address 1-1 and a destination IP address 2-1 of the test flow 1, a source IP address 1-2 and a destination IP address 2-2 of the test flow 2; a source IP address 1-n and a destination IP address 2-n of the test flow n), a node 2 to a node 6 are provided with an "MPLS VPN loopback" function to ensure that the test flow 1 sent from the detector of the node 1 passes through the node 2, the test flow 2 passes through the node 3, ·, and the test flow n passes through the node n +1 and returns to the detector of the node 1, the detector of the node 1 sends out a test result to an acquisition and analysis system, the network quality is monitored and evaluated by comparing the sent and received test flows through a certain existing algorithm.

Referring to fig. 5, it is a flowchart of the network quality evaluation method of the present invention, which includes:

s501: enabling MPLS VPN function in the network to be tested, and opening two test VPNs: VPN1 and VPN 2; setting a detector at a source node in a network to be tested, and enabling an MPLS VPN loopback function at a destination node without the detector;

s502: planning the routes of the VPN1 and the VPN2 of each node, and storing a routing table of the VPN1 and the VPN2 of each node;

s503: the source node forwards the initial test flow sent by the detector to the destination node according to a routing table stored by the destination node, and the destination node loops the final test flow back to the source node according to the routing table;

s504: and the source node provides the final test flow to an acquisition and analysis center, the acquisition and analysis center analyzes the final test flow and the initial test flow which is stored in advance, and the network quality is evaluated by utilizing the analysis data.

As those skilled in the art understand, the networks can be divided into a star network, a mesh network, and a hybrid network combining star and mesh networks according to their configuration shapes, and the method embodiment of the present invention will be described in detail below by taking the star network in fig. 4 as an example.

1. VPN planning

The MPLS VPN function is deployed in the tested network, and 2 testing VPNs are opened: VPN1 and VPN 2.

At the source node 1, the probe accesses different physical ports of the node 1 router, such as port 1-1 and port 1-2: port 1-1 belongs to VPN1, and port 1-2 belongs to VPN 2; in other destination nodes (node 2 to node 6), respective first ports (port 2-1 of node 2, port 3-1 of node 3, port 4-1 of node 4, port 5-1 of node 5, and port 6-1 of node 6) are planned to VPN1, respective second ports (port 2-2 of node 2, port 3-2 of node 3, port 4-2 of node 4, port 5-2 of node 5, and port 6-2 of node 6) are planned to VPN2, and two ports of the destination nodes belonging to VPN1 and VPN2 are connected, that is, MPLS VPN loopback function of the destination node is enabled.

The VPN planning results for the system shown in fig. 4 are shown in table 1:

TABLE 1

Network node	VPN1 port	VPN2 port
			Node 1	Port 1-1	Port 1-2
Node 2	Port 2-1	Port 2-2
			......	......	......
Node 6	Port 6-1	Port 6-2

2. Route planning

The more common route planning comprises two modes, wherein the mode 1 is realized by dividing subnets, the mode 2 is realized by not dividing subnets, and the mode 2 has simpler address planning.

Described separately below.

(2.1) planning method 1

The ports 1-1 and the VPN1 of the node 1 plan IP network segments 1-1 to 1-n (n represents the number of links), and the ports 1-2 and the VPN2 plan IP network segments 2-1 to 2-n (n represents the number of links).

The planning implications are shown in table 2:

TABLE 2

VPN name	Port numbering	Planning an IP network segment
			VPN1	Port 1-1	IP network segments 1-1, 1-2
VPN2	Port 1-2	IP segments 2-1, 2-2

On a node 1 router, the route from an IP network segment 1-1 to an IP network segment 1-n is distributed to a VPN1, the route from the IP network segment 2-1 to the IP network segment 2-n is distributed to a VPN2, other destination node routers VPN1 learn the route from the IP network segments 1-1 to 1-n and the route from the VPN2 to the IP network segments 2-1 to 2-n, and the next hop of the routes points to the node 1 router.

Connecting the routing between the IP network segment 1-1 and the IP network segment 2-1 between the node 2 router VPN1 and the VPN2, wherein one implementation mode is to operate a static routing protocol between loop-back links of the VPN1 and the VPN2 (the other implementation mode is to operate a dynamic routing protocol between loop-back links of the VPN1 and the VPN 2), a static routing and a next-hop routing pointing to the port 2-2 of the IP network segment 2-1 are configured in the VPN1, and the routing is issued to the VPN 1; a static route to IP sub-segment 1-1 is configured within VPN2, the route next hop is directed to port 2-1, and the route is published to VPN 2. The routing planning of other destination nodes is similar to that of node 2 and will not be described again. Thus, referring to tables 3 to 6, routing tables of the local VPN1 and the VPN2 of the node 1, the node 2, the node 3,.. and the node n are shown.

