CN109005557B

CN109005557B - Time delay symmetry measuring method, device and system

Info

Publication number: CN109005557B
Application number: CN201811123805.XA
Authority: CN
Inventors: 宋高前; 陈成满
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2018-09-26
Filing date: 2018-09-26
Publication date: 2021-12-07
Anticipated expiration: 2038-09-26
Also published as: WO2020063593A1; CN109005557A

Abstract

The embodiment of the invention discloses a method, a device and a system for measuring time delay symmetry, wherein the method for measuring time delay symmetry comprises the following steps: the first equipment sends first time information to the second equipment; the first equipment receives second time information sent by the second equipment, and third time information is obtained; the second time information is the sum of time information of sending the second time information by the second device and time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of obtaining the first time information by the second device and the first time information, the third time information is the time information of obtaining the second time information by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of sending the second time information by the second device. The embodiment of the invention realizes the measurement of the time delay symmetry of the equipment so as to adapt to the service transmission scene with strict requirements on the time delay symmetry.

Description

Time delay symmetry measuring method, device and system

Technical Field

The present invention relates to, but not limited to, the field of communications, and in particular, to a method, an apparatus, and a system for measuring delay symmetry.

Background

The traditional 2G, 3G and 4G return networks are divided into an Access layer, a convergence layer, a backbone convergence layer and a core layer, and a novel wireless Access Network (C-RAN) forward Network is introduced in the 4G era. In the 5G era, due to the improvement of Radio spectrum resources and the development of a large-scale (Massive) Multiple Input Multiple Output (MIMO) antenna technology, a Common Public Radio Interface (CPRI) Interface under a traditional Radio Access Network (RAN) architecture is difficult to bear a huge bandwidth, and architecture reconfiguration is required. After reconstruction, the baseband processing Unit (BBU) function of 5G will be divided into two functional entities, namely a Centralized Unit (CU) and a Distributed Unit (DU), and the 5GC-RAN will include two-level architectures, namely a Radio Remote Unit (RRU) -DU) and a secondary forward (DU-CU). The CU and DU functions are divided to process the real-time performance of the content for distinguishing, the CU equipment mainly comprises a non-real-time wireless high-level protocol stack function and also supports the function (UP) sinking of a part of core network and the deployment of edge application service, and the DU equipment mainly processes the physical layer function and the L2 function of the real-time performance requirement.

On the other hand, in the 5G era, due to the application of new technologies such as carrier aggregation, multipoint coordination, 5G ultrashort frame structure, high-precision positioning and the like, ultrahigh precision of hundred nanoseconds is required to be met between base stations, and meanwhile, a transmission network needs to have higher-precision time transmission capability, especially a service transmission scene with strict requirements on delay symmetry.

Disclosure of Invention

The embodiment of the invention provides a method, a device and a system for measuring time delay symmetry, which can measure and compensate the time delay symmetry of equipment so as to adapt to a service transmission scene with strict requirements on the time delay symmetry.

The embodiment of the invention provides a time delay symmetry measuring method, which comprises the following steps:

the first equipment sends first time information to the second equipment;

the first equipment receives second time information sent by the second equipment, and third time information is obtained;

the second time information is the sum of time information of sending the second time information by a second device and time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of obtaining the first time information by the second device and the first time information, the third time information is the time information of obtaining the second time information by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of sending the second time information by the second device;

and the first equipment carries out time delay symmetry compensation according to the second time information and the third time information.

In this embodiment of the present invention, the performing delay symmetry compensation according to the second time information and the third time information includes:

when the first device obtains n pieces of second time information and n pieces of corresponding third time information, the first device rejects the maximum value and the minimum value of the n pieces of second time information, and rejects the maximum value and the minimum value of the n pieces of corresponding third time information; calculating an average value of the second time information and an average value of the third time information; performing time delay symmetry compensation according to the average value of the second time information and the average value of the third time information; wherein n is an integer greater than or equal to 3.

In this embodiment of the present invention, the sending, by the first device, the first time information to the second device includes:

the first equipment replaces the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carries the first time information in part or all of the third type of specific identification code blocks and transmits the first time information to the second equipment; wherein the third type specific identification code block comprises at least one of: the second type specific identification code block and the S identification code block;

the receiving, by the first device, the second time information sent by the second device includes:

and the first equipment analyzes the third type specific identification code block in the received code stream to obtain second time information.

In this embodiment of the present invention, the sending, by the first device, the first time information carried in part or all of the third type specific identifier code blocks to the second device includes:

the first device adds 1 to the sequence number of the local sequence every time it encounters one of the third type of specific identity code blocks; or, the first device adds 1 to the sequence number of the local sequence when the K code is effectively indicated as a first preset indication value;

the first device obtains the first time information when the sequence number of the local sequence is a first preset value, and the first time information is carried in the corresponding third type specific identifier code block when the sequence number of the local sequence is the first preset value and is sent to the second device.

In this embodiment of the present invention, after the first device obtains the first time information when the sequence number of the local sequence is a first preset value, the method further includes:

and the first equipment calculates a cyclic redundancy check code, and when the sequence number of the local sequence is a first preset value, the corresponding third specific identification code block carries the first time information and the cyclic redundancy check code and sends the first time information and the cyclic redundancy check code to the second equipment.

In an embodiment of the present invention, the first-type specific identity code block includes at least one of: the idle information identification code block and the K code between the T identification code block and the S identification code block;

the second type specific identification code block comprises at least one of the following: o identification code block and S identification code block.

the second equipment receives the first time information sent by the first equipment and acquires fourth time information; the fourth time information is the time information of the second device obtaining the first time information;

the second device calculates delay information from the first device to the second device according to the fourth time information and the first time information;

the second device judges the validity of the delay information from the first device to the second device, and when the delay information is valid, the second device sends second time information to the first device;

the second time information is the sum of the time information for sending the second time information and the time delay information from the first device to the second device.

In this embodiment of the present invention, the receiving, by the second device, the first time information sent by the first device includes:

the second equipment analyzes a third type specific identification code block in a received code stream to obtain the first time information;

the second device sending the second time information to the first device includes:

the second equipment replaces the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carries second time information in part or all of the third type of specific identification code blocks and transmits the second time information to the first equipment; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block.

In this embodiment of the present invention, before the second device parses the third type specific identifier code block in the received code stream to obtain the first time information, the method further includes:

and the second equipment performs cyclic redundancy check code check on the third specific identification code block, and analyzes the third specific identification code block after the check is passed to obtain the first time information.

In this embodiment of the present invention, the carrying and transmitting the second time information in part or all of the third type specific identifier code blocks includes:

adding 1 to the sequence number of the local sequence every time the second device encounters one of the third type specific identification code blocks; or the second device adds 1 to the sequence number of the local sequence when the K code is effectively indicated as a second preset indication value;

and the second device acquires time information for sending the second time information when the sequence number of the local sequence is a second preset value, and sends the second time information carried in the corresponding third type specific identifier code block to the first device when the sequence number of the local sequence is the second preset value.

the first equipment sends first time information to the second equipment;

the first equipment receives fifth time information sent by the second equipment, and third time information is obtained; wherein the fifth time information includes: the second device obtains the time information of the first time information and the time information of the fifth time information sent by the second device, wherein the third time information is the time information of the fifth time information obtained by the first device;

the first device calculates a first difference value between the time information of the first time information obtained by the second device and the first time information, and a second difference value between the third time information and the time information of the fifth time information sent by the second device.

In an embodiment of the present invention, the method further includes:

and the first equipment carries out time delay symmetry compensation according to the first difference and the second difference.

In this embodiment of the present invention, the performing, by the first device, the delay symmetry compensation according to the first absolute value and the second absolute value includes:

when the first device obtains n first difference values and n corresponding second difference values, eliminating the maximum value and the minimum value of the n first difference values, and eliminating the maximum value and the minimum value of the n corresponding second difference values; calculating an average of the first difference and an average of the second difference; performing time delay symmetry compensation according to the average value of the first difference value and the average value of the second difference value; wherein n is an integer greater than or equal to 1.

In this embodiment of the present invention, the fifth time information further includes first time information.

the first equipment replaces the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carries first time information in part or all of the third type of specific identification code blocks and transmits the first time information to the second equipment; wherein the third type specific identification code block comprises at least one of: the second type specific identification code block and the S identification code block;

the receiving, by the first device, the fifth time information sent by the second device includes:

and the first equipment analyzes the third specific identification code block in the received code stream to obtain fifth time information.

the second equipment sends fifth time information to the first equipment; wherein the fifth time information includes: the fourth information and time information for transmitting the fifth time information.

