CN111106963B

CN111106963B - Method for realizing circuit simulation service and distributed system

Info

Publication number: CN111106963B
Application number: CN201911354289.6A
Authority: CN
Inventors: 焦勇; 宁成月; 张鹏
Original assignee: Raisecom Technology Co Ltd
Current assignee: Raisecom Technology Co Ltd
Priority date: 2019-12-25
Filing date: 2019-12-25
Publication date: 2022-10-28
Anticipated expiration: 2039-12-25
Also published as: CN111106963A

Abstract

Disclosed herein are a method for implementing circuit simulation service and a distributed system, the distributed system comprising: one or more CES single disks and a master disk; the master control disk is connected with each CES single disk; one or more TDM interfaces are arranged on the CES single disk, and a PSN network interface is arranged on the master control disk; a CES single disc for obtaining configuration parameters through a control channel; the TDM signals are encapsulated into CES service messages and then are sent to the master control panel through a data channel; extracting TDM information from a received CES message and converting the TDM information into a TDM signal; the main control disk is used for forwarding the CES message of the local CES single disk; and sending the received CES message of the remote CES equipment to the CES single disk through a data channel. The technical scheme can realize flexible expansion of circuit simulation service capacity, meet the capacity requirements of different users and save hardware cost.

Description

Method for realizing circuit simulation service and distributed system

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method and a distributed system for implementing a circuit simulation service.

Background

With the evolution of network technology and network convergence, PSN (Packet Switch Networks) which uses data packets as basic units for network data transmission and exchange has occupied a dominant position.

However, existing PDH (Plesiochronous Digital Hierarchy)/SDH (Synchronous Digital Hierarchy) networks will exist for a long Time, and user TDM (Time Division Multiplex) devices existing in large numbers on the networks will continue to be used. In order to protect the investment of users on TDM equipment, it is necessary to provide TDM service access and TDM data transparent transmission capability in the next generation of packet switching networks.

CES (Circuit Emulation Service) is a technology for carrying a conventional TDM Service over a PSN. The basic principle of CES is to encapsulate a TDM service signal into a CES message on a PE (Provider Edge) device at a PSN inlet and transmit the CES message on the PSN, decapsulate the CES message on a PE device at a PSN outlet, regenerate a TDM service signal, and complete transparent transmission.

In the related technology, no matter whether the user needs the CES function, the CES chip is integrated on the device motherboard, so that on one hand, the cost of the device is increased, and on the other hand, because the CES chip is integrated on the device motherboard, once the CES service needs to be upgraded or expanded, other services running on the network are necessarily affected, which is not favorable for flexible deployment of CES service and difference requirements of different customers.

Disclosure of Invention

The invention provides a method and a distributed system for realizing circuit simulation services, which can realize flexible expansion of circuit simulation service capacity, meet the capacity requirements of different users and save hardware cost.

According to a first aspect of the present application, an embodiment of the present invention provides a distributed system for implementing a circuit emulation service, including:

one or more Circuit Emulation Services (CES) single disks and a master control disk; the master control disk is connected with each CES single disk; one or more time division multiplexing TDM interfaces are arranged on the CES single disk, and a Packet Switched Network (PSN) network interface is arranged on the master control disk;

the CES single disk is used for obtaining configuration parameters required by CES service through a control channel between the CES single disk and a master control disk; encapsulating the TDM signals extracted from the TDM interface of the CES single disk into a CES service message, and then transmitting the CES service message to a master control disk through a data channel between the CES single disk and the master control disk; receiving a CES message from a data channel of the CES single disk, extracting TDM information from the CES message, converting the TDM information into a TDM signal, and forwarding the TDM signal through a TDM interface of the CES single disk; wherein the configuration parameters include at least: PSN network parameters;

the main control disk is used for forwarding a CES message sent by the CES single disk through a PSN network interface of the main control disk; and after receiving a CES message from a PSN network interface of the master control disk, sending the CES message to the CES single disk through a data channel between the CES single disk and the master control disk according to the CES single disk corresponding to the CES message.

