WO2012174892A1 - Method, system and device for keeping clock synchronization of ntp servers - Google Patents
Method, system and device for keeping clock synchronization of ntp servers Download PDFInfo
- Publication number
- WO2012174892A1 WO2012174892A1 PCT/CN2012/072259 CN2012072259W WO2012174892A1 WO 2012174892 A1 WO2012174892 A1 WO 2012174892A1 CN 2012072259 W CN2012072259 W CN 2012072259W WO 2012174892 A1 WO2012174892 A1 WO 2012174892A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- ntp
- server
- clock
- set time
- difference threshold
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0679—Clock or time synchronisation in a network by determining clock distribution path in a network
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0638—Clock or time synchronisation among nodes; Internode synchronisation
- H04J3/0658—Clock or time synchronisation among packet nodes
- H04J3/0661—Clock or time synchronisation among packet nodes using timestamps
- H04J3/0667—Bidirectional timestamps, e.g. NTP or PTP for compensation of clock drift and for compensation of propagation delays
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/60—Network streaming of media packets
- H04L65/61—Network streaming of media packets for supporting one-way streaming services, e.g. Internet radio
- H04L65/612—Network streaming of media packets for supporting one-way streaming services, e.g. Internet radio for unicast
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/242—Synchronization processes, e.g. processing of PCR [Program Clock References]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0638—Clock or time synchronisation among nodes; Internode synchronisation
- H04J3/0641—Change of the master or reference, e.g. take-over or failure of the master
Definitions
- the invention relates to the field of network television technology, in particular to a NTP (Network Time Protocol) server clock synchronization holding method, system and device.
- NTP Network Time Protocol
- IPTV Interactive Personality TV
- NTP server needs to provide NTP clock synchronization for each IPTV server, and also provides NTP clock synchronization for the Set Top Box (STB). Since the time after the STB is powered on defaults to 1970, the NTP server is configured to not limit the time difference and still provide the NTP clock synchronization service.
- STB Set Top Box
- the NTP server of the IPTV (hereinafter referred to as the NTP-I server) is configured to synchronize the clock from the telecom NTP server (hereinafter referred to as the NTP-T server).
- the NTP-T server is configured to provide the NTP synchronization service if the time difference exceeds 4S.
- the NTP-T server provides the synchronous clock.
- the NTP-I server synchronizes the clock signal from the NTP-T server to implement clock synchronization.
- the NTP synchronization (SYNC) signal is used to synchronize the service servers and set-top boxes. Clock.
- the NTP-I server will fail to perform clock synchronization from the NTP-T server due to the NTP-T server configuration.
- the NTP-I server's error clock will be provided through it.
- the NTP service is synchronized to all IPTV service servers and STBs, causing the service server and the STB clock to be disordered, resulting in abnormal service services. Summary of the invention
- the embodiment of the invention provides a method, a system and a device for maintaining a clock synchronization of an NTP server, which are used to solve the problem that the system clock is disordered and the service service is abnormal when the clock synchronization of the existing NTP server fails.
- a network time protocol NTP server clock synchronization maintenance method including:
- the first NTP-I server and the second NTP-I server synchronize the clock from the telecommunication NTP-T server; the first NTP-I server queries the first clock offset value of the second NTP-I server according to the set time interval.
- the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the local modification is corrected. Clock; and,
- the second NTP-I server queries the third clock deviation value of the first NTP-I server according to the set time interval.
- the second NTP-I server queries itself.
- the fourth clock deviation value from the NTP-T server if the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
- the first NTP-I server queries the first clock offset value between itself and the second NTP-I server according to the set time interval, including:
- the first NTP-I server sends a first clock deviation query request to the second NTP-I server according to the set query time interval, and receives the second NTP-I server returns itself after receiving the first clock deviation query request.
- the first clock offset value from the first NTP-I server.
- the second NTP-I server queries the third clock offset value of the first NTP-I server according to the set time interval, including:
- the second NTP-I server sends a third clock deviation query request to the first NTP-I server according to the set query time interval, and receives the first NTP-I server returns itself after receiving the third clock deviation query request.
- the third clock deviation value from the second NTP-I server.
- the first NTP-I server queries the second clock offset value of the NTP-T server and the NTP-T server. If the second clock offset exceeds the set time difference threshold, the local clock is corrected, including:
- the first NTP-I server sends a second clock deviation query request to the NTP-T server; and receives a second clock offset value between the NTP-T server and the first NTP-I server after receiving the second clock deviation query request. And its own standard clock;
- the local clock is corrected according to the received standard clock.
- the second NTP-I server queries the fourth clock offset value between itself and the NTP-T server. If the fourth clock offset value exceeds the set time difference threshold, the local clock is corrected, including:
- the first NTP-I server sends a second clock deviation query request to the NTP-T server; and receives a second clock offset value between the NTP-T server and the first NTP-I server after receiving the second clock deviation query request. And its own standard clock;
- the local clock is corrected according to the received standard clock.
- the clock synchronization service is provided for the service server by using the first NTP-I server and/or the second NTP-I server, and the clock synchronization service is provided for the set top box by using the first NTP-I server or the second NTP-I server.
- An NTP server clock synchronization maintenance system includes:
- a first NTP-I server configured to synchronize a clock from the telecommunication NTP-T server; query the first clock deviation value of the second NTP-I server according to the set time interval, when the first clock deviation value exceeds the set value
- the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the local clock is corrected;
- a second NTP-I server configured to synchronize a clock from the telecommunication NTP-T server; query a third clock deviation value of the first NTP-I server according to the set time interval, when the third clock is biased
- the second NTP-I server queries the fourth clock deviation value of itself and the NTP-T server, and if the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
- the first NTP-I server is further configured to provide a clock synchronization service for the service server and the set top box; and the second NTP-I server is further configured to provide a clock synchronization service for the service server and a clock synchronization service for the set top box.
- An NTP server including:
- a clock synchronization module configured to synchronize a clock from a telecommunications NTP-T server
- a first query module configured to query a first clock offset value of the second NTP-I server according to the set time interval
- the second query module is configured to: when the first clock deviation value exceeds the set time difference threshold, query the second clock deviation value of the self and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the correction is performed. Local clock.
- the first query module is configured to:
- the second query module is configured to:
- the local clock is corrected according to the received standard clock.
- the NTP server clock synchronization holding method, system and device provided by the embodiment of the present invention, the first NTP-I server and the second NTP-I server mutually query each other's clock offset value, when the first NTP-I server or the first When the NTP-I server finds that the clock deviation between itself and the other party exceeds the set time difference threshold, it queries the clock offset value between itself and the NTP-T server. If the clock offset value between itself and the NTP-T server exceeds the set time difference threshold. , then correct the local clock.
- FIG. 1 is a network diagram of an IPTV system in the prior art
- FIG. 2 is a schematic structural diagram of a clock synchronization and maintenance system of an NTP server according to an embodiment of the present invention
- FIG. 3 is a flowchart of a method for maintaining a clock synchronization of an NTP server according to an embodiment of the present invention
- FIG. 4 is a schematic structural diagram of an NTP server according to an embodiment of the present invention.
- An embodiment of the present invention provides a method for maintaining a clock synchronization of an NTP server, which is implemented by using an NTP server clock synchronization and maintenance system as shown in FIG. 2, where the system includes: a first NTP-I server, a second NTP-I server, and a telecommunications NTP- T server.
- a first NTP-I server configured to synchronize a clock from the telecommunication NTP-T server; query the first clock deviation value of the second NTP-I server according to the set time interval, when the first clock deviation value exceeds the set value
- the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the local clock is corrected.
- a second NTP-I server for synchronizing the clock from the telecommunications NTP-T server;
- the time interval queries the third clock deviation value of the first NTP-I server.
- the second NTP-I server queries the fourth clock deviation of the NTP-T server. Value, if the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
- the above system also includes several business services and set top boxes.
- the first NTP-I server is further configured to provide a clock synchronization service for the service server and the set top box; and the second NTP-I server is further configured to provide a clock synchronization service for the service server and a clock synchronization service for the set top box.
- the first NTP-I server and/or the second NTP-I server provide clock synchronization services for the service server, and the clock synchronization service is provided for the set top box through the first NTP-I server or the second NTP-I server.
- the method for maintaining the clock synchronization of the NTP server provided by the embodiment of the present invention is as shown in FIG. 3, and includes the following steps:
- Step S11 The first NTP-I server and the second NTP-I server synchronize the clock from the telecommunication NTP-T server.
- the first NTP-I server and the second NTP-I server synchronize the clock from the NTP-T server, and send the NTP SYNC signal as shown in FIG.
- Configure the NTP synchronization system service of the first NTP-I server and the second NTP-I server and provide an NTP server with a standard clock as the NTP-T server of the telecommunications.
- the configuration file of the first NTP-I server and the second NTP-I server are identical. And start the NTP process to synchronize the clock from NTP-T.
- first NTP-I server and the second NTP-I server provide clock synchronization for the service server and the set top box, as shown in the figure, NTP SYNC.
