CN107302452B - Control method for PBX service continuity - Google Patents
Control method for PBX service continuity Download PDFInfo
- Publication number
- CN107302452B CN107302452B CN201710453021.2A CN201710453021A CN107302452B CN 107302452 B CN107302452 B CN 107302452B CN 201710453021 A CN201710453021 A CN 201710453021A CN 107302452 B CN107302452 B CN 107302452B
- Authority
- CN
- China
- Prior art keywords
- pbx
- network
- deconcentrator
- connection
- network deconcentrator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
- H04L41/06—Management of faults, events, alarms or notifications
- H04L41/0654—Management of faults, events, alarms or notifications using network fault recovery
- H04L41/0663—Performing the actions predefined by failover planning, e.g. switching to standby network elements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/10—Active monitoring, e.g. heartbeat, ping or trace-route
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
- H04L43/0805—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters by checking availability
- H04L43/0817—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters by checking availability by checking functioning
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/50—Reducing energy consumption in communication networks in wire-line communication networks, e.g. low power modes or reduced link rate
Abstract
The invention relates to a control method for PBX business continuity, which comprises the following steps: step a: the first PBX, the second PBX and the network deconcentrator are respectively electrified, and the network deconcentrator is respectively in communication connection with the provider communication equipment, the first PBX and the second PBX; step b: the first PBX and the second PBX establish heartbeat connection to confirm whether the network deconcentrator works normally; step c: when the first PBX fails, FXS, FXO, E/T1 of the first PBX and the network port are switched to the second PBX through the network deconcentrator. By adopting the technical scheme of the invention, the switching of the PBX in fault can be realized through the handshake of USB to RS485 line, or the switching connection of the fault PBX can be realized through introducing a bidirectional certificate checking mechanism through a network deconcentrator with a network port. The method can switch FXS, FXO and E1/T1 hardware interfaces in time, and can ensure the continuity and high reliability of the PBX service by the standby PBX when the PBX fails.
Description
Technical Field
The invention belongs to the technical field of communication, and particularly relates to a hardware interface technology of cluster network equipment.
Background
With the development and maturity of social informatization, most industries are not separated from information services in normal operation, so that a highly reliable information service system is particularly important, and an HA (High availability cluster) is generated. Fig. 1 is a networking diagram of cluster network management in the prior art, and it can be known that HA is an effective solution for ensuring service continuity, and is based on a plurality of nodes, where the nodes are further divided into an active node and a standby node, the active node and the standby node are connected by using a jumper wire, the standby node is used for ensuring service continuity of the active node, when the active node cannot normally operate, HA cluster management software transfers service to the standby node after receiving an alarm message, and the standby node detects an alarm message of a failure of a main node and immediately starts to accept the service, thereby realizing continuous uninterrupted or short interruption of the service. The capability indexes of the active-standby nodes should be equal in theory, otherwise, the active-standby switching is slow, the service response is slow, and even the service is interrupted for a long time, which will not achieve the purpose of high reliability.
In view of the foregoing, the present invention will disclose a control method for PBX service continuity, which automatically switches FXO (Foreign Exchange Office, voice loop relay interface), FXS (Foreign Exchange Station, voice circuit interface) and E1/T1 hardware interface of the PBX in conjunction with corresponding cluster management devices.
Disclosure of Invention
The invention aims to provide a control method for the continuity of PBX business, which is matched with a network deconcentrator (HA) as disaster recovery use management of a main and standby hardware interface of a PBX.
In order to achieve the above object, a control method for PBX service continuity of the present invention mainly includes: step a: the first PBX, the second PBX and the network deconcentrator are respectively electrified, and the network deconcentrator is respectively in communication connection with the provider communication equipment, the first PBX and the second PBX; step b: the first PBX and the second PBX are connected through heartbeat to confirm whether the network deconcentrator works normally or not; step c: when the first PBX fails, FXS, FXO, E/T1 of the first PBX and the network port are switched to the second PBX through the network deconcentrator.
Preferably, the network splitter comprises at least one E1/T1, FXO, FXS external interfaces for connecting the first and second PBX interfaces, respectively.
Preferably, an analog relay knife switch is arranged in the network deconcentrator, and is communicated with the first PBX circuit by default when power is not supplied.
