CN102801638B - A kind of management of port repeat state of exchange chip and control method - Google Patents
A kind of management of port repeat state of exchange chip and control method Download PDFInfo
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Abstract
The present invention relates to a kind of management and control method of port repeat state of exchange chip, comprise the following steps: step 1, create Instance; An adaptation layer STG is provided in the middle of upper-layer protocol and bottom STG? Share, described STG? Share safeguards a protocol instance VLAN mapping table, this mapping table is called example table Instance, example table Instance and upper-layer protocol example one_to_one corresponding, step 2, repartitions example table Instance according to set operation rule, the table occured simultaneously that do not have marked off is called sub-instance table Sub, step 3, produces bottom STG table according to Sub, Sub and bottom STG one_to_one corresponding.Does method of the present invention, provide an adaptation layer STG in the middle of upper-layer protocol and bottom STG? Share, is mapped the subset repartitioned out and do not have to occur simultaneously, is arranged the STG of exchange chip by these subsets to the VLAN of upper strata example; Further, a kind of algorithm calculating Multi-instance subset is fast and effectively proposed.
Description
Technical field
The present invention relates to management and the control of exchange chip, is a kind of management and control method of port repeat state of exchange chip specifically.
Background technology
Existing switch generally eliminates the loop of double layer network by Spanning-Tree Protocol, looped network agreement etc., calculate or the role of configured port according to agreement, select one or more port, the forwarding state of port is set by exchange chip to reach the object controlling traffic forwarding.Usually, exchange chip provides STG(spanning tree group, SpanningTreeGroup) forwarding state of port is set, STG is for identifying VLAN(VLAN, VirtualLocalAreaNetwork) the spanning tree group belonging to, record the state that each port is residing in each VLAN group, control port forwards and blocks in certain VLAN group.
The example of corresponding agreement, when processing Spanning-Tree Protocol, looped network agreement, often maps directly on STG by industry, and this does not have problem when processing single agreement.But, when multiple agreement is applied simultaneously, and the VLAN group that protocol instance maps is identical and when having overlap, how appropriate for VLAN group is mapped on STG, exchange chip manufacturer does not provide clear and definite solution, is then evaded the question, as based on Multiple Spanning Tree Instance by restriction application scenarios in the industry, other protocol instances must be corresponding with Multiple Spanning Tree Instance, otherwise do not allow configuration.Which has limited the application of exchange chip STG.
Summary of the invention
For the defect existed in prior art, the object of the present invention is to provide a kind of management and control method of port repeat state of exchange chip, an adaptation layer STGShare is provided in the middle of upper-layer protocol and bottom STG, the VLAN of upper strata example is mapped to the subset repartitioned out and do not have to occur simultaneously, the STG of exchange chip is set by these subsets; Further, a kind of algorithm calculating Multi-instance subset is fast and effectively proposed.
For reaching above object, the technical scheme that the present invention takes is:
The management of the port repeat state of exchange chip and a control method, is characterized in that, comprise the following steps:
Step 1, creates example table Instance; An adaptation layer STGShare is provided in the middle of upper-layer protocol and bottom STG, described STGShare safeguards a protocol instance VLAN mapping table, this protocol instance VLAN mapping table is called example table Instance, example table Instance and upper-layer protocol example one_to_one corresponding
Step 2, is all considered as set, then repartitions example table Instance according to set operation rule by each example table Instance, obtain some subsets not having to occur simultaneously, the subset of each common factor does not have the table of common factor as one, the table occured simultaneously that do not have marked off is called sub-instance table Sub
For the ease of the calculating of set, here a concept unit table Meta is introduced, the corresponding Meta of each VLAN, Meta is indivisible, Instance and Sub is the set of Meta, the difference of Instance and Sub is that between Instance, Meta can be overlapping, and between Sub, Meta can not be overlapping
Step 3, produces bottom STG table according to sub-instance table Sub, sub-instance table Sub and bottom STG one_to_one corresponding.
