CN107395307B - A kind of clock synchronizing method and equipment - Google Patents
A kind of clock synchronizing method and equipment Download PDFInfo
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- CN107395307B CN107395307B CN201710565171.2A CN201710565171A CN107395307B CN 107395307 B CN107395307 B CN 107395307B CN 201710565171 A CN201710565171 A CN 201710565171A CN 107395307 B CN107395307 B CN 107395307B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0638—Clock or time synchronisation among nodes; Internode synchronisation
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0638—Clock or time synchronisation among nodes; Internode synchronisation
- H04J3/0641—Change of the master or reference, e.g. take-over or failure of the master
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0638—Clock or time synchronisation among nodes; Internode synchronisation
- H04J3/0652—Synchronisation among time division multiple access [TDMA] nodes, e.g. time triggered protocol [TTP]
- H04J3/0655—Synchronisation among time division multiple access [TDMA] nodes, e.g. time triggered protocol [TTP] using timestamps
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- Synchronisation In Digital Transmission Systems (AREA)
Abstract
The embodiment of the invention discloses a kind of clock synchronizing method and equipment, the clock synchronizing method includes: the equipment where local clock and when the upstream equipment where upstream clock connects, when the port clock state of equipment is from clock or only to do from clock, and the port clock state of upstream equipment be master clock when, equipment is obtained from upstream equipment and is recorded for synchronous clock information, and local clock is synchronized to upstream clock according to the clock information；When equipment and upstream equipment disconnect suddenly, the clock information according to recorded in synchronizing process is modified compensation to local clock.The embodiment of the present invention is when clock source is lost, compensation is modified to local clock, it is synchronous with clock source progress clock to continue to, to achieve the purpose that clock is synchronous for being controlled in certain period of time from the time difference of clock and clock source in a lesser range.
Description
Technical field
The present invention relates to simultaneous techniques, espespecially a kind of clock synchronizing method and equipment.
Background technique
In the field of communications, clock, which synchronizes, plays a very important role to other business such as voice, video tool.Realize that clock is same
The method of step mainly includes the modes such as link layer hardware transport and the transmission of message software layer, and national standard IEEE1588v2 agreement is (accurate
Time protocol (PTP, Precision Time Protocol)) based on message switching method realization clock frequency and clock phase
When it is present when clock source, it is synchronous to carry out clock according to the clock information of Receive message master clock from clock for synchronizing function.
From the clock synchronizing method of clock and clock source when national standard IEEE 1588v2 agreement defines clock source when it is present,
But if clock source is lost, it will be lost from clock and continue the synchronous reference source of clock, without reference to related content in agreement.
Summary of the invention
The embodiment of the invention provides a kind of clock synchronizing method and equipment, can when clock source is lost, from clock after
The continuous correction-compensation for carrying out local clock, it is synchronous with clock source progress clock to continue to, thus will be from clock and clock
The time difference in source is controlled in certain period of time in a lesser range, achievees the purpose that clock is synchronous.
The embodiment of the invention provides a kind of clock synchronizing methods, comprising:
When upstream equipment where equipment and upstream clock where local clock connects, when the port clock state of equipment
From clock or only to do from clock, and when the port clock state of upstream equipment is master clock, equipment obtains simultaneously from upstream equipment
Local clock is synchronized to upstream clock according to the clock information for synchronous clock information by record；
When equipment and upstream equipment disconnect suddenly, the clock information according to recorded in synchronizing process carries out local clock
Correction-compensation.
Optionally, the clock information includes for determining a group or more of for the synchronous time of time difference
Stamp；
Local clock, which is synchronized to upstream clock, according to the clock information includes:
Determine and record that this group of timestamp corresponding correction time for the first time is poor based on each group of timestamp corresponding time difference；
Determine and record frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the first preset time, and benefit
Secondary correction is carried out to the corresponding difference of correction time for the first time of each group of timestamp with frequency offset correction amount obtained, obtains and records
This group of timestamp corresponding secondary correction time difference；
Every the second preset time according to the last one the secondary correction time difference pair obtained in second preset time
It is synchronous that local clock carries out clock.
Optionally,
It is described that the corresponding difference packet of correction time for the first time of this group of timestamp is determined based on each group of timestamp corresponding time difference
It includes:
Wherein, Fi is that i-th group of timestamp corresponding correction time for the first time is poor,
Offseti is i-th of time difference according to determined by i-th group of timestamp.
Optionally, the secondary correction time difference obtains in the following manner:
In first preset time of determination every group of timestamp relative to the frequency offset correction amount of first group of timestamp include: by
One group of timestamp of setting is relative to the frequency offset correction amount of first group of timestamp as the first pre- timing in first preset time
Frequency offset correction amount of the interior every group of timestamp relative to first group of timestamp.
Optionally, this method comprises:
When a certain group of timestamp corresponding secondary correction time difference is greater than the preset time difference in second preset time
When threshold value, it is synchronous that clock is carried out according to a certain group of timestamp corresponding secondary correction time difference.