Preferably, the first PBX malfunction refers to one of the following two cases: the second PBX detects abnormal information received by the first PBX; the first PBX is directly dropped.
Preferably, the network deconcentrator is further provided with a pair of external network ports WAN and LAN, and two pairs of internal network ports WAN A and LAN A, WAN B and LAN B, wherein the internal network ports are respectively connected with the WAN and LAN of the two PBXs.
Preferably, the step c further includes: the second PBX sends a control instruction to the network deconcentrator through the USB-to-485 module; the network splitter switches the hardware FXS, FXO, E/T1 of the first PBX and the port to the second PBX.
Preferably, the step c includes, before: the first PBX transmits the broadcast packet group-transmitted IP information, the network deconcentrator analyzes the IP information in the broadcast packet and applies the IP information after receiving the broadcast packet, and then returns an acknowledgement message to the first PBX.
Preferably, the step c further includes: the network deconcentrator establishes SSL mutual authentication connection with the first PBX, after verification passes and connection is established, the network deconcentrator records the IP of the first PBX and keeps SSL long connection with the first PBX, and the SSL long connection comprises: heartbeat length connection based on ethernet; and receiving the long connection instructed by the first PBX.
Preferably, the step c includes: after the network deconcentrator receives the PBX switching instruction sent by the first PBX, the network deconcentrator switches FXO, FXS and E1/T1 to the second PBX, and then disconnects the previous connection and reestablishes connection with the second PBX.
Preferably, when the first PBX tries to send the heartbeat to the network deconcentrator three times, if the heartbeat is not replied, the network deconcentrator is considered to be faulty, a fault alarm is given, and the broadcast packet group sending IP information is restarted.
The technical scheme provided by the invention can switch FXS, FXO and E1/T1 hardware interfaces in time through the architecture setting of the network deconcentrator, so that when the main PBX fails, the standby PBX can take over the service in time, and the continuity and high reliability of the PBX service are ensured.
Furthermore, through the RS485 interface of the network deconcentrator, the USB-to-485 module is adopted for communication without adding the security of control instruction transmission by using a network, and compared with a network transmission mode, the development process is simplified and the development time is shortened.
Drawings
FIG. 1 is a networking diagram of a prior art clustered network management;
FIG. 2 is a diagram illustrating a network configuration using a network splitter according to a first embodiment of the present invention;
FIG. 3 is a schematic diagram of a relay circuit of a network splitter according to an embodiment of the present invention;
fig. 4 is a control flow diagram of a PBX service continuity method according to a first embodiment of the present invention;
fig. 5 is a control flow diagram of a PBX service continuity method in a second embodiment of the invention.
DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION
The basic principle of the invention is as follows: the through-cluster network splitter may also be referred to as a cluster management device (i.e., simply referred to herein as a "network splitter") that switches to the standby PBX when the primary PBX fails. The network deconcentrator comprises: 1E 1/T1, FXO, FXS, and the Internet access, and 2E 1/T1, FXO, FXS, and the Internet access are used for connecting interfaces of the master PBX and the standby PBX, respectively. The cluster wire divider is essentially an analog relay knife switch, defaults and is directly connected with a main PBX circuit when power is not supplied, when the main PBX is detected to be faulty through the Ethernet, a hardware circuit is switched to a standby PBX by using a relay, so that the main PBX hardware FXS, FXO, E/T1 and a network port which are faulty are timely switched to the standby PBX through the switch of the network wire divider, and meanwhile, the network wire divider is provided with LED indicator lamps for the network port, the main circuit and the standby circuit for the convenience of observing states.
In the following two embodiments, the configuration of the portal may be different: in the first embodiment, the network deconcentrator is provided with a pair of external network ports WAN and LAN, and two pairs of internal network ports WAN A and LAN A, WAN B and LAN B; in the second embodiment, the corresponding network deconcentrator has only one network port.
The invention is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present invention are shown in the drawings.
Fig. 2 is a network configuration diagram of an application network splitter according to a first embodiment of the present invention. As can be seen, the network splitter in the embodiments of the present invention switches the main PBX hardware FXS, FXO, E/T1 and the network ports to the standby PBX in time through the hardware circuit switch. The relay switch is connected with the hardware interface of the main PBX under the default condition, and the switch is connected to the interface of the standby PBX after the main PBX fails. Meanwhile, as can be seen from the figure, the RS485 mentioned in the text is the USB to 485 in the figure, and in addition, the USB Hub is a module which divides one USB port into two ports, mainly in order to prevent the USB port from being occupied in the use process of the RS485 module, thereby influencing the use of the USB port by other business of the PBX.