Table 3 (local VPN1, VPN2 routing table of node 1)

Table 4 (local VPN1, VPN2 routing table of node 2)

VPN name	Destination IP network segment	Routing next hop
			VPN1	IP network segment 2-1	Port 2-2
VPN2	IP network section 1-1	Port 2-1

Table 5 (local VPN1, VPN2 routing table of node 3)

VPN name	Destination IP network segment	Routing next hop
			VPN1	IP network section 2-2	Port 3-2
VPN2	IP network section 1-2	Port 3-1

Table 6 (local VPN1, VPN2 routing table of node n)

VPN name	Destination IP network segment	Routing next hop
			VPN1	IP network segment 2-n	Port n-2
VPN2	IP network section 1-n	Port n-1

(2.2) planning mode 2

In the node 1, the router port 1-1 and the VPN plan IP network segment 1 comprise an IP sub-network segment 1-1 to an IP sub-network segment 1-n (n represents a link), and the port 1-2 and the VPN2 plan an IP network segment 2 comprising an IP sub-network segment 2-1 to an IP network segment 2-n (n represents a link).

The planning implications are shown in table 7:

TABLE 7

An IP network segment 1 route is distributed to a VPN1 and an IP network segment 2 route is distributed to a VPN2 on a node 1 router, a node 2-node n router VPN1 learns the route of the IP network segment 1 and the route of the IP network segment 2 learned by a VPN2, and the next hop of the routes points to the node 1 router.

The routing between the IP sub-network segment 1-1 and the IP sub-network segment 2-1 is communicated between the node 2 router VPN1 and the VPN2, one implementation mode is that a static routing protocol (a dynamic routing protocol can be operated) is operated between cheering links of the VPN1 and the VPN2, the static routing and the next hop of the routing to the IP sub-network segment 2-1 are configured in the VPN1, and the routing is issued to the VPN 1; a static route to IP sub-segment 1-1 is configured within VPN2, the route next hop is directed to port 2-1, and the route is published to VPN 2.

Thus, referring to tables 8 to 11, routing tables of the local VPN1 and the VPN2 of the node 1, the node 2, the node 3,.. and the node n are shown.

Table 8 (local VPN1, VPN2 routing table of node 1)

Table 9 (local VPN1, VPN2 routing table of node 2)

VPN name	Destination IP network segment	Routing next hop
			VPN1	IP subnet section 2-1	Port 2-2
VPN2	IP subnet section 1-1	Port 2-1

Table 10 (local VPN1, VPN2 routing table of node 3)

VPN name	Destination IP network segment	Routing next hop
			VPN1	IP subnet section 2-2	Port 3-2
VPN2	IP subnet section 1-2	Port 3-1

Table 11 (local VPN1, VPN2 routing table of node n)

VPN name	Destination IP network segment	Routing next hop
			VPN1	IP subnet section 2-n	Port n-2
VPN2	IP subnet sections 1-n	Port n-1

3. Test flow planning

For each test flow, the node 1 detector selects an IP address in the IP network segment 1-n or the IP sub-network segment 1-n as a source IP address (such as IP address 1-1) of the test flow, and selects an IP address in the IP network segment 2-n or the IP sub-network segment 2-n as a destination IP address (such as IP address 2-1) of the test flow.

An example of a test path for a probe initiating a test flow for node 1 is shown in Table 12.

TABLE 12

Test flow	Test path	Source IP address	Destination IP address
				Test flow 1	Node 1-node 2	IP address 1-1	IP address 2-1
Test flow 2	Node 1-node 3	IP address 1-2	IP address 2-2
				......	......	......	......
Test stream n	Node 1-node n	IP addresses 1-n	IP address 2-n

Taking test flow 1 as an example, the node 1 probe initiates an "initial test flow", the node 1 router queries the local VPN1 routing table (table 3 or table 8), data addressed to IP address 2-1 is forwarded to the node 2 router, the node 2 router queries the local VPN1 routing table (table 4 or table 9), data addressed to IP address 2-1 is forwarded to port 2-2 of the node 2 router, data enters VPN2, the node 2 router queries the local VPN2 routing table (table 4 or table 9), data addressed to IP address 2-1 is forwarded to the node 1 router, the node 1 router queries the local routing table (table 3 or table 8), the "final test flow" node 1 probe is issued to complete the node 1 to node 2 testing, then the probe provides the initial test flow and the final test flow to the collection and analysis center, the acquisition and analysis center adopts a certain algorithm to compare and analyze the initial test flow and the final test flow, and utilizes the analysis data to evaluate the network quality. Similarly, the test procedure of the test flows 2 to n is similar to that of the test flow 1, and is not described herein again.