According to a second aspect of the present application, an embodiment of the present invention provides a method for implementing a circuit emulation service, including:

a circuit emulation service CES single disk or any one of a plurality of CES single disks obtains configuration parameters required by the CES service through a control channel between the CES single disk and a master control disk; one or more time division multiplexing TDM interfaces are arranged on the CES single disk, and a PSN network interface is arranged on the master control disk; the configuration parameters at least comprise: PSN network parameters;

any one CES single disk encapsulates TDM signals extracted from a TDM interface of the CES single disk into CES service messages, then the CES service messages are sent to a master control disk through a data channel between the CES single disk and the master control disk, and the master control disk forwards the CES messages through a PSN network interface of the master control disk;

after receiving a CES message from a PSN network interface of a master control disk, a master control disk sends the CES message to the CES single disk through a data channel between the CES single disk and the master control disk according to the CES message, the CES single disk extracts TDM information from the CES message and converts the TDM information into TDM signals, and the TDM signals are forwarded through a TDM interface of the CES single disk.

Compared with the related technology, the method for realizing the circuit simulation service and the distributed system provided by the embodiment of the invention can support the CES function of the equipment through the distributed CES single disk, and the user only needs the CES single disk when building a network supporting the CES function. Meanwhile, due to the distributed system, the functions related to the CES service are realized by the CES single disk, and the control of a master control disk is not needed, so that the coupling of the CES service and other services on software and hardware of equipment is greatly reduced. Through the design of the distributed pluggable CES single disk, the upgrading of CES service and the network capacity expansion are more convenient and flexible.

Drawings

Fig. 1 is a schematic diagram of a distributed system for implementing a circuit simulation service according to embodiment 1 of the present invention;

fig. 2 is a schematic view of a connection between a CES single disk and a master disk according to embodiment 1 of the present invention;

fig. 3 is a schematic view of a typical application scenario of the distributed CES system in embodiment 1 of the present invention;

fig. 4 is a flowchart of a method for implementing circuit simulation services according to embodiment 2 of the present invention.

Detailed Description

To make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

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

The CES service is a service that encapsulates TDM signals into data packets in PSN format, and the data packets are in IP format. The following embodiments illustrate the implementation of the CES service data forwarding plane and the control plane in a distributed architecture and the operation and maintenance of a device using a distributed CES system in a typical application scenario. The "network" appearing hereinafter refers to a "PSN network".

Example 1

As shown in fig. 1, an embodiment of the present invention provides a distributed system for implementing a circuit simulation service, including: one or more Circuit Emulation Services (CES) single disks 10 and a master control disk 20; the master control disk 20 is connected with each CES single disk 10; one or more time division multiplexing TDM interfaces 101 are arranged on the CES single disk 10, and a packet switched network PSN network interface 201 is arranged on the master control disk 20;

a CES single disk 10, configured to obtain configuration parameters required by a CES service through a control channel between the CES single disk and a master control disk; the configuration parameters at least include: PSN network parameters; encapsulating the TDM signals extracted from the TDM interface of the CES single disk into a CES service message, and then transmitting the CES service message to a master control disk through a data channel between the CES single disk and the master control disk; receiving a CES message from a data channel of the CES single disk, extracting TDM information from the CES message, converting the TDM information into a TDM signal, and forwarding the TDM signal through a TDM interface of the CES single disk;

the main control disk 20 is configured to forward a CES message sent by a CES single disk through a PSN network interface of the main control disk; after receiving a CES message from a PSN network interface of the master control disk, sending the CES message to the CES single disk through a data channel between the CES single disk and the master control disk according to the CES single disk corresponding to the CES message;

as shown in fig. 2, any CES single disc 10 includes: a TDM interface 101, a control module 102 and a CES service chip 103; the master control panel 20 includes: PSN network interface 201, control module 202 and switch chip 203; the switch chip 203 is provided with a first port 2031, a second port 2032 and a third port 2033; a first interface 1031 and a second interface 1032 are arranged on the CES service chip 103;

a first interface of a CES service chip of any CES single disk is connected with a TDM interface of the CES single disk, and a second interface of the CES service chip is connected with a second port of the exchange chip; the control module of the CES single disk is connected with the first port of the exchange chip;

a control channel of any CES single disk is established between a control module of the CES single disk and a first port of the switch chip; the data channel of the CES single disk is established between the CES service chip of the CES single disk and the second port of the switching chip;

wherein the PSN network interface comprises: GE (Gigabit Ethernet) interface;

the control channel is used for transmitting signaling and control information, and the data channel is used for transmitting CES service data.

In one embodiment, the MAC (Media Access Control) address and the IP address of any CES single disc are set before factory shipment; the TDM parameter of any CES single disk, the destination IP address of remote CES equipment and the IP address of next-hop equipment are preset;

wherein the TDM parameters comprise: time slot and payload length; the time slot refers to a time slot corresponding to a TDM signal to be extracted by the CES service, such as one time slot or a combination of multiple time slots in 1 to 31 time slots of the E1 interface. The payload length refers to how many bytes of data the CES service is to extract from the TDM service are encapsulated in the IP message.

Each CES disc has a fixed MAC (Media Access Control) address and an IP address.

In one embodiment, the CES single disk 10 is configured to obtain configuration parameters required for CES service through a control channel between the CES single disk and a master disk in the following manner: the control module of the CES single disk sends an ARP request message to a first port of a switching chip of a master control disk; after receiving an APR response message of next-hop equipment through a control channel between the CES single disk and the master control disk, the control module of the CES single disk obtains an MAC address of the next-hop equipment from the APR response message, and issues TDM parameter information and network parameter information required by CES service to a CES service chip of the CES single disk; wherein the network parameter information includes: a destination IP address of the remote CES device, an IP address of the next-hop device, and a MAC address of the next-hop device.

The main control disk 20 is configured to forward a CES message sent by a CES single disk through a PSN network interface of the main control disk in the following manner: the exchange chip of the master control disk sends the ARP request message to a third port of the exchange chip through two-layer exchange; wherein, the MAC address learning function of the first port of the exchange chip is closed; the switching chip of the master control disk receives an ARP response message replied by next hop equipment from the third port, learns the MAC address of the next hop equipment from the ARP response message, stores the learned MAC address in an MAC address table, and redirects the ARP response message to the first port of the switching chip by matching an ARP protocol number and a target IP address through an Access Control List (ACL);

wherein the reason for closing the MAC address learning function of the first port is: after a subsequent CES data packet enters the master control disk through the third port of the switch chip, it is desirable that the CES data packet can be sent to the CES single disk through the two-layer switch data channel, that is, it is desirable that the CES data packet can be forwarded to the second port of the switch chip, and it is undesirable that the CES data packet is forwarded to the control channel (the first port of the switch chip) through the two-layer switch. Therefore, if the MAC address learning function of the first port of the switch chip is turned on, the first port learns the MAC address of the CES single disk when receiving the ARP request of the CES single disk, and when the switch chip subsequently receives a CES service packet, the MAC address is forwarded to the first port of the switch chip through two-layer switching, which causes a CES data flow direction error (flowing to a control channel).

The reason why the switching chip redirects the ARP reply message using the ACL is that if the two-layer forwarding is used, the ARP reply message is forwarded and sent to the second port of the switching chip through the two-layer forwarding, and the second port belongs to a data channel, and it is not desirable that the ARP reply message is sent to the CES single disk by going through the data channel, but it is desirable that the ARP reply message is sent to the CES single disk through the control channel, so that the ARP reply message needs to be redirected to the first port of the switching chip in an ACL manner. That is, through ACL redirection, the ARP reply message and the CES service message can be distinguished, so that the ARP reply message is sent to the CES single disk through the control channel, and the CES service message is sent to the CES single disk through the data channel.

In an embodiment, the master control disk is further configured to configure, when a CES single disk is initialized, a MAC address of the CES single disk as a static MAC address to a second port of a switch chip of the master control disk;

by statically configuring the MAC address of the local CES single disk at the second port of the switching chip, the CES service message sent by the next hop device can be directly forwarded to the second port according to the MAC address without flooding to other ports after entering the third port of the switching chip of the master control disk.