Fig. 3 is a schematic diagram of a relay circuit of a network splitter according to an embodiment of the present invention, to which reference is made for specific relay switch arrangements. The network splitter comprises 1E 1/T1, FXO, FXS external interfaces, and 2 interfaces of E1/T1, FXO, FXS for connecting the main PBX and the standby PBX respectively. The network port refers to a WAN port and a LAN port, the other RS485 interface is not a switch, and is directly connected, and the main PBX and the standby PBX are directly connected to the network deconcentrator.
The above-described network splitter provides an efficient solution for a PBX to ensure service continuity by switching the malfunctioning master PBX hardware FXS, FXO and E1/T1 interfaces to the standby PBX in time through the hardware circuit switch. The relay switch is connected with the hardware interface of the main PBX under the default condition, and the switch is connected to the interface of the standby PBX after the main PBX fails.
Specific embodiment-control scheme based on RS485 line.
The network deconcentrator adopted in the specific embodiment has an RS485 interface without a network port, so that the transmission noise of an RS485 line and the handshake from the USB to the RS485 line are required to be considered, and the network deconcentrator has transmission distance limitation, but has good safety. At this time, the communication between the network deconcentrator and the master/slave PBX is performed by the USB-to-485 module.
In this case, the interfaces of the network splitter are basically described below, and the network splitter is particularly provided with an RS485 interface. At this time, the interfaces on the network splitter are described as follows:
fig. 4 is a control flow diagram of a PBX service continuity method according to a first embodiment of the present invention. With reference to the figure, the PBX service continuity method according to the first embodiment of the present invention mainly includes the following steps:
step 110: the network deconcentrator employs a single adapter power supply. The main PBX, the standby PBX and the network deconcentrator are respectively electrified, FXO, FXS, E/T1 of a provider and a network cable are connected to an interface corresponding to the outside line of the network deconcentrator, then FXO, FXS, E/T1 and interfaces such as a network port are respectively connected to the main PBX and the standby PBX, the network cable is connected between the main PBX and the network deconcentrator, the standby PBX and the network deconcentrator, and the heartbeat line is connected between the main PBX and the standby PBX.
Step 120: after the master PBX and the standby PBX are judged, the role of the master PBX is confirmed, and a switching instruction is sent to the network deconcentrator through the USB-to-485 module. The network deconcentrator receives the control instruction, dials the line switch to the main PBX, and completes the switching of the line.
Step 130: when the main PBX equipment fails, the standby PBX detects that abnormal information of the main PBX equipment is received, or the main PBX equipment is directly disconnected, and the standby PBX sends a control instruction to the network deconcentrator through the USB converting 485 module. And switching FXO, FXS, E/T1 and network ports and other interface lines, thereby achieving the switching of the main PBX and the standby PBX and ensuring the normal operation of the whole system.
The second embodiment is a control scheme based on network ports.
In the specific embodiment, the network deconcentrator box is provided with a network port without an RS485 interface, network transmission safety needs to be considered, network attack is avoided, and mechanisms such as bidirectional certificate verification and the like are introduced. At this time, the interfaces on the network splitter are described as follows:
meanwhile, in order to ensure the self-configurability, the second network deconcentrator of the embodiment is further provided with a control port, a reset key and a network port, wherein the network port is used for receiving a switching instruction and detecting power failure, and in order to facilitate the observation of the state, the network port, the main circuit and the standby circuit are further provided with LED indicator lamps. Network communication between the network deconcentrator and the main PBX and the standby PBX is provided by an opensl library for ssl bidirectional authentication encryption so as to ensure the reliability of communication.
Fig. 5 is a control flow diagram of a PBX service continuity method in a second embodiment of the invention. As can be seen from the figure, in the second embodiment of the present invention, the PBX service continuity method mainly includes the following steps:
step 210: the network deconcentrator employs a single adapter power supply. The main PBX, the standby PBX and the network deconcentrator are respectively electrified, FXO, FXS, E/T1 of a provider and a network cable are connected to an interface corresponding to the outside line of the network deconcentrator, then FXO, FXS, E/T1 and interfaces such as a network port are respectively connected to the main PBX and the standby PBX, the network cable is connected between the main PBX and the network deconcentrator, the standby PBX and the network deconcentrator, and the heartbeat line is connected between the main PBX and the standby PBX.
