WO2008037202A1

WO2008037202A1 - Method and apparatus for transmitting data

Info

Publication number: WO2008037202A1
Application number: PCT/CN2007/070478
Authority: WO
Inventors: Di Zhou; Jun Wang
Original assignee: Hangzhou H3C Technologies Co., Ltd.
Priority date: 2006-09-25
Filing date: 2007-08-15
Publication date: 2008-04-03
Also published as: CN1964345B; CN1964345A

Abstract

A method for transmitting data, which includes: establishing the association relation between the multicast stream and the storage apparatus; determining the storage apparatus corresponding to the data which will be transmitted in the form of multicast stream, according to the established association relation; transforming the data which will be transmitted in the form of multicast stream to the data which will be transmitted in the form of unicast stream with the destination address of said corresponding storage apparatus, according to the protocol supported by the determined storage apparatus, and transmitting said data to said corresponding storage apparatus. An apparatus for transmitting data is provided. It realizes network storage using multicast stream, reducing the workload of the transmitter effectively, and reducing the cost of the transmitter.

Description

Data transmission method and data transmission device

TECHNICAL FIELD The present invention relates to data transmission technologies, and more particularly to data transmission methods and data transmission devices. Background of the invention

Internet Protocol (IP) Multicast refers to the transmission of data packets to a subset of nodes in the network in an IP network. This subset of nodes is called a Multicast Group. In the IP multicast process, the sender that serves as the multicast source sends a multicast stream with the multicast address as the destination address. All receivers that join the multicast address can receive the multicast stream sent by the multicast source. .

The Internet Small Computer System Interface (ISCSI) protocol is a Small Computer System Interface (SCSI) protocol based on Transmission Control Protocol (TCP). The ISCSI protocol is currently a widely used network storage protocol in storage systems. SCSI commands and data are transmitted over the IP network between the transmitting end as a data source and the storage device for storing data in the storage system to implement network storage of data. During transmission, a session connection between the sender and the storage device is established, and the sender and the storage device interact with the SCSI command and data through the established session connection. The way the ISCSI protocol transmits data is unicast.

When the sender sends data to multiple receivers in multicast mode and also sends data to the storage device through unicast mode, the sender sends the multicast stream as a multicast source and sends the ticket as a unicast source. Broadcast.

FIG. 1 is a schematic structural diagram of a system for simultaneously transmitting a multicast stream and a unicast stream. As shown in Figure 1, in the system, the transmitting end 110 serves as both a multicast source and a unicast source, respectively. The multicast address and the unicast address are encapsulated into a multicast stream and a unicast stream, and then sent out. The packets constituting the multicast stream are usually in accordance with the user datagram protocol.

(UDP, User Datagram Protocol) or TCP/IP packet; The packet that constitutes a unicast stream is an ISCSI-compliant packet, and the unicast stream is an ISCSI stream. Since the transmission of the ISCSI stream requires a session connection between the sender 110 and the storage device 140, when the ISCSI stream is sent, the encapsulated ISCSI stream is output through the corresponding outbound interface of the established tongue connection. The thick solid line with arrows in Figure 1 indicates the direction of transmission of the multicast stream, and the dashed line with arrows indicates the direction of transmission of the ISCSI stream.

After receiving the multicast stream, the network device 120 forwards the received multicast stream to the receiving end 130 or the network device directly connected to the network device 120 according to the multicast entry that is saved for forwarding the multicast stream. 120. After receiving the ISCSI stream, the network device 120 sends the ISCSI stream to the storage device 140 either directly or through other network devices 120 connected to the network device through the session connection. The multicast entry is also called a (S, G) multicast entry, where G represents the multicast address as the destination address, and S represents the source address of the multicast sent to the multicast address G, (S, G) The multicast address, multicast address, and its inbound interface list and outbound interface list are saved in the multicast entry.

The receiving end 130 is configured to receive a multicast stream, and perform corresponding operations according to the received multicast stream, for example, display.

Storage device 140 is used to store the received ISCSI stream. Specifically, the storage device 140 performs storage operations by parsing the received ISCSI stream to obtain SCSI commands, data, responses, and the like.

As can be seen from the above, the multicast stream is ultimately sent to the receiving end 130 via one or more network devices 120. A unicast stream, exemplified by an ISCSI stream, is ultimately sent to storage device 140 via one or more network devices 120.

The system structure shown in Figure 1 can be applied to many display and storage systems for media streams. Medium. For example, many cities now set up monitoring systems at key points such as various business units and major transportation routes, and use storage devices to store recorded video data. Suppose a city public security bureau has 20 sub-bureaus, each sub-office has 25 police stations, and each police station has 1000 cameras. Then, each camera is a multicast source, and it is sent to the city bureau in the form of multicast data stream. The real-time monitoring host of the branch office and the police station sends the recorded video data for monitoring; in order to store the recorded video data in the storage device, each camera is also a unicast source, and sends the unicast stream to the storage device. The recorded video data is stored for it.

2 is a schematic structural diagram of a conventional video monitoring and storage system. As shown in FIG. 2, the system adopts the structure shown in FIG. 1. The thin solid line with arrows in FIG. 2 indicates the internal modules of the transmitting end and the receiving end. The direction of the output transmission. The transmitting end 110 is composed of a camera 111 and a hardware encoder 112. The camera 111 collects the video data and sends it to the hardware encoder 112. After the video data is encoded and correspondingly encapsulated by the hardware encoder 112, the multicast stream and the unicast stream are obtained, and then sent to the network device 120 connected thereto.

The receiving end 130 is composed of a hardware decoder 132 and a display device 133. The hardware decoder 132 performs a decoding operation on the multicast data stream and transmits it to the display device 133 for display. Of course, if the display device is a display device 131 with a decoding function, such as a computer, the display device 131 with decoding function will directly decode and display the multicast data stream received from the network device 120.

It can be seen that in the existing system for transmitting the multicast stream and the unicast stream, since the unicast stream sent by the sender can only be used to perform the write operation on the storage device 140 to implement network storage, the sender 110 needs to simultaneously send the multicast stream. And the unicast stream has high performance requirements on the transmitting end 110, and the link bandwidth of the transmitting end 110 communicating with the external device is also heavy. For example, in the above video surveillance and storage system, the amount of data to be processed by the transmitting end is quite large, and the transmitting end needs to perform encapsulation of the huge amount of data and multicast and unicast. Therefore, the transmitting end bears a lot. Difficult data delivery tasks. In order to improve the performance of the sender, you need A higher performance device is configured for the sender, resulting in an increase in cost. Summary of the invention

In view of this, the present invention provides a data transmission method capable of realizing network storage by using a multicast stream.

The method includes: establishing an association relationship between a multicast stream and a storage device;

Determining, according to the established association relationship, a storage device corresponding to the data to be transmitted in the form of a multicast stream;

Converting the data to be transmitted in the form of a multicast stream to the data to be transmitted in the form of a unicast stream with the corresponding storage device as the destination address, and transmitting the data to the corresponding storage device, according to the protocol supported by the storage device. .

The establishing the association relationship between the multicast stream and the storage device includes: creating a tongue connection between the network device for forwarding the multicast stream and the storage device; establishing the session connection and forwarding the multicast stream Association between multicast entries. The determining, by the network device, the storage device corresponding to the data to be transmitted in the form of the received multicast stream, according to the established association relationship, includes:

Finding a corresponding multicast entry according to the data to be transmitted in the form of a multicast stream;

When it is determined that the discovered multicast entry has a corresponding session connection according to the established association relationship, the storage device connected to the corresponding session connection is determined as the storage device corresponding to the data to be transmitted in the form of the multicast stream.

The data to be transmitted in the form of a unicast stream in which the data to be transmitted in the form of a multicast stream is converted to the destination address of the corresponding storage device includes:

Replacing the multicast address of the data to be transmitted in the form of the multicast stream by using the address of the storage device connected to the corresponding session connection;

The number of to-be-transmitted forms in the form of a multicast stream according to a protocol supported by the connected storage device According to the encapsulation, data to be transmitted in the form of a unicast stream with the corresponding storage device as a destination address is generated.

After the determining the storage device corresponding to the data to be transmitted in the form of the multicast stream, the data to be transmitted in the form of the multicast stream is converted into a unicast stream in the form of the corresponding storage device. Before or after the data is transmitted, the method further includes: adding the corresponding session connection as a virtual interface to the outbound interface list of the found multicast entry;

The sending to the corresponding storage device is: sending the to-be-transmitted data in the form of the generated unicast stream to the corresponding storage device by using the virtual interface in the join multicast entry.

Preferably, the method further includes: forwarding the to-be-transmitted data in the form of the received multicast stream according to the outbound interface except the virtual interface in the found multicast entry.

Preferably, the method further includes: determining, according to the association relationship between the established session connection and the multicast entry, whether the found multicast entry has a corresponding session connection, and if yes, performing the determining The operation of the storage device corresponding to the data to be transmitted in the form of a multicast stream; otherwise, the data to be transmitted in the form of the received multicast stream is forwarded according to the outbound interface in the found multicast entry.

The session connection is an ISCSI session connection; the storage device is a storage device that supports the ISCSI protocol.

The present invention also provides a data transmission device capable of implementing network storage by using a multicast stream. The device includes: an association establishing unit, a storage unit, and a multicast stream processing unit, wherein

The association relationship establishing unit is configured to establish an association relationship between the multicast stream and the storage device;

The multicast stream processing unit is configured to determine, according to the association relationship established by the association relationship establishing unit, a storage device corresponding to the data to be transmitted in the form of a multicast stream; ^^ according to the protocol supported by the determined storage device, the group The data to be transmitted in the form of broadcast is converted into the corresponding storage The storage device is in the form of a unicast stream of the destination address to be transmitted and transmitted.

Preferably, the device further comprises a storage unit;

The association establishing unit further sends the established association relationship to the storage unit;

The storage unit is configured to store the received association relationship.

The association establishing unit includes a session establishing module and an association module, where the session establishing module is configured to create a tongue connection between the data transmission device and the storage device where the node is located;

The association module is configured to establish an association relationship between a session connection created by the session establishment module and a multicast entry for forwarding a multicast stream, and send the established association relationship to the storage unit;

The storage unit further stores each multicast entry, and stores the received association relationship between the session connection and the multicast entry.

The multicast stream processing unit includes a lookup determination module, a processing module, and a conversion sending module, where

The search and judgment module is configured to search for a multicast entry corresponding to the data to be transmitted in the form of a multicast stream from the storage unit; and determine, according to the association relationship between the session connection and the multicast entry saved by the storage unit, Whether the multicast entry has a corresponding session connection, and sends the determination result to the processing module;

The conversion sending module decapsulates the multicast stream to obtain data to be transmitted, and the used data to be transmitted is encapsulated into data to be transmitted in a unicast stream conforming to the protocol supported by the storage device; according to the received group The virtual interface in the broadcast entry sends the generated data to be transmitted in the form of a unicast stream.

Preferably, the conversion sending module is further configured to: according to the received multicast entry The outbound interface other than the virtual interface forwards the data to be transmitted in the form of a multicast stream.

The present invention can implement network storage by using a multicast stream. Specifically, the present invention has the following beneficial effects:

After receiving the multicast stream from the sending end, the network device of the present invention converts the multicast stream into a unicast stream with the corresponding storage device as the destination address and sends the multicast stream according to the protocol supported by the storage device corresponding to the multicast stream. To the storage device, network storage using the multicast stream is realized.

At the same time, since the transmitting end only needs to send the multicast stream, the performance requirement of the transmitting end is reduced, and the transmitting end can be implemented by a device with a lower cost. At the same time, the transmitting end does not need to send a unicast stream, which reduces the link bandwidth burden of the transmitting end to communicate with the external device.

In addition, before being converted to a unicast stream, the network device through which the multicast stream flows only needs to forward the multicast stream, so that the existing network device between the sender and the storage device needs to forward the unicast stream and the group at the same time. The problem of heavy forwarding burden caused by broadcast streaming. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a system for simultaneously transmitting a multicast stream and a unicast stream.

FIG. 2 is a schematic structural diagram of a conventional video monitoring and storage system.

FIG. 3 is a schematic flowchart of a data transmission method according to the present invention.

FIG. 4 is a flowchart of a data transmission method according to an embodiment of the present invention.

FIG. 5 is an ISCSI package format in an embodiment of the present invention.

FIG. 6 is a schematic structural diagram of a data transmission system according to an embodiment of the present invention.

FIG. 7 is a schematic structural diagram of a data transmission device according to an embodiment of the present invention. Mode for carrying out the invention

The present invention will be described in detail below with reference to the accompanying drawings and embodiments. The present invention is a data transmission scheme, and the basic idea is: after receiving a multicast stream, the network device converts the multicast stream to a corresponding storage device according to a protocol supported by the storage device corresponding to the multicast stream. A unicast stream of the destination address is sent to the corresponding storage device. Then, the storage device can use the converted unicast stream for network storage.

FIG. 3 is a schematic flowchart of a data transmission method according to the present invention. As shown in FIG. 3, the method includes the following steps:

Step 301: Establish an association relationship between the multicast stream and the storage device.

Step 302: Determine, according to the established association relationship, a storage device corresponding to the data to be transmitted in the form of a multicast stream.

Step 303: Send the unicast stream supported by the storage device corresponding to the data to be transmitted in the form of a multicast stream to the corresponding storage device.

As can be seen from the flow shown in FIG. 3, the present invention implements network storage using the multicast stream by converting the multicast stream to be stored into a unicast stream and then transmitting the data to the storage device. Since the sender only needs to send the multicast stream, the performance requirements of the sender are reduced, and the sender can be implemented by a lower cost device. At the same time, the transmitting end does not need to send a unicast stream, which reduces the bandwidth burden of the link between the transmitting end and the external device.

The data transmission method of the present invention can be applied to a network device that uses an ISCSI session to send an ISCSI stream to a storage device to implement network storage. The network device can be a Layer 3 device, such as a Layer 3 switch, a Layer 3 router, or the like.

The data transmission method of the present invention will be described in detail below by taking a multicast stream in a Layer 3 device and storing it in a storage device through an ISCSI session.

FIG. 4 is a flowchart of a data transmission method according to an embodiment of the present invention. As shown in Figure 4, the method includes the following steps:

Step 401: Configure an ISCSI session on a Layer 3 device configured with a multicast routing protocol. The association relationship between the (S, G) multicast entries used to forward the multicast stream.

In this step, an ISCSI session connection is established between the Layer 3 device and the corresponding resource of the storage device, and the established ISCSI session connection is associated with the (S, G) multicast entry. Since the multicast stream is associated with the (S, G) multicast entry, the (S, G) multicast entry is associated with the ISCSI session connection, and the ISCSI session connection is associated with the storage device, then this step is established after execution. The relationship between the multicast stream and the storage device. At this point, the (S, G) multicast entry is unchanged. Table 1 shows the composition of the (S, G) multicast entry. As shown in Table 1, the (S, G) multicast entry includes the source address, multicast address, inbound interface list, and outbound interface list. Vlan - interfacel5 ( 10.10.10.1 ) in the inbound interface list indicates the inbound interface name ( Vlan - interfacel5 ) and the inbound interface IP address ( 10.10.10.1 ); Vlan - interface25 ( 11.11.11.1 ) in the outbound interface list indicates The interface name (Vlan - interface25) and the outbound interface IP address (11.11.11.1).

Table 1

The multicast routing protocols configured on the Layer 3 device include: Distance Vector Multicast Routing Protocol

(DVMRP, Distance Vector Multicast Routing Protocol), Protocol Independent Multicast-Dense Mode (PIM-DM) protocol, Protocol Independent Multicast-Sparse Mode (PIM-SM, Protocol Independent Multicast-Sparse) Mode) Ten meetings and so on.

The corresponding resources on the storage device include the IP address and port number of the storage device, and may also include the storage device name.

Step 402: The layer 3 device receives the multicast stream from the sender.

Step 403: Find a corresponding (S, G) multicast entry according to the received multicast stream. Step 404: Determine, according to the association relationship established in step 401, that the received multicast stream (S, G) Whether the multicast entry has a corresponding ISCSI session connection; if yes, step 405 is performed; otherwise, step 408 is performed.

Step 405: Add the corresponding ISCSI session connection as an ISCSI virtual interface to the outbound interface list of the discovered (S, G) multicast entry. The virtual interface refers to the interface occupied by the established ISCSI tongue. The interface occupied by the ISCSI port is called the ISCSI virtual interface. The interface used by the ISCSI module is different from the original forwarding interface in the outbound interface list of the (S, G) multicast entry. An ISCSI virtual interface is a logical interface that can be understood as an identifier. In the process of forwarding a multicast stream by using the (S, G) multicast entry, when the outbound interface is an ISCSI virtual interface, it indicates that the multicast stream to be forwarded is converted into an ISCSI stream, and then sent to the storage through the ISCSI virtual interface. device.

Table 2 shows the (S, G) multicast entries after the ISCSI virtual interface is added to Table 1. As shown in Table 2, the ISCSI virtual interface interface iscsi ( 12.12.12.1 ) is added to the outbound interface list of the (S, G) multicast entry with the multicast address 225.1.1.111. Where, interface iscsi is virtual. Interface name, 12.12.12.1 indicates the IP address of the virtual interface.

Table 2

Step 406: Replace the multicast address of the received multicast stream with the address of the connected storage device by using the corresponding ISCSI session connection, and perform ISCSI encapsulation on the address-replaced multicast stream data to generate an ISCSI stream.

In this step, for the multicast stream to be replaced, the multicast stream is first decapsulated to obtain the payload of the data to be transmitted, and the address of the storage device is used as the destination address, and the data payload to be transmitted is ISCSI encapsulated. The data to be transmitted in the form of an ISCSI stream is obtained. Since the destination device of the ISCSI stream is a storage device, the storage device performs according to the received ISCSI stream. Data storage, therefore, does not focus on the source address when encapsulating. Therefore, the address of the Layer 3 device can be used, or the source address in the original multicast stream can be used as the source address of the ISCSI stream. The ISCSI package is available in an existing ISCSI package format. Figure 5 shows an ISCSI package format. As shown in Figure 5, the ISCSI packet includes a 48-byte ISCSI header and ISCSI data. The ISCSI data carries data to be transmitted, such as SCSI commands, management functions, command responses, data to be stored, and the like. Then, the ISCSI data is sequentially added with a 20-byte TCP header, and the 20-byte IP header constitutes an IP packet, and then a 14-byte Ethernet header and a 4-byte Ethernet tail are respectively added at the beginning and the end of the IP packet. , thus forming an Ethernet frame. The length of the ISCSI data portion is related to the length of the data to be transmitted.

The ISCSI package in this step can be implemented in software. In order to reduce the consumption of Layer 3 device resources, hardware devices connected to Layer 3 devices dedicated to ISCSI encapsulation can be used. For example, the package processing can be implemented by programming an Application Specific Integrated Circuit (AISC), or by using an ISCSI Host Bus Adapter (HBA).

Step 407: Send the encapsulated ISCSI stream to the storage device by adding the virtual interface in the (S, G) multicast entry.

Step 408: Forward the multicast stream according to the outbound interface in the (S, G) multicast entry. The outbound interface of the forwarding multicast stream does not include a virtual interface for forwarding the ISCSI stream. For example, the multicast stream can be forwarded using the outgoing interface Vlan - interface25 ( 11.11.11.1 ) shown in Table 2.

At this point, the process ends.

Steps 406 to 407 are steps of forwarding the ISCSI stream, and step 408 is the step of forwarding the multicast stream. There is no obvious sequence between the two parts. You can also forward the multicast stream first, then convert and send the unicast stream. In an actual application, the forwarding sequence may be determined according to the outbound interface list of the (S, G) multicast entry. Take the (S, G) multicast entry shown in Table 2 as an example. When the outbound interface is Vlan - interface25 ( 11.11.11.1 ), go to step 408 to forward the packet. If the outbound interface is the virtual interface interface iscsi ( 12.12.12.1 ), replace the group address 225.1.1.111 with the storage device address, encapsulate the multicast stream data into an ISCSI stream, and use the virtual interface and storage. The ISCSI session connection between the settings sends the encapsulated ISCSI stream to the storage device.

In order to implement the above data transmission method, an embodiment of the present invention provides a data transmission system. FIG. 6 is a schematic structural diagram of a data transmission system according to an embodiment of the present invention. As shown in FIG. 6, the system includes: a transmitting end 610, a network device 620, a receiving end 630, a storage device 640, and a data transmission device 650.

The sender 610 is a multicast source. The transmitting end 610 encapsulates the data to be transmitted into a multicast stream according to the configured multicast address.

Network device 620 forwards the received multicast stream. It receives the multicast stream from the sender 610 or other network device 620 directly connected to the network device 620 and forwards it to the receiver 630 and/or to the network device 620 directly connected to the network device 620.

The data transmission device 650 also belongs to a network device, which has the basic functions of a network device and is capable of forwarding a multicast stream. The data transmission device 650 further stores a pre-established association relationship between the multicast stream and the storage device, and determines a storage device corresponding to the data to be transmitted in the form of a multicast stream according to the saved association relationship, and supports the storage device according to the determined storage device. The protocol converts the data to be transmitted in the form of a multicast stream into data to be transmitted in the form of a unicast stream with the determined storage device as the destination address, and sends the data to the determined storage device 640.

The storage device 640 receives data from the external unicast stream and saves it.

FIG. 7 is a schematic structural diagram of a data transmission device according to an embodiment of the present invention. As shown in FIG. 7, the data transmission device 700 includes: an association establishing unit 710, a storage unit 720, and a multicast stream processing unit 730.

The association relationship establishing unit 710 is configured to establish an association relationship between the multicast stream and the storage device, and send the established association relationship to the storage unit 720. The storage unit 720 is configured to store an association relationship between the multicast stream and the storage device. If it is not necessary to permanently save the association relationship established by the association establishing unit 710, the storage unit 720 may not be included in the data transmission device 700. Then, the multicast stream processing unit 730 directly uses the association relationship established by the association relationship establishing unit 710.

The multicast stream processing unit 730 is configured to determine, according to the association relationship acquired from the storage unit 720, a storage device corresponding to the data to be transmitted in the form of a multicast stream, and to wait for the multicast stream according to the determined protocol supported by the storage device. The transmission data is converted into data to be transmitted in the form of a unicast stream with the determined storage device as a destination address, and transmitted to the outside.

The association relationship establishing unit 710 specifically includes a session establishing module 711 and an association module 712. among them,

The session establishing module 711 is configured to create a session connection between the data transmission device and the storage device where the data is located. For storage devices that support the ISCSI protocol, the session connection established by the module is an ISCSI connection.

The association module 712 is configured to establish an association relationship between the session connection created by the session establishment module 711 and the (S, G) multicast entry, and send the established association relationship to the storage unit 720. For a storage device that supports the ISCSI protocol, the module establishes the association relationship between the ISCSI session connection and the (S, G) multicast entry.

The storage unit 720 specifically stores (S, G) multicast entries, and association relationships between session connections and (S, G) multicast entries.

The foregoing multicast stream processing unit 730 specifically includes a lookup determining module 731, a processing module 732, and a conversion sending module 733, where

The search judging module 731 is configured to receive data to be transmitted in the form of a multicast stream from the outside, and search for the data to be transmitted in the form of the received multicast stream according to the (S, G) multicast entry obtained from the storage unit 720. The (S, G) multicast entry determines whether the found (S, G) multicast entry has a corresponding session connection according to the association relationship obtained by the storage unit 720. The result of the determination is sent to the processing module 732.

The processing module 732 is configured to: when the received judgment result is that the found (S, G) multicast entry has a corresponding session connection, add the corresponding session connection as a virtual interface to find the

(S, G) in the outbound interface list of the multicast entry, the modified (S, G) multicast entry is sent to the conversion sending module 733; when the received judgment result is that there is no corresponding session connection, the The modified (S, G) multicast entry is sent to the conversion sending module 733.

The conversion sending module 733 is configured to forward the multicast stream according to the received (S, G) multicast entry. Specifically, for the modified (S, G) multicast table, the multicast stream is decapsulated, and the data to be transmitted is obtained, and the address of the storage device connected by the corresponding session connection is used as the destination address, and the obtained The transport data is encapsulated into a unicast stream that conforms to the protocols supported by the storage device. The generated unicast stream is sent to the storage device in the session connection through the virtual interface in the (S, G) multicast entry. The outbound interface except the virtual interface is sent through the (S, G) multicast entry. In the case of multicast streaming, the existing forwarding mode is used to forward the multicast stream. In addition, for the multicast determination that the lookup determination module 731 determines that there is no corresponding session connection, the conversion sending module 733 is based on the unmodified

(S, G) Each outgoing interface in the outbound interface list of the multicast entry forwards the multicast stream using the existing forwarding mode.

In Figure 6, the multicast stream sent by the sender 610 passes through the network device 1 and the network device 2 to the data transmission device 650, which is converted into a unicast stream by the data transmission device 650. In practice, the data transmission device 650 can also be placed at any node through which the multicast stream flows, for example, at the location of the network device 1 or the network device 2. When the data transmission device 650 is close to the storage device, each network device 620 between the data transmission device 650 and the transmitting end 610 does not need to forward the unicast stream, which reduces the forwarding burden of these network devices.

The video monitoring and storage system mentioned in the background art can be implemented by the data transmission system in the embodiment of the present invention. As shown in FIG. 6, the transmitting end 610 is composed of a camera 611 and a hardware encoder 612. The hardware encoder 612 only enters the video data collected by the camera 611. The lines are encoded and encapsulated into a multicast stream that is sent to the network device 620 to which it is connected. Network device 620 is responsible for forwarding the multicast stream. The network device connected to the storage device 640 is implemented by the data transmission device 650 in the embodiment of the present invention. The data transmission device 650 converts the received multicast stream into a unicast stream, and sends the converted unicast stream to the storage device 640. The received multicast stream is also forwarded to the receiving end 630 connected thereto. The hardware decoder 632 in the receiving end 630 decodes the data in the form of a unicast stream, displays it by the display device 633, or directly decodes and displays it by the display device 631 with the decoding function.

It can be seen that, by using the data transmission scheme of the present invention, the multicast stream is converted into a unicast stream on a network device that flows from the sending end 610 to the storage device 640, and then the storage module 640 can utilize the converted single. The broadcast stream performs network storage without the sender 610 sending a unicast stream. At the same time, the hardware encoder 612 in the transmitting end 610 only needs to process the multicast stream, which reduces the burden on the hardware encoder 612. Before being converted to a unicast stream, the network device through which the multicast stream flows only needs to forward the multicast stream, which avoids the heavy forwarding load caused by the existing network device needing to forward the unicast stream and the multicast stream at the same time. problem.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalents, improvements, etc., which are made within the spirit and principles of the present invention, should be included in the present invention. Within the scope of protection.

Claims

Claim

1. A data transmission method, the method comprising:

Establish an association relationship between the multicast stream and the storage device.

The method of claim 1, wherein the establishing the association relationship between the multicast stream and the storage device comprises:

Creating a link between the network device for forwarding the multicast stream and the storage device; establishing an association relationship between the session connection and the multicast entry for forwarding the multicast stream.

The method of claim 2, wherein the determining, by the network device, the storage device corresponding to the data to be transmitted in the form of the received multicast stream, according to the established association relationship, includes:

The method according to claim 3, wherein the data to be transmitted in the form of a unicast stream in which the data to be transmitted in the form of a multicast stream is converted to the destination address of the corresponding storage device comprises:

Replacing the multicast address of the data to be transmitted in the form of the multicast stream by using the address of the storage device connected to the corresponding session connection; The data to be transmitted in the form of a multicast stream is encapsulated according to the protocol supported by the connected storage device, and the data to be transmitted in the form of a unicast stream with the destination storage device as the destination address is generated.

The method according to claim 3, after the determining the storage device corresponding to the data to be transmitted in the form of a multicast stream, and converting the data to be transmitted in the form of a multicast stream to the corresponding Before or after the data to be transmitted in the unicast stream of the destination address, the method further includes: adding the corresponding session connection as a virtual interface to the outbound interface list of the found multicast entry;

The method according to claim 5, wherein the method further comprises: forwarding the data to be transmitted in the received multicast stream according to the outbound interface except the virtual interface in the found multicast entry.

The method of claim 3, wherein the method further comprises: determining, according to the association relationship between the established session connection and the multicast entry, whether the found multicast entry has a corresponding a session connection, if yes, performing the operation of determining the storage device corresponding to the data to be transmitted in the form of a multicast stream; otherwise, forwarding the received multicast stream according to the outbound interface in the found multicast entry transfer data.

The method of claim 2, wherein the session connection is an ISCSI session connection; and the storage device is a storage device supporting the ISCSI protocol.

A data transmission device, comprising: an association relationship establishing unit and a multicast stream processing unit, wherein

The multicast stream processing unit is configured to establish an association established by the unit according to the association relationship a relationship, the storage device corresponding to the data to be transmitted in the form of a multicast stream is determined; and the data to be transmitted in the form of a multicast stream is converted into the destination address of the corresponding storage device according to the protocol supported by the storage device determined by the storage device. The data to be transmitted in the form of a unicast stream is sent.

10. The device of claim 9, wherein the device further comprises a storage unit;

The storage unit is configured to store the received association relationship.

The device according to claim 10, wherein the association establishing unit includes a session establishing module and an association module, where

The session establishing module is configured to create a tongue connection between a data transmission device and a storage device;

The device according to claim 11, wherein the multicast stream processing unit includes a lookup determination module, a processing module, and a conversion sending module, where

The processing module adds the corresponding session connection as a virtual interface to the found multicast entry when the received judgment result is that the found multicast entry has a corresponding session connection. In the outbound interface list, the modified multicast entry is sent to the conversion sending module; the conversion sending module decapsulates the multicast stream, obtains data to be transmitted, and uses the data to be transmitted to be encapsulated into a matching The data to be transmitted in the form of a unicast stream of the protocol supported by the storage device; the data to be transmitted in the form of a unicast stream generated according to the virtual interface in the received multicast entry is sent out.

The device according to claim 12, wherein the conversion sending module is further configured to: forward the to-be-transmitted form in the form of a multicast stream according to the outbound interface except the virtual interface in the received multicast entry data.