In this embodiment of the present invention, after the fourth time information is obtained, the method further includes:

the second device judges the validity of the first time information and the fourth time information;

and when the first time information and the fourth time information are both valid, carrying the fifth time information in part or all of the second type specific identification code blocks and sending the fifth time information to the first device.

In this embodiment of the present invention, the receiving, by the second device, the first time information sent by the second device includes:

the second equipment analyzes a third type specific identification code block in the received code stream to obtain first time information;

the second device sending the fifth time information to the first device includes:

the second equipment replaces the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carries fifth time information in part or all of the third type of specific identification code blocks and transmits the fifth time information to the first equipment; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block.

The embodiment of the invention provides a time delay symmetry measuring device, which comprises a processor and a computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium, and when the instructions are executed by the processor, any one of the time delay symmetry measuring methods is realized.

An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps of any one of the above-mentioned delay symmetry measurement methods.

The embodiment of the invention provides a time delay symmetry measuring system, which comprises:

the first equipment is used for sending first time information to the second equipment; receiving second time information and acquiring third time information; the second time information is the sum of time information of sending the second time information by a second device and time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of obtaining the first time information by the second device and the first time information, the third time information is the time information of obtaining the second time information by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of sending the second time information by the second device;

the second equipment is used for receiving the first time information sent by the first equipment and acquiring fourth time information; the fourth time information is the time information of the second device obtaining the first time information; calculating delay information from the first device to the second device according to the fourth time information and the first time information; sending second time information to the first device; and the second time information is the sum of the time information for sending the second time information and the delay information.

the first equipment is used for sending first time information to the second equipment; receiving fifth time information sent by the second equipment, and acquiring third time information; wherein the fifth time information includes: the second device obtains the time information of the first time information and the time information of the fifth time information sent by the second device, wherein the third time information is the time information of the fifth time information obtained by the first device; calculating a first difference value between the time information of the second device receiving the first time information and the first time information, and a second difference value between the third time information and the time information of the second device sending the fifth time information; performing time delay symmetry compensation according to the first difference and the second difference;

the second equipment is used for receiving the first time information sent by the first equipment and acquiring fourth time information; the fourth time information is the time information of the second device obtaining the first time information; transmitting the fifth time information to the first device; wherein the fifth time information includes: the fourth information and time information for transmitting the fifth time information.

The embodiment of the invention comprises the following steps: the first equipment sends first time information to the second equipment; the first equipment receives second time information sent by the second equipment, and third time information is obtained; the second time information is the sum of time information of sending the second time information by the second device and time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of obtaining the first time information by the second device and the first time information, the third time information is the time information of obtaining the second time information by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of sending the second time information by the second device. The embodiment of the invention realizes the measurement of the time delay symmetry of the equipment so as to adapt to the service transmission scene with strict requirements on the time delay symmetry.

In another embodiment of the present invention, the first device replaces the first type specific identifier code block in the transmission code stream with the second type specific identifier code block, and the first time information is carried in part or all of the third type specific identifier code blocks and is transmitted to the second device; wherein the third type specific identification code block comprises at least one of: a second-type specific identification code block and an S identification code block; and the first equipment analyzes the third type specific identification code block in the received code stream to obtain second time information. According to the embodiment of the invention, the transmission of the time information is realized by replacing the first type of specific identification code block with the second type of specific identification code block, and no extra bandwidth is occupied.

Additional features and advantages of embodiments of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of the invention. The objectives and other advantages of the embodiments of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the examples of the invention serve to explain the principles of the embodiments of the invention and not to limit the embodiments of the invention.

FIG. 1(a) is a schematic diagram of an optical fiber direct connection scheme according to an embodiment of the present invention;

fig. 1(b) is a first schematic diagram of a bearer scheme of a forwarding device according to an embodiment of the present invention;

fig. 1(c) is a schematic diagram of a bearer scheme of a forwarding device according to an embodiment of the present invention;

fig. 2 is a flowchart of a method for measuring symmetry of delay according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of an S-mark code block and an O-mark code block according to an embodiment of the present invention;

FIG. 4(a) is a schematic diagram of a structure of time information;

fig. 4(b) is a diagram illustrating an embodiment of carrying time information in a third type specific identifier code block;

fig. 4(c) is a diagram illustrating a second example of carrying time information in a third type specific identifier code block according to an embodiment of the present invention;

fig. 5 is a flowchart of a method for measuring symmetry of delay according to another embodiment of the present invention;

fig. 6 is a flowchart of a method for measuring symmetry of delay according to another embodiment of the present invention;

fig. 7 is a flowchart of a method for measuring symmetry of delay according to another embodiment of the present invention;

fig. 8 is a schematic structural diagram of a delay symmetry measurement apparatus according to another embodiment of the present invention;

fig. 9 is a schematic structural diagram of a delay symmetry measurement apparatus according to another embodiment of the present invention;

fig. 10 is a schematic structural diagram of a delay symmetry measurement apparatus according to another embodiment of the present invention;

fig. 11 is a schematic structural diagram of a delay symmetry measurement apparatus according to another embodiment of the present invention;

FIG. 12(a) is a first diagram illustrating time information transmission according to an embodiment of the present invention;

FIG. 12(b) is a diagram illustrating time information transmission according to the second embodiment of the present invention;

FIG. 12(c) is a third schematic diagram of time information delivery according to the embodiment of the present invention;

FIG. 12(d) is a diagram illustrating time information transmission according to a fourth embodiment of the present invention;

fig. 13 is a schematic network diagram of cpri service topology according to an embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments of the present invention may be arbitrarily combined with each other without conflict.

The steps illustrated in the flow charts of the figures may be performed in a computer system such as a set of computer-executable instructions. Also, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

The connection of services with strict requirements on time delay symmetry mainly comprises an optical fiber direct connection scheme and an equipment bearing scheme; as shown in fig. 1(a), the optical fiber direct connection scheme is adopted, that is, the user-side devices (such as the device a and the device B shown in fig. 1 (a)) are directly connected through optical fibers without passing through other carrying devices; fig. 1(B) shows an equipment bearer scheme, that is, a user-side device (e.g., device a and device B shown in fig. 1 (B)) is connected to another user-side device through at least 2 bearer devices (e.g., device 1 and device 2 shown in fig. 1(B), and device 1, device 2, and device 3 shown in fig. 1 (c)). In order to meet the strict requirement of the service on the symmetry of the time delay, the equipment bearing scheme needs to achieve the performance close to the direct connection of the optical fiber, and great challenges are provided for the time delay jitter and the symmetry of the equipment.

Flexible Ethernet (FlexE-Flexible Ethernet) technology was developed by the international organization for standardization Optical networking Forum (OIF) at 3 months 2015 and officially released through relevant technical documents at 3 months 2016. The flexible ethernet technology provides a general mechanism to transmit a series of services with different Media Access Control (MAC) rates, which may be a service with a relatively high MAC rate or a collection of services with relatively low MAC rates, and is not limited to a service with a single MAC rate.

The difference between the Flexible Ethernet (FlexE Ethernet) and the conventional Ethernet structure is that the Flexible Ethernet has an extra Shim (FlexE Shim) at the MAC layer and the Physical Coding Sublayer (PCS) layer, and the Shim functions to construct a 20 × n size of a pendar (template) with 66b blocks, where n is the number of bonded Ethernet Physical layers (PHYs), and each 66b block represents a 5G timeslot. On the multiplexing side, services with different MAC rates are loaded into the corresponding number of 66b blocks according to the multiple relation with 5G. Each 20 b blocks form a sub-calenar, and the calenar with the size of 20 multiplied by n is distributed into n sub-calenar. For each sub-call, the overhead of one 66b block is added every 20 × 1023 66b blocks to store the associated mapping, and each sub-call is transmitted in a single 100G ethernet PHY. At the demultiplexing side, n sub-callendars form a 20 Xn callendar, and corresponding client services are extracted from the 66b blocks in the corresponding number according to the mapping relation stored in the overhead. Wherein the overhead is defined by O-code spreading.

802.3 defines several classes of coding, including:

idle characters (I, idle) for adding and deleting in response to a Process Control System (PCS) clock rate change;

a start character (S, start) for indicating the start of a data packet;

a termination character (T) for indicating the termination of a data packet;

control characters (O, ordered _ set) for transmitting an extension of the link-based control and status information.