Step 220: the main PBX transmits the broadcast packet group-transmitted IP information, the network deconcentrator analyzes the IP information in the broadcast packet and applies the IP information after receiving the broadcast packet, and then returns a confirmation message to the main PBX, and at the moment, the main PBX stops transmitting the broadcast packet.
Step 230: the network deconcentrator starts to establish SSL bidirectional authentication connection with the main PBX, after verification passes and connection is established, the network deconcentrator records the IP of the main PBX, and keeps two SSL long connections with the main PBX, one is a heartbeat long connection based on Ethernet to confirm whether the network deconcentrator works normally, and the other is a long connection for receiving instructions sent by the main PBX.
Step 240: the network deconcentrator starts to receive the instruction sent by the main PBX and processes the returned result, and the instruction comprises: a main-standby switching instruction, a reset instruction and an upgrade firmware instruction. After the network splitter receives the primary and backup switch commands from the primary PBX, the network splitter splits FXO, FXS and E1/T1 to the new primary PBX and disconnects the previous connection to reestablish connection with the backup PBX, i.e., the new primary PBX. The network deconcentrator receives the reset instruction and executes factory restoration operation; and receiving an instruction for upgrading the firmware, and executing the operation of upgrading the firmware.
Step 250: when the main PBX tries to send heartbeat to the network deconcentrator three times, if the main PBX does not get replied, the network deconcentrator is considered to have faults, the fault alarm of the network deconcentrator is thrown out of the page, and the broadcast packet group sending IP information is restarted.
Note that the above is only a preferred embodiment of the present invention and the technical principle applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described, but is capable of numerous modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, while the invention has been described in connection with the above embodiments, the invention is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the invention, which is set forth in the following claims.
Claims (1)
1. A control method for PBX service continuity, the method comprising:
step a: the first PBX, the second PBX and the network deconcentrator are respectively electrified to respectively connect the network deconcentrator with the provider communication equipment, the first PBX and the second PBX in a communication way;
step b: the first PBX is connected with the second PBX through heartbeat;
step c: when the first PBX fails, FXS, FXO, E/T1 of the first PBX and a network port are switched to the second PBX through the network deconcentrator;
the step a comprises the following steps: the network deconcentrator comprises an E1/T1, FXO, FXS and an external line interface of a network port for connecting the provider communication equipment, and the two E1/T1, FXO, FXS and the network port are respectively connected with the first PBX interface and the second PBX interface; an analog relay knife switch is arranged in the network deconcentrator, and is communicated with the first PBX circuit by default when no power is supplied;
the step c is preceded by: the first PBX transmits the broadcast packet group-transmitting IP information, the network deconcentrator analyzes the IP information in the broadcast packet and applies the IP information after receiving the broadcast packet, and then returns a confirmation message to the first PBX;
the network deconcentrator establishes SSL bidirectional authentication connection with the first PBX, and after verification passes and connection is established, the network deconcentrator records the IP of the first PBX and keeps SSL long connection with the first PBX;
the SSL long connection includes: heartbeat length connection based on ethernet; receiving long connection of a PBX switching instruction sent by the first PBX;
the step c comprises the following steps: after the network deconcentrator receives the PBX switching instruction sent by the first PBX, the network deconcentrator can switch FXO, FXS and E1/T1 to the second PBX and then disconnect the previous connection and reestablish connection with the second PBX;
