CN103647615B - Delay jitter removing method and device in message transmission procedure - Google Patents
Delay jitter removing method and device in message transmission procedure Download PDFInfo
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Abstract
Delay jitter removing method and device in a kind of message transmission procedure that the embodiment of the present invention provides, the method comprises: object message is got before stamp, increase the length of the bit adjustment aim message of object message, so that the length of object message reaches preset length, object message is got to stamp getting stamp point, obtain the first time stamp of object message, detect the indication code that whether receives object message getting stamp point, if indication code do not detected, get the current count value of the first counter as target bit, every through a work period, the first counter deducts a bit number, bit number is the bit number of putting away from popping in the work period, according to target bit and described the first time stamp, obtain pop second time stamp at a place of current time. in the length of getting adjustment aim message before stamp point, by bit number waiting for transmission in counter measures protocol stack, realize the correction to delay jitter, can eliminate the delay jitter in transmission.
Description
Technical field
The present invention relates to the communication technology, relate in particular to delay jitter removing method in a kind of message transmission procedureAnd device.
Background technology
Accurate clock synchronization protocol (PreciseTimeProtocol is called for short PTP) is a kind of based on messageClock synchronization protocol, in order to realize Frequency Synchronization and the time synchronized between equipment and equipment. Fig. 1 isThe process of PIP message discrepancy protocol stack. As shown in Figure 1, in PTP agreement, PTP message is carried outGet time stamp, enter protocol stack and go out the moment point of protocol stack to record PTP message.
At current net environment, PTP message need to be carried in underlying protocol. Enter at PTP messageWhen protocol stack, need through underlying protocol processing to getting time stamp point from stacked, correspondingly, going outWhen protocol stack, also need through underlying protocol processing taking after time stamp. But in underlying protocol processingIn process, may, owing to processing that path is long, processing unit is more or the factor such as wide coupling, make PTPMessage is got time stamp point (IngressDelay) or is transferred to and pops from getting time stamp point being transferred to from stacked pointIn the process of point (EgressDelay), in propagation delay time, can there is larger delay jitter. These prolongLate shake is tens nanoseconds, at most tens or nanosecond up to a hundred at least, have a strong impact on the essence that clock time recoversDegree.
At present, the method for obtaining delay jitter data comprises: circuit analysis method and emulation advocate approach.
(1) circuit analysis method: after completing for the circuit design that realizes protocol stack, design engineer canTo analyze the formation of IngressDelay and EgressDelay, according to each component part, phone is divided intoMultiple unit, analyze the impact of each unit on whole delay jitter, to get message in transmitting procedureDelay jitter, then utilize this delay jitter to obtain the propagation delay time of message.
(2), after completing for the circuit design that realizes protocol stack, checking engineer constructs various excitation stripesPart, forms different simulation waveforms by various incentive condition exciting circuits, then analyzes various excitation stripesSimulation waveform under part, gets the delay jitter under various excitations, then utilizes delay jitter to obtain reportThe propagation delay time of literary composition.
Above-mentioned two kinds of methods that get delay jitter data, require the circuit must be simple, can not be to more multipleAssorted circuit is analyzed, and has limitation. And by above-mentioned two kinds of methods, the delay getting is trembledMoving accurate not, make to utilize the propagation delay time that delay jitter gets to have certain error.
Summary of the invention
The embodiment of the present invention provides delay jitter removing method and device in a kind of message transmission procedure, forEliminate message in the process of protocol stack transmission, the delay jitter of existence, to improve the synchronous precision of message.
Embodiment of the present invention first aspect provides delay jitter removing method in a kind of message transmission procedure,Comprise:
Object message is got before stamp, the bit that increases described object message is adjusted described target reportThe length of literary composition, so that the length of described object message reaches preset length;
Described object message is got to stamp getting stamp point, obtain the first time stamp of described object message;
Detect at the described stamp point of getting the indication code that whether receives described object message;
If described indication code do not detected, get the current count value of the first counter as target ratioSpecial number; Wherein, every through a work period, described the first counter deducts a bit number, instituteStating bit number is the bit number of putting away from popping in the described work period;
According to described target bit and described the first time stamp, get a described current time place of poppingThe second time stamp.
Embodiment of the present invention second aspect provides delay jitter cancellation element in a kind of message transmission procedure,Comprise:
Pretreatment module, for object message is got before stamp, increases the bit of described object messageThe length of described object message is adjusted in position, so that the length of described object message reaches preset length;
Get stamp module, for described object message being got to stamp getting stamp point, obtain described object messageThe first time stamp;
First detection module, for detecting at the described stamp point of getting the instruction that whether receives described object messageCode;
The first counting module, for the transmitting procedure in described object message, enters described object messageRow counting; Wherein, every through a work period, described the first counting module deducts a bit number,Described bit number is the bit number of putting away from popping in the described work period;
Acquisition module, if for described indication code not detected, gets described the first counting moduleCurrent count value is as target bit;
Computing module, for according to described target bit and described the first time stamp, gets described currentPop second time stamp at a place of moment.
The embodiment of the present invention provides delay jitter removing method and device in a kind of message transmission procedure,Object message is got before stamp, increase the length of the bit adjustment aim message of object message, withMake the length of object message reach preset length, described object message is got to stamp getting stamp point, obtainThe first time stamp of described object message, detects at the described stamp point of getting the finger that whether receives described object messageShow code, if described indication code do not detected, get the current count value of the first counter as targetBit number, wherein, every through a work period, described the first counter deducts a bit number,Described bit number is the bit number of putting away from popping in the described work period, according to described target bitsNumber and described the first time stamp, get pop second time stamp at a place of described current time. The present embodiment existsBefore getting stamp point, the length adjustment of object message is arrived to default length, by the first counter in real timeMeasure actual bit number waiting for transmission in protocol stack, realized the correction to delay jitter, can eliminate reportThe delay jitter of literary composition in transmitting procedure, improves the accuracy rate of propagation delay time, has improved the precision of message.