Optionally,
Every group of timestamp includes: relative to the frequency offset correction amount of first group of timestamp in first preset time of determination
Determine that i-th group of timestamp is relative in the first preset time according to formula fi=(ti2-t12)-(ti1-t11)
The frequency offset correction amount of one group of timestamp；Wherein, i is the integer more than or equal to 1, and fi is i-th group of time in the first preset time
The frequency offset correction amount relative to first group of timestamp is stabbed, ti2 is to receive first event in i-th group of timestamp in the first preset time
The timestamp of message, t12 are the timestamp for receiving first event message in the first preset time in the 1st group of timestamp, ti1 the
I-th group of timestamp middle and upper reaches equipment sends the timestamp of first event message in one preset time, and t11 is in the first preset time
1st group of timestamp middle and upper reaches equipment sends the timestamp of first event message.
Optionally,
It is described to carry out secondary correction using for the first time correction time difference of the frequency offset correction amount obtained to corresponding timestamp,
Obtaining this group of timestamp corresponding secondary correction time difference includes:
I-th group of timestamp corresponding secondary correction time in the first preset time is calculated according to formula CorFi=Fi-fi
Difference；
Wherein i is the integer more than or equal to 1, and CorFi is the corresponding secondary school of i-th group of timestamp in the first preset time
Positive time difference, Fi are that i-th group of timestamp corresponding correction time for the first time of acquisition in the first preset time is poor, and fi is first default
The corresponding frequency offset correction amount of i-th group of timestamp in time.
Optionally,
Clock information recorded in the synchronizing process includes: that the correction time for the first time of every group of timestamp is poor, frequency offset correction
Amount,
The clock information according to recorded in synchronizing process is modified compensation to local clock and includes:
According to formula
Compensation is modified to the local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first first default
The corresponding frequency offset correction amount of m1 group timestamp in time, f (m2/T2) are m2 group timestamp in the 2nd the first preset time
Corresponding frequency offset correction amount ... ..., f (mn/Tn) are the corresponding frequency offset correction of mn group timestamp in n-th of first preset times
Amount, T1 are the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F
(m1/T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd
M2 group timestamp corresponding correction time for the first time is poor in first preset time ... ..., F (mn/Tn) be n-th first it is default when
In mn group timestamp corresponding correction time for the first time it is poor, n is the integer more than or equal to 1.
Optionally,
Clock information recorded in the synchronizing process includes: that the correction time for the first time of every group of timestamp is poor, frequency correction
Amount and secondary correction time value,
The clock information according to recorded in synchronizing process is modified compensation to local clock and includes:
When the precision of local clock crystal oscillator is higher than predetermined value, every third preset time according to being obtained in synchronizing process
The each group of timestamp corresponding secondary correction time difference, compensation is modified to the local clock with the sequence of inverted order；
Otherwise, according to formula
Compensation is modified to the local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first first default
The corresponding frequency offset correction amount of m1 group timestamp in time, f (m2/T2) are m2 group timestamp in the 2nd the first preset time
Corresponding frequency offset correction amount ... ..., f (mn/Tn) are the corresponding frequency offset correction of mn group timestamp in n-th of first preset times
Amount, T1 are the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F
(m1/T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd
M2 group timestamp corresponding correction time for the first time is poor in first preset time ... ..., F (mn/Tn) be n-th first it is default when
In mn group timestamp corresponding correction time for the first time it is poor, n is the integer more than or equal to 1.
The embodiment of the present invention also proposed a kind of equipment, comprising:
Obtain module, when for connect with the upstream equipment where upstream clock, when port clock state for from clock or
It only does from clock, and when the port clock state of upstream equipment is master clock, obtains and recorded for synchronization from upstream equipment
Clock information；
Synchronization module, for local clock to be synchronized to upstream clock according to clock information；
Compensating module, for when being disconnected suddenly with upstream equipment, the clock information pair according to recorded in synchronizing process
Local clock is modified compensation.
Optionally, the clock information includes for determining a group or more of for the synchronous time of time difference
Stamp；
The synchronization module is specifically used for:
Determine and record that this group of timestamp corresponding correction time for the first time is poor based on each group of timestamp corresponding time difference；
Determine and record frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the first preset time, and benefit
Secondary correction is carried out to the corresponding difference of correction time for the first time of each group of timestamp with frequency offset correction amount obtained, obtains and records
This group of timestamp corresponding secondary correction time difference；
Every the second preset time according to the last one the secondary correction time difference pair obtained in second preset time
It is synchronous that local clock carries out clock.
Optionally, the compensating module is specifically used for:
When being disconnected suddenly with upstream equipment,
According to formula
Compensation is modified to the local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first first default
The corresponding frequency offset correction amount of m1 group timestamp in time, f (m2/T2) are m2 group timestamp in the 2nd the first preset time
Corresponding frequency offset correction amount ... ..., f (mn/Tn) are the corresponding frequency offset correction of mn group timestamp in n-th of first preset times
Amount, T1 are the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F
(m1/T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd
M2 group timestamp corresponding correction time for the first time is poor in first preset time ... ..., F (mn/Tn) be n-th first it is default when
In mn group timestamp corresponding correction time for the first time it is poor, n is the integer more than or equal to 1.
The embodiment of the present invention also proposed a kind of equipment, comprising: the port Precision Time Protocol PTP, processor and computer
Readable storage medium storing program for executing；
The port PTP, for obtaining clock information from upstream equipment；
It is stored with instruction in the computer readable storage medium, when described instruction is executed by the processor, realizes
Following steps:
When being connect with the upstream equipment where upstream clock, when the port clock state of the port PTP is from clock or only to do
From clock, and when the port clock state of the port PTP of upstream equipment is master clock, the control port PTP is obtained from upstream equipment
For synchronous clock information, and recording clock information；
Local clock is synchronized to upstream clock according to clock information；
When disconnecting suddenly with upstream equipment, the clock information according to recorded in synchronizing process repairs local clock
Positive compensation.
Compared with the relevant technologies, the embodiment of the present invention includes: it is upper where the equipment and upstream clock where local clock
When swimming equipment connection, when the port clock state of equipment is from clock or only to do from clock, and the port clock shape of upstream equipment
When state is master clock, equipment is obtained from upstream equipment and is recorded for synchronous clock information, and will be local according to clock information
Clock is synchronized to upstream clock；When equipment and upstream equipment disconnect suddenly, equipment clock according to recorded in synchronizing process
Information is modified compensation to local clock.Scheme through the embodiment of the present invention, when clock source lose when, i.e., upstream equipment with
When equipment disconnects suddenly, equipment clock information according to recorded in synchronizing process is modified compensation to local clock, with into
The continuation of one step is synchronous with clock source progress clock, thus by controlling in certain period of time from the time difference of clock and clock source
In a lesser range, achieve the purpose that clock is synchronous.
Other features and advantages of the present invention will be illustrated in the following description, also, partly becomes from specification
It obtains it is clear that understand through the implementation of the invention.The objectives and other advantages of the invention can be by specification, right
Specifically noted structure is achieved and obtained in claim and attached drawing.
Detailed description of the invention
Attached drawing is used to provide to further understand technical solution of the present invention, and constitutes part of specification, with this
The embodiment of application technical solution for explaining the present invention together, does not constitute the limitation to technical solution of the present invention.
Fig. 1 is the flow chart of clock synchronizing method of the embodiment of the present invention；
Fig. 2 is a kind of structure composition schematic diagram of equipment of the embodiment of the present invention；
Fig. 3 is the structure composition schematic diagram of another kind of embodiment of the present invention equipment；
Fig. 4 is the structure composition schematic diagram of another equipment of the embodiment of the present invention.
Specific embodiment
The embodiment of the present invention is described in detail below in conjunction with attached drawing.It should be noted that not conflicting
In the case of, the features in the embodiments and the embodiments of the present application can mutual any combination.
Step shown in the flowchart of the accompanying drawings can be in a computer system such as a set of computer executable instructions
It executes.Also, although logical order is shown in flow charts, and it in some cases, can be to be different from herein suitable
Sequence executes shown or described step.
Referring to Fig. 1, the embodiment of the present invention proposes a kind of clock synchronizing method, comprising:
When upstream equipment where equipment and upstream clock where step 100, local clock connects, when the port of equipment
Clock status is from clock or only to do from clock, and when the port clock state of upstream equipment is master clock, equipment is set from upstream
It is standby to obtain and record for synchronous clock information.
In this step, clock information includes for determining a group or more of for synchronous timestamp of time difference；
When link delay mechanism is latency request-response mechanism, each group of timestamp includes: that upstream equipment sends the
The timestamp of one event message, upstream equipment receive the timestamp of second event message, equipment receive first event message when
Between stamp and equipment send second event message timestamp；
When link delay mechanism is reciprocity delay strategy, each group of timestamp includes: that upstream equipment sends first event
Timestamp, the upstream equipment of message receive the timestamp of second event message, and upstream equipment sends the time of third event message
Stamp, equipment receives the timestamp of first event message, equipment sends the timestamp of second event message and equipment receives third thing
The timestamp of part message.
Wherein, equipment receive first event message timestamp can when equipment receives first event message record,
The timestamp that equipment sends second event message can be recorded when equipment sends second event message, and equipment receives third event
The timestamp of message can when equipment receives third event message record.
The carrying that the timestamp that upstream equipment sends first event message can be sent from upstream equipment sends first event
It is obtained in the message of the timestamp of message, what the timestamp that upstream equipment receives second event message can be sent from upstream equipment
It carries and is obtained in the message for receiving the timestamp of second event message, the timestamp that upstream equipment sends third event message can be with
It is obtained in the message for the timestamp for sending third event message from the carrying that upstream equipment is sent.
Local clock is synchronized to upstream clock according to clock information by step 101.It specifically includes:
Step 1011: the corresponding head of this group of timestamp is determined and recorded based on the corresponding synchronization time difference of each group of timestamp
Secondary correction time is poor；
Wherein it is possible to determine according to the following formula:
Wherein, Fi is the corresponding correction time offseti for the first time of i-th group of timestamp
For i-th of time difference according to determined by i-th group of timestamp.
More specifically, since time synchronization process generallys use latency request-response mechanism and reciprocity delay strategy, root
It is as described below come the method for determining correction time for the first time according to two kinds of mechanism:
(1) when link delay mechanism is latency request-response mechanism,
Determine the corresponding link delay delay of each group of timestamp, specifically:
According to formulaCalculate the corresponding link delay of i-th group of timestamp；
Wherein, i is the integer more than or equal to 1；
The corresponding time difference offset of each group of timestamp is determined according to the corresponding link delay of each group of timestamp, specifically
Are as follows:
I-th group of timestamp corresponding time difference is calculated according to formula offseti=(ti2-ti1)-delayi；
The corresponding difference F of correction time for the first time of each group of timestamp is determined according to each group of timestamp corresponding time difference, is had
Body are as follows::
When i is 1, it is poor that the 1st group of timestamp corresponding correction time for the first time is calculated according to formula F 1=offset1；
When i is greater than or equal to 2, according to formulaIt is corresponding to calculate i-th group of timestamp
Correction time is poor for the first time；
Wherein, delayi is the corresponding link delay of i-th group of timestamp, and ti2 is that equipment receives first in i-th group of timestamp
The timestamp of event message, ti1 are the timestamp that i-th group of timestamp middle and upper reaches equipment sends first event message, ti3 i-th
Equipment sends the timestamp of second event message in group timestamp, and ti4 is that i-th group of timestamp middle and upper reaches equipment receives second event
The timestamp of message, offseti are i-th group of timestamp corresponding time difference, and F1 is the corresponding timing for the first time of the 1st group of timestamp
Between it is poor, Fi be i-th group of timestamp corresponding correction time for the first time it is poor, F (i-1) be (i-1) organize timestamp it is corresponding for the first time
Correction time is poor.
(2) when link delay mechanism is reciprocity delay strategy
Determine the corresponding link delay delay of each group of timestamp, specifically:
According to formulaCalculate the corresponding link delay of i-th group of timestamp；
Wherein, i is the integer more than or equal to 1；
The corresponding time difference offset of each group of timestamp is calculated according to the corresponding link delay of each group of timestamp, specifically
Are as follows:
I-th group of timestamp corresponding time difference is calculated according to formula offseti=(ti2-ti1)-delayi；
Equipment calculates the corresponding difference F of correction time for the first time of each group of timestamp according to link delay and time difference, specifically
Are as follows::
When i is 1, it is poor that the 1st group of timestamp corresponding correction time for the first time is calculated according to formula F 1=offset1；
When i is greater than or equal to 2, according to formulaIt is corresponding to calculate i-th group of timestamp
Correction time is poor for the first time；
Wherein, delayi is the corresponding link delay of i-th group of timestamp, and ti2 is that equipment receives first in i-th group of timestamp
The timestamp of event message, ti1 are the timestamp that i-th group of timestamp middle and upper reaches equipment sends first event message, ti3 i-th
Equipment sends the timestamp of second event message in group timestamp, and ti4 is that i-th group of timestamp middle and upper reaches equipment receives second event
The timestamp of message, ti5 is the timestamp that i-th group of timestamp middle and upper reaches equipment sends third event message, when ti6 is i-th group
Between stamp in equipment receive third event message timestamp, offseti be i-th group of timestamp corresponding time difference, F1 be the 1st group
Timestamp corresponding correction time for the first time is poor, and Fi is that i-th group of timestamp corresponding correction time for the first time is poor, and F (i-1) is the
(i-1) group timestamp corresponding correction time for the first time is poor.
Certainly, in other examples, when correction time difference F is also possible to directly take the synchronization of every group of timestamp for the first time
Between difference offset, without dealing with, but its synchronization accuracy will be determined not as good as referring to the synchronization time difference of upper one group of timestamp
Correction time for the first time it is poor；
Step 1012: determining and recording frequency of the every group of timestamp relative to first group of timestamp in each first preset time
Inclined correcting value；
The first preset time herein is to obtain the period of secondary correction time；Usually first preset time can be with
It is set as definite value, but in certain special situations, the first preset time be can be set to according to given value or rule variation
Period time value, do not limit herein；
Determine that every group of timestamp can lead to relative to the frequency offset correction amount of first group of timestamp in each first preset time
Cross following manner:
According to formula
Fi=(ti2-t12)-(ti1-t11) determines that i-th group of timestamp is relative to first group of time in the first preset time
The frequency offset correction amount of stamp；Wherein, i is integer more than or equal to 1, fi be in the first preset time i-th group of timestamp relative to
The frequency offset correction amount of first group of timestamp, ti2 be received in i-th group of timestamp in the first preset time first event message when
Between stab, t12 is the timestamp for receiving first event message in the first preset time in the 1st group of timestamp, when ti1 is first default
Interior i-th group of timestamp middle and upper reaches equipment sends the timestamp of first event message, when t11 is the 1st group in the first preset time
Between stamp middle and upper reaches equipment send first event message timestamp.
As fi=0, indicate synchronous with master clock frequency from clock；
As fi > 0, indicate fast from clock ratio master clock frequency；
As fi < 0, indicate slow from clock ratio master clock frequency.
Optionally, as fi=0, the value can be no longer calculated in first preset time, and is defaulted and originally first preset
It is synchronous with master clock frequency from clock in time, or optionally, as fi=0, multiple first preset times can be spaced and taken
Value calculates whether f is 0 again, with monitoring from clock and master clock whether Frequency Synchronization, think during this from clock and it is main when
Clock is synchronous；
It in another embodiment, for simplicity, can be in the first preset time just for every m group time
Stamp group calculate the primary m group timestamp relative to first group of timestamp frequency offset correction amount (calculation method with it is upper similar, no longer
Repeat), and using the result of the secondary frequency offset calculation amount as by other groups of timestamps in first preset time relative to first
Group timestamp frequency offset correction amount, typically, can by last group of timestamp in the first preset time relative to first group when
Between the frequency offset correction amount stabbed as frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the predetermined time, thus
Simplify calculating process, this can generally be influenced to change in little scene application by the external world in amounts of frequency offset realizes.
Step 1013: being carried out using for the first time correction time difference of the frequency offset correction amount obtained to corresponding this group of timestamp
Secondary correction obtains and records this group of timestamp corresponding secondary correction time difference；
Specifically, calculating the corresponding secondary school of i-th group of timestamp in the first preset time according to formula CorFi=Fi-fi
The positive time difference；
Wherein i is the integer more than or equal to 1, and CorFi is the corresponding secondary school of i-th group of timestamp in the first preset time
Positive time difference, Fi are that i-th group of timestamp corresponding correction time for the first time of acquisition in the first preset time is poor, and fi is first default
The corresponding frequency offset correction amount of i-th group of timestamp in time.
Step 1014: every the second preset time according to the last one the secondary correction time obtained in the second preset time
It is synchronous that difference carries out clock to local clock.
Wherein, the second preset time is period synchronization time of identified equipment in advance, in second preset time
One group of acquisition or multiple groups can be set according to system for synchronous timestamp, do not limited herein.
Optionally, big when a certain group of timestamp corresponding secondary correction time difference for judging to obtain in the second preset time
When time difference threshold value, it is synchronous that clock is carried out according to this group of timestamp corresponding secondary correction time difference.
Wherein, time difference threshold value can obtain knowing and being manually set by test of many times.
Step 102, when equipment and upstream equipment disconnect suddenly, according to recorded in synchronizing process for it is synchronous when
Clock information is modified compensation to local clock.
It, can be by judging whether third preset time has more newly arriving for clock information of progress to judge that equipment is in this step
It is no to disconnect with upstream equipment, when the update for judging not having to carry out clock information in third preset time, judge equipment with
Upstream equipment disconnects；When judging has the update for carrying out clock information in third preset time, judge that equipment is set with upstream
It is standby to be not turned off.
In this step, after being disconnected due to equipment and upstream equipment, local clock is usually to continue to tie up by local crystal oscillator
Hold the time, it is assumed that the function model of clock is T (t)=wt+ β, wherein t is the reference time, and w is that instantaneous moment clock frequency is inclined
Difference, β are phase deviation, when due to carrying out having had recorded every group during clock is synchronous when equipment is connected with upstream equipment
Between the difference Fi of correction time for the first time, the frequency offset correction amount fi that stab, according to the clock information recorded in synchronizing process to local clock into
Row correction-compensation includes:
According to formula:
Compensation is modified to local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first first default
The corresponding frequency offset correction amount of m1 group timestamp in time, f (m2/T2) are m2 group timestamp in the 2nd the first preset time
Corresponding frequency offset correction amount ... ..., f (mn/Tn) are the corresponding frequency offset correction of mn group timestamp in n-th of first preset times
Amount, T1 are the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F
(m1/T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd
M2 group timestamp corresponding correction time for the first time is poor in first preset time ... ..., F (mn/Tn) be n-th first it is default when
In mn group timestamp corresponding correction time for the first time it is poor, n is the integer more than or equal to 1；And the selection of m group timestamp
(selection of m1, m2 ... ... mn) can be determined according to preset rule, for example, all selecting in the first preset time
The timestamp of same sequence number, but if the first preset time value is different, the selective value of m group timestamp be can also be different,
It preferably can all directly select as last group of timestamp in the current first choice time.
By above-mentioned clock compensation method, it can make equipment after disconnecting with upstream clock, with the maintenance of local crystal oscillator
In the case where local clock, it still is able to historical time information pair recorded in the synchronizing process according to before with upstream clock
Local zone time compensates, since the compensating approach is to be based on original upstream clock and local clock, using the method
Local clock can be made to remain in certain accuracy rating the synchronization time after disconnecting with upstream clock.
Optionally, when the precision of the crystal oscillator frequency of local clock is higher, typically, when being higher than predetermined value (4.6ppm),
Equipment every third preset time according to the secondary correction time difference obtained in synchronizing process with the sequence of inverted order to local clock
It is modified compensation, when third preset time herein carries out the setting that local zone time synchronizes when can be a disconnection of setting
Between, but preferably, which can be synchronization time when equipment normally connects upstream equipment (for example, second
Preset time)；Thereby guarantee that equipment line with disconnect when synchronization time it is consistent.
That is, in first third preset time, it is corresponding according to last group of timestamp obtained in synchronizing process
The secondary correction time difference compensation is modified to local clock；In second third preset time, obtained according in synchronizing process
The second from the bottom group of timestamp corresponding secondary correction time difference obtained is modified compensation to local clock；..., at n-th
Three preset times, according to the n-th group timestamp reciprocal corresponding secondary correction time difference obtained in synchronizing process to local clock
It is modified compensation.
Optionally, this method further include:
After equipment and upstream equipment restore connection, equipment continues to execute the port clock state when equipment as from clock or only
It does from clock, and when the port clock state of upstream equipment is master clock, equipment obtains clock information from upstream equipment, according to obtaining
The step of local clock is synchronized to upstream clock by the clock information obtained.
Referring to fig. 2, the embodiment of the present invention also proposed a kind of equipment, comprising:
Obtain module, when for connect with the upstream equipment where upstream clock, when port clock state for from clock or
It only does from clock, and when the port clock state of upstream equipment is master clock, obtains and recorded for synchronization from upstream equipment
Clock information；
Synchronization module, for local clock to be synchronized to upstream clock according to clock information；
Compensating module, for when being disconnected suddenly with upstream equipment, the clock information pair according to recorded in synchronizing process
Local clock is modified compensation.
Optionally, clock information includes for determining a group or more of for synchronous timestamp of time difference；
The synchronization module is specifically used for:
Determine and record that this group of timestamp corresponding correction time for the first time is poor based on each group of timestamp corresponding time difference；
Determine and record frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the first preset time, and benefit
Secondary correction is carried out to the corresponding difference of correction time for the first time of each group of timestamp with frequency offset correction amount obtained, obtains and records
This group of timestamp corresponding secondary correction time difference；
Every the second preset time according to the last one the secondary correction time difference pair obtained in second preset time
It is synchronous that local clock carries out clock.
Optionally, the compensating module is specifically used for:
When being disconnected suddenly with upstream equipment,
According to formula
Compensation is modified to the local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first first default
The corresponding frequency offset correction amount of m1 group timestamp in time, f (m2/T2) are m2 group timestamp in the 2nd the first preset time
Corresponding frequency offset correction amount ... ..., f (mn/Tn) are the corresponding frequency offset correction of mn group timestamp in n-th of first preset times
Amount, T1 are the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F
(m1/T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd
M2 group timestamp corresponding correction time for the first time is poor in first preset time ... ..., F (mn/Tn) be n-th first it is default when
In mn group timestamp corresponding correction time for the first time it is poor, n is the integer more than or equal to 1.
Referring to Fig. 3, as an example, the equipment of the embodiment of the present invention includes:
The port PTP is from clock or only to do from clock for the port clock state when the port PTP, and upstream equipment
When the port clock state of the port PTP is master clock, clock information is obtained from upstream equipment；
Best master clock module, for recording the clock information obtained；
Clock synchronization module is calibrated, for local clock to be synchronized to upstream clock according to clock information；When prominent with upstream equipment
When so disconnecting, the clock information according to recorded in synchronizing process is modified compensation to local clock.
Optionally, clock information includes for determining a group or more of for synchronous timestamp of time difference；
Calibration clock synchronization module, which is specifically used for realizing in the following ways, is synchronized to upstream for local clock according to clock information
Clock includes:
Determine and record that this group of timestamp corresponding correction time for the first time is poor based on each group of timestamp corresponding time difference；
Determine and record frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the first preset time, and benefit
Secondary correction is carried out to the corresponding difference of correction time for the first time of each group of timestamp with frequency offset correction amount obtained, obtains and records
This group of timestamp corresponding secondary correction time difference；
Every the second preset time according to the last one the secondary correction time difference pair obtained in second preset time
It is synchronous that local clock carries out clock.
Optionally, equipment further include:
Global data collection, for saving link delay mechanism；
The port PTP is specifically used for:
When link delay mechanism is latency request-response mechanism, the of the port PTP from upstream equipment is received
The port PTP of one event message, upstream device sends second event message；Receive the port PTP from upstream equipment
Message comprising sending the message of the timestamp of first event message and the timestamp of reception second event message；
When link delay mechanism is reciprocity delay strategy, the first event of the port PTP from upstream equipment is received
The port PTP of message, upstream device sends second event message；Receive the third thing of the port PTP from upstream equipment
Part message；Receive the message of the timestamp of the carrying transmission first event message of the port PTP from upstream equipment, carrying connects
It receives the message of the timestamp of second event message and carries the message for sending the timestamp of third event message；
Best master clock module is specifically used for:
When link delay mechanism is latency request-response mechanism, when the port PTP receives first event message, note
Record receives the timestamp of first event message；
When the port PTP sends second event message, record sends the timestamp of second event message；
When the port PTP receives the message comprising the timestamp for sending first event message, the transmission in message is obtained
The timestamp and record of first event message；
When the port PTP receives the message comprising the timestamp for receiving second event message, the reception in message is obtained
The timestamp and record of second event message.
When link delay mechanism is reciprocity delay strategy, when the port PTP receives first event message, record is received
To the timestamp of first event message；
When the port PTP sends second event message, record sends the timestamp of second event message；
When the port PTP receives third event message, record receives the timestamp of third event message；
When the port PTP receives the message comprising the timestamp for sending first event message, the transmission in message is obtained
The timestamp and record of first event message；
When the port PTP receives the message comprising the timestamp for receiving second event message, the reception in message is obtained
The timestamp and record of second event message；
When the port PTP receives the message comprising the timestamp for sending third event message, the transmission in message is obtained
The timestamp and record of third event message.
Referring to fig. 4, the embodiment of the present invention also proposed a kind of equipment, comprising:
The port Precision Time Protocol PTP, processor and computer readable storage medium；
The port PTP, for obtaining clock information from upstream equipment；
It is stored with instruction in the computer readable storage medium, when described instruction is executed by the processor, realizes
Following steps:
When being connect with the upstream equipment where upstream clock, when the port clock state of the port PTP is from clock or only to do
From clock, and when the port clock state of the port PTP of upstream equipment is master clock, the control port PTP is obtained from upstream equipment
Clock information, and recording clock information；
Local clock is synchronized to upstream clock according to the clock information of acquisition；
When disconnecting suddenly with upstream equipment, the clock information according to recorded in synchronizing process repairs local clock
Positive compensation.
Although disclosed herein embodiment it is as above, the content only for ease of understanding the present invention and use
Embodiment is not intended to limit the invention.Technical staff in any fields of the present invention is taken off not departing from the present invention
Under the premise of the spirit and scope of dew, any modification and variation, but the present invention can be carried out in the form and details of implementation
Scope of patent protection, still should be subject to the scope of the claims as defined in the appended claims.
Claims (11)
1. a kind of clock synchronizing method characterized by comprising
Where equipment and upstream clock where local clock upstream equipment connection when, when equipment port clock state be from
Clock is only done from clock, and when the port clock state of upstream equipment is master clock, equipment is obtained and recorded from upstream equipment
Local clock is synchronized to upstream clock for synchronous clock information, and according to the clock information；
When equipment and upstream equipment disconnect suddenly, the clock information according to recorded in synchronizing process is modified local clock
Compensation；
Wherein, the clock information includes for determining a group or more of for synchronous timestamp of time difference；
Local clock, which is synchronized to upstream clock, according to the clock information includes:
Determine and record that this group of timestamp corresponding correction time for the first time is poor based on each group of timestamp corresponding time difference；
It determines and records frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the first preset time, and utilizes institute
The frequency offset correction amount of acquisition carries out secondary correction to the corresponding difference of correction time for the first time of each group of timestamp, obtains and records the group
The timestamp corresponding secondary correction time difference；
Every the second preset time according to the last one the secondary correction time difference obtained in second preset time to local
It is synchronous that clock carries out clock.
2. clock synchronizing method according to claim 1, which is characterized in that
It is described to determine that the corresponding difference of correction time for the first time of this group of timestamp includes: based on each group of timestamp corresponding time difference
Wherein, Fi is that i-th group of timestamp corresponding correction time for the first time is poor, offseti
For i-th of time difference according to determined by i-th group of timestamp.
3. clock synchronizing method according to claim 1, which is characterized in that the secondary correction time difference passes through with lower section
Formula obtains:
Every group of timestamp includes: by first relative to the frequency offset correction amount of first group of timestamp in first preset time of determination
One group of timestamp of setting is relative to the frequency offset correction amount of first group of timestamp as in first predetermined time in preset time
Frequency offset correction amount of the every group of timestamp relative to first group of timestamp.
4. clock synchronizing method according to claim 1, which is characterized in that this method comprises:
When a certain group of timestamp corresponding secondary correction time difference is greater than preset time difference threshold value in second preset time
When, it is synchronous that clock is carried out according to a certain group of timestamp corresponding secondary correction time difference.
5. clock synchronizing method according to claim 1, which is characterized in that
Every group of timestamp includes: relative to the frequency offset correction amount of first group of timestamp in first preset time of determination
Determine that i-th group of timestamp is relative to first group in the first preset time according to formula fi=(ti2-t12)-(ti1-t11)
The frequency offset correction amount of timestamp；Wherein, i is the integer more than or equal to 1, and fi is i-th group of timestamp phase in the first preset time
For the frequency offset correction amount of first group of timestamp, ti2 is to receive first event message in the first preset time in i-th group of timestamp
Timestamp, t12 is the timestamp for receiving first event message in the first preset time in the 1st group of timestamp, and ti1 is first pre-
If i-th group of timestamp middle and upper reaches equipment sends the timestamp of first event message in the time, t11 is the 1st in the first preset time
Group timestamp middle and upper reaches equipment sends the timestamp of first event message.
6. clock synchronizing method according to claim 1, which is characterized in that
It is described to carry out secondary correction using for the first time correction time difference of the frequency offset correction amount obtained to corresponding timestamp, it obtains
This group of timestamp corresponding secondary correction time difference includes:
I-th group of timestamp corresponding secondary correction time difference in the first preset time is calculated according to formula CorFi=Fi-fi；
Wherein i is integer more than or equal to 1, when CorFi is the corresponding secondary correction of i-th group of timestamp in the first preset time
Between it is poor, Fi be the first preset time in obtain i-th group of timestamp corresponding correction time for the first time it is poor, fi be the first preset time
The corresponding frequency offset correction amount of interior i-th group of timestamp.
7. clock synchronizing method according to claim 1, which is characterized in that
Clock information recorded in the synchronizing process includes: that the correction time for the first time of every group of timestamp is poor, frequency offset correction amount,
The clock information according to recorded in synchronizing process is modified compensation to local clock and includes:
According to formula
Compensation is modified to the local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first the first preset time
The corresponding frequency offset correction amount of interior m1 group timestamp, f (m2/T2) are m2 group timestamp correspondence in the 2nd the first preset time
Frequency offset correction amount ... ..., f (mn/Tn) is the corresponding frequency offset correction amount of mn group timestamp in n-th first preset times,
T1 is the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F (m1/
T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd first
M2 group timestamp corresponding correction time for the first time is poor in preset time ... ..., and F (mn/Tn) is in n-th of first preset times
Mn group timestamp corresponding correction time for the first time is poor, and n is the integer more than or equal to 1.
