CN100373828C - Method for testing clock reverse delay system of transmission equipment - Google Patents
Method for testing clock reverse delay system of transmission equipment Download PDFInfo
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- CN100373828C CN100373828C CNB021525307A CN02152530A CN100373828C CN 100373828 C CN100373828 C CN 100373828C CN B021525307 A CNB021525307 A CN B021525307A CN 02152530 A CN02152530 A CN 02152530A CN 100373828 C CN100373828 C CN 100373828C
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Abstract
The present invention relates to a test method of a clock reverse delay system of a transmission device. The method comprises the following steps that 1, N network units are orderly connected into a long chain, wherein N is not less than 2; 2, the working mode, the clock priority, the clock ID and the clock source quality of the network units are reasonably allocated according to a reverse delay kind to be tested; 3, the external clock information of the first network unit is correspondingly input, changed and operated according to the reverse delay kind to be tested; some network units obtain corresponding warning time; 4, two warning times are taken out to calculate a difference value T according to the reverse delay kind to be tested and the number K of the finished corresponding reverse delay kind in the two warning times are also calculated; then, the average value T/K of the reverse delay kind can be obtained. The present invention solves the technical problem that the existing method for testing the reverse delay in the working mode of clock synchronization information needs a time interval analyzer to test.
Description
Technical field
The present invention relates to the method for testing of transmission equipment, relate in particular to a kind of method of testing of transmission equipment clock switch delayed time system.
Prior art
The clock work pattern of existing transmission equipment is divided into two kinds:
First kind is clock work pattern according to priority, and the optional clock of this mode of operation sorts by priority and priority list, and the foundation that equipment is followed the tracks of clock is: existence and clock source that priority is the highest.
Second kind is clock synchronization information (SSM) mode of operation, this mode of operation also has the priority list of a clock, each clock also has the clock sign in addition, clock quality information (is represented with S1 byte, be referred to as the SSM quality), the foundation that equipment is followed the tracks of clock is: the clock sign is arranged, and clock quality is the highest and be present in the clock priority table; Network element device can be broadcasted away the sign and the quality information of the clock of current tracking by light path.
In above-mentioned two kinds of mode of operations, the classification in clock source mainly contains:
1 external clock reference (abbreviation external source): network element has two external clock source interfaces, can obtain clock signal from outside BITS (a kind of equipment that clock signal is provided specially), we are referred to as external clock reference this clock signal that obtains from the external clock interface.
2 line clock sources: network element device extracts clock signal and uses to equipment from the light signal that enters network element device, and this is exactly the line clock source.Line source has can be had a plurality ofly, and how much optical fiber depends on has be linked into network element device.
3 inside sources, when the external source in the priority list and line source were all invalid, the crystal oscillator that network element is examined network element internal oneself provided clock signal to use to equipment, and this is that the clock source is exactly the network element internal clock; Inside sources has only one.
At second kind of clock work pattern, the G.781 agreement of International Telecommunications Union has been made detailed regulation for the time delay of switching in the SSM process, mainly contains to keep information delay T
HM(Holdover Message Delay), non-switch messages time-delay T
NSM(Non-switching message delay) and switch messages time-delay T
SM(Switching messagedelay).
Maintenance information prolong be meant when the clock source of the current tracking of network element device become invalid, and other clock sources are except the network element internal clock when all unavailable in the priority list, at this moment network element device can enter the maintenance pattern, the own internal clocking of network element clock tracing network element, and through after the time-delay, the quality information of internal clocking is broadcasted away, and this time-delay becomes the maintenance information delay; This delay time T
HMBe 300-2000ms.
Non-switch messages time-delay (T
NSM) be meant that the quality information when the clock source that network element device is followed the tracks of has changed, but still the time top-quality in priority list, become 0x04 such as clock quality by original 0x02, the clock source that network element is followed the tracks of can not change, that is to say that the clock source not switch, network element device can be broadcasted away along light path by the quality information (such as 0x04) that clock is new after through an of short duration time-delay, and this of short duration time-delay is delayed time non-switch messages; This delay time T
NSMBe 0-200ms.
Switch messages time-delay (T
SM) when being meant invalid that quality information when the clock source that network element device is followed the tracks of becomes, also with regard to the time clock quality information become 0xff, network element device can be followed the tracks of other top-quality clock sources in the priority list, and this process of following the tracks of new clock source again is the clock switch process just; Follow the tracks of after the new clock source, equipment can not broadcasted away the quality information in new clock source immediately, but to just the new quality information in new clock source be broadcasted away through after the of short duration time-delay, this time-delay is referred to as the switch messages time-delay; This delay time T
SMBe 180-500ms.