- Step S12 The first NTP-I server queries the first clock offset value of itself and the second NTP-I server according to the set time interval.
- the first NTP-I server sends a first clock deviation query request to the second NTP-I server according to the set query time interval, and receives the self and the first NTP-I server returning after receiving the first clock deviation query request.
- the first clock bias value of an NTP-I server is not limited to a configurable period of an NTP-I server.
- the first NTP-I server and the second NTP-I server are installed with a self-developed clock protection program (hereinafter referred to as NTP-PRO), and configure their own IP address and the IP address of the other party, and set a time difference threshold (referred to as LIMIT). ), for example, it can be 4S by default.
- NTP-PRO self-developed clock protection program
- LIMIT time difference threshold
- the first NTP-I server sends a clock deviation query request to the second NTP-I server and the second NTP-I server returns the clock offset value between itself and the first NTP-I server.
- Step S1.1 uses the "ntpdate -d ⁇ NTP-I-2 ⁇ " command to perform the clock deviation query, and step S1.2 returns the first clock offset value (OFFSET-REMOTE).
- Step S13 Determine whether the first clock deviation value exceeds a set time difference threshold. If yes, go to step S14; otherwise, go to step S22.
- the first clock offset value (OFFSET-REMOTE) is compared to the time difference threshold (LIMIT). When the first clock offset value (OFFSET-REMOTE) exceeds the time difference threshold (LIMIT), a subsequent query operation is performed, otherwise the clock is considered normal and no operation is performed.
- Step S14 The first NTP-I server queries the second clock offset of the NTP-T server.
- the first NTP-I server queries the second clock offset value of itself and the NTP-T server.
- the first NTP-I server sends a second clock deviation query request to the NTP-T server; and receives a second clock offset value between the NTP-T server and the first NTP-I server after receiving the second clock deviation query request. And its own standard clock; when the first NTP-I server determines that the second clock deviation value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock.
- Step S1.3 uses the "ntpdate -d ⁇ NTP-T ⁇ " command to perform clock deviation query.
- Step S1.4 returns the second clock offset value (OFFSET-SERVER) and the NTP-T server's own standard clock (referred to as SERVER for short).
- -TIME is the current time of the NTP-T server.
- Step S15 Determine whether the second clock deviation value exceeds the set time difference threshold.
- Step S16 Correct the local clock.
- the local clock is corrected.
- the local clock is considered abnormal, and the local clock is immediately corrected to be the same as SERVER-TIME; otherwise, the second NTP-I server clock is abnormal, the first NTP-I server Do nothing.
- Step S17 The second NTP-I server queries the third clock deviation value of itself and the first NTP-I server according to the set time interval.
- the second NTP-I server sends a third clock deviation query request to the first NTP-I server according to the set query time interval, and receives the first and the first NTP-I server returning after receiving the third clock deviation query request.
- the third clock offset value of the two NTP-I servers is not limited to the set query time interval.
- the first NTP-I server and the second NTP-I server are installed with a self-developed clock protection program (hereinafter referred to as NTP-PRO), and configure their own IP address and the IP address of the other party, and set a time difference threshold (referred to as LIMIT). ), for example, it can be 4S by default.
- NTP-PRO self-developed clock protection program
- LIMIT time difference threshold
- Step S2.1 uses the "ntpdate -d ⁇ NTP-I-1 ⁇ " command to perform a clock deviation query
- step S2.2 returns the first clock offset value (OFFSET-REMOTE).
- Step S18 It is judged whether the third clock deviation value exceeds the set time difference threshold. If yes, go to step S19; otherwise, go to step S22.
- the third clock offset value (OFFSET-REMOTE) is compared to the time difference threshold (LIMIT). When the third clock offset value (OFFSET-REMOTE) exceeds the time difference threshold (LIMIT), a subsequent query operation is performed, otherwise the clock is considered normal and no operation is performed.
- Step S19 The second NTP-I server queries the fourth clock offset between itself and the NTP-T server.
- the second NTP-I server queries the fourth clock deviation value of itself and the NTP-T server.
- the first NTP-I server sends a second clock deviation query request to the NTP-T server; receiving
- the second clock deviation value of the NTP-T server returned by the NTP-T server after receiving the second clock deviation query request and the first NTP-I server and the standard clock of the first NTP-I server; the first NTP-I server determines that the second clock deviation value exceeds the setting When the time difference threshold is set, the local clock is corrected according to the received standard clock.
- the second NTP-I server sends a clock deviation query request to the NTP-T server and the NTP-T server returns the clock offset value of itself and the second NTP-I server.
- Step S2.3 uses the "ntpdate -d ⁇ NTP-T ⁇ " command to perform clock deviation query.
- Step S2.4 returns the fourth clock offset value (OFFSET-SERVER) and the NTP-T server's own standard clock (referred to as SERVER for short).
- -TIME which is the current time of the NTP-T server.
- Step S20 Determine whether the fourth clock deviation value exceeds the set time difference threshold.
- Step S21 Correct the local clock.
- the local clock is corrected.
- the fourth clock offset value (OFFSET-SERVER) exceeds the time difference threshold (LIMIT)
- the local clock is considered abnormal, and the local clock is immediately corrected to be the same as SERVER-TIME; otherwise An NTP-I server clock is abnormal, and the second NTP-I server does nothing.
- the above method adds an NTP-I server to the IPTV system to complement the two NTP-I servers.
- the clock protection program is started in both NTP-I servers to protect and correct the clocks.
- two NTP-I servers can be one master and one standby, and for the set-top box, one of them can be selected as the server provided by the clock.
- the NTP server clock synchronization maintaining method and system are provided by the embodiment of the present invention.
- the NTP server is also provided.
- the structure of the NTP server is as shown in FIG. 4, and includes: a clock synchronization module 101, a first query module 102, and a Two query module 103.
- the clock synchronization module 101 is configured to synchronize the clock from the telecommunication NTP-T server.
- the first query module 102 is configured to query the first clock offset value of the second NTP-I server according to the set time interval.
- the second query module 103 is configured to query the second clock offset value of the self and the NTP-T server when the first clock offset value exceeds the set time difference threshold, and if the second clock offset value exceeds the set time difference threshold, Correct the local clock.
- the first query module 102 is specifically configured to: send a first clock deviation query request to the second NTP-I server according to the set query time interval; and receive the second NTP-I server to receive the first a first clock deviation value of the first NTP-I server returned by the clock deviation query request;
- the foregoing second query module 103 is specifically configured to: when the first clock deviation value exceeds the set time difference threshold, send a second clock deviation query request to the NTP-T server; and receive the NTP-T server receives the first After the second clock deviation query request, the second clock deviation value of the first NTP-I server and the standard clock of the first NTP-I server are returned; when the second clock deviation value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock. clock.
- the foregoing NTP server clock synchronization maintaining method and system provided by the embodiments of the present invention are applicable to When the NTP server is abnormal, the service of the NTP server is abnormal. This prevents the service of the NTP server from being abnormal. This prevents the abnormality of the clock of the NTP server as a single-point device. The system clock is garbled.
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Multimedia (AREA)
- Computer Networks & Wireless Communication (AREA)
- Electric Clocks (AREA)
- Synchronisation In Digital Transmission Systems (AREA)
Abstract
Disclosed are a method, system and device for keeping clock synchronization of NTP servers. A first NTP-I server and a second NTP-I server synchronize clocks from a telecommunication NTP-T server; the first NTP-I server inquires a first clock offset value between itself and the second NTP-I server according to a set time interval; the first NTP-I server inquires a second clock offset value between itself and the NTP-T server when the first clock offset value exceeds a set time difference threshold; and a local clock is corrected when the second clock offset value exceeds the set time difference threshold. The Method, system and device of the present invention can very well keep clock synchronization of NTP servers and avoid clock disorder of the system.
Description
NTP服务器时钟同步保持方法、 系统及装置 技术领域 NTP server clock synchronization maintaining method, system and device
本发明涉及网络电视技术领域,尤指一种 NTP( Network Time Protocol, 网络时间协议)服务器时钟同步保持方法、 系统及装置。 背景技术 The invention relates to the field of network television technology, in particular to a NTP (Network Time Protocol) server clock synchronization holding method, system and device. Background technique
交互式网络电视( Interactive Personality TV, IPTV )的众多业务流程都 依赖于时钟, 如时移业务、 回看业务、 订购业务等主要业务, 随着 IPTV的 迅猛发展, NTP服务器的压力也越来越大, 责任也越来越大。 NTP服务器 需要提供 IPTV各服务器的 NTP时钟同步, 也提供机顶盒( Set Top Box, STB ) 的 NTP时钟同步。 由于 STB开机后的时间默认为 1970年, 所以, NTP服务器的配置为不限制时差且仍然提供 NTP时钟同步服务。 Many business processes of Interactive Personality TV (IPTV) rely on clocks, such as time-shifted services, back-view services, and subscription services. With the rapid development of IPTV, the pressure on NTP servers is increasing. Big, the responsibility is getting bigger and bigger. The NTP server needs to provide NTP clock synchronization for each IPTV server, and also provides NTP clock synchronization for the Set Top Box (STB). Since the time after the STB is powered on defaults to 1970, the NTP server is configured to not limit the time difference and still provide the NTP clock synchronization service.