8. clock synchronizing method according to claim 1, which is characterized in that
Clock information recorded in the synchronizing process include: the correction time for the first time of every group of timestamp is poor, frequency correction amount with
And secondary correction time value,
The clock information according to recorded in synchronizing process is modified compensation to local clock and includes:
It is each according to what is obtained in synchronizing process every third preset time when the precision of local clock crystal oscillator is higher than predetermined value
The group timestamp corresponding secondary correction time difference, compensation is modified to the local clock with the sequence of inverted order；
Otherwise, according to formula
Compensation is modified to the local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first the first preset time
The corresponding frequency offset correction amount of interior m1 group timestamp, f (m2/T2) are m2 group timestamp correspondence in the 2nd the first preset time
Frequency offset correction amount ... ..., f (mn/Tn) is the corresponding frequency offset correction amount of mn group timestamp in n-th first preset times,
T1 is the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F (m1/
T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd first
M2 group timestamp corresponding correction time for the first time is poor in preset time ... ..., and F (mn/Tn) is in n-th of first preset times
Mn group timestamp corresponding correction time for the first time is poor, and n is the integer more than or equal to 1.
9. a kind of clock synchronization device characterized by comprising
Module is obtained, when for connect with the upstream equipment where upstream clock, when port clock state is from clock or only does
From clock, and when the port clock state of upstream equipment is master clock, is obtained from upstream equipment and record the clock for synchronization
Information；
Synchronization module, for local clock to be synchronized to upstream clock according to clock information；
Compensating module, for when disconnecting suddenly with upstream equipment, the clock information according to recorded in synchronizing process to be to local
Clock is modified compensation；
Wherein, the clock information includes for determining a group or more of for synchronous timestamp of time difference；
The synchronization module is specifically used for:
Determine and record that this group of timestamp corresponding correction time for the first time is poor based on each group of timestamp corresponding time difference；
It determines and records frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the first preset time, and utilizes institute
The frequency offset correction amount of acquisition carries out secondary correction to the corresponding difference of correction time for the first time of each group of timestamp, obtains and records the group
The timestamp corresponding secondary correction time difference；
Every the second preset time according to the last one the secondary correction time difference obtained in second preset time to local
It is synchronous that clock carries out clock.
10. equipment according to claim 9, which is characterized in that the compensating module is specifically used for:
When being disconnected suddenly with upstream equipment,
According to formula
Compensation is modified to the local clock；
Wherein, T (t) is the correction-compensation amount of local clock, and t is the reference time, and f (m1/T1) is first the first preset time
The corresponding frequency offset correction amount of interior m1 group timestamp, f (m2/T2) are m2 group timestamp correspondence in the 2nd the first preset time
Frequency offset correction amount ... ..., f (mn/Tn) is the corresponding frequency offset correction amount of mn group timestamp in n-th first preset times,
T1 is the 1st the first preset time, and T2 is the 2nd the first preset time ... ..., and Tn is n-th of first preset times, F (m1/
T1) poor for m1 group timestamp corresponding correction time for the first time in the 1st the first preset time, F (m2/T2) is the 2nd first
M2 group timestamp corresponding correction time for the first time is poor in preset time ... ..., and F (mn/Tn) is in n-th of first preset times
Mn group timestamp corresponding correction time for the first time is poor, and n is the integer more than or equal to 1.
11. a kind of clock synchronization device characterized by comprising the port Precision Time Protocol PTP, processor and computer can
Read storage medium；
The port PTP, for obtaining clock information from upstream equipment；
It is stored with instruction in the computer readable storage medium, when described instruction is executed by the processor, realizes as follows
Step:
When being connect with the upstream equipment where upstream clock, when the port clock state of the port PTP be from clock or only do from when
Clock, and the port clock state of the port PTP of upstream equipment be master clock when, control the port PTP from upstream equipment acquisition be used for
Synchronous clock information, and recording clock information；
Local clock is synchronized to upstream clock according to clock information；
When disconnecting suddenly with upstream equipment, the clock information according to recorded in synchronizing process is modified benefit to local clock
It repays；
Wherein, the clock information includes for determining a group or more of for synchronous timestamp of time difference；
Local clock, which is synchronized to upstream clock, according to the clock information includes:
Determine and record that this group of timestamp corresponding correction time for the first time is poor based on each group of timestamp corresponding time difference；
It determines and records frequency offset correction amount of the every group of timestamp relative to first group of timestamp in the first preset time, and utilizes institute
The frequency offset correction amount of acquisition carries out secondary correction to the corresponding difference of correction time for the first time of each group of timestamp, obtains and records the group
The timestamp corresponding secondary correction time difference；
Every the second preset time according to the last one the secondary correction time difference obtained in second preset time to local
It is synchronous that clock carries out clock.
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| EP4120588A4 (en) | 2020-03-30 | 2023-04-12 | Huawei Technologies Co., Ltd. | Data processing method and apparatus |
| CN114765635B (en) * | 2021-01-08 | 2024-02-20 | 腾讯科技（深圳）有限公司 | Clock synchronization method, device, system, computer equipment and storage medium |
| CN115459871A (en) * | 2021-06-08 | 2022-12-09 | 中兴通讯股份有限公司 | Time synchronization method, network device and storage medium |
| CN114006674B (en) * | 2021-12-31 | 2022-04-01 | 深圳市海清视讯科技有限公司 | Time correction method, device, equipment and storage medium for attendance equipment |
| CN117155499A (en) * | 2022-05-24 | 2023-12-01 | 华为技术有限公司 | Clock synchronization method, serial number generation method and device |
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