Brief description of the drawings
Fig. 1 is the schematic diagram of PTP message discrepancy protocol stack;
In a kind of message transmission procedure that Fig. 2 provides for the embodiment of the present invention, delay jitter removing method showsIntention;
Delay jitter removing method in the another kind of message transmission procedure that Fig. 3 provides for the embodiment of the present inventionSchematic diagram;
The knot of delay jitter cancellation element in a kind of message transmission procedure that Fig. 4 provides for the embodiment of the present inventionStructure schematic diagram;
Delay jitter cancellation element in the another kind of message transmission procedure that Fig. 5 provides for the embodiment of the present inventionStructural representation;
Fig. 6 shows for the structure of a kind of Ethernet 100GBASE-R bogey that the embodiment of the present invention providesIntention.
Detailed description of the invention
Below by drawings and Examples, technical scheme of the present invention is described in further detail.
Existing bogey is being got after time stamp object message, and object message is in the carrying of bogeyUnder be transferred to popping a little of protocol stack from getting stamp point, from getting stamp point to the transmitting procedure of popping a little, nowThere is bogey to comprise the multiple processing modules according to protocol generation, can process object message, asFrame sequence verification is calculated (FrameCheckSequenceCalculate is called for short FCSCalculate), is compiledCode, scrambling etc. After above-mentioned processing, often increase in the length of getting object message after stamp point. ByGetting stamp point in the length of object message and constantly changing to the length between popping a little, cannot be in real timeTracking target message is from getting stamp point to the propagation delay time of popping a little.
In the message transmission procedure that following embodiment provides, the executive agent of delay jitter removing method is agreementThe bogey of stack. Be transferred to process that protocol stack pops a little as example, explanation taking object message from getting stamp pointThe process that in the message transmission procedure that following embodiment provides, delay jitter is eliminated. As, bogey canFor Ethernet 40/100GBASE-R bogey.
In a kind of message transmission procedure that Fig. 2 provides for the embodiment of the present invention, delay jitter removing method showsIntention. As shown in Figure 2, the method comprises the following steps:
101,, object message is got before stamp, the bit that increases described object message is adjusted described orderThe length of mark message, so that the length of described object message reaches preset length.
For the length that ensures object message is to get stamp point constant or can be pre-to the length between popping a littlePhase, so that carry out real-time tracking to the propagation delay time of object message. In the present embodiment to object messageGet before stamp, bogey carries out pretreatment to object message, in object message, increases bit,So that the length of object message reaches default length.
Particularly, if 1 passage (LANE) transmission objectives message is only set on bogey, forAvoid sending and changing in the length of getting object message after stamp, bogey can increase default for object messageThe dummy bit position of length, this preset length can arrange flexibly according to the actual demand of protocol stack. LiftExample explanation, in prior art in the time that object message is transmitted on this LANE of setting, bogey pairObject message carries out, after checking treatment, obtaining the check results of this object message, and check results is addedIn object message, cause the length of object message to increase the bit identical with check results length, thisJust there is variation in the length that sample is got the rear object message of stamp point. In the present embodiment, due in object messageBefore getting stamp point, bogey carries out pretreatment to object message, and bogey can be target in advanceMessage increase length-specific for writing the dummy bit of above-mentioned check results. From getting stamp point to popping a littleIn the process of transmission objectives message, bogey will carry out the check results after checking treatment to object message,Write in advance in the dummy bit of the length-specific increasing, thereby make to get object message length after stamp pointConstant. It will be recognized by those skilled in the art that dissimilar object message and the difference of check results,The length of reserved dummy bit position can be different, and the length of dummy bit can be entered according to actual needsRow arranges flexibly.
If at least 2 LANE transmission objectives messages are set on bogey. Wherein, every LANEAn object message of upper transmission, the object message of every upper transmission of LANE is different. Should in realityWith in, for the object message popping and locating to align and transmit on every LANE, bogey is everyThe object message of the upper transmission of LANE is added an alignment identification (AlignmentMarker is called for short AM).Wherein, AM is for locating the object message of aliging popping. Many LANE synchronous transfer object message situationUnder, bogey, in the time sending object message, after the AM of alignment object message, then passes object messageBe passed to and pop a little. Receive after object message at a place of popping, bogey is by upper each LANE transmissionObject message between transmission crooked (Skew) shift out, by the AM of each object message of aliging,The object message of aliging.
In the present embodiment, for fear of sending variation, bogey in the length of getting object message after stamp pointFor the object message of the upper transmission of every LANE, in object message, insert in advance an AM, Yi JiweiObject message is reserved the dummy bit position of length-specific, carrys out the length of adjustment aim message, makes target reportThe length of literary composition reaches default length. Wherein, stabbing point to a process for transmission objectives message of popping from gettingIn, bogey can write bogey in reserved dummy bit to carry out after verification object messageCheck results.
Illustrate, in the time that object message is 1588 message, 1588 messages are at Ethernet 100GBASE-ROn bogey, transmit. Wherein, on 100GBASE-R bogey, be provided with 20 LANE, every1588 messages on LANE, are transmitted. In the present embodiment, 100GBAES-R bogey in advanceFor going up 1588 messages that transmit, every LANE increases the dummy bit position of 96 bits. 100GBAES-RBogey writes an AM in 64 reserved dummy bits. Stabbing point to a transmission of popping from gettingIn the process of 1588 messages, 100GBASE-R bogey carries out FCSCalculate to 1588 messagesProcess, obtain the check results of 32. 100GBASE-R writes surplus by the check results of 3232 remaining dummy bits. After above-mentioned pretreatment, make 1588 messages from getting stamp point to popping a littleIn the process of transmission, the length of 1588 messages is always constant. In the present embodiment, due at every LANEIn 1588 messages of upper transmission, add AM, can come by this AM at a place of popping, alignd every1588 messages of the upper transmission of LANE. It will be recognized by those skilled in the art that AM herein length and32 dummy bits are only example, the length of the dummy bit position that dissimilar object message need to be reservedCan be different, can arrange flexibly according to the type of message.
102, described object message is got to stamp getting stamp point, obtain the first time stamp of described object message.
Receiving after the object message of preset length, bogey is got object message getting stamp pointTime stamp, must this object message get first time stamp at stamp point place at this.
103, detect at the described stamp point of getting the indication code that whether receives described object message.
Object message is got after stamp getting stamp point, bogey further checks whether connect getting stamp pointReceive the indication code of object message. If bogey does not detect the indication code of object message, carry out stepRapid 104; If bogey detects the indication code of object message, execution step 105.
104, the current count value that gets the first counter is as target bit; Wherein, every through oneThe individual work period, described the first counter deducts a bit number, and described bit number is described workThe bit number of putting away from popping in cycle.
First counter is set in bogey, gets when current by this first counterCarve, in protocol stack, stab point to the some bit number waiting for transmission of popping from getting. Wherein, the first counter settingGetting stamp point place.
In the present embodiment, every through a work period, the first counter is just on the basis of current count valueOn deduct a specific bit number. This bit number is in each work period, a little sends from poppingThe bit number going. In the present embodiment, set the bit number of putting away from popping in the unit interval identical, by theThe work period of one counter is set to the unit interval, and the specific bit number that the first counter is increasedBe set to the bit number of putting away from popping in the unit interval. Pop from getting to stab to put to transfer in object messageIn the process of point, bogey can get the current count value of the first counter as target bit.Wherein, target bit is bit number waiting for transmission in current time protocol stack.
Utilize the first counter unit interval of every arrival, correspondingly from the basis of current count value,Deduct this principle of bit number of going out from protocol stack in this unit interval, the present embodiment can be in real timeMeasure actual bit number waiting for transmission in protocol stack, can eliminate the delay of object message in the time of transmission and trembleMoving.
105, indicate described the first counter by total bit number of described current count value and described object messageDo and, to obtain described target bit.
In the heading of general objectives message, can carry the indication code of an object message. In step 103If the indication code of object message detected, explanation has an object message to enter protocol stack. Take up dressPut instruction the first counter on the basis of current count value, increase the length of this object message, i.e. this orderThe bit number carrying in mark message. Particularly, by the current count value of the first counter and object messageMiddle bit number do and, obtain target bit.
In the time that object message is 1588 message, actual 64 Bit datas that carried of 1588 messages, still100GBASE-R bogey has adopted 64/66 coding rule, after 1588 messages are encoded, and 1588The length of message can become 66 bits, therefore, is detecting after the indication code of 1588 messages firstThe current count value of number device can increase by 66.
106, according to described target bit and described the first time stamp, get described current time and pop a littleSecond time stamp at place.
In the present embodiment, in default each work period, the bit number a little sending out from popping is specificBit number. According to target bit and the first time stamp, get pop second o'clock an of place of current timeStamp, in the present embodiment, concrete formula is:
Second time stamp=the first time stamp+target bit/bit number.
Therefore, bogey can be made ratio by target bit waiting for transmission and bit number in protocol stack,To obtain from getting stamp point to the transmission time of popping a little, then transmission time and the first time stamp are done with, obtainTo second time stamp at a place of popping.
Delay jitter removing method in the message transmission procedure that the present embodiment provides, is entering object messageRow is got before stamp, increases the length of the bit adjustment aim message of object message, so that the length of object messageDegree reaches preset length, described object message is got to stamp getting stamp point, obtains described object messageThe first time stamp, detects at the described stamp point of getting the indication code that whether receives described object message, if not inspectionMeasure described indication code, get the current count value of the first counter as target bit, wherein,Every through a work period, described the first counter deducts a bit number, and described bit number isThe bit number of putting away from popping in the described work period, according to described target bit and described first o'clockStamp, gets pop second time stamp at a place of described current time. The present embodiment, will before getting stamp pointThe length adjustment of object message is to default length, thus bit in can real-time follow-up object message,And measure in real time bit number waiting for transmission in protocol stack by the first counter, realize and having trembled postponingMoving correction, can eliminate the delay jitter existing in message transmission procedure.
In the another kind of message transmission procedure that Fig. 3 provides for the present embodiment, delay jitter removing method showsIntention. As shown in Figure 3, the method comprises the following steps:
201,, object message is got before stamp, the bit that increases described object message is adjusted described orderThe length of mark message, so that the length of described object message reaches preset length.
202, described object message is got to stamp getting stamp point, obtain the first time stamp of described object message.
Step 201～step 202 is identical with step 101～102 in above-mentioned example, and detailed process can be referring to upperState the record of related content in embodiment, repeat no more herein.
203, described object message from described get stamp point to described in the transmitting procedure of popping a little, to describedObject message is added the correction request with described object message synchronous transfer.
In practical application, the first counter may be interfered, and makes the current counting of the first counterValue has sent larger variation, in the present embodiment, in order to ensure the accuracy of the first counter, Ke YitongOvercorrect request is proofreaied and correct the current count value of the first counter.
Bogey completes after pretreatment, transmission objectives message in protocol stack. In object message from gettingStamp point is to the transmitting procedure of popping a little, and bogey can add correction request in object message, shouldCorrection request and object message synchronous transfer. Alternatively, correction request can be bundled in object messageOr by with outside the mode followed, synchronously in protocol stack, transmit with object message. In the present embodimentBinding can be understood as, and certain bit and correction request in object message exist in synchronous regime alwaysThe upper transmission of LANE.
204, in first moment of adding described correction request, obtain described the first counter described firstThe current count value in moment is as the first bit number, and triggers the second counter simultaneously and count; Wherein,Every through a work period, described the second counter adds described bit number.
In the present embodiment, in first moment of adding correction request to object message, bogey getsThe first counter at the current count value in the first moment as the first bit number. Further, at first o'clockCarve, bogey also needs to trigger the second counter simultaneously to be counted. Wherein, in bogey, establishPut the second counter, this second counter is every through a work period, and the second counter is at current countingOn the basis of value, add a specific bit number, this bit number is a little to send from popping in the work periodThe bit number going. Wherein, correction request can be one and set high pulse, and bogey is sent out to object messageWhen giving this to set high pulse, this is set high to pulse and sends to the first counter, touch by setting high pulseSending out the second counter counts from zero. Alternatively, bogey also can trigger by other meansThe second counter, but must ensure at first time trigger the second counter.
Wherein, the second counter has the work period, in the time arriving a work period, and the second countingDevice can increase a fixed numbers. In the present embodiment, set the bit of putting away from popping in the unit intervalNumber is identical. Therefore, the work period of the second counter is set to the unit interval, and by the second counterThe fixed numbers increasing is set to the bit number of putting away from popping in the unit interval.
205, locate to detect described correction request popping, and second o'clock of described correction request detectedCarve, obtain the current count value in described the second moment and described first counting of described the second counterDevice at the current bit number in described the second moment as the second bit number.
In the present embodiment, bogey can detect in real time a place of popping and whether receive correction request.Some bit synchronous transfer in correction request and object message, when this bit reaches while popping some,Also can reach and pop a little with the correction request of object message synchronous transfer, now, bogey is being poppedPoint place just can detect correction request.
The moment that bogey correction request detected by the present embodiment is as the second moment. Bogey canTo get the current count value in the second moment from the second counter. Particularly, bogey is secondMoment sends to proofread and correct to the second counter and finishes instruction, and the second counter receives to proofread and correct and finishes after instruction,The second counter stops counting, and current count value is returned to bogey.
The present embodiment can record from a little actual bit sending out of popping in real time by the second counterNumber. When obtaining the current count value of the second counter, bogey also need to be from the first counterGet the current count value in the second moment as the second bit number.
206, according to described the first bit number, described the second bit number and described current count value, obtainDescribed target bit.
Getting after the current count value of the first bit number, the second bit number and the second counter, holdCarry device and can, according to default formula, can obtain target bit. Wherein, default formula is as followsShown in:
Target bit=the second bit number+(current count value-the first bit number of the second counter).
In above-mentioned steps 202 and step 203, the first bit number is the association in the prediction of the first momentBit number waiting for transmission in view stack, and the current count value of the second counter is that object message is from getting stamp point biographyBe passed in the process of popping a little the actual bit number a little sending from popping. The current counting of the second counterValue with the first bit number between difference, as prediction the bit number of going out from protocol stack with reality fromThe error bit number of the bit number that protocol stack is gone out. Getting after this error bit number, bogey willThis error bit and the second bit number and value, as from getting stamp point to the process of popping a little, Ke YicongThe protocol stack a little actual target bit sending out of popping.
In practical application, bogey does not need in real time the first counter to be proofreaied and correct, can the cycleProperty is proofreaied and correct the first counter, to ensure the accuracy of current count value of the first counter. When obtainingAfter getting the current count value of the second counter and the difference of the first bit number, bogey can be in order toThe first counter is proofreaied and correct with above-mentioned error bit number, by the current count value of the first counter moreNew is target bit, thus the error that corrigendum the first counter occurs. Reach at upper once calibration cycleAfter arriving, the object message of again transmitting by current time, enters the current count value of the first counterRow is proofreaied and correct.
207, according to described target bit and described the first time stamp, get described current time and pop a littleSecond time stamp at place.
Particularly, obtaining after target bit, bogey by target bit and in the unit interval fromThe bit number a little sending out of popping is made ratio, obtains from getting stamp point to the propagation delay time popping a little.Wherein, the bit number a little sending out from popping in each unit interval is identical bit number.
Delay jitter removing method in the message transmission procedure that the present embodiment provides, is entering object messageRow is got before stamp, increases the length of the bit adjustment aim message of object message, so that the length of object messageDegree reaches preset length, transfers to the process of popping a little, to object message in object message from getting stamp pointAdd and the correction request of object message synchronous transfer, and add the first moment of correction request, obtain theThe current value of one counter, as the first bit number, triggers the second counter simultaneously and counts, and is going outStack point place detects correction request, and in the second moment that correction request detected, obtains the second counterCurrent count value and at the current count value of the first counter as the second bit number, according to default schoolTest formula, according to the first bit number, the second bit number and the second counter current count value, getFrom getting stamp point to the propagation delay time of popping a little. The present embodiment is before getting stamp point, by the length of object messageAdjust to default length, thus the bit in can real-time follow-up object message, and by theOne counter is measured bit number waiting for transmission in protocol stack in real time, has realized the correction to delay jitter,Can get rid of delay jitter.
Further, by correction request, the first counter is proofreaied and correct, to ensure the first counterThe correctness of current count value, improves the accuracy rate of obtaining propagation delay time, is conducive to the synchronous transfer of message.
The knot of delay jitter cancellation element in a kind of message transmission procedure that Fig. 4 provides for the embodiment of the present inventionStructure schematic diagram. In the message transmission procedure that following embodiment provides, delay jitter cancellation element can be agreementBogey. Transfer to the process of popping a little as example taking object message from getting stamp point, following enforcement is describedThe message transmissions time delay device that example provides. As shown in Figure 4, this bogey comprises: pretreatment module 41,Get stamp module 42, first detection module 43, the first counting module 44, acquisition module 45 and computing module46。
Wherein, for the length that ensures object message get stamp point to the length between popping a little constant orCan expect, so that the propagation delay time of object message is carried out to real-time tracking. Object message is being gotBefore stamp, pretreatment module 41 increases the bit of object message, and the length of adjustment aim message, so that orderThe length of mark message reaches default length. Particularly, file destination is carried out to pretreated process, canReferring to the record of related content in above-described embodiment, repeat no more herein.
Pretreatment module 41 with get stamp module 42 be connected, after pretreatment by the object message of preset lengthSend to delivery piece 42. Get stamp module 42 and object message is got to time stamp getting stamp point, must be at this orderMark message is being got first time stamp at stamp point place.
Get stamp module 42 be connected with first detection module 43, get stamp put object message is got after stamp,First detection module 43 detects the indication code that whether receives object message getting stamp point. In the present embodiment,First counting module 44 is set in bogey, and alternatively, the first counting module 44 can beOne counter. In the present embodiment, get in current time protocol stack from getting by this first counterStamp point is to the reality bit number waiting for transmission of popping. Wherein, the first counter is arranged on and gets stamp point place.
Wherein, every through a work period, the first counter just deducts on the basis of current count valueA specific bit number. This bit number is in each work period, the ratio a little sending out from poppingSpecial number. In the present embodiment, set the bit number of putting away from popping in the unit interval identical, by the first countingThe work period of device is set to the unit interval, and the specific bit number that the first counter increases is set toThe bit number of putting away from popping in unit interval.
Utilize the first counter unit interval of every arrival, correspondingly from the basis of current count value,Deduct the bit number of going out from protocol stack in this unit interval, the first counter can be predicted in real timeTo bit number waiting for transmission in protocol stack. To be transmitted in the protocol stack that or not first counter does not predict in the same timeBit number be different, using the current count value of the first counter as target bit. The present embodimentBy the above-mentioned counting process of the first counter, can eliminate the delay jitter of object message in the time of transmission.
Also be connected with acquisition module 45 at first detection module 43, the instruction of object message do not detectedWhen code, acquisition module 45 can get current count value from the first counting module 44, as target ratioSpecial number. Wherein, target bit is bit number waiting for transmission in current time protocol stack.
Further, in the heading of general objectives message, can carry the indication code of an object message. WhenWhen first detection module 43 detects the indication code of object message, illustrate that an object message enters agreementStack. First detection module 43 can indicate the first counting module 44 on the basis of current count value, increasesThe total bit number that adds object message, obtains target bit.
In the time that object message is 1588 message, actual 64 Bit datas that carried of 1588 messages, still100GBASE-R bogey has adopted 64/66 coding rule, after 1588 messages are encoded, and 1588The length of message can become 66 bits, therefore, is detecting after the indication code of 1588 messages firstThe current count value of number device can increase by 66.
In the present embodiment, in default each work period, the bit number a little sending out from popping is specificBit number. Acquisition module 45 is connected with computing module 46, according to target bit and the first time stamp,Get pop second time stamp at a place of current time, in the present embodiment, concrete formula is:
Second time stamp=the first time stamp+target bit/bit number.
Therefore, computing module 46 can be made ratio by target bit and bit number, to obtain from getting stampPoint is to the transmission time of popping a little, then by transmission time and the first time stamp work with, a place that obtains poppingThe second time stamp.
Delay jitter cancellation element in the message transmission procedure that the present embodiment provides, is entering object messageRow is got before stamp, increases the length of the bit adjustment aim message of object message, so that the length of object messageDegree reaches preset length, object message is got to stamp getting stamp point, obtains the first time stamp of object message,Getting to stab to put to detect whether receive the indication code of object message, if indication code do not detected, getThe current count value of the first counter is as target bit, wherein, every through a work period, theOne counter deducts a bit number, and bit number is the bit number of putting away from popping in the work period,According to target bit and the first time stamp, get pop second time stamp at a place of current time. This enforcementExample, before getting stamp point, arrives default length by the length adjustment of object message, thereby can real-time trackingBit in measurement target message, and measure in real time in protocol stack actual to be transmitted by the first counterTarget bit, realized the correction to delay jitter, can eliminate to exist in message transmission procedureDelay jitter.
Fig. 5 for the embodiment of the present invention provide delay jitter cancellation element in another kind of message transmission procedureStructural representation. As shown in Figure 5, this device except comprise pretreatment module 41 in above-mentioned example,Get stamp module 42, first detection module 43, the first counting module 44, acquisition module 45 and computing moduleOutside 46, also comprise: add module 47, the second counting module 48, trigger module 49, the second detectionModule 50 and writing module 51.
About pretreatment module 41, get stamp module 42, first detection module 43, the first counting module 44,The associated description of acquisition module 45 and computing module 46 and annexation, can be referring in above-described embodimentThe record of related content repeats no more herein.
After pretreatment module 41 is to object message pretreatment, the process of transmission objectives message in protocol stackIn, add module 47 can to object message add one with the correction request of object message synchronous transfer.Alternatively, correction request can be bundled in object message or by with outside the mode followed, with orderMark message synchronously transmits in protocol stack. In the present embodiment, correction request will be added to object messageMoment became for the first moment.
In the present embodiment, in first moment of adding correction request to object message, acquisition module 45 obtainsThe first counting module 44 at the current count value in the first moment as the first bit number. Further,One moment trigger module 49 triggers the second counting module 48 simultaneously and counts.
In the present embodiment, correction request can be one and set high pulse, adds module 47 and sends out to object messageWhen giving this to set high pulse, and this is set high to pulse and sends to the second counting module 48, set high by thisPulse-triggered the second counting module 48 is counted. Wherein, the second counting module 48 can be a meterNumber device. Alternatively, trigger by other means the second counting module 48, but must ensure at first o'clockCarve and trigger the second counting module 48. Wherein, the process that the second counting module 48 is counted, can be referring to above-mentionedIn example, the record of related content repeats no more herein.
In the present embodiment, the second detection module 50 is arranged on a place of popping, and detects in real time a place of popping to beThe no correction request that receives. Some bit synchronous transfer in correction request and object message, when this ratioWhen special position is transferred to and pops, this correction request also synchronously arrives and pops a little, now, and the second detection module50 at a place of popping, and correction request can be detected. In the present embodiment, the second detection module 50 is examinedMeasure the moment of correction request as the second moment, at the second moment second detection module 50 to the second countingModule 48 sends to proofread and correct and finishes instruction. The second counter 48 receives to proofread and correct and finishes after instruction, and secondDigital-to-analogue piece 48 stops counting, and the current count value in the second 48 second moment of counting module is sent to and obtainedModule 45. In the present embodiment, can record in real time from a reality of popping and send out by the second counting module 48The bit number of going out.
When obtaining the current count value in the second 48 second moment of counting module, acquisition module 45 also needsThe current count value that will get for the second moment from the first counting module 44 is as the second bit number.
At the current count value that gets the first bit number, the second bit number and the second counting module 48After, acquisition module 45 can, according to default formula, can obtain target bit. About acquisition module45 according to default formula, obtains the process of target bit, can be referring to related content in above-described embodimentRecord, repeat no more herein.
In practical application, bogey does not need in real time the first counter to be proofreaied and correct, can the cycleProperty is proofreaied and correct the first counter, to ensure the accuracy of current count value of the first counter. ObtainModule 45 is connected with the first counting module 44, when getting the current count value and of the second counterAfter the difference of one bit number, the first counting module 44 can utilize above-mentioned error bit number to firstCounting module 44 is proofreaied and correct, and the current count value of the first counting module 44 is updated to target bitsNumber, thereby the error of the first counter that corrigendum occurs. Upper once after calibration cycle reaches, againThe object message of transmitting by current time, proofreaies and correct the first counter.
Obtaining after target bit, counting module 46 by target bit and in the unit interval from popping a littleThe bit number sending out is made ratio, obtains from getting stamp point to the propagation delay time popping a little. Wherein,The bit number a little sending out from popping in each unit interval is identical bit number.
In the present embodiment, the writing module 51 in delay jitter cancellation element in this message transmission procedureFrom getting stamp point to popping a process of transmission objectives message, to the reserved sky of pretreatment module 41In white bit, write the check results of object message being carried out to checking treatment. Or stabbing point extremely from gettingPop in a process of transmission objectives message, writing module 51 is to the reserved blank of pretreatment module 41In bit, write check results and the AM of object message.
Delay jitter cancellation element in the message transmission procedure that the present embodiment provides, by object messageGet before stamp, increase the length of the bit adjustment aim message of object message, real-time follow-up is arrivedFrom getting stamp point to the propagation delay time of popping a little, according to this propagation delay time and first time stamp of getting stamp point place, obtainGet second time stamp of popping a little. The present embodiment, before getting stamp point, arrives the length adjustment of object messageDefault length, thereby the bit in can real-time follow-up object message, and by the first countingModule is measured bit number waiting for transmission in protocol stack, has realized the correction to delay jitter, can get rid ofDelay jitter. Further, by correction request, the first counting module is proofreaied and correct, to ensure firstThe correctness of the current count value of counting module, improves the accuracy rate of obtaining propagation delay time, is conducive to messageSynchronous transfer.
Further, by correction request, the first counter is proofreaied and correct, to ensure the first counterThe correctness of current count value, improves the accuracy rate of obtaining propagation delay time, is conducive to the synchronous transfer of message.
As a kind of possible implementation, in the message transmission procedure in the present embodiment, delay jitter is eliminatedDevice can be applicable in 1588 messages. Fig. 6 is delay jitter cancellation element in 1588 message transmission proceduresStructural representation. As shown in Figure 6, this transmission delay acquisition device is to Ethernet 100GBASE-RThe one of bogey is improved. Particularly, 100GBASE-R bogey comprises: Ethernet encapsulation(EthernetEncapsulation) module 1, pretreatment (AM-Pre-insert) module 2, timestamp obtainGet and packet amendment (1588GetTimestamp&ModifyPacket) module 3, frame sequence verificationCalculate (FrameCheckSequenceCalculate is called for short FCSCalculate) module 4, first advancedDequeue (FirstInputFirstOutput is called for short FIFO) 5, encoder (Encoder) 6, scramblingDevice (Scramble) 7, AM processor (AlignmentMarkerProcess) 8, distributor (Distribution)9, combiner (Gearbox) 10, get stamp module 11, first detection module 12, the first counter 13,Acquisition module 14, computing module 15, interpolation module 16, the second detection module 17 and the second counter 18.
The data flow of 1588 messages enters Ethernet package module 1, and Ethernet package module 1 is to 1588 reportsLiterary composition encapsulates, and then by pretreatment module 2, each 1588 messages is increased to bit, adjustsThe length of 1588 messages, makes the length of 1588 messages reach predetermined length. 100GBASE bogeyOn be provided with 20 LANE, on every LANE, transmitted 1588 messages. Particularly, locate in advanceReason module 2 increases the dummy bit position of 96 bits in advance for 1588 messages on every LANE. Pre-placeReason module 2 is that 1588 messages increase AM in 64 reserved bits.
Pretreatment module 2 is after the AM alignment of each 1588 messages, by each 1588 messagesLANE, sends to acquisition time stamp and packet modified module 3, and is arranged on the stamp of getting of getting stamp point placeModule 11 is got stamp to 1588 messages, obtains the first time stamp, is designated as and gets stamp value (ts_value).
Also be provided with first detection module 12 getting stamp point place, this first detection module 12 is for detection of beingThe no indication code that receives 1588 messages. In the time that 1588 messages have just entered protocol stack, first detection module12 can detect the indication code of 1588 messages. In reality, on 100GBASE-R bogeyBe provided with 20 LANE, pretreatment module 2 can be chosen 1588 messages on one of them LANEIndication code, send to first detection module 12. As, can choose 1588 of the upper transmission of LANE0 and reportThe indication code of literary composition sends first detection module 12. Detecting after indication code, can indicate the first counterThe 13 upper whole total bit numbers that add 1588 messages at current count value. In the present embodiment, firstNumber device 13 increases by 66 on current count value. In reality, the bit number that carries of each 1588 message is 64Bit, but because encoder 6 adopts 64/66 coding rule, after coding, can be by 64 bitsChange into 66 bits, therefore, the first counter 13 need to increase by 66 bits. The first counter 13 exists1588 messages are from getting stamp point to the process of a transmission of popping, every through a work period, just from currentIn count value, deduct a fixing bit number, to predict not in the same time bit waiting for transmission in protocol stackNumber. Wherein, fixing bit number is from a bit number of going out of popping in the work period. This enforcementIn example, each work period is identical from a bit number of going out of popping.
Add module 16 and obtain with packet modified module 3 is parallel and arrange with timestamp, at 1588 messagesGet stamp point place, add module 16 periodically to adding in 1588 messages with 1588 message synchronous transferCorrection request (adjust_start). This adjust_start is one and sets high pulse. In the present embodiment, by interpolationThe moment that module 16 sets high pulse to 1588 messages interpolations was designated as for the first moment. Acquisition module 14 obtainsWhen one moment, the current count value of the first counter 13 is as the first bit number.
Adding the first moment that sets high pulse to 1588 messages, adding module 16 needs to set high pulseSend to the second counter 18, trigger the second counter 18 and count from zero. The second counter 18 is openedBegin after counting, every through a work period, just, on the basis of current count value, increase by one and fixBit number be from a bit number sending out of popping in the work period.
To 1588 message transmissions that set high pulse be added to frame sequence verification computing module 4, frame sequence schoolTest computing module 4 1588 messages are carried out to FCSCalculate processing, can obtain the school of 32Test result, the check results of 32 is write to 32 remaining dummy bits. Through FIFO5, codingAfter the processing of device 6 and scrambler 7,1588 messages are input to AM processor 8.
AM processor 8 shifts out the transmission Skew between each 1588 messages, aligns each 1588The AM of message. By distributor 9 and combiner 10,1588 messages on 20 LANE being closed to road arrivesOn a LANE. The second detection module 17 is arranged on a place of popping, for locating to detect poppingAdjust_start, if adjust_start detected, sends one to the second counter 18 immediately and proofreaies and correct knotBundle request (adjust_end). Receiving after adjust_end, the second counter 18 stops calculating, andCurrent count value is sent to acquisition module 14 as proofreading and correct result (adjust_result). In the present embodimentTo detect that the moment of adjust_start was set as for the second moment at a place of popping. Acquisition module 14 also needsGet the current count value of second moment the first counter 13 as the second bit number.
Getting the first bit number, the second bit number and the second counter 18 in the second momentAfter current count value, acquisition module 14 can get target bit. Wherein, acquisition module 14Obtain the process of target bit, can be referring to the record of related content in above-described embodiment, herein notRepeat again.
Getting after the target bit of 1588 messages, computing module 15 can be according to the first time stamp andTarget bit, obtains 1588 messages at second time stamp at a place of popping.
Delay jitter cancellation element in 1588 message transmission procedures that the present embodiment provides, by 1588Message is got before stamp, increases the length of the bit adjustment aim message of 1588 messages, and real-time tracking is surveyedAmount, to stabbing point to the propagation delay time of popping a little from getting, stabs with getting the first time stamp that point is located according to this propagation delay time,Get second time stamp of popping a little. The present embodiment is before getting stamp point, by the length adjustment of 1588 messagesTo default length, thus can real-time follow-up object message, and real-time by the first counterBit number waiting for transmission in protocol stack is measured on ground, has eliminated the delay that 1588 messages exist in transmitting procedureShake, can revise propagation delay time, and the accuracy of the propagation delay time obtained that provides high is favourableIn the synchronous transfer of 1588 messages.
Finally it should be noted that: above each embodiment is only in order to technical scheme of the present invention to be described, but not rightIts restriction; Although the present invention is had been described in detail with reference to aforementioned each embodiment, this area commonTechnical staff is to be understood that: its technical scheme that still can record aforementioned each embodiment is modified,Or some or all of technical characterictic is wherein equal to replacement; And these amendments or replacement, andDo not make the essence of appropriate technical solution depart from the scope of various embodiments of the present invention technical scheme.
Claims (16)
1. a delay jitter removing method in message transmission procedure, is characterized in that, comprising:
Object message is got before stamp, the bit that increases described object message is adjusted the length of described object message, so that the length of described object message reaches preset length;
Described object message is got to stamp getting stamp point, obtain the first time stamp of described object message;
Detect at the described stamp point of getting the indication code that whether receives described object message;
If described indication code do not detected, get the current count value of the first counter as target bit; Wherein, every through a work period, described the first counter deducts a bit number, and described bit number is the bit number of putting away from popping in the described work period;
According to described target bit and described the first time stamp, get pop second time stamp at a place of described current time.
2. delay jitter removing method in message transmission procedure according to claim 1, is characterized in that, also comprises:
If described indication code detected, indicate described the first counter that total bit number of described object message is added to described current count value, to obtain described target bit.
3. delay jitter removing method in message transmission procedure according to claim 1, is characterized in that, also comprises:
Described object message from described get stamp point to described in the transmitting procedure of popping a little, add and the correction request of described object message synchronous transfer to described object message;
Adding the first moment of described correction request, obtain described the first counter at the current count value in described the first moment as the first bit number, and trigger the second counter simultaneously and count; Wherein, every through a work period, described the second counter adds described bit number;
Locate to detect described correction request described popping, and the current bit number that obtains the second moment described in the current count value in described second the second moment of counter and described the first counter is as the second bit number; Wherein, described the second moment is the moment that described correction detected;
The described current count value that obtains the first counter comprises as target bit:
According to the described current count value of described the first bit number, described the second bit number and described the second counter, obtain described target bit.
4. delay jitter removing method in message transmission procedure according to claim 3, is characterized in that, described according to described the first bit number, described the second bit number and described current count value, obtains described target bit and comprises:
By the difference of the described current count value of described the second counter and described the first bit number, as error bit number;
By described the second bit number and described error bit number and value, as described target bit.
5. delay jitter removing method in message transmission procedure according to claim 4, is characterized in that, described according to described target bit and described the first time stamp, gets pop second time stamp at a place of described current time and comprises:
Described target bit and described bit number are made to ratio, obtain from described get stamp point to described in transmission time of popping a little;
By the described transmission time and described first time stamp do and, obtain described the second time stamp.
6. delay jitter removing method in message transmission procedure according to claim 4, is characterized in that, described by described the second bit number and described error bit number and value, after described target bit, also comprise:
Utilize described error bit number to revise described the first counter, the current count value of described the first counter is updated to described target bit.
7. delay jitter removing method in message transmission procedure according to claim 1, it is characterized in that, described object message is got before stamp, the bit that increases described object message is adjusted the length of described object message, comprises so that the length of described object message reaches preset length:
Object message is got before stamp, for adjusting the length of described object message in the dummy bit position of the reserved length-specific of described object message, so that the length of described object message reaches preset length; Wherein, described dummy bit position for from described get stamp point to described in a process for the described object message of transmission of popping, write the check results of described object message being carried out to checking treatment.
8. delay jitter removing method in message transmission procedure according to claim 1, it is characterized in that, described object message is got before stamp, the bit that increases described object message is adjusted the length of described object message, comprises so that the length of described object message reaches preset length:
Object message is got before stamp, in described object message, insert alignment identification AM, and be the dummy bit position of the reserved length-specific of described object message; Wherein, described dummy bit position for from described get stamp point to described in a process for the described object message of transmission of popping, write the check results of described object message being carried out to checking treatment; Described AM is used at a described alignment identification AM for the described object message of alignment that pops.
9. a delay jitter cancellation element in message transmission procedure, is characterized in that, comprising:
Pretreatment module, for object message is got before stamp, the bit that increases described object message is adjusted the length of described object message, so that the length of described object message reaches preset length;
Get stamp module, for described object message being got to stamp getting stamp point, obtain the first time stamp of described object message;
First detection module, for detecting at the described stamp point of getting the indication code that whether receives described object message;
The first counting module, for the transmitting procedure in described object message, counts described object message; Wherein, every through a work period, described the first counting module deducts a bit number, and described bit number is the bit number of putting away from popping in the described work period;
Acquisition module, if for described indication code not detected, gets the current count value of described the first counting module as target bit;
Computing module, for according to described target bit and described the first time stamp, gets pop second time stamp at a place of described current time.
10. delay jitter cancellation element in message transmission procedure according to claim 9, it is characterized in that, described acquisition module, if also for described indication code being detected, the total bit number of the described current count value of described the first counting module and described object message is done and, obtain described target bit.
11. according to delay jitter cancellation element in the message transmission procedure described in claim 9 or 10, it is characterized in that, also comprises:
Add module, for described object message from described get stamp point to described in the transmitting procedure of popping a little, add and the correction request of described object message synchronous transfer to described object message;
Described acquisition module, also for adding the first moment of described correction request, obtain described the first counting module at the current count value in described the first moment as the first bit number; And obtain the current count value in second the second moment of counting module and described the first counting module at the current bit number in described the second moment as the second bit number, according to the described current count value of described the first bit number, described the second bit number and described the second counter, obtain described target bit, wherein, the second moment was the moment that the second detection module detects described correction request;
The second counting module, for counting the described bit number a little sending of popping; Wherein, every through a work period, described the second counting module adds described bit number;
Trigger module, for the first moment adding described correction request, triggers described the second counting module simultaneously and counts;
Described the second detection module, for locating to detect described correction request described popping.
Delay jitter cancellation element in 12. message transmission procedures according to claim 11, it is characterized in that, described acquisition module is specifically for by the difference of the described current count value of described the second counter and described the first bit number, as error bit number, by described the second bit number and described error bit number and value, as described target bit.
Delay jitter cancellation element in 13. message transmission procedures according to claim 12, it is characterized in that, described computing module is specifically for making ratio by described target bit and described bit number, obtain from described get stamp point to described in transmission time of popping a little, by the described transmission time and described first time stamp do and, obtain described the second time stamp.
Delay jitter cancellation element in 14. message transmission procedures according to claim 12, it is characterized in that, described the first counting module, also, for utilizing described error bit number to revise described the first counting module, the current count value of described the first counting module is updated to described target bit.
Delay jitter cancellation element in 15. message transmission procedures according to claim 9, it is characterized in that, described pretreatment module is specifically for getting before stamp object message, for adjusting the length of described object message in the dummy bit position of the reserved length-specific of described object message, so that the length of described object message reaches preset length; Wherein, described dummy bit position for from described get stamp point to described in a process for the described object message of transmission of popping, write the check results of described object message being carried out to checking treatment.
16. according to delay jitter cancellation element in the message transmission procedure described in right 9, it is characterized in that, described pretreatment module is specifically for getting before stamp object message, in described object message, insert alignment identification AM, and be the dummy bit position of the reserved length-specific of described object message; Wherein, described dummy bit position for from described get stamp point to described in a process for the described object message of transmission of popping, write the check results of described object message being carried out to checking treatment; Described AM is used at a described alignment identification AM for the described object message of alignment that pops.
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| CN110224775B (en) * | 2018-03-01 | 2021-10-29 | 中兴通讯股份有限公司 | Method, device and equipment for determining time information |
| CN112910588A (en) * | 2019-11-19 | 2021-06-04 | 深圳市中兴微电子技术有限公司 | Ethernet time synchronization method and device |
| CN112202519A (en) * | 2020-08-26 | 2021-01-08 | 浙江双成电气有限公司 | Method for controlling message transmission delay jitter |
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| CN102130735A (en) * | 2010-11-09 | 2011-07-20 | 华为技术有限公司 | Transmission equipment and method thereof for realizing synchronization of clock and time |
| CN102232278A (en) * | 2011-06-23 | 2011-11-02 | 华为技术有限公司 | Method and device for detecting 1588 equipment performance |
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