On the basis of technique scheme, when only protocols having example A and protocol instance B two protocol instances, mark off 3 sub-example table Sub:Sub1:A-A ∩ B, Sub2:A ∩ B, Sub3:B-A ∩ B according to set operation rule STGShare, and generate corresponding STG table according to sub-instance table Sub: STG1, STG2, STG3;
When multiple protocol instance exists, mark off the subset not having to occur simultaneously equally according to set operation rule, and generate STG one to one;
The number of STG is equal with the nonvoid subset number not having to occur simultaneously produced according to set operation rule.
On the basis of technique scheme, when A-A ∩ B, A ∩ B, B-A ∩ B are not empty, produce 3 STG tables; As A ∩ B=A or A ∩ B=B and A ≠ B time, produce 2 STG table; When a=b, 1 STG table is only produced.
On the basis of technique scheme, when example VLAN maps change, need the STG table carrying out recalculating whole bottom,
Described example VLAN maps change and at least comprises: the mapping certain example being carried out to an increase VLAN or group VLAN, certain example is carried out to the mapping of a deletion VLAN or group VLAN.
On the basis of technique scheme, step 2 adopts following algorithm to repartition fast and effectively example table Instance, marks off multiple sub-instance table Sub not having to occur simultaneously:
Step 1: obtain the Instance created;
Step 2: under initial condition, the VLAN that Instance maps, as newly-increased VLAN process, performs step 3, when revising the VLAN that Instance maps, be divided into increase VLAN mapping and delete VLAN and map two large classes, increase VLAN maps execution step 3, deletes VLAN and maps execution step 4;
Step 3:Instance increases VLAN and maps, and no matter is individual vlan or one group of VLAN, all creates the Meta of corresponding VLAN by individual vlan successively, and put 1 on the Meta position that Map is corresponding, performs step 5;
Step 4:Instance deletes VLAN and maps, and no matter is individual vlan or one group of VLAN, all creates the Meta of corresponding VLAN by individual vlan successively, and set to 0 on the Meta position that Map is corresponding, performs step 5;
Step 5: travel through all Meta, remove the mapping relations of Sub and Meta, namely delete Meta from Sub, delete Sub when Sub does not comprise any Meta, and oppositely find corresponding Instance by the Map of Sub, the corresponding Sub position of Map of putting corresponding Instance is 0; Again the mapping relations of Meta to Instance are associated, if Instance comprises Meta, then the corresponding Instance position 1 of the Map of Meta, otherwise set to 0, perform step 6;
Step 6: travel through all Meta and Sub, if the Map of Meta with Sub/Meta is identical, then Meta and Sub/Meta merges becomes new Sub, there is no the Sub that merged Meta also becomes new, and by merged fall the Map of Sub/Meta oppositely find corresponding Instance, the corresponding Sub/Meta position of Map of putting corresponding Instance is 0, according to the STG that Sub is updated to exchange chip, exits algorithm.
The management of the port repeat state of exchange chip of the present invention and control method, an adaptation layer STGShare is provided in the middle of upper-layer protocol and bottom STG, the VLAN of upper strata example is mapped to the subset repartitioned out and do not have to occur simultaneously, the STG of exchange chip is set by these subsets; Further, a kind of algorithm calculating Multi-instance subset is fast and effectively proposed.
The adaptation layer STGShare that the present invention provides not only solves two layers of port control protocols mixed networking problem, and extend the mapping relations of example, STG and port, the quantity of bottom exchange chip STG is limited, the Instance of STGShare is unlimited in theory, this VLAN forwarding state making upper-layer protocol directly arrange arbitrary port becomes possibility, has effectively expanded the application of exchange chip.
Accompanying drawing explanation
The present invention has following accompanying drawing:
After Fig. 1 introduces STGShare, upper-layer protocol example changes schematic diagram to the mapping of bottom STG,
Fig. 2 STGShare passes through set calculating and setting bottom STG schematic diagram,
The algorithm flow chart that Fig. 3 repartitions fast and effectively to example table Instance.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further detail.