Existing the test of switching time-delay in clock synchronization information (SSM) mode of operation is tested by time interval analyzer, time interval analyzer is followed the tracks of the output clock of network element, when network element clock source clock changes, clock phase has a big transition, tend towards stability then, according to the accurately testing time time-delay of switching of the variation of phase place.Though this kind technology can be switched the test of time-delay the time of satisfying, it needs special test instrumentation, so have testing cost height, the relatively poor shortcoming of test all-purpose.
Summary of the invention
The method of testing of a kind of transmission equipment clock switch delayed time system provided by the invention can solve the problem of in the prior art being switched the special test instrumentation of test needs of time-delay the time.
In order to solve above technical problem, the technical scheme that the present invention takes is:
A kind of method of testing of transmission equipment clock switch delayed time system is characterized in that, this method may further comprise the steps:
(1) N network element connected into a long-chain in regular turn, N is not less than 2;
(2) kind of switching time-delay of testing according to need, the sign of the clock synchronization information mode of operation of each network element of reasonable disposition, clock priority, clock and the quality in clock source;
(3) according to the kind of switching time-delay of need test, corresponding input or the external clock information and the operation of changing first network element; Obtain the corresponding alarm time of some network elements;
(4) kind of switching time-delay of testing according to need, take out two alarm times wherein, calculate in the difference T of these two alarm times and these two alarm times and finish the number K that corresponding kind is switched time-delay, can draw the mean value T/K that such switches time-delay, such mean value T/K that switches time-delay is considered as the value that such switches time-delay.
When maintenance information delay in the delayed time system was switched in test, the mode of operation of each network element was configured to clock synchronization information (SSM) in the described step (two); First network element clock priority is configured to follow the tracks of external clock and network element internal clock, and the internal clocking sign of first network element will not dispose; The clock priority of N-1 network element after the first network element is configured to follow the tracks of line clock and network element internal clock; Input in the described step (three) before the operation or the external clock information that changes first network element are the disconnecting external clock.
When maintenance information delay in the delayed time system was switched in test, the mode of operation of each network element was configured to clock synchronization information (SSM) in the described step (two); The clock priority of N-1 network element after the first network element is configured to follow the tracks of line clock and network element internal clock; Being configured to of the internal clocking quality of each network element increased in regular turn; Input in the described step (three) before the operation or the external clock information that changes first network element are the disconnecting external clock.
When non-switch messages time-delay in the delayed time system was switched in test, the N in the described step () was not less than 3, and the mode of operation of each network element is configured to clock synchronization information (SSM) in the described step (two); First network element clock priority is configured to follow the tracks of external clock and network element internal clock, and the external clock quality of first network element is configured to be higher than the network element internal clock quality of first network element; N-1 network element priority after the first network element is configured to follow the tracks of line clock and network element internal clock; N-2 network element internal clock quality after the first network element before last network element is configured to all be lower than the network element internal clock quality of first network element, and the internal clocking quality of last network element is configured to be higher than first network element internal clock quality; Input in the described step (three) before the operation or the external clock information that changes first network element are for changing to the quality of external clock the quality of the internal clocking that is lower than first network element.
Switch switch messages when time-delay in the delayed time system when test, the mode of operation of each network element is configured to clock synchronization information (SSM) in the described step (two); First network element clock priority is configured to an outside clock, outside two clocks and network element internal clock, the quality of outside one clock of first network element is lower than the quality of network element internal clock, and the quality of outside two clocks is configured to be not less than the quality of its network element internal clock; N-1 network element priority after the first network element is configured to follow the tracks of line clock, external clock and network element internal clock; The external clock quality that the quality of N-1 network element after the first network element is configured to each network element is higher than the quality that it is followed the tracks of the quality of line clock and is not less than its internal clocking, and input in the described step (three) before the operation or the external clock information that changes first network element change to the quality that is not less than outside two clocks for the quality with an outside clock and is not less than the external clock quality of first network element N-1 network element afterwards.
The external clock of N-1 network element after outside two clocks of described first network element and the first network element can substitute with the line clock two of same quality.