Referring to fig. 2, an embodiment of the present invention provides a method for measuring symmetry of delay, including:

step 200, the first device sends first time information to the second device.

In this embodiment of the present invention, the first device may be any device, such as a bearer device, a forwarding device, an Edge device (PE, Provider Edge), an Edge router, and the like.

In the embodiment of the present invention, the first device may transmit the first time information t1 to the second device in various ways. For example, the first device replaces the first type specific identifier code block in the transmitted code stream with the second type specific identifier code block, and the first time information t1 is carried in part or all of the third type specific identifier code blocks and is transmitted to the second device; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block. Thus, no extra bandwidth is occupied when transmitting the time information.

In the embodiment of the present invention, the first device may replace the first-type specific identity code blocks in the transmission code stream with the second-type specific identity code blocks according to a predetermined rule, for example, every m first-type specific identity code blocks are replaced with the second-type specific identity code blocks, that is, there are (m-1) first-type specific identity code blocks between two adjacent second-type specific identity code blocks.

In an embodiment of the present invention, the first-type specific identification code block includes at least one of:

the idle information identification code block and the K code between the T identification code block and the S identification code block;

In a specific implementation process, an IDLE Information (IDLE) identification code block between a T identification code block and an S identification code block is replaced by an O identification code block, or a K code is replaced by an S identification code block.

The structure of the S identity code block (also referred to as a header block) and the O identity code block is shown in fig. 3.

0-1 bits are 66Bit (Bit) block type: 10 is a control block (e.g., an O mark code block, an S mark code block), and 01 is a data block;

bits 2-9 are 66bit block subtypes: an S block (i.e., S-mark code block) when 0x 78; o blocks (i.e., O identity code blocks) when 0x 4B;

the 10-65 bits of the S block are data content, and are data with fixed content in actual use.

The 10-33 bits of the O block are data content, the 34-41 bits are feature code, and the 42-65 bits are data content.

Then, as shown in fig. 4(a) and 4(b), the original time information is represented by 80 bits, where the first 48 bits represent second-level time information and the last 32 bits represent nanosecond-level time information, and the embodiment of the invention uses 32 bits (e.g., data2 through data5) in the third-type specific identification code block to represent nanosecond-level time information (instant stamp information).

As shown in fig. 4(b), 18-33 bits of the third type specific identification code block may be extended to 16 high bits of nanosecond time information, where 18-19 bits are used to indicate that the type is a delivered time information type (TS _ type), and as shown in fig. 4(a), when TS _ type is 0, the default type is indicated, when TS _ type is 1, the request type (TS _ req) is indicated, when TS _ type is 2, the response type (TS _ resp) is indicated, and when TS _ type is 3, the TS negotiation packet is indicated;

the 42-57 bits are extended to the lower 16 bits of nanosecond time information.

In another embodiment of the present invention, the third type of identity-specific code block further carries at least one of:

client number, IDLE number, serial number, Cyclic Redundancy Check (CRC), timestamp valid indication, K code indication.

When a CPRI service enters from a U side, the service does not have S and T, S and T blocks can be added in time after cache processing, the service is forwarded in a network in a packet form, when a packet contains K codes, time information is sampled, timestamp information is added, and a timestamp information effective indication and a K code indication are set to be effective; otherwise, setting the timestamp information valid indication and the K code indication as invalid.

The client codes are numbers of original clients at a user side, a plurality of possible original clients under a part of scenes are converged and then uniformly bear transmission, time delay measurement and adjustment need to cover an end-to-end path closer to the user side, and original client number information is transmitted so as to distinguish path information;

the number of IDLE is the number of I identification code blocks contained before the third type of specific identification code block;

the sequence number is the sequence number of a local sequence corresponding to the third type of specific identification code block;

the CRC is used to check information in the third type of specific identity code block;

the timestamp valid indication is used for indicating whether timestamp information in the third type specific identification code block is valid or not;

the K code indication indicates whether there is a K code in a packet following the third type specific identification code block.

As shown in fig. 4(b), 10-13 bits of the third type identity-specific code block may be extended to the client number; the 14-17 bits are expanded into idle number; 58-61 bits are extended to a sequence number; the 62-65 bits are extended to the CRC of the 66bit block.

As shown in fig. 4(c), when the S-mark code block is used to replace the K code, 18-33 bits of the third type specific mark code block can be extended to the upper 16 bits of the nanosecond-level time information, where 18-19 bits are used to represent the type of time information to be transferred (TS _ type), and as shown in fig. 4(a), TS _ type is 0 to represent the default type, TS _ type is 1 to represent the request type (TS _ req), TS _ type is 2 to represent the response type (TS _ resp), and TS _ type is 3 to represent the TS negotiation packet;

the 10-13 bits are expanded into a client number;

14-15 bit extension reserved bits;

16 bits extended to a K code indication;

a 17 bit extension to timestamp valid indication;

the 18-33 bits are extended to the upper 16 bits of the time stamp information (i.e., nanosecond time information), wherein the 18-19 bits are used to indicate the type of time stamp (i.e., type of time information) to be delivered;

bits 34-41 are reserved bits;

the 42-57 bits are extended to the lower 16 bits of the timestamp information;

58-61 bits are extended to a sequence number;

the 62-65 bits are extended to the CRC of the 66bit block.

The above bit extension is only an example, and the 10-33 bits and 42-65 bits are used to carry the time information not only in the above listed manner, but also in other manners, for example, 18-33 bits are used to represent the lower 16 bits of the time information and 42-57 bits are used to represent the upper 16 bits of the time information. The embodiment of the present invention does not limit which bit is extended to indicate which information, and the specific extension manner is not used to limit the protection scope of the embodiment of the present invention, and is not described herein again.

In the embodiment of the present invention, the first device carrying the first time information t1 in part or all of the third type specific identity code blocks and sending the first time information t1 to the second device includes:

the first device adds 1 to the sequence number of the local sequence every time it encounters one of the third type of specific identity code blocks; or, the first device adds 1 to the sequence number of the local sequence when the K code validity indicates a first preset indication value (for example, the K code validity indicates 1);

the first device obtains the first time information t1 (i.e., the time information of the current device) when the sequence number of the local sequence is a first preset value, and the first time information t1 is carried in the third type specific identifier code block corresponding to the local sequence when the sequence number of the local sequence is the first preset value and is sent to the second device.

For example, if the maximum value of the sequence number of the local sequence is set to be X, when the sequence number of the local sequence is X, if a third type specific identification code block is encountered again, the sequence number of the local sequence is reset to zero.

In another embodiment of the present invention, after the first device acquires the first time information t1 when the sequence number of the local sequence is a first preset value, the method further includes:

and the first device calculates CRC, and when the sequence number of the local sequence is a first preset value, the corresponding third-class specific identification code block carries the first time information t1 and CRC and sends the first time information t1 and CRC to the second device.

Where CRC4 may be used to calculate a CRC value.

Step 201, the first device receives second time information sent by the second device, and obtains third time information; the second time information is the sum of the time information of the second time information sent by the second device and the time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of the second device obtaining the first time information and the first time information, the third time information is the time information of the first device obtaining the second time information, and the time delay information from the second device to the first device is the difference between the third time information and the time information of the second device sending the second time information.

In this embodiment of the present invention, the first device may receive the second time information sent by the second device in a manner corresponding to the first time information t1 sent by the first device to the second device, that is, the first device analyzes the third type specific identifier code block in the received code stream to obtain the second time information.

When the third specific identification code block also carries CRC, the first device performs CRC check on the third specific identification code block, after the CRC check is passed, analyzes a 32-bit time information field of the third specific identification code block, extracts a first 2-bit time information type TS _ type, indicates a response type TS _ resp when the TS _ type is 2, that is, identifies that the time information is the second time information, and acquires the time information of the current device as the third time information t4 when the second time information is identified.

The first device may parse the third type specific identifier code block one by one to determine whether to carry the time information, or extract the time information when the sequence number in the third type specific identifier code block is the second preset value according to a predetermined value with the second device.

In an embodiment of the present invention, the method further includes:

the first device performs delay symmetry compensation according to the second time information t3+ (t2-t1) and the third time information t 4.

Specifically, the first device may perform the delay symmetry compensation according to the second time information and the third time information by using any one of the following methods.

First, the first device obtains one piece of second time information and one piece of corresponding third time information, and performs delay symmetry compensation according to the one piece of second time information and the one piece of corresponding third time information.