In an embodiment, the CES single disk is configured to receive a TDM signal from any TDM interface through a CES service chip of the CES single disk, encapsulate the TDM signal into an IP format packet, and then send the IP format packet to a second port of an exchange chip of a master control disk through a data channel from a second interface of the CES service chip;

the main control panel is used for looking up an MAC address table through an exchange chip of the main control panel, sending the IP message to a network interface of the main control panel through a third port of the exchange chip and outputting the IP message to a PSN network from the network interface. The switching chip learns the MAC address of the next-hop equipment on the third port in the ARP interaction process;

in an implementation manner, the master is configured to receive, through a third port of a switch chip of the master, a CES service packet sent by a next hop device from a network interface of the master, directly forward the CES service packet to a second port of the switch chip according to a destination MAC address, and send the CES service packet to a CES interface of a service chip of a CES single disk through a data channel between the second port of the switch chip and the CES single disk; the MAC address of the CES single disk is used as a static MAC and is configured to a second port of a switching chip of a master control disk in advance;

the CES single disk is used for extracting TDM payload information from a CES service message received from the second interface through a CES service chip of the CES single disk, converting the TDM payload information into a TDM signal, and transmitting the TDM signal from the first interface of the CES service chip to the TDM interface of the CES single disk;

as shown in fig. 3, in some application scenarios, the aggregation end device is connected to a plurality of CPE (Customer Provider Edge) devices through the PSN network. For example, a bank headquarters in a city sets aggregation equipment, and a plurality of branches sets CPE equipment. After the sink device integrates the CES function, the sink device is connected to a next hop device (router) through the GE interface, and if the next hop device is replaced, that is, the MAC address of the next hop device changes, in this case, an operation and maintenance person is required to manually delete the CES service on the sink device and then reconstruct the CES service, which increases the operation and maintenance complexity of the sink device. In addition, if the CPE device fails or the PSN network fails, the aggregation end device still transmits a CES data packet to the PSN network due to lack of fault diagnosis, and thus occupies network bandwidth resources.

For the above typical application scenario, the embodiment of the present invention deploys a distributed CES system on a convergence end device, that is, the convergence end device of the embodiment of the present invention is a distributed CES device, and includes: a master control disk and one or more pluggable CES singles disks. The embodiment of the invention optimizes the operation and the maintenance of the distributed CES equipment: 1) If the next-hop device is replaced, after the MAC address of the next-hop device stored on the CES single disk is aged, the CES single disk can obtain the new MAC address of the next-hop device again through an ARP request, after the control module of the CES single disk obtains the new MAC address of the next-hop device, the configuration register of the CES service chip is directly modified, the new MAC address is updated into the CES service chip, and the CES data packets sent afterwards all use the new MAC address as the target MAC address. 2) The control module of the CES single disk confirms whether the network or the remote CPE device is faulty or not by periodically (e.g., 30 seconds) ping (Internet Groper) the remote CPE device. When the PSN network or the far-end CPE is in failure, the ping request is overtime, and after the ping request is continuously overtime for a preset number of times, the control module of the CES single disk can control the CES service chip to stop the transmission of the CES service in the uplink direction, and the message is not sent to the PSN network any more. And after the fault is recovered, the control module of the CES single disk controls the CES service chip, starts the CES service transmission in the uplink direction and sends a message to the PSN network. Therefore, the automatic stop of the CES data flow after the PSN network fault and the automatic recovery of the CES data flow after the network recovery can be realized.

In an implementation manner, the CES single disk is further configured to, after an MAC address of a next-hop device stored on the CES single disk is aged, a control module of the CES single disk obtains a new MAC address of the next-hop device again through an ARP request, and updates a network parameter of a CES service chip of the CES single disk according to the new MAC address;

in an implementation manner, the CES single disk is further configured to periodically ping a remote CES device through a control channel of the CES single disk by the control module of the CES single disk, after a ping request continuously times out for a preset number of times, the control module of the CES single disk determines that a fault occurs, controls the CES service chip of the CES single disk to stop sending a CES message to the PSN network, and after the fault is recovered, the control module of the CES single disk controls the CES service chip of the CES single disk to recover to send the CES message to the PSN network.

The distributed CES system realizes flexible expansion of the CES service capacity of the whole machine through the distributed CES single-disk design, meets the capacity requirements of different users, and saves the hardware cost. In the aspect of equipment usability, the software is used for detecting network changes and synchronously updating the CES service chip, so that the sensing of different network conditions and the automatic adjustment of services are realized. Compared with the traditional operation and maintenance means, the optimization and improvement scheme of the usability improves the operation and maintenance efficiency, saves the occupation of network resources and has good practical value.

Example 2

As shown in fig. 4, an embodiment of the present invention provides a method for implementing a circuit emulation service, including:

step S110, obtaining configuration parameters needed by CES service through a control channel between a CES single disk and a master control disk by a circuit emulation service CES single disk or any one of a plurality of CES single disks; the CES single disk is provided with one or more time division multiplexing TDM interfaces, and the master control disk is provided with a PSN network interface; the configuration parameters at least comprise: PSN network parameters;

step S120, any one CES single disk encapsulates TDM signals extracted from the TDM interface of the CES single disk into CES service messages, then the CES service messages are sent to the master control disk through a data channel between the CES single disk and the master control disk, and the CES messages are forwarded by the master control disk through a PSN network interface of the master control disk;

step S130, after receiving a CES message from a PSN network interface of a master control disk, the master control disk sends the CES message to the CES single disk through a data channel between the CES single disk and the master control disk according to the CES message, the CES single disk extracts TDM information from the CES message and converts the TDM information into a TDM signal, and the TDM signal is forwarded through a TDM interface of the CES single disk;

in one embodiment, any one CES single disc includes: the system comprises a TDM interface, a control module and a CES service chip; the master control panel includes: PSN network interface, control module and exchange chip; a first port, a second port and a third port are arranged on the exchange chip; a first interface and a second interface are arranged on the CES service chip;

a first interface of a CES service chip of any one CES single disk is connected with the TDM interface of the CES single disk, and a second interface of the CES service chip is connected with a second port of the exchange chip; the control module of the CES single disk is connected with the first port of the exchange chip;

wherein the PSN network interface comprises: GE (Gigabit Ethernet) interface;

in one embodiment, the MAC (Media Access Control) address and the IP address of any CES single disc are set before factory shipment; the TDM parameter of any CES single disk, the destination IP address of remote CES equipment and the IP address of next hop equipment are preset;

wherein the TDM parameters comprise: time slot and payload length;

in one embodiment, the obtaining, by the one circuit emulation service CES single disk or any one of multiple CES single disks, configuration parameters required for CES service through a control channel between the CES single disk and a master disk includes:

for any CES single disk, the control module of the CES single disk sends an ARP (Address Resolution Protocol) request message to a first port of a switching chip of a main control disk, and the switching chip of the main control disk sends the ARP request message to a third port of the switching chip through two-layer switching; wherein, the MAC address learning function of the first port of the exchange chip is closed;

the switching chip of the master Control disk receives an ARP response message replied by next-hop equipment from a third port, learns the MAC address of the next-hop equipment from the ARP response message, stores the learned MAC address in an MAC address table, matches an ARP protocol number and a target IP address through an ACL (Access Control List), and redirects the ARP response message to the first port of the switching chip;

after receiving the APR response message through a control channel between the CES single disk and the master control disk, the control module of the CES single disk obtains an MAC address of next-hop equipment from the APR response message, and issues TDM parameter information and network parameter information required by the CES service to a CES service chip of the CES single disk; wherein the network parameter information includes: a destination IP address of the remote CES device, an IP address of the next hop device, and a MAC address of the next hop device.

In one embodiment, the method further comprises:

when the main control disk initializes the CES single disk, configuring the MAC address of the CES single disk as a static MAC address to a second port of a switching chip of the main control disk;

After receiving the ARP response message sent by the switching chip of the master control disk, the control module of the CES single disk obtains the MAC address of the next hop, so that the control module of the CES single disk can obtain all the information of the network parameters required by the CES service. And after the control module of the CES single disk completely obtains the TDM parameter information and the network parameter information of the CES service, all the parameter information (the TDM parameter information and the network parameter information) required by the CES service is transmitted to a CES service chip.

And after the CES service chip of the single disk obtains all the parameter information required for opening the CES service, the transmission of the CES data stream is started. The forwarding process of uplink and downlink CES data messages is as follows:

in an uplink direction (from TDM to PSN), a CES service chip of the CES single disk receives a TDM signal from any TDM interface, encapsulates the TDM signal into an IP format message, and then sends the IP format message from a second interface of the CES service chip to a second port of the switching chip of the master control disk through a data channel. And the exchange chip checks an MAC address table, sends the IP message to a network interface of a main control panel through a third port of the exchange chip and outputs the IP message to a PSN network from the network interface. And the switching chip learns the MAC address of the next-hop equipment on the third port in the ARP interaction flow.

In a downlink direction (from the PSN to the TDM), a third port of a switching chip of the master control disk receives, from a network interface of the master control disk, a CES service packet sent by a next hop device, directly forwards the CES service packet to a second port of the switching chip according to a destination MAC address, and sends the CES service packet to a second interface of the service chip of the CES single disk through a data channel between the second port of the switching chip and the CES single disk. And the MAC address of the CES single disk is configured as a static MAC to a second port of the switching chip of the master control disk in advance. The MAC address of the CES single disk is statically configured at the second port of the switch chip, so that when the switch chip receives the MAC address of the local-end CES single disk from the third port, the MAC address is directly forwarded to the second port of the switch chip according to the destination MAC address, and the MAC address is not flooded to other ports. And after receiving the CES service message from the second interface, the CES service chip of the CES single disk extracts TDM payload information from the CES service message and converts the TDM payload information into a TDM signal, and the TDM signal is sent to the TDM interface of the CES single disk from the first interface of the CES service chip.

In one embodiment, the method further comprises:

after the MAC address of the next-hop equipment stored on the CES single disk is aged, the control module of the CES single disk obtains the new MAC address of the next-hop equipment again through an ARP request, and the network parameters of the CES service chip are updated according to the new MAC address; after obtaining a new MAC address of a next hop device, the control module of the CES single disk directly modifies a configuration register of the CES service chip, updates the new MAC address into the CES service chip, and uses the new MAC address as a target MAC address for CES service data packets sent afterwards;

in one embodiment, the method further comprises:

the control module of the CES single disk regularly pings the remote CES equipment through the control channel of the CES single disk, when the ping request continuously overtimes and reaches the preset times, the control module of the CES single disk judges that a fault occurs, controls the CES service chip to stop sending CES messages to the PSN network, and when the fault is recovered, the control module of the CES single disk controls the CES service chip to recover to send CES messages to the PSN network.

It will be understood by those of ordinary skill in the art that all or some of the steps of the methods, systems, functional modules/units in the devices disclosed above may be implemented as software, firmware, hardware, or suitable combinations thereof. In a hardware implementation, the division between functional modules/units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component may have multiple functions, or one function or step may be performed by several physical components in cooperation. Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on computer readable media, which may include computer storage media (or non-transitory media) and communication media (or transitory media). The term computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data, as is well known to those of ordinary skill in the art. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital Versatile Disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by a computer. In addition, communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media as is well known to those skilled in the art.

It is to be noted that the present invention may be embodied in other specific forms, and that various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A distributed system for implementing circuit emulation services, comprising: one or more Circuit Emulation Services (CES) single disks and a master control disk; the master control disk is connected with each CES single disk; one or more time division multiplexing TDM interfaces are arranged on the CES single disk, and a Packet Switched Network (PSN) network interface is arranged on the master control disk;

the main control disk is used for forwarding a CES message sent by the CES single disk through a PSN network interface of the main control disk; and after receiving a CES message from the PSN network interface of the main control disk, sending the CES message to the CES single disk through a data channel between the CES single disk and the main control disk according to the CES single disk corresponding to the CES message.

2. The distributed system of claim 1, wherein:

any CES single disc includes: the system comprises a TDM interface, a control module and a CES service chip; the master control panel includes: PSN network interface, control module and exchange chip; a first port, a second port and a third port are arranged on the exchange chip; a first interface and a second interface are arranged on the CES service chip;

a first interface of a CES service chip of any CES single disk is connected with a TDM interface of the CES single disk, and a second interface of the CES service chip is connected with a second port of the exchange chip; the control module of the CES single disk is connected with the first port of the switching chip;

a control channel of any CES single disk is established between a control module of the CES single disk and a first port of the switch chip; and the data channel of the CES single disk is established between the CES service chip of the CES single disk and the second port of the exchange chip.

3. The distributed system of claim 2, wherein:

the CES single disk is used for sending an ARP request message to a first port of a switching chip of a master control disk through a control module of the CES single disk; the control module of the CES single disk obtains the MAC address of the next hop equipment after receiving the ARP response message of the next hop equipment through a control channel between the CES single disk and the master control disk, and sends TDM parameter information and network parameter information required by the CES service to a CES service chip of the CES single disk; wherein the network parameter information includes: a destination IP address of the remote CES device, an IP address of the next hop device and an MAC address of the next hop device;

the main control panel is used for sending the ARP request message to a third port of the exchange chip through two-layer exchange by the exchange chip of the main control panel; wherein, the MAC address learning function of the first port of the exchange chip is closed; and the switching chip of the master control disk receives an ARP response message replied by the next hop equipment from the third port, learns the MAC address of the next hop equipment from the ARP response message, stores the learned MAC address in an MAC address table, and redirects the ARP response message to the first port of the switching chip by matching an ARP protocol number with a target IP address through an Access Control List (ACL).

4. The distributed system of claim 2, wherein:

the CES single disk is used for receiving TDM signals from any TDM interface through a CES service chip of the CES single disk, packaging the TDM signals into IP messages, and then sending the IP messages to a second port of the switching chip of the master control disk through a data channel from a second interface of the CES service chip;

the main control panel is used for looking up an MAC address table through an exchange chip of the main control panel, sending the IP message to a network interface of the main control panel through a third port of the exchange chip and outputting the IP message to a PSN network from the network interface; and the switching chip learns the MAC address of the next-hop equipment on the third port in the ARP interaction flow.

5. The distributed system of claim 2, wherein:

the main control panel is configured to receive, through a third port of an exchange chip of the main control panel, a CES service packet sent by a next hop device from a network interface of the main control panel, directly forward the CES service packet to a second port of the exchange chip according to a destination MAC address, and send the CES service packet to a CES interface of a service chip of the CES single panel through a data channel between the second port of the exchange chip and the CES single panel; the MAC address of the CES single disk is used as a static MAC to be configured to a second port of a switching chip of a master control disk in advance;

and the CES single disk is used for extracting TDM payload information from a CES service message received from the second interface through a CES service chip of the CES single disk, converting the TDM payload information into a TDM signal, and transmitting the TDM signal to the TDM interface of the CES single disk from the first interface of the CES service chip.

6. The distributed system of claim 2, wherein:

and the CES single disk is further used for acquiring a new MAC address of the next-hop device again through an ARP request by a control module of the CES single disk after the MAC address of the next-hop device stored on the CES single disk is aged, and updating the network parameter of the CES service chip of the CES single disk according to the new MAC address.

7. The distributed system of claim 2, wherein:

the CES single disc is also used for the control module of the CES single disc to pass through the control channel of the CES single disc regularly pings the remote CES equipment, after the ping request reaches the preset times continuously overtime, the control module of the CES single disc judges that a fault occurs, controls the CES service chip of the CES single disc to stop sending CES messages to the PSN network, and when the fault is recovered, the control module of the CES single disc controls the CES service chip of the CES single disc to recover to send CES messages to the PSN network.

8. A method of implementing a circuit emulation service, comprising:

a circuit emulation service CES single disk or any one of a plurality of CES single disks obtains configuration parameters required by the CES service through a control channel between the CES single disk and a master control disk; the CES single disk is provided with one or more time division multiplexing TDM interfaces, and the master control disk is provided with a PSN network interface; the configuration parameters at least include: PSN network parameters;

after receiving a CES message from a PSN network interface of a master control disk, a master control disk sends the CES message to a CES single disk through a data channel between the CES single disk and the master control disk according to the CES message, the CES single disk extracts TDM information from the CES message and converts the TDM information into a TDM signal, and the TDM signal is forwarded through a TDM interface of the CES single disk.

9. The method of claim 8, wherein:

a control channel of any CES single disk is established between a control module of the CES single disk and a first port of the switch chip; and the data channel of the CES single disk is established between the CES service chip of the CES single disk and the second port of the switching chip.

10. The method of claim 9, wherein:

the method for obtaining configuration parameters required by a CES service through a control channel between a CES single disk and a master control disk by using any one of the circuit emulation service CES single disk or the multiple CES single disks includes:

for any CES single disk, the control module of the CES single disk sends an address resolution protocol ARP request message to a first port of an exchange chip of a main control disk, and the exchange chip of the main control disk sends the ARP request message to a third port of the exchange chip through two-layer exchange; wherein, the MAC address learning function of the first port of the exchange chip is closed;

an exchange chip of the master control disk receives an ARP response message replied by next hop equipment from a third port, learns the MAC address of the next hop equipment from the ARP response message, stores the learned MAC address in an MAC address table, matches an ARP protocol number with a target IP address through an access control list ACL, and redirects the ARP response message to the first port of the exchange chip;

after receiving the ARP response message through a control channel between the CES single disk and the master control disk, the control module of the CES single disk obtains an MAC address of next-hop equipment from the ARP response message, and issues TDM parameter information and network parameter information required by a CES service to a CES service chip of the CES single disk; wherein the network parameter information includes: a destination IP address of the remote CES device, an IP address of the next hop device, and a MAC address of the next hop device.

11. The method of claim 9, wherein:

any one CES single disk encapsulates TDM signals extracted from a TDM interface of the CES single disk into CES service messages, then the CES service messages are sent to a master control disk through a data channel between the CES single disk and the master control disk, and the master control disk forwards the CES messages through a PSN network interface of the master control disk, wherein the CES service messages include:

a CES service chip of a CES single disk receives a TDM signal from any TDM interface, encapsulates the TDM signal into an IP message, and then sends the IP message to a second port of a switching chip of a master control disk from a second interface of the CES service chip through a data channel; and the exchange chip checks the MAC address table, sends the IP message to a network interface of a main control panel through a third port of the exchange chip and outputs the IP message to a PSN network from the network interface.

12. The method of claim 9, wherein:

after receiving a CES message from a PSN network interface of a master control disk, a master control disk sends the CES message to a CES single disk through a data channel between the CES single disk and the master control disk according to the CES message, the CES single disk extracts TDM information from the CES message and converts the TDM information into a TDM signal, and the TDM signal is forwarded through a TDM interface of the CES single disk, and the method comprises the following steps:

a third port of the switching chip of the master control disk receives a CES service message sent by the next hop of equipment from a network interface of the master control disk, directly forwards the CES service message to a second port of the switching chip according to a destination MAC address, and sends the CES service message to a second interface of the service chip of the CES single disk through a data channel between the second port of the switching chip and the CES single disk;

after receiving the CES service message from the second interface, the CES service chip of the CES single disk extracts TDM payload information from the CES service message and converts the TDM payload information into a TDM signal, and the TDM signal is sent to the TDM interface of the CES single disk from the first interface of the CES service chip;

and the MAC address of the CES single disk is configured as a static MAC to a second port of the switching chip of the master control disk in advance.

13. The method of claim 9, wherein the method further comprises:

and after the MAC address of the next-hop equipment stored on the CES single disk is aged, the control module of the CES single disk acquires the new MAC address of the next-hop equipment again through an ARP request, and updates the network parameters of the CES service chip according to the new MAC address.

14. The method of claim 9, wherein the method further comprises: