Between Resilient Packet Ring, realize method and the elastic packet loop network that message is transmitted
Technical field:
The invention belongs to the data transmission network communications field, relate in particular to a kind of method that between a plurality of RPR rings, realizes the message forwarding, and this network.
Background technology:
RPR (Resilient Packet Ring, Resilient Packet Ring) is a kind of two layers of medium access control (MAC) technology that IEEE 802.17 working groups formulate, and can be used for local area network (LAN), metropolitan area network and wide area network.RPR and media independent can use ethernet physical layer and SDH, SONET physical layer.
The twin nuclei that RPR is made up of a pair of reciprocal little ring, as shown in Figure 1, two little rings are referred to as little ring 0 (ringlet0) and little ring 1 (ringlet1) respectively, and they transmit control signal for the other side mutually when data signal.Each node identifies with one 48 bit MAC Address on the ring.
RPR have bandwidth statistic multiplexing, automatic topological discover, fast ring protection switch, characteristics such as fair algorithm; but can only be applied to single little ring; when the RPR of Access Layer or convergence layer ring need be pooled to core RPR ring; when promptly needing to provide transannular professional, only utilize existing RPR technology to finish.
Utilize Layer 2 switch can connect two different RPR rings, but such scheme can be subjected to the restriction of network size, because all must comprise overall information (all mac address informations in the network) at each layer 2-switched lane database, network size is big more, need the information of storage just many more, and the grouping of all transannulars makes the performance of the space reuse that RPR itself has reduce greatly all in whole ring cocycle.
Perhaps utilize three-layer equipment (as ip router) two RPR can be encircled interconnected, such scheme and allow three layers of connection end to end, and generally speaking, most of user only needs two layers service.
Above scheme all needs service provider to remove to buy the equipment of an outside, takies its machine room space, has increased the complexity of management, and if utilize three-layer equipment interconnected, has also needed to learn user's routing iinformation.
" method of interconnected a plurality of RPR ring in wide area RPR network " (CN1428979A) discloses the interconnected method of a kind of RPR, by distribute to the suitable loop sign Ring_ID of RPR ring according to the structure of classification tree, the communication that only meets between the different RPR rings in the network of structure of classification tree just is allowed to.
This method is necessary for RPR ring and determines special tree structure, and the communication path between the RPR ring can only carry out along tree structure, has influenced the speed and the degree of freedom of communication.
Summary of the invention:
The object of the present invention is to provide a kind of simple and easy to do, with low cost between the RPR ring method of transannular forwarding information, and this RPR network.
The method that between a plurality of RPR rings, realizes the message forwarding of the present invention, each RPR ring directly links to each other with a gateway at least; Every gateway directly links to each other with two or more RPR rings; Each RPR ring can comprise a gateway and several fringe nodes, perhaps includes only gateway, and every fringe node and gateway have MAC Address separately; By control plane, set up the label switched path of the whole network, each gateway is only stored local message; Each is treated that transannular E-Packets and comprises mac address information territory, a point of destination, and mac address information territory, a source station comprises that also a looped network closes the MPLS label information territory of distributing, and carries routing iinformation; Its step comprises
1) treats that the message that transannular is transmitted is the point of destination MAC Address with the MAC Address that this looped network closes, deliver to this looped network from sending node via this environment-development and close;
2) this looped network closes the MPLS label information territory according to this message, searches local routing table, determines the route of receiving node, closes with this looped network as receiving node place ring directly to link to each other, and then the point of destination MAC Address of this message is changed into the MAC Address of receiving node; Otherwise according to routing iinformation, change the point of destination MAC Address of this message on the path next gateway MAC Address, and change the MPLS label information into MPLS label information that this gateway distributes, until sending to the gateway that directly links to each other with receiving node place ring;
3) with the gateway that receiving node place ring directly links to each other message is sent to this ring, message is sent to receiving node via this ring.
The present invention uses the method for static configuration or the label switched path that agreements such as LDP, BGP are set up the whole network by control plane.
The present invention has at least a gateway directly to link to each other with all RPR rings.
MPLS label information of the present invention territory can also comprise class of service information
The present invention has two or more gateways on one or more RPR rings.
The RPR network of realizing the message forwarding between a plurality of RPR rings of the present invention comprises some RPR rings and at least one RPR gateway, and each RPR ring links to each other with a gateway at least; Every gateway directly links to each other with two or more RPR rings; Each RPR ring can comprise a gateway and several fringe nodes, perhaps includes only gateway, and every fringe node and gateway have MAC Address separately; Each gateway is only stored local message; Each RPR message comprises mac address information territory, a point of destination, and mac address information territory, a source station comprises that also a looped network closes the MPLS label information territory of distributing, and carries routing iinformation, and described gateway has the MPLS tag changeable path by function.
The present invention has at least a gateway directly to link to each other with all RPR rings.
MPLS label information of the present invention territory can also comprise class of service information, realizes user's QoS management and SLA are ensured.
The present invention has two or more gateways on one or more RPR ring, utilize that multinode is interconnected realizes the whole network protection.
The present invention solves the interconnected problem of a plurality of RPR rings by introducing the MPLS technology, and defined the encapsulation format of the RPR grouping that contains the MPLS label, realize the Route Selection of correct RPR grouping to utilize tunnel label, realize the transannular function, guaranteed the whole network QoS end to end, gateway has the function of MPLS LSR, can with the MPLS network interworking, overcome the existing in prior technology shortcoming.
The present invention can also utilize the MPLS label to realize user's QoS management and SLA are ensured.
Major advantage of the present invention is:
1. do not need operator that external equipment, the management cost of having saved machine room space and equipment are installed;
2. be easy to dilatation.All Route Selection only are based on local information and do not need to know overall information;
3. operator provides two layers of transparent service;
4. can in network-wide basis, the different grades of service be set, realize QoS end to end different users;
5. adopt between two rings that binode is interconnected just can be expanded to the protection mechanism that the RPR ring provides in encircle more and realized the elastic return in the network-wide basis;
6.MPLS technology maturation is easy to application.
Description of drawings:
What Fig. 1 represented is a two-way RPR ring
What Fig. 2 represented is the example that a RPR gateway is connecting three RPR rings
What Fig. 3 represented is that three RPR rings are by two a kind of modes that the RPR gateway is interconnected
What Fig. 4 represented is the encapsulation format that contains the RPR grouping of MPLS label
What Fig. 5 represented is that two RPR rings are by two interconnected a kind of modes of gateway
Embodiment:
The invention will be further described below in conjunction with drawings and Examples.
In Fig. 3, three RPR rings have been realized interconnected by two RPR gateways.A lot of fringe nodes are all arranged on each ring, and fringe node is collected from user's message and is sent on the RPR ring, sends the user to from encircling the message that receives to this node user simultaneously, and the message of non-node need continue to transmit forward.Gateway connects a plurality of RPR rings, finishes the forwarding capability of many interannulars.
As shown in Figure 4, be a kind of encapsulation format of RPR grouping of the MPLS of containing label.Wherein, da is the point of destination MAC Address, sa is the source station MAC Address, tunnelLabel is initiate a kind of MPLS label, expression tunnel label, the MPLS tag format of use standard, the Label that contains a 20bit, the exp of 3bit and out of Memory, gateway utilize Label information to establish route, utilize exp information to realize the grade of service that they are different.
In Fig. 2, gateway G is connecting three RPR rings, ring A, ring B and ring C.Each fringe node all has a MAC Address, gateway also has a MAC Address, when fringe node Ea desire sends message to fringe node Eb, the MAC Address of only need the da territory in heading filling out fringe node Eb gets final product, this moment, the tunnelLabel territory was invalid, and this message is from Ea, during through other fringe node, these nodes can carry out the MAC Address coupling, find it is not the message of this node, can continue to transmit forward, if through gateway node, gateway node can carry out the MAC Address coupling equally, find non-node message, can continue before this hoop, to transmit, until node Eb, Eb finds the MAC Address coupling, then receives this message.When the Eb desire sends message to Ec, need transannular this moment, the MAC Address of at first filling out gateway in the da territory of heading gets final product, show that this message is a gateway in the destination of this ring, fill out gateway G in the tunnelLabel territory then and distribute to its tunnelLabel, after message triggers from Eb, the terminal point that at first can arrive this ring is gateway G, after gateway G receives this message, the discovery MAC Address is mated, and then passes through control plane according to the tunnelLabel basis, uses the method or the LDP of static configuration, agreements such as BGP are set up the label switched path information of the whole network, search local routing table, find that this message is the Ec node of whereabouts ring C,, so the da territory of message is replaced to the MAC Address of Ec, be sent to ring C, enter the final destination node Ec that arrives behind the ring C.Gateway G can realize according to the entrained class of service information in exp territory among the tunnelLabel user's QoS management and SLA are ensured when heavy traffic.
For another example, fringe node Ea among Fig. 3 desires when Ec sends message, equally, at first fill out the MAC Address of gateway Ga and the tunnelLabel that Ga distributes to it, after message arrives Ga, Ga can know that according to local information the final destination of message is not in the ring that directly links to each other with it, so the da of heading is replaced to the MAC Address of next gateway Gb according to routing iinformation, simultaneously tunnelLabel is replaced to gateway Gb and distribute to its tunnelLabel, like this when message arrives gateway Gb, gateway Gb replaces to da the MAC Address of Ec again, because destination node is in the ring that directly links to each other with it, so the tunnelLabel territory of this moment is no longer valid, need not to replace, message can finally arrive destination node Ec.
Fig. 5 is one and utilizes the interconnected example that realizes the whole network protection of binode.If gateway Ga lost efficacy, perhaps some link occurs fault that link to each other with gateway Ga, so, gateway Gb can continuation be sent to other ring with Packet Service under the constant situation of QoS and SLA.