Fig. 6 is a schematic diagram of a network quality evaluation system with a mesh structure, in which, for nodes 1 to 4, probes are only required to be arranged on node 1 and node 3 as source nodes, and probes are not required to be arranged on node 2 and node 4 as destination nodes, and a MPLS VPN loopback function needs to be started, so that a test flow can be looped back to the source node to complete a network test.

Corresponding to the method, the invention also provides a network quality evaluation device and a network quality evaluation system.

Referring to fig. 7, the internal structure of the apparatus provided by the present invention and located at the source node side is shown. The apparatus may refer to a source node device itself, or may be a functional entity located inside a source node, and may be implemented by hardware, software, or a combination of hardware and software.

For a network applying the device, the MPLS VPN function needs to be enabled, and two test VPNs are opened: VPN1 and VPN 2; the method comprises the steps that a detector is arranged only on a source node in the network, and the MPLS VPN loopback function is enabled on a destination node without the detector.

Wherein, the network is a star network, a mesh network or a mixed network.

As can be seen from fig. 7, the apparatus includes:

an initial test flow forwarding unit 701, configured to forward an initial test flow sent by a detector to a destination node according to a routing table pre-stored in the initial test flow;

a final test flow receiving and forwarding unit 702, configured to receive a final test flow looped back from a destination node; and forwarding the final test flow to an acquisition and analysis center.

Referring to fig. 7 again, the internal structure of the device located at the destination node side according to the present invention is shown. The apparatus may refer to a destination node device itself, or may be a functional entity located inside a destination node, and may be implemented by hardware, software, or a combination of hardware and software.

Wherein, the network is a star network, a mesh network or a mixed network.

As can be seen from fig. 7, the apparatus at the destination node includes:

an initial test flow receiving unit 801, configured to receive an initial test flow sent by a probe forwarded by a source node;

a final test flow sending unit 802, configured to loop back the final test flow to the source node according to a routing table pre-stored in the final test flow sending unit.

The network quality evaluation system provided by the invention comprises a source node, a destination node, a detector and an acquisition and analysis center. The network may comprise a star network, a mesh network, or a hybrid network.

In particular, MPLS VPN functionality is enabled in the network and two test VPNs are opened: VPN1 and VPN 2; the method comprises the steps that a detector is arranged only on a source node in the network, and the MPLS VPN loopback function is enabled on a destination node without the detector.

Wherein,

For the source node, it internally includes (see fig. 7):

a final test flow receiving and forwarding unit 702, configured to receive a final test flow looped back from a destination node; forwarding the final test flow to an acquisition and analysis center;

for the destination node, it internally comprises (see fig. 7):

In addition, the invention is suitable for various network structures such as star type, mesh type, hybrid type and the like. In a star network structure, only the detectors are deployed at the central node, the detectors are not deployed at the remote nodes, and the number of the detectors is irrelevant to the number of the remote nodes; under the mesh network structure, the number of the detectors can be reduced by half compared with the prior art.

Those skilled in the art will appreciate that the processes of implementing the methods of the above embodiments may be implemented by hardware associated with program instructions, and the program may be stored in a readable storage medium, and when executed, the program performs the corresponding steps of the above methods. The storage medium may be as follows: ROM/RAM, magnetic disk, optical disk, etc.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A method for network quality assessment, comprising:

2. The method of claim 1, wherein the network is a star network, a mesh network, or a hybrid network.

3. A network quality evaluation system comprises a source node, a destination node, a detector and an acquisition and analysis center, and is characterized in that the MPLS VPN function is enabled in the network, and two test VPNs are opened: VPN1 and VPN 2; the method comprises the steps that a detector is arranged only on a source node in the network, and an MPLS VPN loopback function is enabled on a destination node without the detector by connecting a first port and a second port of the destination node, which belong to VPN1 and VPN2 respectively;

4. The system of claim 3,

the source node includes:

the destination node includes:

5. System according to claim 3 or 4, characterized in that said network is a star network, a mesh network or a hybrid network.