When the third time information t4 is greater than the second time information t3+ (t2-t1), the cache waterline is decreased by the absolute value of the difference between the third time information t4 and the second time information t3+ (t2-t 1); when the third time information t4 is equal to the second time information t3+ (t2-t1), keeping the cache waterline unchanged; when the third time information t4 is less than the second time information t3+ (t2-t1), increasing the cache water line by the absolute value of the difference between the third time information t4 and the second time information t3+ (t2-t 1);

secondly, the first device obtains n pieces of second time information and n pieces of corresponding third time information, and performs delay symmetry compensation according to the n pieces of second time information and the n pieces of corresponding third time information.

When the first device obtains n pieces of second time information and n pieces of corresponding third time information, the first device rejects the maximum value and the minimum value in the n pieces of second time information, and rejects the maximum value and the minimum value of the n pieces of corresponding third time information; calculating an average value of the second time information and an average value of the third time information; performing time delay symmetry compensation according to the average value of the second time information and the average value of the third time information; wherein n is an integer greater than or equal to 3.

Specifically, when the average value of the third time information is greater than the average value of the second time information, the cache waterline is reduced, and the reduced value is an absolute value of a difference between the average value of the third time information and the average value of the second time information; when the average value of the third time information is equal to the average value of the second time information, keeping the cache waterline unchanged; and when the average value of the third time information is smaller than the average value of the second time information, increasing the cache waterline, wherein the increased value is the absolute value of the difference between the average value of the third time information and the average value of the second time information.

The embodiment of the invention ensures that the time delay from the sending direction of the first equipment to the receiving direction of the second equipment is basically consistent with the time delay from the sending direction of the second equipment to the receiving direction of the first equipment through the adjustment of the buffer waterline, thereby realizing the adjustment of the time delay symmetry and meeting the transmission requirement of the service with higher requirement on the time delay symmetry.

Referring to fig. 5, another embodiment of the present invention provides a method for measuring symmetry of delay, including:

500, the second device receives the first time information sent by the first device, and acquires fourth time information; the fourth time information is the time information of the second device obtaining the first time information.

In the embodiment of the present invention, the second device may receive the first time information sent by the first device by using a method corresponding to the first time information sent by the first device to the second device, that is, the second device analyzes the third type specific identification code block in the received code stream to obtain the first time information.

In another embodiment of the present invention, before the second device parses the third type specific identifier code block in the received code stream to obtain the first time information, the method further includes:

That is to say, when the third type specific mark code block also carries CRC, the second device performs CRC check on the third type specific mark code block, after the CRC check is passed, analyzes the 32-bit time information field of the third type specific mark code block, extracts the first 2-bit time information type TS _ type, when TS _ type is 1, it indicates the request type TS _ req, that is, it is recognized that the time information is the first time information, and when the first time information is recognized, it acquires the time information of the current device as the fourth time information t2, that is, the second device of the above embodiment receives the time information of the first time information.

The second device may parse the third type specific identifier code block one by one to determine whether to carry the time information, or extract the time information when the sequence number in the third type specific identifier code block is the first preset value according to a predetermined value with the first device.

Step 501, the second device calculates delay information from the first device to the second device according to the fourth time information and the first time information.

Specifically, the delay information is a difference between the fourth time information and the first time information.

Step 502, the second device sends second time information to the first device; and the second time information is the sum of the time information for sending the second time information and the delay information.

In the embodiment of the present invention, the second device may send the second time information to the first device in multiple ways, for example, the second device replaces the first type specific identifier code block in the sending code stream with the second type specific identifier code block, and sends the second time information carried in part or all of the third type specific identifier code block to the first device; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block.

Specifically, the second device adds 1 to the sequence number of the local sequence every time it encounters one of the third type specific identity code blocks; or the second device adds 1 to the sequence number of the local sequence when the K code is effectively indicated as a second preset indication value;

the second device obtains time information t3 (i.e., time information of the current device) for sending the third time information when the sequence number of the local sequence is a second preset value, and the second time information (i.e., t3+ | t2-t1|) is carried in the corresponding third-type specific identifier code block when the sequence number of the local sequence is the second preset value and is sent to the first device.

In another embodiment of the present invention, after the second device obtains the time information for sending the second time information when the sequence number of the local sequence is a second preset value, the method further includes:

and the second equipment calculates CRC, and when the sequence number of the local sequence is a second preset value, the corresponding third-class specific identification code block carries second time information and CRC and sends the second time information and the CRC to the first equipment.

In another embodiment of the present invention, after the second device calculates the delay information from the first device to the second device, the method further includes:

the second device judges the validity of the delay information from the first device to the second device, and when the delay information from the first device to the second device is valid, the second time information is carried in part or all of the second-type specific identification code blocks and is sent to the first device; and when the delay information from the first equipment to the second equipment is invalid, ending the process.

Specifically, when the delay information is 0, it indicates that the delay information is invalid; when the delay information is not 0, it indicates that the delay information is valid.

Referring to fig. 6, another embodiment of the present invention provides a method for measuring symmetry of delay, including:

step 600, the first device sends first time information to the second device.

In this embodiment of the present invention, the first device may be any device, such as a forwarding device, an Edge device (PE), an Edge router, and the like.

In the embodiment of the present invention, the first device may transmit the first time information t1 to the second device in various ways. For example, the first device replaces a first type of specific identifier code block in a transmission code stream with a second type of specific identifier code block, carries first time information in part or all of the third type of specific identifier code blocks, and transmits the first time information to the second device; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block. Thus, no extra bandwidth is occupied when transmitting the time information.

In a specific implementation process, an idle information (I) identification code block between a T identification code block and an S identification code block is replaced by an O identification code block, or a K code is replaced by an S identification code block.

The 10-33 bits of the O block are data content, the 34-41 bits are feature codes, and the data content is obtained before the 42-65 bits are expanded.

As shown in fig. 4(b), 18-33 bits of the unique female type-specific identification code block may be extended to 16 high bits of nanosecond time information, where 18-19 bits are used to indicate that the type of time information is a delivered time information type (TS _ type), and as shown in fig. 4(a), when TS _ type is 0, the default type is indicated, when TS _ type is 1, the request type (TS _ req) is indicated, when TS _ type is 2, the response type (TS _ resp) is indicated, and when TS _ type is 3, the TS negotiation packet is indicated;

the 10-13 bits are expanded into a client number;

14-15 bit extension reserved bits;

16 bits extended to a K code indication;

a 17 bit extension to timestamp valid indication;

bits 34-41 are reserved bits;

the 42-57 bits are extended to the lower 16 bits of the timestamp information;

58-61 bits are extended to a sequence number;

the 62-65 bits are extended to the CRC of the 66bit block.

the first device obtains the first time information (i.e. the time information of the current device) when the sequence number of the local sequence is a first preset value, and the corresponding third-type specific identifier code block carries the first time information and transmits the first time information when the sequence number of the local sequence is the first preset value.

In another embodiment of the present invention, after the first device obtains the first time information when the sequence number of the local sequence is a first preset value, the method further includes:

and the first equipment calculates CRC, and when the sequence number of the local sequence is a first preset value, the corresponding third specific identification code block carries the first time information and the CRC and sends the CRC.

Where CRC4 may be used to calculate a CRC value.

601, the first device receives fifth time information sent by the second device, and obtains third time information; wherein the fifth time information includes: and the second equipment acquires the time information of the first time information and the time information of the fifth time information sent by the second equipment, wherein the third time information is the time information of the fifth time information acquired by the first equipment.

In another embodiment of the present invention, the fifth time information further includes the first time information.

In the embodiment of the present invention, the first device may receive the fifth time information sent by the first device in a manner corresponding to the first time information sent by the first device to the second device, that is, the first device analyzes the third type specific identifier code block in the received code stream to obtain the fifth time information.

When the third specific identification code block also carries CRC, the first device performs CRC check on the third specific identification code block, after the CRC check is passed, analyzes a 32-bit time information field of the third specific identification code block, extracts a first 2-bit time information type TS _ type, indicates a response type TS _ resp when the TS _ type is 2, that is, identifies that the time information is the fifth time information, and acquires the time information of the current device as the third time information t4 when the fifth time information is identified.

Step 602, the first device calculates a first difference between the time information of the first time information obtained by the second device and the first time information, and a second difference between the third time information and the time information of the fourth time information sent by the second device; and the first equipment carries out time delay symmetry compensation according to the first difference and the second difference.

Specifically, the first device may perform the delay symmetry compensation according to the first difference and the second difference by using any one of the following methods.

First, the first device obtains a first difference and a corresponding second difference, and performs delay symmetry compensation according to the first difference and the corresponding second difference.

When the second difference is larger than the first difference, reducing the cache waterline, wherein the reduced value is the absolute value of the difference between the second difference and the first difference; when the second difference is equal to the first difference, keeping the cache waterline unchanged; when the second difference is smaller than the first difference, increasing the cache waterline, wherein the increased value is the absolute value of the difference between the second difference and the first difference;

and secondly, the first equipment acquires n first difference values and n corresponding second difference values, and performs time delay symmetry compensation according to the n first difference values and the n corresponding second difference values.

When n first difference values and n corresponding second difference values are obtained, eliminating the maximum value and the minimum value of the n first difference values, and eliminating the maximum value and the minimum value of the n corresponding second difference values; calculating an average of the first difference and an average of the second difference; performing time delay symmetry compensation according to the average value of the first difference value and the average value of the second difference value; wherein n is an integer greater than or equal to 3.

Specifically, when the average value of the second difference is greater than the average value of the first difference, the cache waterline is reduced, and the reduced value is the absolute value of the difference between the average value of the second difference and the average value of the first difference; when the average value of the second difference value is equal to the average value of the first difference value, keeping the cache waterline unchanged; and when the average value of the second difference value is smaller than the average value of the first difference value, increasing the cache waterline, wherein the increased value is the absolute value of the difference between the average value of the second difference value and the average value of the first difference value.

Referring to fig. 7, another embodiment of the present invention provides a method for measuring symmetry of delay, including:

step 700, the second device receives the first time information sent by the first device, and acquires fourth time information; the fourth time information is the time information of the second device obtaining the first time information.

In another embodiment of the present invention, before the second device parses the second type specific identifier code block in the received code stream to obtain the first time information, the method further includes:

Step 701, the second device determines validity of the first time information and the fourth time information; when the first time information and the fourth time information are both valid, the second device sends fifth time information to the first device; wherein the fifth time information includes: the fourth information t2 and time information t3 to transmit the fifth time information.

In the embodiment of the present invention, when the first time information is 0, it indicates that the first time information is invalid; when the first time information is not 0, it indicates that the first time information is valid.

When the fourth time information is 0, the fourth time information is invalid; and when the fourth time information is not 0, the fourth time information is valid.

In another embodiment of the present invention, the fifth time information further includes the first time information t 1.

In this embodiment of the present invention, the second device may send the fifth time information to the first device in multiple ways, for example, the second device replaces the first type specific identifier code block in the sending code stream with the second type specific identifier code block, and sends the fifth time information carried in part or all of the third type specific identifier code block to the first device; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block.

and the second device acquires time information (i.e., time information of the current device) for sending the fifth time information when the sequence number of the local sequence is a second preset value, and sends the fifth time information carried in the third type specific identifier code block corresponding to the local sequence when the sequence number of the local sequence is the second preset value to the first device.

In another embodiment of the present invention, after the second device obtains the time information for sending the fifth time information when the sequence number of the local sequence is a second preset value, the method further includes:

and the second equipment calculates CRC, and when the sequence number of the local sequence is a second preset value, the corresponding third-class specific identification code block carries fifth time information and CRC and sends the fifth time information and the CRC.

In another embodiment of the present invention, after the second device acquires the fourth time information, the method further includes:

referring to fig. 8, another embodiment of the present invention provides a delay symmetry measuring apparatus (e.g., a first device), including:

a first sending module 801, configured to send first time information to a second device;

a first receiving module 802, configured to receive second time information sent by a second device, and obtain third time information;

the second time information is the sum of the time information of the second time information sent by the second device and the time delay information from the first device to the second device, the time delay information from the first device to the second device is the absolute value of the difference between the time information of the first time information obtained by the second device and the first time information, the third time information is the time information of the second time information obtained by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of the second time information sent by the second device.

In this embodiment of the present invention, the first sending module 801 is specifically configured to:

replacing the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carrying first time information in part or all of the third type of specific identification code blocks and transmitting the first time information to second equipment; wherein the third type specific identification code block comprises at least one of: the second type specific identification code block and the S identification code block;

the first receiving module 802 is specifically configured to:

and analyzing the third type specific identification code block in the received code stream to obtain second time information and acquiring third time information.

In another embodiment of the present invention, the method further comprises:

a first compensation module 803, configured to perform delay symmetry compensation according to the second time information and the third time information.

In this embodiment of the present invention, the first compensation module 803 is specifically configured to:

when n pieces of second time information and n pieces of corresponding third time information are obtained, eliminating the maximum value and the minimum value in the n pieces of second time information, and eliminating the maximum value and the minimum value in the n pieces of corresponding third time information; calculating an average value of the second time information and an average value of the third time information; performing time delay symmetry compensation according to the average value of the second time information and the average value of the third time information; wherein n is an integer greater than or equal to 1.

adding 1 to the sequence number of the local sequence every time a third type of specific identification code block is encountered; or adding 1 to the sequence number of the local sequence when the K code effective indication is a first preset indication value;

and when the sequence number of the local sequence is a first preset value, the first time information is acquired, and when the sequence number of the local sequence is the first preset value, the first time information is carried in the corresponding third type specific identification code block and is sent to the second device.

In this embodiment of the present invention, the first sending module 801 is further configured to:

and calculating a cyclic redundancy check code, and when the sequence number of the local sequence is a first preset value, carrying the first time information and the cyclic redundancy check code in the corresponding third specific identification code block and sending the third specific identification code block to second equipment.

The specific implementation process of the delay symmetry measurement apparatus is the same as that in the foregoing embodiment, and is not described here again.

Referring to fig. 9, another embodiment of the present invention provides a delay symmetry measuring apparatus (e.g., a second device), including:

a second receiving module 901, configured to receive the first time information sent by the first device, and obtain fourth time information; the fourth time information is the time information of the second device obtaining the first time information;

a first calculating module 902, configured to calculate, according to the fourth time information and the first time information, delay information from the first device to the second device;

a second sending module 903, configured to send second time information to the first device;

and the second time information is the sum of the time information for sending the second time information and the time delay information from the first equipment to the second equipment.

In this embodiment of the present invention, the second receiving module 901 is specifically configured to:

analyzing a third type specific identification code block in the received code stream to obtain first time information and obtain fourth time information;

the second sending module 903 is specifically configured to:

replacing the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carrying second time information in part or all of the third type of specific identification code blocks and transmitting the second time information to the first equipment; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block.

In this embodiment of the present invention, the second sending module 903 is further configured to:

and judging the validity of the delay information from the first equipment to the second equipment, and carrying the second time information in part or all of the third-class specific identification code blocks and sending the second time information to the first equipment when the delay information from the first equipment to the second equipment is valid.

In this embodiment of the present invention, the second receiving module 901 is further configured to:

and performing cyclic redundancy check code check on the third specific identification code block, and analyzing the third specific identification code block after the check is passed to obtain the first time information.

In this embodiment of the present invention, the second sending module 903 is specifically configured to:

adding 1 to the sequence number of the local sequence every time a third type of specific identification code block is encountered; or adding 1 to the sequence number of the local sequence when the K code is effectively indicated as a second preset indication value;

and when the sequence number of the local sequence is a second preset value, acquiring time information for sending the second time information, and when the sequence number of the local sequence is the second preset value, carrying the second time information in the corresponding third-class specific identifier code block and sending the second time information to the first device.

Referring to fig. 10, another embodiment of the present invention provides a delay symmetry measuring apparatus (e.g., a first device), including:

a third sending module 1001, configured to send the first time information to the second device;

a third receiving module 1002, configured to receive fifth time information sent by the second device, and obtain third time information; wherein the fifth time information includes: the second device obtains the time information of the first time information and the time information of the fifth time information sent by the second device, wherein the third time information is the time information of the fifth time information obtained by the first device;

a second calculating module 1003, configured to calculate a first difference between the time information when the second device receives the first time information and the first time information, and a second difference between the third time information and the time information when the second device sends the fourth time information;

a second compensation module 1004, configured to perform delay symmetry compensation according to the first difference and the second difference.

In this embodiment of the present invention, the third sending module 1001 is specifically configured to:

the third receiving module 1002 is specifically configured to:

and analyzing the third specific identification code block in the received code stream to obtain fifth time information, and acquiring third time information.