IPTV的 NTP服务器(以下简称为 NTP-I服务器 ) 配置从电信 NTP服 务器(以下简称为 NTP-T服务器)进行时钟同步, NTP-T服务器配置为如 果时差超过 4S则不提供 NTP同步服务。 具体组网架构参见图 1 , NTP-T月良 务器提供同步时钟, NTP-I服务器从 NTP-T服务器同步时钟信号, 实现时 钟同步, 并通过 NTP 同步(SYNC )信号同步各业务服务器和机顶盒的时 钟。 The NTP server of the IPTV (hereinafter referred to as the NTP-I server) is configured to synchronize the clock from the telecom NTP server (hereinafter referred to as the NTP-T server). The NTP-T server is configured to provide the NTP synchronization service if the time difference exceeds 4S. For the specific networking architecture, see Figure 1. The NTP-T server provides the synchronous clock. The NTP-I server synchronizes the clock signal from the NTP-T server to implement clock synchronization. The NTP synchronization (SYNC) signal is used to synchronize the service servers and set-top boxes. Clock.
如果 NTP-I服务器出现时钟跳变超过 4S, 则由于 NTP-T服务器配置, NTP-I服务器从 NTP-T服务器进行时钟同步的操作将会失败, NTP-I服务 器的错误时钟会通过它提供的 NTP服务同步到所有的 IPTV业务服务器和 STB, 导致业务服务器和 STB时钟出现错乱, 产生业务服务异常。
发明内容 If the NTP-I server has a clock transition of more than 4S, the NTP-I server will fail to perform clock synchronization from the NTP-T server due to the NTP-T server configuration. The NTP-I server's error clock will be provided through it. The NTP service is synchronized to all IPTV service servers and STBs, causing the service server and the STB clock to be disordered, resulting in abnormal service services. Summary of the invention
本发明实施例提供一种 NTP服务器时钟同步保持方法、 系统及装置, 用以解决现有 NTP服务器时钟同步失败时可能导致的系统时钟错乱和业务 服务异常的问题。 The embodiment of the invention provides a method, a system and a device for maintaining a clock synchronization of an NTP server, which are used to solve the problem that the system clock is disordered and the service service is abnormal when the clock synchronization of the existing NTP server fails.
为了解决上述问题, 本发明的技术方案是这样实现的: In order to solve the above problems, the technical solution of the present invention is implemented as follows:
一种网络时间协议 NTP服务器时钟同步保持方法, 包括: A network time protocol NTP server clock synchronization maintenance method, including:
第一 NTP-I服务器和第二 NTP-I服务器从电信 NTP-T服务器同步时钟; 第一 NTP-I服务器按照设定的时间间隔查询自身与第二 NTP-I服务器 的第一时钟偏差值, 当第一时钟偏差值超过设定的时差阈值时, 第一 NTP-I 服务器查询自身与 NTP-T服务器的第二时钟偏差值, 若第二时钟偏差值超 过设定的时差阈值, 则修正本地时钟; 并且, The first NTP-I server and the second NTP-I server synchronize the clock from the telecommunication NTP-T server; the first NTP-I server queries the first clock offset value of the second NTP-I server according to the set time interval. When the first clock deviation value exceeds the set time difference threshold, the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the local modification is corrected. Clock; and,
第二 NTP-I服务器按照设定的时间间隔查询自身与第一 NTP-I服务器 的第三时钟偏差值, 当第三时钟偏差值超过设定的时差阈值时, 第二 NTP-I 服务器查询自身与 NTP-T服务器的第四时钟偏差值, 若第四时钟偏差值超 过设定的时差阈值, 则修正本地时钟。 The second NTP-I server queries the third clock deviation value of the first NTP-I server according to the set time interval. When the third clock deviation value exceeds the set time difference threshold, the second NTP-I server queries itself. The fourth clock deviation value from the NTP-T server, if the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
其中, 第一 NTP-I服务器按照设定的时间间隔查询自身与第二 NTP-I 服务器的第一时钟偏差值, 包括: The first NTP-I server queries the first clock offset value between itself and the second NTP-I server according to the set time interval, including:
第一 NTP-I服务器按照设定的查询时间间隔向第二 NTP-I服务器发送 第一时钟偏差查询请求, 接收第二 NTP-I服务器在接收到所述第一时钟偏 差查询请求后返回的自身与第一 NTP-I服务器的第一时钟偏差值。 The first NTP-I server sends a first clock deviation query request to the second NTP-I server according to the set query time interval, and receives the second NTP-I server returns itself after receiving the first clock deviation query request. The first clock offset value from the first NTP-I server.
其中, 第二 NTP-I服务器按照设定的时间间隔查询自身与第一 NTP-I 服务器的第三时钟偏差值, 包括: The second NTP-I server queries the third clock offset value of the first NTP-I server according to the set time interval, including:
第二 NTP-I服务器按照设定的查询时间间隔向第一 NTP-I服务器发送 第三时钟偏差查询请求, 接收第一 NTP-I服务器在接收到所述第三时钟偏 差查询请求后返回的自身与第二 NTP-I服务器的第三时钟偏差值。
其中,第一 NTP-I服务器查询自身与 NTP-T服务器的第二时钟偏差值, 若第二时钟偏差值超过设定的时差阈值, 则修正本地时钟, 包括: The second NTP-I server sends a third clock deviation query request to the first NTP-I server according to the set query time interval, and receives the first NTP-I server returns itself after receiving the third clock deviation query request. The third clock deviation value from the second NTP-I server. The first NTP-I server queries the second clock offset value of the NTP-T server and the NTP-T server. If the second clock offset exceeds the set time difference threshold, the local clock is corrected, including:
第一 NTP-I服务器向 NTP-T服务器发送第二时钟偏差查询请求; 接收 NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第 一 NTP-I服务器的第二时钟偏差值和自身的标准时钟; The first NTP-I server sends a second clock deviation query request to the NTP-T server; and receives a second clock offset value between the NTP-T server and the first NTP-I server after receiving the second clock deviation query request. And its own standard clock;
第一 NTP-I服务器确定第二时钟偏差值超过设定的时差阈值时, 根据 接收到的标准时钟修正本地时钟。 When the first NTP-I server determines that the second clock offset value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock.
其中,第二 NTP-I服务器查询自身与 NTP-T服务器的第四时钟偏差值, 若第四时钟偏差值超过设定的时差阈值, 则修正本地时钟, 包括: The second NTP-I server queries the fourth clock offset value between itself and the NTP-T server. If the fourth clock offset value exceeds the set time difference threshold, the local clock is corrected, including:
第一 NTP-I服务器向 NTP-T服务器发送第二时钟偏差查询请求; 接收 NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第 一 NTP-I服务器的第二时钟偏差值和自身的标准时钟; The first NTP-I server sends a second clock deviation query request to the NTP-T server; and receives a second clock offset value between the NTP-T server and the first NTP-I server after receiving the second clock deviation query request. And its own standard clock;
第一 NTP-I服务器确定第二时钟偏差值超过设定的时差阈值时, 根据 接收到的标准时钟修正本地时钟。 When the first NTP-I server determines that the second clock offset value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock.
其中, 通过第一 NTP-I服务器和 /或第二 NTP-I服务器为业务服务器提 供时钟同步服务, 以及通过第一 NTP-I服务器或第二 NTP-I服务器为机顶 盒提供时钟同步服务。 The clock synchronization service is provided for the service server by using the first NTP-I server and/or the second NTP-I server, and the clock synchronization service is provided for the set top box by using the first NTP-I server or the second NTP-I server.
一种 NTP服务器时钟同步保持系统, 包括: An NTP server clock synchronization maintenance system includes:
第一 NTP-I服务器, 用于从电信 NTP-T服务器同步时钟; 按照设定的 时间间隔查询自身与第二 NTP-I服务器的第一时钟偏差值, 当第一时钟偏 差值超过设定的时差阈值时, 第一 NTP-I服务器查询自身与 NTP-T服务器 的第二时钟偏差值, 若第二时钟偏差值超过设定的时差阈值, 则修正本地 时钟; a first NTP-I server, configured to synchronize a clock from the telecommunication NTP-T server; query the first clock deviation value of the second NTP-I server according to the set time interval, when the first clock deviation value exceeds the set value When the time difference threshold is used, the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the local clock is corrected;
第二 NTP-I服务器, 用于从电信 NTP-T服务器同步时钟; 按照设定的 时间间隔查询自身与第一 NTP-I服务器的第三时钟偏差值, 当第三时钟偏
差值超过设定的时差阈值时, 第二 NTP-I服务器查询自身与 NTP-T服务器 的第四时钟偏差值, 若第四时钟偏差值超过设定的时差阈值, 则修正本地 时钟。 a second NTP-I server, configured to synchronize a clock from the telecommunication NTP-T server; query a third clock deviation value of the first NTP-I server according to the set time interval, when the third clock is biased When the difference exceeds the set time difference threshold, the second NTP-I server queries the fourth clock deviation value of itself and the NTP-T server, and if the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
其中, 所述第一 NTP-I服务器, 还用于为业务服务器和机顶盒提供时 钟同步服务; 所述第二 NTP-I服务器, 还用于为业务服务器提供时钟同步 服务和机顶盒提供时钟同步服务。 The first NTP-I server is further configured to provide a clock synchronization service for the service server and the set top box; and the second NTP-I server is further configured to provide a clock synchronization service for the service server and a clock synchronization service for the set top box.
一种 NTP服务器, 包括: An NTP server, including:
时钟同步模块, 用于从电信 NTP-T服务器同步时钟; a clock synchronization module, configured to synchronize a clock from a telecommunications NTP-T server;
第一查询模块, 用于按照设定的时间间隔查询自身与第二 NTP-I服务 器的第一时钟偏差值; a first query module, configured to query a first clock offset value of the second NTP-I server according to the set time interval;
第二查询模块, 用于当第一时钟偏差值超过设定的时差阈值时, 查询 自身与 NTP-T服务器的第二时钟偏差值, 若第二时钟偏差值超过设定的时 差阈值, 则修正本地时钟。 The second query module is configured to: when the first clock deviation value exceeds the set time difference threshold, query the second clock deviation value of the self and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the correction is performed. Local clock.
其中, 所述第一查询模块, 用于: The first query module is configured to:
按照设定的查询时间间隔向第二 NTP-I服务器发送第一时钟偏差查询 请求; 以及 Sending a first clock deviation query request to the second NTP-I server according to the set query interval;
接收第二 NTP-I服务器在接收到所述第一时钟偏差查询请求后返回的 自身与第一 NTP-I服务器的第一时钟偏差值。 Receiving a first clock offset value of the first NTP-I server returned by the second NTP-I server after receiving the first clock deviation query request and the first NTP-I server.
其中, 所述第二查询模块, 用于: The second query module is configured to:
当第一时钟偏差值超过设定的时差阈值时, 向 NTP-T服务器发送第二 时钟偏差查询请求; Sending a second clock deviation query request to the NTP-T server when the first clock deviation value exceeds the set time difference threshold;
接收 NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第 一 NTP-I服务器的第二时钟偏差值和自身的标准时钟; Receiving a second clock offset value of the NTP-T server and the first NTP-I server returned by the NTP-T server after receiving the second clock deviation query request and its own standard clock;
确定第二时钟偏差值超过设定的时差阈值时, 根据接收到的标准时钟 修正本地时钟。
本发明有益效果如下: When it is determined that the second clock deviation value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock. The beneficial effects of the present invention are as follows:
本发明实施例提供的 NTP服务器时钟同步保持方法、 系统及装置, 通 过第一 NTP-I服务器和第二 NTP-I服务器互相查询自身与对方的时钟偏差 值, 当第一 NTP-I服务器或第二 NTP-I服务器发现自身与对方的时钟偏差 超过设定的时差阈值时, 查询自身与 NTP-T服务器的时钟偏差值, 若自身 与 NTP-T服务器的时钟偏差值也超过设定的时差阈值, 则修正本地时钟。 从而避免了 NTP-I服务器的时钟同步失败和同步失败所导致业务服务器和 STB时钟出现错乱等问题, 确保了 NTP-I服务器的始终同步正常, 从而保 证了系统的时钟正确, 使系统能够正常运行。 附图说明 The NTP server clock synchronization holding method, system and device provided by the embodiment of the present invention, the first NTP-I server and the second NTP-I server mutually query each other's clock offset value, when the first NTP-I server or the first When the NTP-I server finds that the clock deviation between itself and the other party exceeds the set time difference threshold, it queries the clock offset value between itself and the NTP-T server. If the clock offset value between itself and the NTP-T server exceeds the set time difference threshold. , then correct the local clock. Therefore, the clock synchronization failure and the synchronization failure of the NTP-I server are avoided, which causes the service server and the STB clock to be disordered, ensuring that the NTP-I server is always synchronized, thereby ensuring that the clock of the system is correct and the system can operate normally. . DRAWINGS
图 1为现有技术中 IPTV系统组网架构图; 1 is a network diagram of an IPTV system in the prior art;
图 2为本发明实施例中 NTP服务器时钟同步保持系统的结构示意图; 图 3为本发明实施例中 NTP服务器时钟同步保持方法的流程图; 图 4为本发明实施例中 NTP服务器的结构示意图。 具体实施方式 2 is a schematic structural diagram of a clock synchronization and maintenance system of an NTP server according to an embodiment of the present invention; FIG. 3 is a flowchart of a method for maintaining a clock synchronization of an NTP server according to an embodiment of the present invention; and FIG. 4 is a schematic structural diagram of an NTP server according to an embodiment of the present invention. detailed description
本发明实施例提供一种 NTP服务器时钟同步保持方法, 通过如图 2所 示的 NTP服务器时钟同步保持系统实现,该系统包括:第一 NTP-I服务器、 第二 NTP-I服务器和电信 NTP-T服务器。 An embodiment of the present invention provides a method for maintaining a clock synchronization of an NTP server, which is implemented by using an NTP server clock synchronization and maintenance system as shown in FIG. 2, where the system includes: a first NTP-I server, a second NTP-I server, and a telecommunications NTP- T server.
第一 NTP-I服务器, 用于从电信 NTP-T服务器同步时钟; 按照设定的 时间间隔查询自身与第二 NTP-I服务器的第一时钟偏差值, 当第一时钟偏 差值超过设定的时差阈值时, 第一 NTP-I服务器查询自身与 NTP-T服务器 的第二时钟偏差值, 若第二时钟偏差值超过设定的时差阈值, 则修正本地 时钟。 a first NTP-I server, configured to synchronize a clock from the telecommunication NTP-T server; query the first clock deviation value of the second NTP-I server according to the set time interval, when the first clock deviation value exceeds the set value When the time difference threshold is reached, the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the local clock is corrected.
第二 NTP-I服务器, 用于从电信 NTP-T服务器同步时钟; 按照设定的
时间间隔查询自身与第一 NTP-I服务器的第三时钟偏差值, 当第三时钟偏 差值超过设定的时差阈值时, 第二 NTP-I服务器查询自身与 NTP-T服务器 的第四时钟偏差值, 若第四时钟偏差值超过设定的时差阈值, 则修正本地 时钟。 a second NTP-I server for synchronizing the clock from the telecommunications NTP-T server; The time interval queries the third clock deviation value of the first NTP-I server. When the third clock deviation value exceeds the set time difference threshold, the second NTP-I server queries the fourth clock deviation of the NTP-T server. Value, if the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
上述系统还包括若干业务服务和机顶盒。 其中, 第一 NTP-I服务器, 还用于为业务服务器和机顶盒提供时钟同步服务; 第二 NTP-I服务器, 还 用于为业务服务器提供时钟同步服务和机顶盒提供时钟同步服务。 The above system also includes several business services and set top boxes. The first NTP-I server is further configured to provide a clock synchronization service for the service server and the set top box; and the second NTP-I server is further configured to provide a clock synchronization service for the service server and a clock synchronization service for the set top box.
具体的通过第一 NTP-I服务器和 /或第二 NTP-I服务器为业务服务器提 供时钟同步服务, 以及通过第一 NTP-I服务器或第二 NTP-I服务器为机顶 盒提供时钟同步服务。 Specifically, the first NTP-I server and/or the second NTP-I server provide clock synchronization services for the service server, and the clock synchronization service is provided for the set top box through the first NTP-I server or the second NTP-I server.
本发明实施例提供的 NTP服务器时钟同步保持方法, 其流程如图 3所 示, 包括如下步驟: The method for maintaining the clock synchronization of the NTP server provided by the embodiment of the present invention is as shown in FIG. 3, and includes the following steps:
步驟 S11 : 第一 NTP-I服务器和第二 NTP-I服务器从电信 NTP-T服务 器同步时钟。 Step S11: The first NTP-I server and the second NTP-I server synchronize the clock from the telecommunication NTP-T server.
参见图 1中所示的步驟 0.1和步驟 0.2,第一 NTP-I服务器和第二 NTP-I 服务器从 NTP-T服务器同步时钟, 如图 2 中所示的发送 NTP同步(NTP SYNC )信号。 Referring to steps 0.1 and 0.2 shown in Fig. 1, the first NTP-I server and the second NTP-I server synchronize the clock from the NTP-T server, and send the NTP SYNC signal as shown in FIG.
配置第一 NTP-I服务器和第二 NTP-I服务器的 NTP同步系统服务, 且 提供标准时钟的 NTP服务器为电信的 NTP-T服务器。配置第一 NTP-I服务 器和第二 NTP-I服务器的配置文件完全相同。 并启动 NTP进程, 从 NTP-T 进行时钟同步。 Configure the NTP synchronization system service of the first NTP-I server and the second NTP-I server, and provide an NTP server with a standard clock as the NTP-T server of the telecommunications. The configuration file of the first NTP-I server and the second NTP-I server are identical. And start the NTP process to synchronize the clock from NTP-T.
此外第一 NTP-I服务器和第二 NTP-I服务器为业务服务器和机顶盒提 供时钟同步, 如图中所示的 NTP SYNC。 In addition, the first NTP-I server and the second NTP-I server provide clock synchronization for the service server and the set top box, as shown in the figure, NTP SYNC.
步驟 S12: 第一 NTP-I服务器按照设定的时间间隔查询自身与第二 NTP-I服务器的第一时钟偏差值。
第一 NTP-I服务器按照设定的查询时间间隔向第二 NTP-I服务器发送 第一时钟偏差查询请求, 接收第二 NTP-I服务器在接收到第一时钟偏差查 询请求后返回的自身与第一 NTP-I服务器的第一时钟偏差值。 Step S12: The first NTP-I server queries the first clock offset value of itself and the second NTP-I server according to the set time interval. The first NTP-I server sends a first clock deviation query request to the second NTP-I server according to the set query time interval, and receives the self and the first NTP-I server returning after receiving the first clock deviation query request. The first clock bias value of an NTP-I server.
参见图 2,其中,第一 NTP-I服务器和第二 NTP-I服务器安装自研时钟 保护程序(以下简称 NTP-PRO ), 并配置自身 IP地址和对方的 IP地址, 设 置时差阈值(简称 LIMIT ), 例如可以默认为 4S。 启动 NTP-PRO进程, 此 进程为常驻进程, 每 10秒执行一次, 10秒即为设定的时间间隔。 Referring to FIG. 2, the first NTP-I server and the second NTP-I server are installed with a self-developed clock protection program (hereinafter referred to as NTP-PRO), and configure their own IP address and the IP address of the other party, and set a time difference threshold (referred to as LIMIT). ), for example, it can be 4S by default. Start the NTP-PRO process, which is a resident process, executed every 10 seconds, and 10 seconds is the set time interval.
参见图 1的步驟 1.1和步驟 1.2分别为第一 NTP-I服务器向第二 NTP-I 服务器发送时钟偏差查询请求和第二 NTP-I服务器返回自身与第一 NTP-I 服务器的时钟偏差值。 步驟 S1.1使用 "ntpdate -d {NTP-I-2}" 命令进行时 钟偏差查询, 步驟 S1.2返回的是第一时钟偏差值( OFFSET-REMOTE )。 Referring to steps 1.1 and 1.2 of FIG. 1, the first NTP-I server sends a clock deviation query request to the second NTP-I server and the second NTP-I server returns the clock offset value between itself and the first NTP-I server. Step S1.1 uses the "ntpdate -d {NTP-I-2}" command to perform the clock deviation query, and step S1.2 returns the first clock offset value (OFFSET-REMOTE).
步驟 S13: 判断第一时钟偏差值是否超过设定的时差阈值。 若是, 执行 步驟 S14; 否则执行步驟 S22。 Step S13: Determine whether the first clock deviation value exceeds a set time difference threshold. If yes, go to step S14; otherwise, go to step S22.
将第一时钟偏差值(OFFSET-REMOTE )与时差阈值(LIMIT )进行比 较。 当第一时钟偏差值 ( OFFSET-REMOTE )超过时差阈值( LIMIT )执行 后续查询操作, 否则认为时钟是正常的, 不执行操作。 The first clock offset value (OFFSET-REMOTE) is compared to the time difference threshold (LIMIT). When the first clock offset value (OFFSET-REMOTE) exceeds the time difference threshold (LIMIT), a subsequent query operation is performed, otherwise the clock is considered normal and no operation is performed.
步驟 S14: 第一 NTP-I服务器查询自身与 NTP-T服务器的第二时钟偏 差值。 Step S14: The first NTP-I server queries the second clock offset of the NTP-T server.
当第一时钟偏差值超过设定的时差阈值时, 第一 NTP-I服务器查询自 身与 NTP-T服务器的第二时钟偏差值。 When the first clock offset value exceeds the set time difference threshold, the first NTP-I server queries the second clock offset value of itself and the NTP-T server.
第一 NTP-I服务器向 NTP-T服务器发送第二时钟偏差查询请求; 接收 NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第一 NTP-I 服务器的第二时钟偏差值和自身的标准时钟; 第一 NTP-I服务器确定第二 时钟偏差值超过设定的时差阈值时, 根据接收到的标准时钟修正本地时钟。 The first NTP-I server sends a second clock deviation query request to the NTP-T server; and receives a second clock offset value between the NTP-T server and the first NTP-I server after receiving the second clock deviation query request. And its own standard clock; when the first NTP-I server determines that the second clock deviation value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock.
参见图 1的步驟 1.3和步驟 1.4分别为第一 NTP-I服务器向 NTP-T服务
器发送时钟偏差查询请求和 NTP-T服务器返回自身与第一 NTP-I服务器的 时钟偏差值。 步驟 S1.3使用 "ntpdate -d {NTP-T}"命令进行时钟偏差查询, 步驟 S1.4返回的是第二时钟偏差值( OFFSET-SERVER )和 NTP-T服务器 自身标准时钟(简称为 SERVER-TIME ) , 即 NTP-T服务器当前时间。 See steps 1.3 and 1.4 of Figure 1 for the first NTP-I server to serve NTP-T. The device sends a clock deviation query request and the NTP-T server returns its own clock offset value from the first NTP-I server. Step S1.3 uses the "ntpdate -d {NTP-T}" command to perform clock deviation query. Step S1.4 returns the second clock offset value (OFFSET-SERVER) and the NTP-T server's own standard clock (referred to as SERVER for short). -TIME ) , which is the current time of the NTP-T server.
步驟 S15: 判断第二时钟偏差值是否超过设定的时差阈值。 Step S15: Determine whether the second clock deviation value exceeds the set time difference threshold.
比较第二时钟偏差值( OFFSET-SERVER )是否超过时差阈值( LIMIT )。 若是, 执行步驟 S16; 否则执行步驟 S22。 Compares whether the second clock deviation value (OFFSET-SERVER) exceeds the time difference threshold (LIMIT). If yes, go to step S16; otherwise, go to step S22.
步驟 S16: 修正本地时钟。 Step S16: Correct the local clock.
若第二时钟偏差值超过设定的时差阈值, 则修正本地时钟。 If the second clock offset value exceeds the set time difference threshold, the local clock is corrected.
如果第二时钟偏差值 ( OFFSET-SERVER )超过时差阈值( LIMIT ), 认 为本地时钟异常, 立即修正本地时钟与 SERVER-TIME相同; 否则认为第 二 NTP-I服务器时钟异常, 第一 NTP-I服务器不做任何操作。 If the second clock offset value (OFFSET-SERVER) exceeds the time difference threshold (LIMIT), the local clock is considered abnormal, and the local clock is immediately corrected to be the same as SERVER-TIME; otherwise, the second NTP-I server clock is abnormal, the first NTP-I server Do nothing.
步驟 S17: 第二 NTP-I服务器按照设定的时间间隔查询自身与第一 NTP-I服务器的第三时钟偏差值。 Step S17: The second NTP-I server queries the third clock deviation value of itself and the first NTP-I server according to the set time interval.
第二 NTP-I服务器按照设定的查询时间间隔向第一 NTP-I服务器发送 第三时钟偏差查询请求, 接收第一 NTP-I服务器在接收到第三时钟偏差查 询请求后返回的自身与第二 NTP-I服务器的第三时钟偏差值。 The second NTP-I server sends a third clock deviation query request to the first NTP-I server according to the set query time interval, and receives the first and the first NTP-I server returning after receiving the third clock deviation query request. The third clock offset value of the two NTP-I servers.
参见图 2,其中,第一 NTP-I服务器和第二 NTP-I服务器安装自研时钟 保护程序(以下简称 NTP-PRO ), 并配置自身 IP地址和对方的 IP地址, 设 置时差阈值(简称 LIMIT ), 例如可以默认为 4S。 启动 NTP-PRO进程, 此 进程为常驻进程, 每 10秒执行一次, 10秒即为设定的时间间隔。 Referring to FIG. 2, the first NTP-I server and the second NTP-I server are installed with a self-developed clock protection program (hereinafter referred to as NTP-PRO), and configure their own IP address and the IP address of the other party, and set a time difference threshold (referred to as LIMIT). ), for example, it can be 4S by default. Start the NTP-PRO process, which is a resident process, executed every 10 seconds, and 10 seconds is the set time interval.