the step c further includes: the method for confirming whether the network deconcentrator works normally by using the Ethernet-based heartbeat connection specifically comprises the following steps: when the first PBX tries to send the heartbeat to the network deconcentrator three times, if the network deconcentrator is not replied, the network deconcentrator is considered to have faults, fault alarming is given, and the broadcast packet group sending IP information is restarted to be sent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710453021.2A CN107302452B (en) | 2017-06-15 | 2017-06-15 | Control method for PBX service continuity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710453021.2A CN107302452B (en) | 2017-06-15 | 2017-06-15 | Control method for PBX service continuity |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107302452A CN107302452A (en) | 2017-10-27 |
| CN107302452B true CN107302452B (en) | 2023-08-15 |
Family
ID=60134744
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710453021.2A Active CN107302452B (en) | 2017-06-15 | 2017-06-15 | Control method for PBX service continuity |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107302452B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11622046B2 (en) * | 2021-03-29 | 2023-04-04 | Intermedia.Net, Inc. | System for cloud-enabling a premise PBX |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998014844A1 (en) * | 1996-10-04 | 1998-04-09 | The Timken Company | Telecommunications disaster recovery system |
| CN101141507A (en) * | 2007-10-08 | 2008-03-12 | 杭州华三通信技术有限公司 | Power-off escape method and apparatus |
| CN101656798A (en) * | 2008-08-19 | 2010-02-24 | 阿瓦亚公司 | Rerouting of trunks by a PBX to an alternate PBX |
| CN101917210A (en) * | 2010-07-16 | 2010-12-15 | 天津七一二通信广播有限公司 | Railway wireless train dispatching station radio |
| CN106506219A (en) * | 2016-11-16 | 2017-03-15 | 汉柏科技有限公司 | A kind of for data transfer in data filtering failure changing method and system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8111614B2 (en) * | 2006-11-29 | 2012-02-07 | Net2Phone, Inc. | Remote redundant voice server system |
-
2017
- 2017-06-15 CN CN201710453021.2A patent/CN107302452B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1998014844A1 (en) * | 1996-10-04 | 1998-04-09 | The Timken Company | Telecommunications disaster recovery system |
| CN101141507A (en) * | 2007-10-08 | 2008-03-12 | 杭州华三通信技术有限公司 | Power-off escape method and apparatus |
| CN101656798A (en) * | 2008-08-19 | 2010-02-24 | 阿瓦亚公司 | Rerouting of trunks by a PBX to an alternate PBX |
| CN101917210A (en) * | 2010-07-16 | 2010-12-15 | 天津七一二通信广播有限公司 | Railway wireless train dispatching station radio |
| CN106506219A (en) * | 2016-11-16 | 2017-03-15 | 汉柏科技有限公司 | A kind of for data transfer in data filtering failure changing method and system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107302452A (en) | 2017-10-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1982447B1 (en) | System and method for detecting and recovering from virtual switch link failures | |
| EP2798782B1 (en) | Technique for handling a status change in an interconnect node | |
| CN104486128B (en) | A kind of system and method for realizing redundancy heartbeat between dual controller node | |
| CA2941538A1 (en) | Link switching method, device, and system | |
| CN110838962B (en) | Marine network system and marine system | |
| CN103684845A (en) | Network backup device and network system with same | |
| CN107302452B (en) | Control method for PBX service continuity | |
| JP6383232B2 (en) | Relay system and switch device | |
| EP2074758B1 (en) | Method for protection switching in ring topologies | |
| JP4967674B2 (en) | Media service system, media service device, and LAN redundancy method used therefor | |
| CN102638369B (en) | Method, device and system for arbitrating main/standby switch | |
| JP5523861B2 (en) | Packet relay apparatus and fault diagnosis method thereof | |
| US9571298B2 (en) | Network system | |
| CN109510725B (en) | Communication equipment fault detection system and method | |
| US7675850B2 (en) | Apparatus for realizing soft-switch allopatric disaster recovery based on packet network | |
| KR101234102B1 (en) | A circuit automatic switching apparatus and its operational method thereof | |
| JP6204397B2 (en) | COMMUNICATION DEVICE, COMMUNICATION SYSTEM, COMMUNICATION METHOD, AND PROGRAM | |
| JP2016040885A (en) | Relay system and relay device | |
| KR20150059697A (en) | Method and System for detecting network failure in Software Defined Network | |
| KR20060105045A (en) | Method for backup switching spatially separated switching systems | |
| KR20090099698A (en) | Wireless bridge communication apparatus that do duplexing in distribution automation system | |
| KR102200433B1 (en) | Virtual private network devices and method for traffic switching using the same | |
| JP2012129864A (en) | Communication system and method for controlling user access device | |
| KR102188479B1 (en) | Apparatus for duplexing data | |
| KR102197916B1 (en) | Apparatus for duplexing data |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |