CN101515832A - Method and device for generating multipath system clock - Google Patents
Method and device for generating multipath system clock Download PDFInfo
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- CN101515832A CN101515832A CNA2008100079342A CN200810007934A CN101515832A CN 101515832 A CN101515832 A CN 101515832A CN A2008100079342 A CNA2008100079342 A CN A2008100079342A CN 200810007934 A CN200810007934 A CN 200810007934A CN 101515832 A CN101515832 A CN 101515832A
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Abstract
The invention discloses a method and a device for generating multipath system clocks, which belong to the field of communication. The method comprises the following steps: acquiring multipath reference clocks; tracking the obtained multipath reference clocks so as to generate the multipath system clocks, wherein the number of the multipath system clocks is less than or equal to that of the multipath reference clocks; and distributing the multipath system clocks according to a preset rule. The device comprises a reference clock acquiring module, a system clock generating module and a distributing module. The method and the device can achieve that a same network communication device works at different clock domains (different service plates work in the different clock domains or different terminals of a same service plate work in the different clock domains); and because the network communication device can work under different clock areas, the cross clock domain network deployment can be achieved by only one same network communication device, the cost for operators and the management and maintenance expenditure are reduced, and the resources are saved.
Description
Technical field
The present invention relates to the communications field, particularly a kind of method and apparatus that produces multipath system clock.
Background technology
Network communication and transmission equipment in traditional optical-fiber network often is designed to have only the synchro system in a clock source, network communication and transmission equipment can by self line port or the reference clock that inserts of external clock interface in select a clock source as self, other veneers in the equipment all are synchronized with the selected reference clock that goes out.
Referring to Fig. 1, provide a kind of schematic diagram of network communication and transmission equipment.Comprise various veneers in the network communication and transmission equipment, as be used to finish the veneer (being commonly referred to business board) of service processing function; Be used to finish the veneer (being called professional cross board) of professional cross scheduling; Veneer (being called clock board) that provides reference clock to other veneers of telecommunication transmission equipment or the like is provided.Wherein, clock board can comprise: clock selects source module, clock generating module and clock distribution module; Clock selects source module to be used for selecting one tunnel reference clock as this equipment from the M road reference clock of bringing, and sends to the clock generating module; The clock generating module is used to receive clock select the road reference clock that source module sends after, this reference clock is followed the tracks of, thereby obtain the system clock (phase relation that the phase place of reference clock and system clock is maintained fixed) of this network communication and transmission equipment, and the system clock that obtains is sent to the clock distribution module; The system clock that the clock distribution module is used for receiving is issued to other veneers uniformly, and other veneers in this network communication and transmission equipment all are synchronized with this system clock.
The inventor finds that there is following shortcoming and defect in use in the network communication and transmission equipment that provides in the existing technology when realization is of the present invention:
A network communication and transmission equipment can only be formed the network of a clock zone, and can not carry out networking by cross clock domain.As: certain transit carrier provides network communication and transmission equipment to use for a plurality of Virtual network operator leases, because the system clock of Virtual network operator is all different each other, will need this transit carrier to provide a plurality of network communication and transmission equipment for its use according to the demand of the system clock separately of Virtual network operator this moment; Increase the management of transit carrier, the expense of maintenance, also caused the waste of resource to a certain extent.
Summary of the invention
In order to make a network communication and transmission equipment can support multiple clock zone, the embodiment of the invention provides a kind of method and apparatus that produces multipath system clock.Described technical scheme is as follows:
A kind of method that produces multipath system clock, described method comprises:
Obtain the multichannel reference clock; The multichannel reference clock that obtains is followed the tracks of, produced multipath system clock, wherein, the quantity of described multipath system clock is smaller or equal to the quantity of described multichannel reference clock; Issue described multipath system clock according to preset rules.
A kind of equipment that produces multipath system clock, described equipment comprises:
The reference clock acquisition module is used to obtain the multichannel reference clock;
The system clock generation module is used to follow the tracks of the multichannel reference clock that described reference clock acquisition module gets access to, and produces multipath system clock;
Issue module, be used for issuing the system clock that described system clock generation module produces according to preset rules.
The beneficial effect of the technical scheme that the embodiment of the invention provides is:
The embodiment of the invention is by producing multipath system clock by same network communication equipment, according to preset rule the multipath system clock that produces is issued then, thereby can realize that same network communication equipment is operated in different clock zone (the different line ports that different business boards is operated in different clock zones or same business board are operated in different clock zones), only need to utilize same network communication equipment just can realize the cross clock domain networking this moment, reduced the cost of operator, and management, the expense of safeguarding has been saved the waste to resource.
Description of drawings
Fig. 1 is the schematic diagram that the network communication and transmission equipment that provides of prior art produces system clock;
Fig. 2 is the method flow diagram of the generation multichannel reference clock that provides of the embodiment of the invention 1;
Fig. 3 is the schematic diagram that network communication and transmission equipment that the embodiment of the invention 1 provides issues multipath system clock;
Fig. 4 is the schematic diagram of the generation multipath system clock that provides of the embodiment of the invention 1;
Fig. 5 is the equipment schematic diagram of the generation multipath system clock that provides of the embodiment of the invention 2
Fig. 6 is that the network level of the equipment that provides of the embodiment of the invention 2 is used schematic diagram;
Fig. 7 is that another network level of the equipment that provides of the embodiment of the invention 2 is used schematic diagram;
Fig. 8 is that the 3rd network level of the equipment that provides of the embodiment of the invention 2 is used schematic diagram;
Fig. 9 is that the 4th network level of the equipment that provides of the embodiment of the invention 2 is used schematic diagram.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, embodiment of the present invention is described further in detail below in conjunction with accompanying drawing.
Embodiment of the present invention is by producing multipath system clock by same network communication equipment, according to preset rule the multipath system clock that produces is issued then, thereby the different business board of same network communication equipment is operated under the different clock zones, or the different line ports of same business board are operated under the different clock zones.When network application, whether the transmission network in the middle of can not relying on is supported under the prerequisite that the business of a plurality of clock zones transmits a plurality of system clock corresponding service are successfully transmitted in transmission network; Can also realize forming the transmission network of different clock-domains by same network communication equipment; And realize in the same network communication equipment the multiple clock of coexistence, as TOP (Timing Over Packet, synchronised clock/the SDH of the synchronised clock message clock)/1588 (Synchronous Digital Hierarchy, synchronised clock/BITS (Building Integrated Timing System of synchronised clock synchronous digital hierarchy)/synchronous ether, Building Integrated Timing Supply) synchronised clock or the like, wherein, method is as follows: obtain the multichannel reference clock; The multichannel reference clock that obtains is followed the tracks of, produced multipath system clock, wherein, the quantity of multipath system clock is smaller or equal to the quantity of multichannel reference clock; Issue multipath system clock according to preset rules.
Embodiment 1
Referring to Fig. 2, the embodiment of the invention provides a kind of method that produces multipath system clock, and particular content is as follows:
101: the clock source of network communication and transmission equipment is from the M road reference clock that line port and/or external clock interface by equipment recover to obtain, select N road reference clock, thereby this N road reference clock followed the tracks of obtaining N road system clock, with the N road system clock that obtains system clock as equipment self.
For example: the reference clock that recovers one road 8KHz in the service message that from the service message that receives of line port A, recover the reference clock of one road 8KHz, receives by line port B,, by the reference clock of a 8KHz of external clock interface recovery Wherein, the reference clock of each 8KHz that above-mentioned recovery obtains is from different Virtual network operators, so though be all 8KHz, still be under the jurisdiction of different clock zones.Therefrom select 3 road reference clocks and follow the tracks of, obtain three road system clocks, and three road system clocks that will obtain are as the system clock of equipment self, as the 8KHz reference clock that recovers by line port A is followed the tracks of the first via system clock that obtains 38MHz; The 8KHz reference clock that recovers by line port B is followed the tracks of the second road system clock that obtains 38MHz; To recovering to obtain the Third Road system clock that the 8KHz reference clock recovers to obtain 38MHz by the external clock interface.At this moment, first via system clock, the second road system clock and Third Road system clock have correspondingly constituted three different clock zones.The embodiment of the invention does not limit means and the mode of obtaining reference clock.
102:,, be distributed in the network communication and transmission equipment in other veneers of managing business (being business board) or be distributed on the different line ports of same business board according to preset rule with the N road system clock that obtains.
With reference to figure 3, the schematic diagram of the network communication and transmission equipment dissemination system clock that provides for the embodiment of the invention.As shown in the figure, clock board as the clock source of network communication and transmission equipment is selected N road reference clock from the M road reference clock of sending here, wherein M road reference clock can from introduce by the external clock interface, can be by from the physical layer code stream that extracts the business board line port, also can obtain from the clock message information of peeling off by the TOP technology in the message that the business board line port receives.N road reference clock is followed the tracks of the N road system clock that obtains, according to preset rule the N road system clock that obtains is issued by selector, wherein, preset rule can for N road system clock is issued in the different business boards (be used to offer this professional physical layer code stream encapsulation is used or this business board downstream equipment provide messages containing clock information to use), also can be for (being used to make same business board can be operated under the different clock zones) on the different line ports that N road system clock are issued to same business board.Wherein, M, N be greater than 0 integer and, M is not less than N.
Referring to Fig. 4, the mode of obtaining reference clock is that example describes with the form of the TOP message that obtains by the TOP technology, as shown in the figure, comprise in the ordinary business practice plate: Business Processing chip, TOP message extraction/insertion chip, PLL (Phase LockedLoop, phase-locked loop) etc.; Comprise in the clock board: the TOP message converges/distributes chip, TOP message process chip, clock distribution chip etc.
S1: business board A receives message by line port, sends into the Business Processing chip and handles, and this message carries professional clock information.
S2:TOP message extraction/insertion chip extracts the TOP message that carries clock information from professional process chip.
S3:TOP message extraction/insertion chip converges/distributes chip with the TOP message that the TOP message that extracts sends to clock board, and wherein, this TOP message can converge/distribute the transmission of chip FE bus by connecting TOP message extraction/insertion chip and TOP message.
In like manner, the TOP message of clock board converges/distribute chip can obtain multichannel TOP message from the different business plate, and the different TOP message correspondence of multichannel different clock zones usually.Present embodiment converges/distribute chip with the TOP message, and to get access to M road TOP message be that example describes.
The S4:TOP message converges/distributes chip and selects N road TOP message send to TOP message process chip from the TOP message of M road.
S5:TOP message process chip is recovered the N road TOP message that receives, and obtains N road reference clock, thereby and this N road reference clock followed the tracks of to produce obtains N road system clock.
S6: the N road system clock that obtains is distributed according to this equipment preset rule.As preset rule for multipath system clock being issued to each business board or multipath system clock being issued on the different line port of same business board.
Wherein, the N road system clock that obtains is distributed according to this equipment preset rule, present embodiment is that example describes to converge/to distribute chip and clock distribution chip sending system clock by the TOP message:
For example:
1) converges/distribute chip by the TOP message and issue N road system clock, be used to provide to business board in this network communication equipment and use, this business board uses the system clock that receives to be used for providing the TOP that carries clock information message to its upstream device, and is specific as follows:
The S7a:TOP message converges/distributes chip and receives N road system clock, carry out the selection of system clock and slotting down as required: riches all the way delivers to business board B as selecting from the system clock of N road, is used for the TOP clock that carries as the TOP message that this business board B provides;
S8a: the TOP message extraction/insertion chip among the business board B sends to the Business Processing chip with this TOP message after the TOP clock that gets access to is packaged into the TOP message, and the Business Processing chip offers the upstream device use with TOP message and service message.
2) issue N road system clock by clock distribution chip, clock distribution chip is used for selecting that riches all the way and giving from multipath system clock the PLL etc. of certain business board, uses as the system clock of this business board; Or therefrom select a few roads to send to the different line port of same business board, different line ports is operated under the different clock zones.Specific as follows:
S7b: clock distribution chip will receive N road system clock, select one tunnel (as the N road) and send to the system clock of the PLL of business board B, select PLL that one tunnel (as the first via) send to business board A as this himself system clock as this business board self; Or select the 1 road and the 2 tunnel line port 1 and the line port 2 that sends to business board C respectively, make the different line ports of business board C be operated in (not shown) under the different clock zones.
Business board A can provide the TOP that carries clock information message to clock board among Fig. 4, and the TOP message that is provided by clock board in like manner also can be provided; The TOP message that is provided by clock board is provided business board B, in like manner also can provide the TOP that carries clock information message to clock board.
It is the explanation that example is carried out that present embodiment obtains reference clock with TOP, other dissimilar clock, and as the synchronised clock of SDH, the synchronised clock of synchronous ether, 1588 synchronised clock, the synchronised clock of BITS, method is similar, repeats no more.
The method that the embodiment of the invention provides is by producing multipath system clock, according to preset rule the multipath system clock that produces is issued then, can realize same network communication equipment support multipath system clock, and multipath system clock can be dissimilar clock, can also realize that the business board on the same network communication equipment can be operated in different clock-domains, can organize the network of different clock-domains; In the time of can also realizing carrying the message transmission of clock information, multipath system clock can transmit in same transmission network simultaneously, in the end-to-end recovery of carrying out multipath system clock of transmission network.
Embodiment 2
Referring to Fig. 5, the embodiment of the invention provides a kind of equipment that produces multipath system clock, and equipment comprises:
The reference clock acquisition module is used to obtain the multichannel reference clock;
The system clock generation module is used for the multichannel reference clock that track reference clock acquisition module gets access to, and produces multipath system clock;
Issue module, be used for the system clock that produces according to preset rules sending system clock generating module.
Wherein, the reference clock acquisition module is specially:
First acquiring unit is used for recovering to obtain the multichannel reference clock by the physical layer recovery and/or the service message of line port.
Wherein, the reference clock acquisition module is specially:
Second acquisition unit is used for obtaining the multichannel reference clock by the external clock interface.
Wherein, issuing module is specially:
Issue the unit, be used for corresponding relation, issue multipath system clock to the different line ports of different business boards and/or same business board according to system clock and clock zone;
Wherein, the equipment of the generation multipath system clock that provides of the embodiment of the invention also comprises:
Rule is provided with module, is used to be provided with the rule that issues multipath system clock.
The equipment that the embodiment of the invention provides can produce multipath system clock, thereby realizes just can supporting multipath system clock by an equipment, and multipath system clock can be dissimilar clock; The equipment that utilizes present embodiment to provide can be formed the network of different clock-domains; The equipment that utilizes present embodiment to provide can also realize that multipath system clock transmits simultaneously in same transmission network.
Referring to Fig. 6, the technical scheme of utilizing the embodiment of the invention to provide, whether network communication equipment A can make different system clock corresponding service transmit in same transmission network, do not rely on this transmission network and support the business of a plurality of system clocks to transmit.
Referring to Fig. 7, the technical scheme of utilizing the embodiment of the invention to provide, a network communication equipment can be formed the transmission network of different clock-domains, the line ports different with network communication equipment B as network communication equipment A are operated in different clock zones, so can form the transmission network of first clock zone, the transmission network of a N clock zone.
Referring to Fig. 8, the technical scheme of utilizing the embodiment of the invention to provide, a network communication equipment can be supported the coexistence of multiple systems clock, thereby supports different transmission networks to use respectively; As the STM-N that supports to coexist (Synchronous Transfer Mode, synchronous transfer mode) clock zone clock and ether clock zone clock synchronously, this STM-N clock zone clock is supported STM/WDM (Wavelength Division Multiplexing, wavelength division multiplexing) transmission network; Ether clock zone clock is supported IP (Internet Protocol, procotol)/MPLS (Multi-Protocol Label Switching, multiprotocol label switching) transmission network synchronously.
Referring to Fig. 9, the technical scheme of utilizing the embodiment of the invention to provide, can solve in the business that transmits simultaneously on the same equipment in the operation of many families, the clock synchronization of different operators can be asynchronous, for example: in wireless transmission solution, the RNC of different operators (Radio Network Controller, radio network controller) may be asynchronous, but the RNC of same operator and NodeB need synchronously, suppose that three tame operators are operated under the different system clock territories, because thereby network communication equipment X can support the business in the operation of the many families of multipath system clock carrying, so, only need to use a network communication equipment X, just can provide service for three tame operators, thereby the radio network controller of realization first hand operator and the NodeB's of himself is synchronous, and the radio network controller of the second tame operator and the NodeB's of himself is synchronous, and the radio network controller of the 3rd tame operator and the NodeB's of himself is synchronous.
Part steps in the embodiment of the invention can utilize software to realize that corresponding software programs can be stored in the storage medium that can read, as CD or hard disk etc.
Below only be specific embodiments of the invention;, for those skilled in the art, not all under the prerequisite that does not break away from the principle of the invention in order to restriction the present invention; any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. a method that produces multipath system clock is characterized in that, described method comprises:
Obtain the multichannel reference clock;
The multichannel reference clock that obtains is followed the tracks of, produced multipath system clock, wherein, the quantity of described multipath system clock is smaller or equal to the quantity of described multichannel reference clock;
Issue described multipath system clock according to preset rules.
2. the method for generation multipath system clock as claimed in claim 1 is characterized in that, the described multichannel reference clock that obtains is specially:
Physical layer recovery and/or service message by line port recover to obtain the multichannel reference clock.
3. the method for generation multipath system clock as claimed in claim 1 is characterized in that, the described multichannel reference clock that obtains is specially:
Obtain the multichannel reference clock by the external clock interface.
4. the method for generation multipath system clock as claimed in claim 1 is characterized in that, describedly issues described multipath system clock according to preset rules, is specially:
According to the corresponding relation of described system clock and clock zone, issue described multipath system clock to different business boards.
5. the method for generation multipath system clock as claimed in claim 1 is characterized in that, describedly issues described multipath system clock according to preset rules, is specially:
According to the corresponding relation of described system clock and clock zone, issue described multipath system clock to the different line ports of same business board.
6. an equipment that produces multipath system clock is characterized in that, described equipment comprises:
The reference clock acquisition module is used to obtain the multichannel reference clock;
The system clock generation module is used to follow the tracks of the multichannel reference clock that described reference clock acquisition module gets access to, and produces multipath system clock;
Issue module, be used for issuing the system clock that described system clock generation module produces according to preset rules.
7. the equipment of generation multipath system clock as claimed in claim 6 is characterized in that, described reference clock acquisition module is specially:
First acquiring unit is used for recovering to obtain the multichannel reference clock by the physical layer recovery and/or the service message of line port.
8. the equipment of generation multipath system clock as claimed in claim 6 is characterized in that, the described module that issues is specially:
Issue the unit, be used for corresponding relation, issue described multipath system clock to the different line ports of different business boards and/or same business board according to described system clock and clock zone;
9. the equipment of generation multipath system clock as claimed in claim 6 is characterized in that, described equipment also comprises:
Rule is provided with module, is used to be provided with the rule that issues described multipath system clock.
10. the equipment of generation multipath system clock as claimed in claim 6 is characterized in that, described reference clock acquisition module is specially:
Second acquisition unit is used for obtaining the multichannel reference clock by the external clock interface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2008100079342A CN101515832A (en) | 2008-02-20 | 2008-02-20 | Method and device for generating multipath system clock |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2008100079342A CN101515832A (en) | 2008-02-20 | 2008-02-20 | Method and device for generating multipath system clock |
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| CN101515832A true CN101515832A (en) | 2009-08-26 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNA2008100079342A Pending CN101515832A (en) | 2008-02-20 | 2008-02-20 | Method and device for generating multipath system clock |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102263629A (en) * | 2010-05-24 | 2011-11-30 | 华为技术有限公司 | Method for time synchronization among boards, clock board and NE (network element) device |
| CN103959688A (en) * | 2013-12-24 | 2014-07-30 | 华为技术有限公司 | Multiple clock domain clock synchronization method, wire card and Ethernet equipment |
| CN104185267A (en) * | 2013-05-27 | 2014-12-03 | 联想(北京)有限公司 | Method and apparatus for determining frequency of reference clock of electronic equipment |
| CN111106889A (en) * | 2018-10-25 | 2020-05-05 | 华为技术有限公司 | Clock synchronization method and device |
| CN113721703A (en) * | 2021-08-19 | 2021-11-30 | 飞腾信息技术有限公司 | Clock synchronization control device, system and control method in multi-channel CPU system |
| CN113852438A (en) * | 2021-09-22 | 2021-12-28 | 新华三信息安全技术有限公司 | Clock buckle plate, distributed system and clock synchronization method of distributed system |
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2008
- 2008-02-20 CN CNA2008100079342A patent/CN101515832A/en active Pending
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102263629A (en) * | 2010-05-24 | 2011-11-30 | 华为技术有限公司 | Method for time synchronization among boards, clock board and NE (network element) device |
| CN102263629B (en) * | 2010-05-24 | 2013-11-06 | 华为技术有限公司 | Method for time synchronization among boards, clock board and NE (network element) device |
| CN104185267B (en) * | 2013-05-27 | 2019-03-08 | 联想(北京)有限公司 | Method and apparatus for determining the frequency of the reference clock of electronic equipment |
| CN104185267A (en) * | 2013-05-27 | 2014-12-03 | 联想(北京)有限公司 | Method and apparatus for determining frequency of reference clock of electronic equipment |
| WO2015096041A1 (en) * | 2013-12-24 | 2015-07-02 | 华为技术有限公司 | Clock synchronization method for multiple clock domains, line card, and ethernet device |
| CN103959688B (en) * | 2013-12-24 | 2018-03-02 | 华为技术有限公司 | A kind of clock synchronizing method of multi-clock zone, line card and ethernet device |
| CN103959688A (en) * | 2013-12-24 | 2014-07-30 | 华为技术有限公司 | Multiple clock domain clock synchronization method, wire card and Ethernet equipment |
| CN111106889A (en) * | 2018-10-25 | 2020-05-05 | 华为技术有限公司 | Clock synchronization method and device |
| CN111106889B (en) * | 2018-10-25 | 2021-04-20 | 华为技术有限公司 | Clock synchronization method and device |
| US11451316B2 (en) | 2018-10-25 | 2022-09-20 | Huawei Technologies Co., Ltd. | Clock synchronization method and apparatus |
| CN113721703A (en) * | 2021-08-19 | 2021-11-30 | 飞腾信息技术有限公司 | Clock synchronization control device, system and control method in multi-channel CPU system |
| CN113721703B (en) * | 2021-08-19 | 2024-02-13 | 飞腾信息技术有限公司 | Clock synchronization control device, system and control method in multi-path CPU system |
| CN113852438A (en) * | 2021-09-22 | 2021-12-28 | 新华三信息安全技术有限公司 | Clock buckle plate, distributed system and clock synchronization method of distributed system |
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Application publication date: 20090826 |