参见图 1的步驟 2.1和步驟 2.2分别为第二 NTP-I服务器向第一 NTP-I 服务器发送时钟偏差查询请求和第一 NTP-I服务器返回自身与第二 NTP-I 服务器的时钟偏差值。 步驟 S2.1使用 "ntpdate -d {NTP-I-1 }" 命令进行时 钟偏差查询, 步驟 S2.2返回的是第一时钟偏差值( OFFSET-REMOTE )。
步驟 S18: 判断第三时钟偏差值是否超过设定的时差阈值。 若是, 执行 步驟 S19; 否则执行步驟 S22。 Referring to steps 2.1 and 2.2 of FIG. 1, respectively, the second NTP-I server sends a clock deviation query request to the first NTP-I server and a clock offset value of the first NTP-I server returning itself and the second NTP-I server. Step S2.1 uses the "ntpdate -d {NTP-I-1 }" command to perform a clock deviation query, and step S2.2 returns the first clock offset value (OFFSET-REMOTE). Step S18: It is judged whether the third clock deviation value exceeds the set time difference threshold. If yes, go to step S19; otherwise, go to step S22.
将第三时钟偏差值(OFFSET-REMOTE )与时差阈值(LIMIT )进行比 较。 当第三时钟偏差值 ( OFFSET-REMOTE )超过时差阈值 ( LIMIT )执行 后续查询操作, 否则认为时钟是正常的, 不执行操作。 The third clock offset value (OFFSET-REMOTE) is compared to the time difference threshold (LIMIT). When the third clock offset value (OFFSET-REMOTE) exceeds the time difference threshold (LIMIT), a subsequent query operation is performed, otherwise the clock is considered normal and no operation is performed.
步驟 S19: 第二 NTP-I服务器查询自身与 NTP-T服务器的第四时钟偏 差值。 Step S19: The second NTP-I server queries the fourth clock offset between itself and the NTP-T server.
当第三时钟偏差值超过设定的时差阈值时, 第二 NTP-I服务器查询自 身与 NTP-T服务器的第四时钟偏差值。 When the third clock deviation value exceeds the set time difference threshold, the second NTP-I server queries the fourth clock deviation value of itself and the NTP-T server.
第一 NTP-I服务器向 NTP-T服务器发送第二时钟偏差查询请求; 接收 The first NTP-I server sends a second clock deviation query request to the NTP-T server; receiving
NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第一 NTP-I 服务器的第二时钟偏差值和自身的标准时钟; 第一 NTP-I服务器确定第二 时钟偏差值超过设定的时差阈值时, 根据接收到的标准时钟修正本地时钟。 The second clock deviation value of the NTP-T server returned by the NTP-T server after receiving the second clock deviation query request and the first NTP-I server and the standard clock of the first NTP-I server; the first NTP-I server determines that the second clock deviation value exceeds the setting When the time difference threshold is set, the local clock is corrected according to the received standard clock.
参见图 2的步驟 2.3和步驟 2.4分别为第二 NTP-I服务器向 NTP-T服务 器发送时钟偏差查询请求和 NTP-T服务器返回自身与第二 NTP-I服务器的 时钟偏差值。 步驟 S2.3使用 "ntpdate -d {NTP-T}"命令进行时钟偏差查询, 步驟 S2.4返回的是第四时钟偏差值( OFFSET-SERVER )和 NTP-T服务器 自身标准时钟(简称为 SERVER-TIME ) , 即 NTP-T服务器当前时间。 Referring to steps 2.3 and 2.4 of Figure 2, the second NTP-I server sends a clock deviation query request to the NTP-T server and the NTP-T server returns the clock offset value of itself and the second NTP-I server. Step S2.3 uses the "ntpdate -d {NTP-T}" command to perform clock deviation query. Step S2.4 returns the fourth clock offset value (OFFSET-SERVER) and the NTP-T server's own standard clock (referred to as SERVER for short). -TIME ) , which is the current time of the NTP-T server.
步驟 S20: 判断第四时钟偏差值是否超过设定的时差阈值。 Step S20: Determine whether the fourth clock deviation value exceeds the set time difference threshold.
比较第四时钟偏差值 ( OFFSET-SERVER )是否超过时差阈值( LIMIT )。 若是, 执行步驟 S21 ; 否则执行步驟 S22。 Compares whether the fourth clock deviation value (OFFSET-SERVER) exceeds the time difference threshold (LIMIT). If yes, go to step S21; otherwise, go to step S22.
步驟 S21 : 修正本地时钟。 Step S21: Correct the local clock.
若第四时钟偏差值超过设定的时差阈值, 则修正本地时钟。 If the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
如果第四时钟偏差值 ( OFFSET-SERVER )超过时差阈值( LIMIT ), 认 为本地时钟异常, 立即修正本地时钟与 SERVER-TIME相同; 否则认为第
一 NTP-I服务器时钟异常, 第二 NTP-I服务器不做任何操作。 If the fourth clock offset value (OFFSET-SERVER) exceeds the time difference threshold (LIMIT), the local clock is considered abnormal, and the local clock is immediately corrected to be the same as SERVER-TIME; otherwise An NTP-I server clock is abnormal, and the second NTP-I server does nothing.
步驟 S22: 结束。 Step S22: End.
上述方法在 IPTV系统中增设一台 NTP-I服务器,实现两台 NTP-I服务 器互补。 在两台 NTP-I服务器中均启动时钟保护程序, 实现时钟的互相保 护与修正。 对业务服务器而言, 两台 NTP-I服务器可以一主一备, 对于机 顶盒则选择其中一台作为时钟提供的服务器即可。 The above method adds an NTP-I server to the IPTV system to complement the two NTP-I servers. The clock protection program is started in both NTP-I servers to protect and correct the clocks. For the service server, two NTP-I servers can be one master and one standby, and for the set-top box, one of them can be selected as the server provided by the clock.
基于本发明实施例提供的上述 NTP服务器时钟同步保持方法和系统, 本发明实施例还提供一种 NTP服务器, 其结构如图 4所示, 包括: 时钟同 步模块 101、 第一查询模块 102和第二查询模块 103。 The NTP server clock synchronization maintaining method and system are provided by the embodiment of the present invention. The NTP server is also provided. The structure of the NTP server is as shown in FIG. 4, and includes: a clock synchronization module 101, a first query module 102, and a Two query module 103.
时钟同步模块 101 , 用于从电信 NTP-T服务器同步时钟。 The clock synchronization module 101 is configured to synchronize the clock from the telecommunication NTP-T server.
第一查询模块 102, 用于按照设定的时间间隔查询自身与第二 NTP-I 服务器的第一时钟偏差值. The first query module 102 is configured to query the first clock offset value of the second NTP-I server according to the set time interval.
第二查询模块 103 , 用于当第一时钟偏差值超过设定的时差阈值时, 查 询自身与 NTP-T服务器的第二时钟偏差值, 若第二时钟偏差值超过设定的 时差阈值, 则修正本地时钟。 The second query module 103 is configured to query the second clock offset value of the self and the NTP-T server when the first clock offset value exceeds the set time difference threshold, and if the second clock offset value exceeds the set time difference threshold, Correct the local clock.
优选的, 上述第一查询模块 102, 具体用于: 按照设定的查询时间间隔 向第二 NTP-I服务器发送第一时钟偏差查询请求; 以及接收第二 NTP-I服 务器在接收到所述第一时钟偏差查询请求后返回的自身与第一 NTP-I服务 器的第一时钟偏差值; Preferably, the first query module 102 is specifically configured to: send a first clock deviation query request to the second NTP-I server according to the set query time interval; and receive the second NTP-I server to receive the first a first clock deviation value of the first NTP-I server returned by the clock deviation query request;
优选的, 上述第二查询模块 103 , 具体用于: 当第一时钟偏差值超过设 定的时差阈值时,向 NTP-T服务器发送第二时钟偏差查询请求;接收 NTP-T 服务器在接收到第二时钟偏差查询请求后返回的自身与第一 NTP-I服务器 的第二时钟偏差值和自身的标准时钟; 确定第二时钟偏差值超过设定的时 差阈值时, 根据接收到的标准时钟修正本地时钟。 Preferably, the foregoing second query module 103 is specifically configured to: when the first clock deviation value exceeds the set time difference threshold, send a second clock deviation query request to the NTP-T server; and receive the NTP-T server receives the first After the second clock deviation query request, the second clock deviation value of the first NTP-I server and the standard clock of the first NTP-I server are returned; when the second clock deviation value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock. clock.
本发明实施例提供的上述 NTP服务器时钟同步保持方法和系统适用于
NTP服务器异常时的保护, 确保在 NTP服务器异常时不会导致业务服务异 常, 有效的避免了 NTP服务器作为单点设备所存在的时钟异常的隐患, 避 免了由于 NTP时钟跳变导致业务服务异常和系统时钟错乱。 The foregoing NTP server clock synchronization maintaining method and system provided by the embodiments of the present invention are applicable to When the NTP server is abnormal, the service of the NTP server is abnormal. This prevents the service of the NTP server from being abnormal. This prevents the abnormality of the clock of the NTP server as a single-point device. The system clock is garbled.
以上所述, 仅为本发明的较佳实施例而已, 并非用于限定本发明的保 护范围。
The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention.
Claims
1、 一种网络时间协议 NTP服务器时钟同步保持方法, 包括: 第一 NTP-I服务器和第二 NTP-I服务器从电信 NTP-T服务器同步时钟; 第一 NTP-I服务器按照设定的时间间隔查询自身与第二 NTP-I服务器 的第一时钟偏差值, 当第一时钟偏差值超过设定的时差阈值时, 第一 NTP-I 服务器查询自身与 NTP-T服务器的第二时钟偏差值, 若第二时钟偏差值超 过设定的时差阈值, 则修正本地时钟; 并且, A network time protocol NTP server clock synchronization maintaining method, comprising: a first NTP-I server and a second NTP-I server synchronizing a clock from a telecommunication NTP-T server; the first NTP-I server is at a set time interval Querying a first clock offset value between the self and the second NTP-I server, and when the first clock offset value exceeds the set time difference threshold, the first NTP-I server queries the second clock offset value of the NTP-T server, Correcting the local clock if the second clock deviation value exceeds the set time difference threshold; and
第二 NTP-I服务器按照设定的时间间隔查询自身与第一 NTP-I服务器 的第三时钟偏差值, 当第三时钟偏差值超过设定的时差阈值时, 第二 NTP-I 服务器查询自身与 NTP-T服务器的第四时钟偏差值, 若第四时钟偏差值超 过设定的时差阈值, 则修正本地时钟。 The second NTP-I server queries the third clock deviation value of the first NTP-I server according to the set time interval. When the third clock deviation value exceeds the set time difference threshold, the second NTP-I server queries itself. The fourth clock deviation value from the NTP-T server, if the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected.
2、 如权利要求 1所述的方法, 其中, 第一 NTP-I服务器按照设定的时 间间隔查询自身与第二 NTP-I服务器的第一时钟偏差值, 包括: The method of claim 1, wherein the first NTP-I server queries the first clock offset value of the second NTP-I server according to the set time interval, including:
第一 NTP-I服务器按照设定的查询时间间隔向第二 NTP-I服务器发送 第一时钟偏差查询请求, 接收第二 NTP-I服务器在接收到所述第一时钟偏 差查询请求后返回的自身与第一 NTP-I服务器的第一时钟偏差值。 The first NTP-I server sends a first clock deviation query request to the second NTP-I server according to the set query time interval, and receives the second NTP-I server returns itself after receiving the first clock deviation query request. The first clock offset value from the first NTP-I server.
3、 如权利要求 1所述的方法, 其中, 第二 NTP-I服务器按照设定的时 间间隔查询自身与第一 NTP-I服务器的第三时钟偏差值, 包括: The method of claim 1, wherein the second NTP-I server queries the third clock offset value of the first NTP-I server according to the set time interval, including:
第二 NTP-I服务器按照设定的查询时间间隔向第一 NTP-I服务器发送 第三时钟偏差查询请求, 接收第一 NTP-I服务器在接收到所述第三时钟偏 差查询请求后返回的自身与第二 NTP-I服务器的第三时钟偏差值。 The second NTP-I server sends a third clock deviation query request to the first NTP-I server according to the set query time interval, and receives the first NTP-I server returns itself after receiving the third clock deviation query request. The third clock deviation value from the second NTP-I server.
4、 如权利要求 1 所述的方法, 其中, 第一 NTP-I服务器查询自身与 NTP-T服务器的第二时钟偏差值, 若第二时钟偏差值超过设定的时差阈值, 则修正本地时钟, 包括: 4. The method according to claim 1, wherein the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, corrects the local clock. , including:
第一 NTP-I服务器向 NTP-T服务器发送第二时钟偏差查询请求; 接收 NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第 一 NTP-I服务器的第二时钟偏差值和自身的标准时钟; The first NTP-I server sends a second clock deviation query request to the NTP-T server; Receiving a second clock deviation value of the NTP-T server and the first NTP-I server returned by the NTP-T server after receiving the second clock deviation query request and its own standard clock;
第一 NTP-I服务器确定第二时钟偏差值超过设定的时差阈值时, 根据 接收到的标准时钟修正本地时钟。 When the first NTP-I server determines that the second clock offset value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock.
5、 如权利要求 1 所述的方法, 其中, 第二 NTP-I服务器查询自身与 5. The method of claim 1, wherein the second NTP-I server queries itself and
NTP-T服务器的第四时钟偏差值, 若第四时钟偏差值超过设定的时差阈值, 则修正本地时钟, 包括: The fourth clock deviation value of the NTP-T server. If the fourth clock deviation value exceeds the set time difference threshold, the local clock is corrected, including:
第一 NTP-I服务器向 NTP-T服务器发送第二时钟偏差查询请求; 接收 NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第 一 NTP-I服务器的第二时钟偏差值和自身的标准时钟; The first NTP-I server sends a second clock deviation query request to the NTP-T server; and receives a second clock offset value between the NTP-T server and the first NTP-I server after receiving the second clock deviation query request. And its own standard clock;
第一 NTP-I服务器确定第二时钟偏差值超过设定的时差阈值时, 根据 接收到的标准时钟修正本地时钟。 When the first NTP-I server determines that the second clock offset value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock.
6、 如权利要求 1至 5任一项所述的方法, 其中, 通过第一 NTP-I服务 器和 /或第二 NTP-I服务器为业务服务器提供时钟同步服务, 以及通过第一 NTP-I服务器或第二 NTP-I服务器为机顶盒提供时钟同步服务。 The method according to any one of claims 1 to 5, wherein the clock synchronization service is provided to the service server by the first NTP-I server and/or the second NTP-I server, and the first NTP-I server is used. Or the second NTP-I server provides clock synchronization services for the set top box.
7、 一种 NTP服务器时钟同步保持系统, 包括: 7. An NTP server clock synchronization maintaining system, comprising:
第一 NTP-I服务器, 用于从电信 NTP-T服务器同步时钟; 按照设定的 时间间隔查询自身与第二 NTP-I服务器的第一时钟偏差值, 当第一时钟偏 差值超过设定的时差阈值时, 第一 NTP-I服务器查询自身与 NTP-T服务器 的第二时钟偏差值, 若第二时钟偏差值超过设定的时差阈值, 则修正本地 时钟; a first NTP-I server, configured to synchronize a clock from the telecommunication NTP-T server; query the first clock deviation value of the second NTP-I server according to the set time interval, when the first clock deviation value exceeds the set value When the time difference threshold is used, the first NTP-I server queries the second clock deviation value of itself and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the local clock is corrected;
第二 NTP-I服务器, 用于从电信 NTP-T服务器同步时钟; 按照设定的 时间间隔查询自身与第一 NTP-I服务器的第三时钟偏差值, 当第三时钟偏 差值超过设定的时差阈值时, 第二 NTP-I服务器查询自身与 NTP-T服务器 的第四时钟偏差值, 若第四时钟偏差值超过设定的时差阈值, 则修正本地 时钟。 a second NTP-I server, configured to synchronize a clock from the telecommunication NTP-T server; query a third clock deviation value of the first NTP-I server according to the set time interval, when the third clock deviation value exceeds the set value When the time difference threshold is used, the second NTP-I server queries the fourth clock deviation value of itself and the NTP-T server, and if the fourth clock deviation value exceeds the set time difference threshold, the local modification is corrected. Clock.
8、 如权利要求 7所述的系统, 其中, 所述第一 NTP-I服务器, 还用于 为业务服务器和机顶盒提供时钟同步服务; 所述第二 NTP-I服务器, 还用 于为业务服务器提供时钟同步服务和机顶盒提供时钟同步服务。 The system of claim 7, wherein the first NTP-I server is further configured to provide a clock synchronization service for the service server and the set top box; the second NTP-I server is further configured to be a service server. Clock synchronization service and set-top box provide clock synchronization service.
9、 一种 NTP服务器, 包括: 9. An NTP server, including:
时钟同步模块, 用于从电信 NTP-T服务器同步时钟; a clock synchronization module, configured to synchronize a clock from a telecommunications NTP-T server;
第一查询模块, 用于按照设定的时间间隔查询自身与第二 NTP-I服务 器的第一时钟偏差值; a first query module, configured to query a first clock offset value of the second NTP-I server according to the set time interval;
第二查询模块, 用于当第一时钟偏差值超过设定的时差阈值时, 查询 自身与 NTP-T服务器的第二时钟偏差值, 若第二时钟偏差值超过设定的时 差阈值, 则修正本地时钟。 The second query module is configured to: when the first clock deviation value exceeds the set time difference threshold, query the second clock deviation value of the self and the NTP-T server, and if the second clock deviation value exceeds the set time difference threshold, the correction is performed. Local clock.