After having adopted technique scheme, because the number of times of switching time-delay according to the corresponding kind of finishing in the difference of two alarm times and two alarm times can calculate the time-delay of switching of corresponding kind, thereby has solved the technical problem that time-delay needs time interval analyzer to test of switching in existing test clock synchronizing information (SSM) mode of operation.
Description of drawings
Fig. 1 is overall flow figure of the present invention.
Fig. 2 utilizes the present invention to test the flow chart that keeps information delay in the time-delay of transmission equipment clock switch.
Fig. 3 utilizes the present invention to test the flow chart of non-switch messages time-delay in the time-delay of transmission equipment clock switch.
Fig. 4 utilizes the present invention to test the flow chart of switch messages time-delay in the time-delay of transmission equipment clock switch.
Embodiment
Embodiment one
As shown in Figure 2, keep the method for testing of information delay in a kind of transmission equipment clock switch time-delay, can be implemented as follows:
(1) 20 network elements is connected into a long-chain in regular turn;
(2) mode of operation with each network element is configured to clock synchronization information (SSM); First network element clock priority is configured to follow the tracks of external clock and network element internal clock, and the external clock quality information is 0x02, and the internal clocking sign of first network element will not dispose; The configuring external clock is designated 1; The clock priority of 19 network elements after the first network element is configured to follow the tracks of line clock and network element internal clock;
(3) disconnecting external clock, 1 to No. 20 network element all obtain alarm time separately;
(4) taking-up two alarm times wherein, calculate and finish the number K that keeps information delay in the difference T of these two alarm times and these two alarm times, can draw the mean value T/K that keeps information delay, the mean value T/K that keeps information delay is considered as keeping the value of information delay.
When No. 1 network element external source disconnected, only remaining network element internal clock can be used in No. 1 network element priority list, so the clock source is switched to inside sources from external source, can interrupt reporting the LTI alarm simultaneously; No. 1 network element can be broadcast to network element No. 2 along light path with the quality information in No. 1 network element internal clock source after one of experience keeps information delay.But because No. 1 network element internal clock source does not have the configurable clock generator sign, so No. 2 network element only receives the clock quality that No. 1 network element broadcasting is come, but there is not the clock sign, it is invalid not having the clock source of clock sign, what promptly the line source of No. 2 network elements became is invalid, so No. 2 network elements are switched to inside sources; And the like No. 3 to No. 20 network elements also be switched to inside sources from line source successively, also interrupt reporting the LTI alarm up to No. 20 network elements, this process experiences 20 altogether and keeps information delays, that is to say that time difference that No. 1 network element and No. 20 network element LTI report is exactly 20 and keeps information delays.Therefore can test out the average maintenance information delay of product.
Certainly also can be in the step (two) in embodiment one, and the configuration of the internal clocking quality of 19 network elements after the first network element is increased in regular turn to the internal clocking configuration identifier of first network element, information delay so equally also can be maintained during the disconnecting external clock.
Embodiment two
As shown in Figure 3, the method for testing of non-switch messages time-delay in a kind of transmission equipment clock switch time-delay can be implemented as follows:
(1) 20 network elements is connected into a long-chain in regular turn;
(2) mode of operation with each network element is configured to clock synchronization information (SSM); First network element clock priority is configured to follow the tracks of external clock and network element internal clock, and the external clock quality information is 0x02, and the internal clocking quality information of first network element is 0x08, and the configuring external clock is designated 1; The clock priority of 19 network elements after the first network element is configured to follow the tracks of line clock and network element internal clock, and the internal clocking quality of middle 18 network elements is configured to 0x0b, and the internal clocking quality of last network element is configured to 0x04;
(3) the external clock quality of revising first network element is 0x08, and 1 to No. 20 network element all obtains alarm time separately;
(4) take out first and last alarm time, calculate the number 18 of finishing non-switch messages time-delay in the difference T of these two alarm times and these two alarm times, can draw the mean value T/18 of non-switch messages time-delay, the mean value T/K of non-switch messages time-delay is considered as the value of non-switch messages time-delay.
When the quality information of revising external clock reference is 0x0b, then be switched to inside sources from original external source No. 1, then can report clock switch alarm S1CHANGE and time, clock quality information (0x08) after then changing is broadcast to network element No. 2, No. 2 network element is broadcast to network element No. 3, so changing back clock quality information (0x08) transmits in 2～No. 19 network elements of whole piece chain, but does not switch in the clock source, to No. 20 network elements, the clock quality information (0x08) that receives is lower than clock quality information (0x04) quality of inside sources, so the clock source is switched to internal clock source, also interrupt report and alarm S1CHANGE and alarm time started.Be reported to No. 20 network element S1CHANGE to report from No. 1 network element S1CHANGE, the time of experience is 18 non-switch messages time-delays, just two alarm report time differences, therefore also can obtain non-switch messages time-delay.
Embodiment three
As shown in Figure 4, the method for testing of a kind of transmission equipment clock switch time-delay switch messages time-delay can be implemented as follows:
(1) 20 network elements is connected into a long-chain in regular turn;
(2) mode of operation with each network element is configured to clock synchronization information (SSM); First network element clock priority is configured to an outside clock, outside two clocks and network element internal clock, the quality of outside one clock of first network element is 0x08, the clock sign is 1, and the quality of outside two clocks is configured to 0x04, and the quality of first network element internal clock is configured to 0x04; 19 network element priority after the first network element are configured to follow the tracks of line clock, external clock and network element internal clock; The external clock quality of 19 network elements after the first network element is configured to 0x04, and clock is designated 2, and the internal clocking quality of 19 network elements after the first network element is configured to 0x04;
(3) the external clock quality of the first network element of modification is 0x02, obtains 1 to No. 20 network element alarm time separately;
(4) taking-up first and last alarm time wherein, calculate the number 19 of finishing the switch messages time-delay in the difference T of these two alarm times and these two alarm times, can draw the mean value T/19 of switch messages time-delay, the mean value T/19 of switch messages time-delay is considered as the value of switch messages time-delay.
When the clock quality of revising external clock reference is 0x02, the ratio line clock source quality information (0x04) that the external clock source quality (0x02) of No. 1 network element priority list becomes is better, so No. 1 network element clock switch is to external clock reference, and after switch messages time-delay of experience, this external source clock quality (0x02) and clock identification information are broadcast to network element No. 2, so No. 2 NE Discovery line clock quality informations (0x02) are better than original external clock quality (0x04) information, so also be switched to external clock; 3 to No. 20 network elements all are switched to the line clock source successively similarly, follow the tracks of the clock that external clock reference provides.This process, 1 to No. 20 each network element of network element all experiences a switch messages time-delay, just switch No. 20 network elements and switch end since No. 1 network element, experienced the time-delay of 19 switch messages altogether, promptly No. 1 network element is switched the time difference that beginning S1CHANGE alarm report time and No. 20 network element S1CHANGE report automatically.
Certainly, the external clock of 19 network elements after outside two clocks of first network element and the first network element can substitute with the line clock two of same quality in the step of embodiment three (two).
Claims (6)
1. the method for testing of a transmission equipment clock switch delayed time system is characterized in that, this method may further comprise the steps:
(1) N network element connected into a long-chain in regular turn, N is not less than 2;
(2) kind of switching time-delay of testing according to need, the sign of the clock synchronization information mode of operation of each network element of reasonable disposition, clock priority, clock and the quality in clock source;
(3) according to the kind of switching time-delay of need test, corresponding input or the external clock information and the operation of changing first network element; Obtain the corresponding alarm time of some network elements;
(4) kind of switching time-delay of testing according to need is taken out two alarm times wherein, calculate in the difference T of these two alarm times and these two alarm times and finish the number K that corresponding kind is switched time-delay, can draw the mean value T/K that such switches time-delay, such mean value T/K that switches time-delay is considered as the value that such switches time-delay.
2. the method for testing of transmission equipment clock switch delayed time system as claimed in claim 1, it is characterized in that, when maintenance information delay in the delayed time system was switched in test, the mode of operation of each network element was configured to clock synchronization information (SSM) in the described step (two); First network element clock priority is configured to follow the tracks of external clock and network element internal clock, and the internal clocking sign of first network element will not dispose; The clock priority of N-1 network element after the first network element is configured to follow the tracks of line clock and network element internal clock; Input in the described step (three) before the operation or the external clock information that changes first network element are the disconnecting external clock.
3. the method for testing of transmission equipment clock switch delayed time system as claimed in claim 1, it is characterized in that, when maintenance information delay in the delayed time system was switched in test, the mode of operation of each network element was configured to clock synchronization information (SSM) in the described step (two); The clock priority of N-1 network element after the first network element is configured to follow the tracks of line clock and network element internal clock; Being configured to of the internal clocking quality of each network element increased in regular turn; Input in the described step (three) before the operation or the external clock information that changes first network element are the disconnecting external clock.
4. the method for testing of transmission equipment clock switch delayed time system as claimed in claim 1, it is characterized in that, when non-switch messages time-delay in the delayed time system is switched in test, N in the described step () is not less than 3, and the mode of operation of each network element is configured to clock synchronization information (SSM) in the described step (two); First network element clock priority is configured to follow the tracks of external clock and network element internal clock, and the external clock quality of first network element is configured to be higher than the network element internal clock quality of first network element; N-1 network element priority after the first network element is configured to follow the tracks of line clock and network element internal clock; N-2 network element internal clock quality after the first network element before last network element is configured to all be lower than the network element internal clock quality of first network element, and the internal clocking quality of last network element is configured to be higher than first network element internal clock quality; Input in the described step (three) before the operation or the external clock information that changes first network element are for changing to the quality of external clock the quality of the internal clocking that is lower than first network element.
5. the method for testing of transmission equipment clock switch delayed time system as claimed in claim 1, it is characterized in that, switch switch messages when time-delay in the delayed time system when test, the mode of operation of each network element is configured to clock synchronization information (SSM) in the described step (two); First network element clock priority is configured to an outside clock, outside two clocks and network element internal clock, the quality of outside one clock of first network element is lower than the quality of network element internal clock, and the quality of outside two clocks is configured to be not less than the quality of its network element internal clock; N-1 network element priority after the first network element is configured to follow the tracks of line clock, external clock and network element internal clock; The external clock quality that the quality of N-1 network element after the first network element is configured to each network element is higher than the quality that it is followed the tracks of the quality of line clock and is not less than its internal clocking, and input in the described step (three) before the operation or the external clock information that changes first network element change to the quality that is not less than outside two clocks for the quality with an outside clock and is not less than the external clock quality of first network element N-1 network element afterwards.
6. the method for testing of transmission equipment clock switch delayed time system as claimed in claim 5 is characterized in that, the external clock of N-1 network element after outside two clocks of described first network element and the first network element can substitute with the line clock two of same quality.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB021525307A CN100373828C (en) | 2002-11-21 | 2002-11-21 | Method for testing clock reverse delay system of transmission equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB021525307A CN100373828C (en) | 2002-11-21 | 2002-11-21 | Method for testing clock reverse delay system of transmission equipment |
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| CN1503481A CN1503481A (en) | 2004-06-09 |
| CN100373828C true CN100373828C (en) | 2008-03-05 |
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Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100872771B1 (en) * | 2007-09-04 | 2008-12-09 | 한국전자통신연구원 | Methods and apparatus for time information synchronization using key re-synchronization frame in encryption communications |
| CN101431444B (en) * | 2007-11-07 | 2011-06-22 | 中兴通讯股份有限公司 | Test method for transmission equipment clock synchronous information switching time delay |
| CN104219016B (en) * | 2014-09-10 | 2018-03-09 | 广西电网公司电力科学研究院 | The system of selection of distribution main website and distribution terminal clock synchronization point |
| CN104218677A (en) * | 2014-09-10 | 2014-12-17 | 广西电网公司电力科学研究院 | Method for synchronizing clocks of power distribution master stations and power distribution terminals |
| CN104270433B (en) * | 2014-09-23 | 2017-11-07 | 烽火通信科技股份有限公司 | Distributed SSM protocol processing systems and method based on complicated packet switching system |
| CN109340990A (en) * | 2017-07-31 | 2019-02-15 | 广东美的制冷设备有限公司 | The detection method of cooler compressor starting time |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5825658A (en) * | 1995-09-14 | 1998-10-20 | Vlsi Technology, Inc. | Method and a system for specifying and automatically analyzing multiple clock timing constraints in a VLSI circuit |
| JP2002092057A (en) * | 2000-09-20 | 2002-03-29 | Toshiba Corp | Delay distributing method and computer readable recording medium having the delay distributing program recorded thereon |
-
2002
- 2002-11-21 CN CNB021525307A patent/CN100373828C/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5825658A (en) * | 1995-09-14 | 1998-10-20 | Vlsi Technology, Inc. | Method and a system for specifying and automatically analyzing multiple clock timing constraints in a VLSI circuit |
| JP2002092057A (en) * | 2000-09-20 | 2002-03-29 | Toshiba Corp | Delay distributing method and computer readable recording medium having the delay distributing program recorded thereon |
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