Switch supports 4094 VLAN usually, for the dual consideration of inadequate resource and efficiency, exchange chip is not the arbitrary vlan spanning-tree state (disable directly arranging arbitrary port, listening, learning, forwarding, blocking), and be to provide a limited number of STG and show, STG is called spanning tree group, the size of quantity depends on grade and the ability of chip, generally 128/256/512 etc., a STG table is the mapping of one group of VLAN, a VLAN can only belong to a STG, arranging the forwarding state of port in certain VLAN is that port status by arranging STG belonging to VLAN realizes.
The present invention provides an adaptation layer in the middle of upper-layer protocol and bottom STG, be called STGShare, as shown in Figure 1, in Fig. 1, left side is traditional example/STG mapping method, protocol instance maps directly on bottom STG, and in Fig. 1, right side is the example/STG mapping method after introducing STGShare.
The management of the port repeat state of exchange chip of the present invention and control method, comprise the following steps:
Step 1, creates example table Instance; An adaptation layer STGShare is provided in the middle of upper-layer protocol and bottom STG, described STGShare safeguards a protocol instance VLAN mapping table, this protocol instance VLAN mapping table is called example table Instance, example table Instance and upper-layer protocol example one_to_one corresponding
Step 2, is all considered as set, then repartitions example table Instance according to set operation rule by each example table Instance, obtain some subsets not having to occur simultaneously, the subset of each common factor does not have the table of common factor as one, the table occured simultaneously that do not have marked off is called sub-instance table Sub
For the ease of the calculating of set, here a concept unit table Meta is introduced, the corresponding Meta of each VLAN, Meta is indivisible, Instance and Sub is the set of Meta, the difference of Instance and Sub is that between Instance, Meta can be overlapping, and between Sub, Meta can not be overlapping
Step 3, produces bottom STG table according to sub-instance table Sub, sub-instance table Sub and bottom STG one_to_one corresponding.
For protocol instance A and protocol instance B, 3 sub-example table Sub:Sub1:A-A ∩ B, Sub2:A ∩ B, Sub3:B-A ∩ B is marked off according to set operation rule STGShare, and generate corresponding STG table according to sub-instance table Sub: STG1, STG2, STG3, as shown in Figure 2.
The VLAN mapping table of protocol instance A and protocol instance B is by set operation, and the bottom STG marked off has situation in 3:
1, when A-A ∩ B, A ∩ B, B-A ∩ B are not empty, 3 STG tables are produced;
2, A ∩ B=A or A ∩ B=B and A ≠ B time, produce 2 STG table;
3, during A=B, 1 STG table is only produced.
According to set operation rule, any number of protocol instance can be solved and share STG table problem, when multiple protocol instance exists, the subset not having to occur simultaneously is marked off equally according to set operation rule, and the number generating STG, STG is one to one equal with the nonvoid subset number not having to occur simultaneously produced according to set operation rule, when the VLAN of protocol instance maps change, STGShare is repartitioned sub-instance table Sub by segmentation/merging, and is updated to bottom exchange chip.
When example VLAN maps change, mapping as the increase of certain example or a deletion VLAN or group VLAN (refers to the mapping certain example being carried out to an increase VLAN or group VLAN, certain example is carried out to the mapping of a deletion VLAN or group VLAN), the STG table of whole bottom all may change, and needs to recalculate.For the situation of two examples, be easy to dividing subset, but in practical application, usually have very Multi-instance and exist, the division of subset exponentially increases along with the increase of example, divides quite difficulty.The present invention then proposes one subset division algorithm fast and effectively, and this algorithm is used for calculating Multi-instance subset fast and effectively.
On the basis of technique scheme, as shown in Figure 3, step 2 adopts following algorithm to repartition fast and effectively example table Instance, marks off multiple sub-instance table Sub not having to occur simultaneously:
Step 1: obtain the Instance created;
Step 2: under initial condition, the VLAN that Instance maps, as newly-increased VLAN process, performs step 3, when revising the VLAN that Instance maps, be divided into increase VLAN mapping and delete VLAN and map two large classes, increase VLAN maps execution step 3, deletes VLAN and maps execution step 4;
Step 3:Instance increases VLAN and maps, and no matter is individual vlan or one group of VLAN, all creates the Meta of corresponding VLAN by individual vlan successively, and put 1 on the Meta position that Map is corresponding, performs step 5;
Step 4:Instance deletes VLAN and maps, and no matter is individual vlan or one group of VLAN, all creates the Meta of corresponding VLAN by individual vlan successively, and set to 0 on the Meta position that Map is corresponding, performs step 5;
Step 5: travel through all Meta, remove the mapping relations of Sub and Meta, namely delete Meta from Sub, delete Sub when Sub does not comprise any Meta, and oppositely find corresponding Instance by the Map of Sub, the corresponding Sub position of Map of putting corresponding Instance is 0; Again the mapping relations of Meta to Instance are associated, if Instance comprises Meta, then the corresponding Instance position 1 of the Map of Meta, otherwise set to 0, perform step 6;
Step 6: travel through all Meta and Sub, if the Map of Meta with Sub/Meta is identical, then Meta and Sub/Meta merges becomes new Sub, there is no the Sub that merged Meta also becomes new, and by merged fall the Map of Sub/Meta oppositely find corresponding Instance, the corresponding Sub/Meta position of Map of putting corresponding Instance is 0, according to the STG that Sub is updated to exchange chip, exits algorithm.
"/" is wherein the symbol of the supplement collection in set operation, namely calculates the set that in two set, non-common element set becomes.Whole algorithm is actually Rapid reversal and Remodeling.
Above-mentioned algorithm is when processing example Instance and increasing and/or delete VLAN mapping, and it is monolithic for splitting and/or merging the process performed, interrelated by Map between example Instance and Sub.When the changing in the forwarding state of a certain example Instance of port, by the Map of Instance, the Sub that each maps is set, is finally set to the STG of exchange chip.
Each Instance table has one to the mapping Map of Meta, when Instance table comprises certain Meta, then corresponding on mapping table Map position 1, otherwise set to 0, as example Instance1 maps VLAN1-3, Meta1 maps VLAN1, Meta2 and maps VLAN2, Meta3 and map VLAN3, then the upper 1-3 position 1 of the Map of Instance1, expression Instance1 and Meta1, Meta2 with Meta3 associate.Each Meta also has one to map Map, map its comprise by which example Instance, as Instance1 and Meta1, Meta2 with Meta3 associate, then Meta1, Meta2 and Meta3 the 1st of Map all puts 1.Meta can with VLAN one_to_one corresponding, namely Meta1 maps VLAN1 to Meta4094 and maps VLAN4094, but consider practical application and computational efficiency, Meta can be inconsistent with VLAN, creates as required, and Meta only appears in computational process, Meta is created by Instance, merge the Map information that Meta to Sub, Sub inherit Meta, be updated to the STG of exchange chip eventually through Sub.
The content be not described in detail in this specification belongs to the known prior art of professional and technical personnel in the field.