In this embodiment of the present invention, the second compensation module 1004 is specifically configured to:

when n first difference values and n corresponding second difference values are obtained, eliminating the maximum value and the minimum value of the n first difference values, and eliminating the maximum value and the minimum value of the n corresponding second difference values; calculating an average of the first difference and an average of the second difference; performing time delay symmetry compensation according to the average value of the first difference value and the average value of the second difference value; wherein n is an integer greater than or equal to 1.

Referring to fig. 11, another embodiment of the present invention provides a method (e.g., a second device) for measuring symmetry of delay, including:

a fourth receiving module 1101, configured to receive the first time information sent by the first device, and acquire fourth time information; the fourth time information is the time information of the second device obtaining the first time information;

a fourth sending module 1102, configured to determine validity of the first time information and the fourth time information;

when the first time information and the fourth time information are both valid, sending fifth time information to second equipment; wherein the fifth time information includes: the fourth information and time information for transmitting the fifth time information.

In this embodiment of the present invention, the fourth receiving module 1101 is specifically configured to:

the fourth sending module 1102 is specifically configured to:

replacing the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carrying fifth time information in part or all of the third type of specific identification code blocks and transmitting the fifth time information to the first equipment; wherein the third type specific identification code block comprises at least one of: the second-type specific identification code block and the S identification code block.

Another embodiment of the present invention provides a delay symmetry measuring apparatus, including a processor and a computer-readable storage medium, where instructions are stored in the computer-readable storage medium, and when the instructions are executed by the processor, the apparatus implements any one of the above delay symmetry measuring methods.

Another embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the steps of any one of the above-mentioned delay symmetry measuring methods.

Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, Digital Versatile Disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by a computer.

Another embodiment of the present invention provides a system for measuring symmetry of time delay, including:

the first equipment is used for sending first time information to the second equipment; receiving second time information sent by second equipment, and acquiring third time information; the second time information is the sum of time information of sending the second time information by the second device and time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of obtaining the first time information by the second device and the first time information, the third time information is the time information of obtaining the second time information by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of sending the second time information by the second device;

In an embodiment of the present invention, the first device is specifically configured to:

replacing the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carrying first time information in part or all of the third type of specific identification code blocks and transmitting the first time information to second equipment; wherein the third type specific identification code block comprises at least one of: the second type specific identification code block and the S identification code block; analyzing a third type specific identification code block in the received code stream to obtain second time information and acquiring third time information;

the second device is specifically configured to:

analyzing a third type specific identification code block in the received code stream to obtain first time information and obtain fourth time information; calculating delay information from the first device to the second device according to the fourth time information and the first time information; and replacing the first type of specific identification code block in the transmitted code stream with a second type of specific identification code block, wherein part or all of the third type of specific identification code block carries second time information and is transmitted to the first equipment.

In another embodiment of the invention, the first device is further configured to:

and performing time delay symmetry compensation according to the second time information and the third time information.

In this embodiment of the present invention, the first device is specifically configured to implement the delay symmetry compensation according to the second time information and the third time information in the following manner:

when the sequence number of the local sequence is a first preset value, acquiring the first time information, calculating a cyclic redundancy check code, and when the sequence number of the local sequence is the first preset value, carrying the first time information and the cyclic redundancy check code in the corresponding third specific identifier code block and sending the third specific identifier code block to second equipment;

the second device is further configured to:

In another embodiment of the invention, the second device is further adapted to:

and judging the validity of the delay information from the first equipment to the second equipment, and carrying the second time information in part or all of the third specific identification code blocks and sending the second time information to the first equipment when the delay information is valid.

The specific implementation process of the delay symmetry measurement system is the same as that in the foregoing embodiment, and is not described here again.

the first equipment is used for sending first time information to the second equipment; receiving fifth time information and acquiring third time information; wherein the fifth time information includes: the second device obtains the time information of the first time information and the time information of the fifth time information sent by the second device, wherein the third time information is the time information of the fifth time information obtained by the first device; calculating a first difference value between the time information of the first time information obtained by the second device and the first time information, and a second difference value between the third time information and the time information of the fifth time information sent by the second device; performing time delay symmetry compensation according to the first difference and the second difference;

the second equipment is used for receiving the first time information sent by the first equipment and acquiring fourth time information; the fourth time information is the time information of the second device obtaining the first time information; judging the validity of the first time information and the fourth time information; when the first time information and the fourth time information are both valid, sending fifth time information to the first equipment; wherein the fifth time information includes: the fourth information and time information for transmitting the fifth time information.

In this embodiment of the present invention, the first device is specifically configured to implement sending the first time information to the second device and receiving the fifth time information sent by the second device by using the following manners:

replacing the first type of specific identification code blocks in the transmitted code stream with second type of specific identification code blocks, carrying first time information in part or all of the third type of specific identification code blocks and transmitting the first time information to second equipment; wherein the third type specific identification code block comprises at least one of: the second type specific identification code block and the S identification code block; analyzing a third type specific identification code block in the received code stream to obtain fifth time information;

the second device is specifically configured to:

analyzing a third type specific identification code block in the received code stream to obtain first time information and obtain fourth time information; and replacing the first type of specific identification code block in the transmitted code stream with the second type of specific identification code block, and transmitting part or all of the third type of specific identification code block to the first device, wherein the fifth time information is carried in the third type of specific identification code block.

In this embodiment of the present invention, the first device is specifically configured to implement the delay symmetry compensation according to the first difference and the second difference in the following manner:

Four examples are given below for the FlexE transport pipe defined by OIF, but the implementation is not limited to the FlexE pipe, and may be FlexO, and the like, and these changes are all within the scope of this patent.

As shown in fig. 12(a), the edge device 1 replaces the first type specific identification code block with the second type specific identification code block, sends time information 1 to the edge device 2 through the third type specific identification code block, the edge device 2 receives the time information 1 and obtains the time information 2, replaces the first type specific identification code block with the second type specific identification code block, sends time information 3 to the edge device 1 based on the time information 1 and the time information 2 using the third type specific identification code block, and the edge device 1 receives the time information 3 and obtains the time information 4, thereby implementing symmetric measurement of delay information from the edge device 1 to the edge device 2 and delay information from the edge device 2 to the edge device 1. Wherein the third type specific identification code block comprises at least one of: a second type of specific identity code block, an S identity code block.

Example 1

The service of 25G ethernet common public radio interface (ecpri) directly connected to an optical fiber of an edge device (i.e., a bearer device directly connected to a user side device) is carried in 100G FlexE, and processed time information is transmitted using a header identity code block (S identity code block) or an IDLE information identity code block (IDLE identity code block) or both the header identity code block (S identity code block) and the IDLE information identity code block (IDLE identity code block).

Topological network as shown in fig. 1(b), time information transfer process as shown in fig. 12(b), the method includes:

step 1: in the sending direction of the edge device 1, for the ecpri service with strict requirement on the symmetry of delay, the ecpri service and the time information are carried to the FlexE and then transmitted through the 100G optical fiber.

The step 1 comprises the following steps:

step 1.1: for an IDLE identification code block between a T identification code and an S identification code block in a pcs layer 66/64B code stream defined by a U side (i.e., an entry of an RU antenna, also referred to as a user side, a service port) 802.3 of the edge device 1, replacing a part of the IDLE identification code block with an O identification code block according to a certain rule;

step 1.2: maintaining a local sequence modulo 16; adding 1 to the sequence number of the local sequence every O-id code block or S-id code block, extracting time information t1 (i.e., the first time information of the above-described embodiment) of the current device when the sequence number is 1, and inserting the first time information t1 and the sequence number into the O-id code block or S-id code block and calculating the 66/64B CRC value using CRC4, inserting the CRC value into the O-id code block or S-id code block;

step 1.3: carrying the service to a 100G Flexe pipeline according to the requirement of a Flexe protocol for transmission on the N side;

step 2: and the receiving direction of the edge device 2 obtains the delay information sent by the edge device 1 to the edge device 2 for receiving.

The step 2 comprises the following steps:

step 2.1: extracting a service code block from an N-side (namely a network side) FlexE time slot of the edge device 2, analyzing an O identification code block or an S identification code block, performing CRC (cyclic redundancy check) when reading the O identification code block or the S identification code block, and analyzing each field of the O identification code block or the S identification code block after the check is passed;

step 2.2: when the time information type is ST _ req, identifying the time information type as t1, extracting the time information t2 of the current equipment, calculating | t2-t1| and sending the | t2-t1| to the sending side of the equipment;

and step 3: the sending direction of the edge device 2 carries the forwarding service and the time information with strict requirements on the delay symmetry to the FlexE and then transmits the forwarding service and the time information through the 100G optical fiber.

The step 3 comprises the following steps:

step 3.1: for an IDLE identification code block between a T identification code block and an S identification code block in a pcs layer 66/64B code stream defined by the U side 802.3 of the edge device 2, replacing part of the IDLE identification code block with an O identification code block according to a certain rule;

step 3.2: obtaining timestamp information | t2-t1| obtained from a receiving direction, judging validity of | t2-t1|, and when | t2-t1| is 0, the time information is invalid time information, and the time information is not transmitted; generating a time information transmission request for valid time information when the t2-t1 is not 0;

step 3.3: maintaining a local sequence modulo 16; adding 1 to the sequence number of the local sequence when the O-labeled code block or the S-labeled code block is encountered, extracting time stamp information t3 when the sequence number is 9, calculating t3+ | t2-t1|, generating t3+ | t2-t1| time information, inserting the generated time information and the sequence number 9 into the O-labeled code block or the S-labeled code block, calculating a CRC value of 66/64B by using CRC4, and inserting the CRC value into the O-labeled code block or the S-labeled code block;

step 3.4: carrying the service to a 100G Flexe pipeline according to the requirement of a Flexe protocol for transmission on the N side;

and 4, step 4: and adjusting the time delay to meet the requirement of time delay symmetry in the receiving direction of the edge device 1.

Step 4 comprises the following steps:

step 4.1: extracting a service code block from an N-side Flexe time slot of the edge device 1, analyzing an O identification code block or an S identification code block, performing CRC (cyclic redundancy check) when the O identification code block or the S identification code block is read, and analyzing each field of the O identification code block or the S identification code block after the check is passed;

step 4.2: when the time information type is ST _ resp, extracting time information containing t3+ | t2-t1| and sampling a time stamp t4 of the current equipment to obtain the group of time information t4, t3+ | t2-t1| and sending the group of time information t4 and t3+ | t2-t1| to a time processing unit;

step 4.3: the time processing unit stores 16 groups of time stamp sampling information, removes the maximum value and the minimum value in a certain range, calculates the average value of the rest values, and obtains the average value of t4 and the average value of t3+ | t2-t1 |;

when the average value of t4 is larger than the average value of t3+ | t2-t1|, calculating the absolute difference value of the average value of t4 and the average value of t3+ | t2-t1|, and reducing the corresponding cache waterline;

when the average value of t4 is smaller than the average value of t3+ | t2-t1|, calculating the absolute difference value of the average value of t4 and the average value of t3+ | t2-t1|, and increasing the corresponding cache waterline;

when the average value of t4 is equal to the average value of t3+ | t2-t1|, then the cache waterline does not need to be adjusted;

step 4.4: through the adjustment of a waterline, the time delay from the sending direction of the forwarding equipment 2 to the receiving direction of the forwarding equipment 1 is adjusted to be basically consistent with the time delay from the sending direction of the forwarding equipment 1 to the receiving direction of the forwarding equipment 2, and the symmetry adjustment of the complete time delay is realized; to meet the traffic transmission needs that are highly dependent on delay symmetry.

Example 2

The 25G espri traffic passing through the intermediate node is carried in 100G Flexe, and the processed time information is transferred by using a message header block (S block) or an IDLE information block (IDLE block) or a message header block (S block) and an IDLE information block (IDLE block).

Topological network as shown in fig. 1(c), time information transmission is as shown in fig. 12(c), and at least one intermediate node (i.e. intermediate node device 3 in fig. 1 (c)) is added in the topological network;

the processing of the edge device 1 and the edge device 2 is the same as that of the first embodiment; the intermediate node device 3 transparently transmits the O-id code block or the S-id code block carrying the time information.

Example 3

The 25G copy service passing through the intermediate node is carried in 100G Flexe, and the message header identification code block (S identification code block) or the IDLE information identification code block (IDLE identification code block) or the message header identification code block (S identification code block) and the IDLE information identification code block (IDLE identification code block) are used for transmitting the unprocessed time information.

Topological network as shown in fig. 1(c), time information transfer is shown in fig. 12(d), and the method comprises:

The step 1 comprises the following steps:

step 1.1: for an IDLE identification code block between a T identification code block and an S identification code block in a pcs layer 66/64B code stream defined by the U side 802.3 of the edge device 1, replacing part of the IDLE identification code block with an O identification code block according to a certain rule;

step 1.2: maintaining a local sequence modulo 16; adding 1 to the sequence number of the local sequence every O-id code block or S-id code block, extracting time information t1 (i.e., the first time information of the above-described embodiment) of the current device when the sequence number is 1, and inserting the first time information t1 and the sequence number into the O-id code block or S-id code block and calculating the 66/64B CRC value using CRC4, and inserting the CRC value into the O-id code block or S-id code block;

step 2: the traffic passes through the intermediate node device 3, and the intermediate node device 3 needs to support transparent transmission of the O identity code block or the S identity code block.

And step 3: the receiving direction of the edge device 2 obtains the time information sent by the edge device 1 to the edge device 2.

The step 3 comprises the following steps:

step 3.1: extracting a service code block from an N-side Flexe time slot of the edge device 2, analyzing an O identification code block or an S identification code block, performing CRC (cyclic redundancy check) when the O identification code block or the S identification code block is read, and analyzing each field of the O identification code block or the S identification code block after the check is passed;

step 3.2: when the time information type is ST _ req, identifying the time information type as t1, extracting the time stamp t2 of the current equipment, and transmitting the time information of t2 and t1 to the transmitting side of the equipment;

and 4, step 4: the sending direction of the edge device 2 carries the forwarding service and the time information with strict requirements on the delay symmetry to the FlexE and then transmits the forwarding service and the time information through the 100G optical fiber.

Step 4 comprises the following steps:

step 4.1: for an IDLE identification code block between a T identification code block and an S identification code block in a pcs layer 66/64B code stream defined by the U side 802.3 of the edge device 2, replacing part of the IDLE identification code block with an O identification code block according to a certain rule;

step 4.2: acquiring time information t1 and t2 obtained from a receiving direction, judging the validity of t1 and t2, and when t2 and t1 are 0, the time information is invalid time information and is not transmitted; when t2 and t1 are not 0, the time information is valid, and a time information sending request is generated;

step 4.3: maintaining a local sequence modulo 16; adding 1 to the sequence number of the local sequence every time the O-id code block or the S-id code block, extracting time information t3 (i.e., the time information of the fifth time information sent in the above embodiment) when the sequence number is 9, encapsulating t1, t2, and t3 into the time information, inserting the generated timestamp information and the sequence number into the O-id code block or the S-id code block, calculating the 66/64BCRC value using CRC4, and inserting the CRC value into the O-id code block or the S-id code block;

step 4.4: carrying the service to a 100G Flexe pipeline according to the requirement of a Flexe protocol for transmission on the N side;

and 5: and adjusting the time delay to meet the requirement of time delay symmetry in the receiving direction of the edge device 1.

The step 5 comprises the following steps:

step 5.1: extracting a service code block from an N-side Flexe time slot of the edge device 1, analyzing an O identification code block or an S identification code block, performing CRC (cyclic redundancy check) when the O identification code block or the S identification code block is read, and analyzing each field of the O identification code block or the S identification code block after the check is passed;

step 5.2: when the time information type is ST _ resp, extracting time information containing t1, t2 and t3, sampling time information t4 of the current equipment, obtaining the group of time stamp sampling information t1, t2, t3 and t4, and sending the group of time stamp sampling information t1, t2, t3 and t4 to a time processing unit;

step 5.3: the time processing unit calculates absolute values of | t2-t1|, | t4-t3|, namely obtains delay12 from the edge device 1 to the edge device 2 and delay34 from the edge device 2 to the edge device 1, and stores the set of sample samples of delay12 and delay 34;

step 5.4: storing 16 groups of sampling information, removing the maximum value and the minimum value in a certain range, and calculating the average value of the rest values to obtain the average value of delay12 and the average value of delay 34;

step 5.4.1: when the average value of delay34 is larger than that of delay12, calculating the absolute value of the difference between the average value of delay34 and the average value of delay12, and reducing the corresponding cache waterline;

step 5.4.2: when the average value of delay34 is smaller than that of delay12, calculating the absolute value of the difference between the average value of delay34 and the average value of delay12, and increasing the corresponding cache waterline;

step 5.4.3: when the average value of delay34 is equal to the average value of delay12, then the cache waterline does not need to be adjusted;

step 5.5: through the adjustment of a waterline, the time delay from the sending direction of the forwarding equipment 2 to the receiving direction of the forwarding equipment 1 is adjusted to be basically consistent with the time delay from the sending direction of the forwarding equipment 1 to the receiving direction of the forwarding equipment 2, and the symmetry of the complete time delay is adjusted; to meet the traffic transmission needs that are highly dependent on delay symmetry.

Example 4

Common public radio interface (cpri) service is carried in 100gflex, and S identity code block is used to replace K code carrying time information.

The topological network is shown in fig. 13, and the method includes:

step 1: in the sending direction of the edge device 1, for three paths of cpri services with strict requirements on delay symmetry, cpri and time information are independently carried to FlexE and then transmitted through a 100G optical fiber.

The step 1 comprises the following steps:

step 1.1: replacing the K code with an S identification code block at the U side of the edge device 1;

step 1.2: each CPRI service maintains a modulo-2K code sequence number, when the effective indication of the K code is 1, the sequence number is added with 1, when the sequence number is 0, the time stamp information t1 is extracted, and the effective indication of the time stamp, the first time information, the customer number and the K code indication are inserted into an S identification code block;

step 1.3: each service is loaded into a 100G Flexe pipeline according to the requirement of a Flexe protocol and transmitted on the N side;

The step 2 comprises the following steps:

step 2.1: extracting service code blocks from the Flexe time slots at the N side of the edge device 2, and analyzing S identification code blocks;

step 2.2: when the time information in the S-mark code block is valid and the type of the time information is ST _ req, identifying the time information as first time information t1, extracting a time stamp t2 of the current device, calculating absolute values of | t2-t1| and transmitting the absolute values to the transmitting side of the device;

and step 3: in the sending direction of the

edge device

2, 3 paths of independent cpri services and time information which have strict requirements on delay symmetry are carried to the FlexE and then transmitted through the 100G optical fiber.

The step 3 comprises the following steps:

step 3.1: obtaining timestamp information | t2-t1| obtained from a receiving direction, judging validity of | t2-t1|, and when | t2-t1| is 0, the time information is invalid time information, and the time information is not transmitted; generating a time information transmission request for valid time information when the t2-t1 is not 0;

step 3.2: each CPRI service maintains a modulo-2K code sequence number, when the effective indication of the K code is 1, the sequence number is added with 1, when the sequence number is 1, time stamp information t3 is extracted, t3+ | t2-t1| is calculated, time information is generated, and the effective indication of the time stamp, the time information, the customer number and the K code indication are inserted into the S identification code block;

step 3.3: and carrying the service into a 100G Flexe pipeline according to the requirement of a Flexe protocol for transmission on the N side.

And 4, step 4: the receiving direction of the edge device 1, the delay is adjusted to meet the requirement of delay symmetry,

step 4 comprises the following steps:

step 4.1: extracting service code blocks from the Flexe time slots at the N side of the edge device 1, and analyzing S identification code blocks;

step 4.2: when the time in the S identification code block is valid and the type of the time information is ST _ resp, extracting time stamp information containing t3+ | t2-t1|, sampling the time stamp t4 of the current equipment to obtain the group of time stamp sampling information t4, and sending t3+ | t2-t1| to a time stamp processing unit;

step 4.3: storing 16 groups of timestamp sampling information, removing the maximum value and the minimum value in a certain range, and calculating the average value of the rest values to obtain the average value of t4 and the average value of t3+ | t2-t1 |;

step 4.3.1: when the average value of t4 is larger than the average value of t3+ | t2-t1|, calculating the absolute difference value of the average value of t4 and the average value of t3+ | t2-t1|, and reducing the corresponding cache waterline;

step 4.3.2: when the average value of t4 is smaller than the average value of t3+ | t2-t1|, calculating the absolute difference value of the average value of t4 and the average value of t3+ | t2-t1|, and increasing the corresponding cache waterline;

step 4.3.3: when the average value of t4 is equal to the average value of t3+ | t2-t1|, then the cache waterline does not need to be adjusted;

Although the embodiments of the present invention have been described above, the descriptions are only used for understanding the embodiments of the present invention, and are not intended to limit the embodiments of the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the embodiments of the invention as defined by the appended claims.

Claims

1. A time delay symmetry measurement method comprises the following steps:

the first equipment sends first time information to the second equipment;

the first equipment carries out time delay symmetry compensation according to the second time information and the third time information;

the second time information is the sum of time information of sending the second time information by the second device and time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of obtaining the first time information by the second device and the first time information, the third time information is the time information of obtaining the second time information by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of sending the second time information by the second device.

2. The method of claim 1, wherein the compensating for the delay symmetry according to the second time information and the third time information comprises:

3. The method for measuring the time delay symmetry as claimed in any one of claims 1 to 2, wherein the sending, by the first device, the first time information to the second device includes:

4. The delay symmetry measurement method according to claim 3, wherein the first device carries the first time information in part or all of the third type specific identity code blocks and sends the first time information to the second device includes:

5. The method according to claim 4, wherein after the first device obtains the first time information when the sequence number of the local sequence is a first preset value, the method further comprises:

6. The delay symmetry measurement method according to claim 3, wherein the first type specific identity code block comprises at least one of: the idle information identification code block and the K code between the T identification code block and the S identification code block;

7. A time delay symmetry measurement method comprises the following steps:

the second device sends second time information to the first device;

8. The delay symmetry measurement method according to claim 7, wherein after the second device calculates delay information from the first device to the second device, the method further comprises:

and the second device judges the validity of the delay information from the first device to the second device, and when the delay information is valid, the second device carries the second time information in part or all of the second-type specific identification code blocks and sends the second time information to the first device.

9. The method of claim 7 or 8, wherein the receiving, by the second device, the first time information sent by the first device comprises:

10. The delay symmetry measurement method according to claim 9, wherein before the second device parses the third type specific identification code block in the received code stream to obtain the first time information, the method further comprises:

11. The method of claim 9, wherein the carrying and transmitting second time information in some or all of the third type specific identity code blocks comprises:

12. A time delay symmetry measurement method comprises the following steps:

the first equipment sends first time information to the second equipment;

the first device calculates a first difference value between the time information of the first time information obtained by the second device and the first time information, and a second difference value between the third time information and the time information of the fifth time information sent by the second device;

13. The delay symmetry measurement method of claim 12, wherein the first device performing the delay symmetry compensation according to the first absolute value and the second absolute value comprises:

14. The method according to any one of claims 12 to 13, wherein the fifth time information further includes the first time information.

15. The method for measuring symmetry of time delay according to any one of claims 12 to 13, wherein the sending, by the first device, the first time information to the second device includes:

16. A time delay symmetry measurement method comprises the following steps:

when the first time information and the fourth time information are both valid, the second device sends fifth time information to the first device; wherein the fifth time information includes: the fourth time information and time information for transmitting the fifth time information.

17. The delay symmetry measurement method according to claim 16, wherein the fifth time information further includes the first time information.

18. The delay symmetry measurement method according to claim 16, wherein the receiving, by the second device, the first time information sent by the second device comprises:

19. A delay symmetry measuring apparatus comprising a processor and a computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium, and when the instructions are executed by the processor, the delay symmetry measuring method according to any one of claims 1 to 18 is implemented.

20. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the delay symmetry measurement method according to any one of claims 1 to 18.

21. A delay symmetry measurement system, comprising:

the first equipment is used for sending first time information to the second equipment; receiving second time information and acquiring third time information; performing time delay symmetry compensation according to the second time information and the third time information; the second time information is the sum of time information of sending the second time information by a second device and time delay information from the first device to the second device, the time delay information from the first device to the second device is the difference between the time information of obtaining the first time information by the second device and the first time information, the third time information is the time information of obtaining the second time information by the first device, and the time delay information from the second device to the first device is the difference between the third time information and the time information of sending the second time information by the second device;

22. A delay symmetry measurement system, comprising:

the second equipment is used for receiving the first time information sent by the first equipment and acquiring fourth time information; the fourth time information is the time information of the second device obtaining the first time information; transmitting the fifth time information to the first device; wherein the fifth time information includes: the fourth time information and time information for transmitting the fifth time information.