10、 如权利要求 9所述的 NTP服务器, 其中, 所述第一查询模块, 用 于: The NTP server according to claim 9, wherein the first query module is used to:
按照设定的查询时间间隔向第二 NTP-I服务器发送第一时钟偏差查询 请求; 以及 Sending a first clock deviation query request to the second NTP-I server according to the set query interval;
接收第二 NTP-I服务器在接收到所述第一时钟偏差查询请求后返回的 自身与第一 NTP-I服务器的第一时钟偏差值。 Receiving a first clock offset value of the first NTP-I server returned by the second NTP-I server after receiving the first clock deviation query request and the first NTP-I server.
11、 如权利要求 10或 11所述的 NTP服务器, 其中, 所述第二查询模 块, 用于: The NTP server according to claim 10 or 11, wherein the second query module is configured to:
当第一时钟偏差值超过设定的时差阈值时, 向 NTP-T服务器发送第二 时钟偏差查询请求; Sending a second clock deviation query request to the NTP-T server when the first clock deviation value exceeds the set time difference threshold;
接收 NTP-T服务器在接收到第二时钟偏差查询请求后返回的自身与第 一 NTP-I服务器的第二时钟偏差值和自身的标准时钟; Receiving a second clock offset value of the NTP-T server and the first NTP-I server returned by the NTP-T server after receiving the second clock deviation query request and its own standard clock;
确定第二时钟偏差值超过设定的时差阈值时, 根据接收到的标准时钟 修正本地时钟。 When it is determined that the second clock deviation value exceeds the set time difference threshold, the local clock is corrected according to the received standard clock.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201110166074.9 | 2011-06-20 | ||
CN201110166074.9A CN102231656B (en) | 2011-06-20 | 2011-06-20 | Ntp server clock synchronization keeping method, system and device |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2012174892A1 true WO2012174892A1 (en) | 2012-12-27 |
Family
ID=44844198
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/CN2012/072259 WO2012174892A1 (en) | 2011-06-20 | 2012-03-13 | Method, system and device for keeping clock synchronization of ntp servers |
Country Status (2)
Country | Link |
---|---|
CN (1) | CN102231656B (en) |
WO (1) | WO2012174892A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2020155738A1 (en) * | 2019-01-28 | 2020-08-06 | Telefonaktiebolaget Lm Ericsson (Publ) | Clock distribution method and apparatus in network |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102231656B (en) * | 2011-06-20 | 2016-09-14 | 南京中兴新软件有限责任公司 | Ntp server clock synchronization keeping method, system and device |
CN102664697A (en) * | 2012-04-05 | 2012-09-12 | 中兴通讯股份有限公司 | Network clock synchronization system and method thereof |
CN102916799A (en) * | 2012-11-09 | 2013-02-06 | 四川长虹电子系统有限公司 | Method for time synchronization of network time protocol (NTP) server |
CN103763056A (en) * | 2013-12-31 | 2014-04-30 | 电信科学技术第五研究所 | Method for time synchronization high-precision remote monitoring |
CN105812854B (en) * | 2014-12-30 | 2019-07-19 | Tcl集团股份有限公司 | A kind of control method and device that advertisement plays |
CN106231371B (en) * | 2016-07-27 | 2019-07-02 | 青岛海信电器股份有限公司 | Method for synchronizing time, TV and EPG server |
CN108234057A (en) * | 2018-01-24 | 2018-06-29 | 郑州云海信息技术有限公司 | Method for synchronizing time, device and the storage medium of server based on BMC |
CN109634353A (en) * | 2018-12-03 | 2019-04-16 | 郑州云海信息技术有限公司 | Server host cascades BOX topological structure clock synchronizing method, device, terminal and storage medium |
CN109687929B (en) * | 2018-12-11 | 2020-08-18 | 苏州浪潮智能科技有限公司 | Method for realizing HOST-BOX multi-stage cascade server time synchronization |
CN111381486B (en) * | 2018-12-28 | 2022-02-08 | 北京金风科创风电设备有限公司 | Controller timing method and device, controller and wind generating set |
CN112104433A (en) * | 2019-06-18 | 2020-12-18 | 国网江苏省电力有限公司常州供电分公司 | Concentrator accurate time synchronization method based on quadratic iteration algorithm |
CN114167944A (en) * | 2021-11-23 | 2022-03-11 | 北京华能新锐控制技术有限公司 | Power station daily generated energy calculation method and device and electronic equipment |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101399657A (en) * | 2007-09-26 | 2009-04-01 | Vega格里沙贝两合公司 | Method for the automatic time synchronisation of devices in network-based systems |
CN101695188A (en) * | 2009-10-15 | 2010-04-14 | 上海华为技术有限公司 | Method for correcting local time and clock server |
CN101783725A (en) * | 2009-01-20 | 2010-07-21 | 华为技术有限公司 | Method for outputting synchronous time, device and system thereof |
CN102231656A (en) * | 2011-06-20 | 2011-11-02 | 中兴通讯股份有限公司 | Method, system and device for keeping clock synchronization of NTP (Network Time Protocol) server |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6826123B1 (en) * | 2003-10-14 | 2004-11-30 | International Business Machines Corporation | Global recovery for time of day synchronization |
JP3863522B2 (en) * | 2003-12-25 | 2006-12-27 | Necエレクトロニクス株式会社 | Digital VCO, VCO circuit, PLL circuit, information recording apparatus, and synchronous clock signal generation method |
CN100350763C (en) * | 2004-01-02 | 2007-11-21 | 上海欣泰通信技术有限公司 | Time supply and synchronizing system for telecommunication network |
-
2011
- 2011-06-20 CN CN201110166074.9A patent/CN102231656B/en not_active Expired - Fee Related
-
2012
- 2012-03-13 WO PCT/CN2012/072259 patent/WO2012174892A1/en active Application Filing
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101399657A (en) * | 2007-09-26 | 2009-04-01 | Vega格里沙贝两合公司 | Method for the automatic time synchronisation of devices in network-based systems |
CN101783725A (en) * | 2009-01-20 | 2010-07-21 | 华为技术有限公司 | Method for outputting synchronous time, device and system thereof |
CN101695188A (en) * | 2009-10-15 | 2010-04-14 | 上海华为技术有限公司 | Method for correcting local time and clock server |
CN102231656A (en) * | 2011-06-20 | 2011-11-02 | 中兴通讯股份有限公司 | Method, system and device for keeping clock synchronization of NTP (Network Time Protocol) server |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2020155738A1 (en) * | 2019-01-28 | 2020-08-06 | Telefonaktiebolaget Lm Ericsson (Publ) | Clock distribution method and apparatus in network |
WO2020154840A1 (en) * | 2019-01-28 | 2020-08-06 | Telefonaktiebolaget Lm Ericsson (Publ) | Clock distribution method and apparatus in network |
US12041154B2 (en) | 2019-01-28 | 2024-07-16 | Telefonaktiebolaget Lm Ericsson (Publ) | Clock distribution method and apparatus in network |
Also Published As
Publication number | Publication date |
---|---|
CN102231656A (en) | 2011-11-02 |
CN102231656B (en) | 2016-09-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2012174892A1 (en) | Method, system and device for keeping clock synchronization of ntp servers | |
US8707382B2 (en) | Synchronizing presentations of multimedia programs | |
JP5433694B2 (en) | Improved method, system and apparatus for signal synchronization | |
US20140020013A1 (en) | System and method to provide out-of-band broadcast trigger synchronization and communication to insertion devices | |
EP1746760A1 (en) | Pon system having encryption function and encryption method of the pon system | |
WO2012097643A1 (en) | Method and apparatus for live media streams in iptv system | |
US20110310726A1 (en) | Method for processing channel switching failure case, terminal device, and channel switching server | |
US20080028093A1 (en) | Method and system for transitioning streamed digital video content between stream servers in a digital video network | |
WO2013029441A1 (en) | Mehtod and device for clock synchronization | |
WO2012163172A1 (en) | Clock synchronization method and device | |
WO2012058912A1 (en) | Method and node for time synchronization | |
WO2011134371A1 (en) | Method for synchronizing clocks and clock synchronization device | |
US20130318566A1 (en) | Subscriber line terminal, control method, and control method for pon system | |
US9706509B2 (en) | Synchronization of streaming data | |
US8126958B2 (en) | System and method for billing system interface failover resolution | |
KR20210102907A (en) | System and method for improving holdover performance in R-PHY network architecture | |
CN107547160B (en) | A kind of method for synchronizing time and device | |
WO2013083013A1 (en) | Synchronization method among network devices, network device and system | |
US8737434B2 (en) | PCR clock recovery in an IP network | |
WO2016119362A1 (en) | Clock synchronization method, router and cluster routing system | |
JP5578023B2 (en) | Station side device, home side device, optical communication system, and control method of optical communication system | |
JP5449229B2 (en) | Call relief system and call relief method | |
CN111510238A (en) | Method and system for centralized monitoring synchronization state of airborne clock | |
WO2014187421A1 (en) | Iptv channel switching method and apparatus and terminal | |
WO2008122178A1 (en) | A data transmission method, system and terminal |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 12801847 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 12801847 Country of ref document: EP Kind code of ref document: A1 |