Claims (4)
1. the management of the port repeat state of exchange chip and a control method, is characterized in that, comprise the following steps:
Step 1, creates example table Instance; An adaptation layer STGShare is provided in the middle of upper-layer protocol and bottom STG, described STGShare safeguards a protocol instance VLAN mapping table, this protocol instance VLAN mapping table is called example table Instance, example table Instance and upper-layer protocol example one_to_one corresponding
Step 2, is all considered as set, then repartitions example table Instance according to set operation rule by each example table Instance, obtain some subsets not having to occur simultaneously, each subset not having to occur simultaneously does not have the table of common factor as one, the table occured simultaneously that do not have marked off is called sub-instance table Sub
For the ease of the calculating of set, here a concept unit table Meta is introduced, the corresponding Meta of each VLAN, Meta is indivisible, Instance and Sub is the set of Meta, the difference of Instance and Sub is that between Instance, Meta can be overlapping, and between Sub, Meta can not be overlapping
Each example table Instance has one to the mapping Map of Meta, when example table Instance comprises certain Meta, then in the Meta position 1 that Map is corresponding, otherwise set to 0, each Meta also have one map Map, map its comprise by which example table Instance
Step 3, produces bottom STG table according to sub-instance table Sub, sub-instance table Sub and bottom STG one_to_one corresponding,
Described step 2 adopts following algorithm to repartition fast and effectively example table Instance, marks off multiple sub-instance table Sub not having to occur simultaneously:
Step 21: obtain the Instance created;
Step 22: under initial condition, the VLAN that Instance maps is as newly-increased VLAN process, perform step 23, when revising the VLAN that Instance maps, be divided into increase VLAN mapping and delete VLAN and mapped two large classes, increase VLAN and map execution step 23, delete VLAN mapping and perform step 24;
Step 23:Instance increases VLAN and maps, and no matter is individual vlan or one group of VLAN, all creates the Meta of corresponding VLAN by individual vlan successively, and put 1 on the Meta position that Map is corresponding, performs step 25;
Step 24:Instance deletes VLAN and maps, and no matter is individual vlan or one group of VLAN, all creates the Meta of corresponding VLAN by individual vlan successively, and set to 0 on the Meta position that Map is corresponding, performs step 25;
Step 25: travel through all Meta, remove the mapping relations of Sub and Meta, namely delete Meta from Sub, delete Sub when Sub does not comprise any Meta, and oppositely find corresponding Instance by the Map of Sub, the corresponding Sub position of Map of putting corresponding Instance is 0; Again the mapping relations of Meta to Instance are associated, if Instance comprises Meta, then the corresponding Instance position 1 of the Map of Meta, otherwise set to 0, perform step 26;
Step 26: travel through all Meta and Sub, if Meta and C
subthe Map of Meta is identical, then Meta and C
submeta merge become new Sub, there is no the Sub that merged Meta also becomes new, and by merged fall C
subthe Map of Meta oppositely finds corresponding Instance, puts the corresponding C of Map of corresponding Instance
submeta position is 0, according to the STG that Sub is updated to exchange chip, exits algorithm;
Above-mentioned algorithm is when processing example table Instance and increasing and/or delete VLAN mapping, it is monolithic for removing and/or merging the process performed, interrelated by Map between example table Instance and Sub, when the forwarding state of a certain example table Instance changes, by the Map of example table Instance, the Sub that each maps is set, is updated to the STG of exchange chip eventually through Sub.
2. the management of the port repeat state of exchange chip as claimed in claim 1 and control method, it is characterized in that: when only protocols having example A and protocol instance B two protocol instances, mark off 3 sub-example table Sub:Sub1:A-A ∩ B, Sub2:A ∩ B, Sub3:B-A ∩ B according to set operation rule STGShare, and generate corresponding STG table according to sub-instance table Sub: STG1, STG2, STG3;
When multiple protocol instance exists, mark off the subset not having to occur simultaneously equally according to set operation rule, and generate STG one to one;
The number of STG is equal with the nonvoid subset number not having to occur simultaneously produced according to set operation rule.
3. the management of the port repeat state of exchange chip as claimed in claim 2 and control method, is characterized in that: when A-A ∩ B, A ∩ B, B-A ∩ B are for time empty, produce 3 STG and show; As A ∩ B=A or A ∩ B=B and A ≠ B time, produce 2 STG table; When a=b, 1 STG table is only produced.
4. the management of the port repeat state of exchange chip as claimed in claim 1 and control method, is characterized in that: when example VLAN maps change, need the STG table carrying out recalculating whole bottom,
Described example VLAN maps change and at least comprises: the mapping certain example being carried out to an increase VLAN or group VLAN, certain example is carried out to the mapping of a deletion VLAN or group VLAN.
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