JP2014165743A - Distribution server and program therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a signal processing technique easily compatible with a multiprotocol by efficiently executing distribution processing in a scale-out type network server system.SOLUTION: A distribution server 20 includes in a transport layer: an external transport layer receiver 222 for receiving a packet to determine whether or not there is an existing external connection 223 that stores the packet data; a distribution destination determination unit 221 for referring to connection information 226 having the external connection 223 associated with an internal connection 225, acquiring the internal connection 225 associated with the existing external connection 223, and handing over the packet data stored in the existing external connection 223 to the internal connection 225; and a transport layer transfer unit 224 for transmitting the packet data, handed over to the internal connection 225, to a processing server 30 of a transfer destination, associated with the internal connection 225.

Description

  The present invention relates to a technique for efficiently executing distributed processing in a scale-out type network server system.

  In recent years, studies have been conducted on adopting a scale-out type system that has been conventionally used in Web servers and the like for network server systems that execute communication control (see Non-Patent Document 1). Non-Patent Document 1 discloses a scale-out type server cluster configuration method using a consistent hash method. In this server cluster configuration method, a server cluster is configured by three elements of a load balancer, a distribution server, and a processing server, so that the system configuration can be flexibly increased by dynamically increasing and decreasing the number of servers, and a network server system (Non-Patent Document 1). Is described as a session control server), and a technology that achieves both high availability is disclosed.

  The load balancer distributes packets to an arbitrary distribution server according to a simple rule such as round robin. The distribution server determines to which processing server the session data (data used for session management etc.) of the packet received from the load balancer is managed, and forwards the packet to the processing server in charge of managing the session data . The processing server performs signal processing according to the received packet, and returns the processing result as response information.

Michio Irie, 4 others, “A study on dynamic configuration change in a scale-out type session control server”, IEICE Technical Report, The Institute of Electronics, Information and Communication Engineers, March 2011, NS2010-236, p. 407-410

  Non-Patent Document 1 discloses a case where the scale-out type server cluster configuration method is applied to an SIP (Session Initiation Protocol) server which is one of network server systems. However, various servers (for example, a session control server, a DNS (Domain Name System) server, an authentication server, etc.) exist in the network server system, and their protocols are various. No signal processing technology that can easily cope with the various protocols (multiprotocols) while suppressing an increase in processing overhead and processing delay associated with distributed processing is not disclosed.

  Therefore, an object of the present invention is to provide a signal processing technique that can efficiently execute distributed processing and can easily cope with multi-protocols in a scale-out type network server system.

  The present invention determines a transfer destination processing server for a received packet, generates at least one distribution server for transmitting the packet to the transfer destination processing server, and generates and returns response information for the received packet. The distribution server in the network server system having the processing server, a storage unit storing connection information in which an external connection and an internal connection are associated with each other, and an existing external device that receives the packet and stores the packet data When it is determined by the external transport layer receiving unit of the transport layer that determines whether there is a connection, and the existing external connection by the external transport layer receiving unit, with reference to the connection information, Packet data stored in the existing external connection A transport layer distribution destination determination unit to be transferred to the internal connection associated with the existing external connection, and the packet data transferred to the internal connection to the transfer destination processing server associated with the internal connection And a transport layer transfer unit of the transport layer.

  According to such a configuration, the distribution server provided in the scale-out type network server system transfers the received packet from the external connection to the internal connection associated with the transfer destination processing server in the transport layer (that is, By modifying the destination address and port), the transfer destination can be reset and transferred. In other words, the distribution server can efficiently execute distributed processing including transfer processing without depending on the difference in protocols, and can easily cope with multi-protocols.

  The distribution server according to the present invention is obtained from the key information of the application layer that analyzes a packet data group indicating the set of packet data and extracts key information used for determining a transfer destination, and the key information. A storage unit that stores transfer destination information that associates a conversion value with the processing server of the transfer destination; and when the external transport layer reception unit determines that there is no existing external connection, a new external Generating a connection, storing the packet data of the received packet in a buffer of the generated external connection, the distribution destination determining unit taking out the packet data group from the buffer, and the packet data group being the key extracting unit The key information is acquired from the key extraction unit, and the transfer destination information is referred to to obtain the key information. Determining a transfer destination processing server associated with the converted value obtained from the key information, and associating the generated external connection with the internal connection associated with the transfer destination processing server, The packet data group of the buffer is delivered, and the transport layer transfer unit transfers the packet data group to the transfer destination processing server.

  According to such a configuration, the key extraction unit of the application layer having a different process with respect to the protocol difference executes only the process of extracting the key information. That is, in the application layer, the key extraction unit only extracts the key information, so even if the protocol is different, the processing overhead of the protocol processing and the MTU (Maximum Transmission Unit) excess problem do not occur. In the transport layer, packet data transfer processing is executed based on the extracted key information. Therefore, the distribution server can efficiently execute distributed processing and easily cope with multi-protocols.

    Note that the invention relating to the program has the same technical features as the above-described distribution server, and has the same effect as the distribution server device, and thus description thereof is omitted.

  According to the present invention, in a scale-out type network server system, it is possible to efficiently perform distributed processing and provide a signal processing technique that can easily cope with multi-protocols.

It is a figure which shows the structural example of a scale-out type network server system. It is a figure which shows the function example of a distribution server. It is a figure which shows the example of a processing flow of a distribution server. It is a figure which shows the function example of a processing server. It is a figure which shows the example of a processing flow of a processing server. It is the figure which showed the function example of the distribution server and the processing server by the software structure, (a) represents the case of a distribution server, (b) represents the case of a processing server. It is a figure which shows an example of the classification of network server system, session data, and key information.

  A mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail with reference to the drawings as appropriate.

First, a configuration example of a scale-out type network server system will be described with reference to FIG.
The scale-out type network server system 800 receives a service request packet from the client device 40 via the network 50, generates response information corresponding to the service request, and sends the response information via the network 50. It has a function to provide a service for replying.

  In FIG. 1, the network server system 800 includes one load balancer 10, a plurality of distribution servers 20, and a plurality of processing servers 30. Note that the number of distribution servers 20 and the number of processing servers 30 may be changed as appropriate according to the number of received packets, and the number of distribution servers 20 may be one.

  The load balancer 10 receives a packet via the network 50 and distributes the packet to an arbitrary distribution server 20 according to a simple rule such as round robin.

  The distribution server 20 determines which processing server 30 is managing session data (session state, results during processing, etc.) relating to a packet received from the load balancer 10, and the processing server 30 in charge of managing the session data. Is determined as a transfer destination, and the packet is transmitted to the processing server 30 of the transfer destination.

  For example, when session data or the like is managed using the consistent hash method, the distribution server 20 includes key information included in a packet (for example, information described in a Call-ID header in SIP (Session Initiation Protocol)). The processing server 30 to which the packet is to be transferred is determined using the hash value generated from the above and the ID space value assigned to each processing server 30. Then, the distribution server 20 transmits the packet to the determined transfer destination processing server 30. In addition, when the processing server 30 is increased / decreased, the distribution server 20 updates the value of the ID space assigned to the processing server 30 in accordance with the increased / decreased setting.

  Since the processing server 30 stores session data and the like used for signal processing of the received packet, the processing server 30 executes signal processing on the packet using the session data and returns the processing result as response information. .

Next, a function example of the distribution server 20 will be described with reference to FIG.
The distribution server 20 includes an application unit 200, an API (Application Programming Interface) 210, a distribution processing unit 220, and a cluster configuration management unit 230.

  The application unit 200 has a function of executing processing at a level higher than the application layer, and includes a key extraction unit 201. The key extraction unit 201 acquires a packet data group from the distribution processing unit 220 via the API 210, analyzes the packet data group, extracts key information used to determine a transfer destination, and returns the extracted key information to the return of the API 210. It has a function of returning a value to the distribution processing unit 220 as a value. Here, the packet data group is a set of packet data in which the original transmission data can be restored in consideration of the case where the size of one transmission data is large and fragmented and transmitted in a plurality of packets. It means that. That is, in this embodiment, when it is described as a packet data group, it indicates packet data of one or more packets. On the other hand, when it is described as packet data, it means packet data of one packet.

The API 210 has a function of receiving a packet data group from the distribution processing unit 220 as an argument and returning the key information extracted by the key extraction unit 201 as a return value. When the API 210 is expressed in Java (registered trademark), for example, it is expressed as follows.
String getKey (Array <byte []>packets);

  The distribution processing unit 220 includes a distribution destination determination unit 221, an external transport layer reception unit 222, and a transport layer transfer unit 224. Note that the external transport layer receiving unit 222 receives a packet from the client device 40, and the transport layer transferring unit 224 transmits the packet to the processing server 30 in the cluster.

  The external transport layer receiving unit 222 has a function of controlling the external connection 223. Specifically, the external transport layer receiving unit 222 has a function of receiving a packet from the client device 40 and determining whether the packet is for a new external connection 223. If it is new, the external transport layer receiving unit 222 newly creates an external connection 223. If not new (that is, existing), the external transport layer receiving unit 222 stores the packet data in the existing external connection 223 and delivers the external connection 223 to the distribution destination determining unit 221. In addition, handing over means handling like a program argument. Specifically, the external transport layer receiving unit 222 delivers the packet data stored in the external connection 223 to the distribution destination determining unit 221.

  Here, the external connection 223 represents a connection state at the transport layer protocol level with the client device 40. The internal connection 225 represents a connection state at the transport layer protocol level with the processing server 30. For example, in the case of TCP (Transmission Control Protocol), the external transport layer receiving unit 222 and the transport layer transfer unit 224 manage connection state information, address / port information, and the like with the opposite system. On the other hand, the external transport layer receiving unit 222 and the transport layer transfer unit 224 are connectionless protocols in the case of UDP (User Datagram Protocol), and therefore do not manage connection state information with the opposite system.

  The distribution destination determination unit 221 has a function of delivering the packet data group of the external connection 223 to the key extraction unit 201 via the API 210 when acquiring the packet data group of the external connection 223 from the external transport layer reception unit 222. The distribution destination determination unit 221 receives the key information extracted from the key extraction unit 201 via the API 210, and transfers the transfer destination information 231 (for example, an ID in the consistent hash method) managed by the cluster configuration management unit 230. The internal connection 225 associated with the transfer destination processing server 30 is determined with reference to the space). That is, the distribution destination determination unit 221 has a function of associating the external connection 223 and the internal connection 225 (that is, correcting the destination address and port). Further, the distribution destination determination unit 221 has a function of delivering packet data from the existing external connection 223 that has already been associated to the internal connection 225.

  The transport layer transfer unit 224 has a function of controlling the internal connection 225 associated with the processing server 30 in the cluster. Further, the transport layer transfer unit 224 has a function of transmitting the packet data delivered to the internal connection 225 to the transfer destination processing server 30.

  The cluster configuration management unit 230 has a function of updating the transfer destination information 231 so as to correspond to the configuration after the increase / decrease (after change) when the increase / decrease occurs in the configuration of the processing server 30 in the cluster. The transfer destination information 231 stores the relationship between the conversion value obtained from the key information and the processing server 30 associated with the conversion value. As a specific example, in the case of the consistent hash method, the transfer destination information 231 corresponds to an ID space.

  Here, an example of the processing flow of the distribution server 20 will be described with reference to FIG. 3 (see FIG. 2 as appropriate). In FIG. 3, a portion indicated by a broken-line rectangle indicates a portion processed by the application unit 200.

  In step S301, the external transport layer receiving unit 222 receives a packet.

  In step S <b> 302, the external transport layer reception unit 222 determines whether the received packet is a packet for the existing external connection 223. For this determination, for example, information such as a destination address, a port number, and fragmentation included in the header of the packet is used. The packet data of the received packet is stored in the external connection 223 associated with the information included in the packet header. A new external connection 223 newly generated by the external transport layer receiving unit 222 is generated in step S306 described later, and is treated as an existing external connection 223 after generation.

  If it is determined that the packet is for the existing external connection 223 (Yes in step S302), the process proceeds to step S303. If it is determined that the packet is not for the existing external connection 223 (No in step S302), the process is as follows. Proceed to step S306.

In step S <b> 303, the distribution destination determination unit 221 determines whether the external connection 223 is already associated with the internal connection 225. The distribution destination determination unit 221 stores connection information 226 indicating information relating the external connection 223 and the internal connection 225 in a storage unit (not illustrated), and refers to the connection information 226 to determine in step S303. Execute.
If it is determined that it is associated with the internal connection 225 (Yes in step S303), the process proceeds to step S304. If it is determined that it is not associated with the internal connection 225 (No in step S303), the process proceeds to step S307. move on.

In step S <b> 304, the distribution destination determination unit 221 refers to the connection information 226 and delivers the packet data from the external connection 223 to the internal connection 225.
In step S <b> 305, the transport layer transfer unit 224 transmits the packet data transferred to the internal connection 225 to the transfer destination processing server 30 associated with the internal connection 225.

In step S306, the external transport layer receiving unit 222 newly creates an external connection 223.
In step S307, the external transport layer reception unit 222 stores the packet data group in a buffer (not shown) of the external connection 223.

In step S308, the key extraction unit 201 of the application unit 200 executes key information extraction processing.
Specifically, first, the external transport layer receiving unit 222 delivers the external connection 223 to the distribution destination determining unit 221. The distribution destination determination unit 221 acquires the external connection 223 and delivers the packet data group to the key extraction unit 201 of the application unit 200 via the API 210. At this time, the distribution server 20 defines an API 210 at the boundary between the application unit 200 in the application layer and the distribution processing unit 220 in the transport layer, and a packet data group is delivered by the API 210.

  Next, the key extraction unit 201 analyzes the received packet data group and executes a process of returning key information used for determining the transfer destination to the distribution destination determination unit 221 via the API 210. Note that if the received packet data does not include key information, the key extraction unit 201 returns null as a return value in order to receive subsequent packet data. In this key information extraction process, the application unit 200 (key extraction unit 201) in the application layer does not need to be aware of the cluster configuration or the like.

In step S309, the distribution destination determination unit 221 determines whether key information has been extracted. Specifically, the distribution destination determination unit 221 determines whether key information has been returned from the application unit 200 as a return value of the API 210. That is, the distribution destination determination unit 221 determines that the key information has been extracted when it is determined that the key information has been returned.
If it is determined that the key information has been extracted (Yes in step S309), the process proceeds to step S310. If it is determined that the key information has not been extracted (No in step S309), the process ends.

  In step S310, the distribution destination determination unit 221 refers to the transfer destination information 231 managed by the cluster configuration management unit 230, and the transfer destination processing server 30 associated with the conversion value obtained from the returned key information. ("Determine transfer destination" in FIG. 3). For example, when the consistent hash method is used, the distribution destination determination unit 221 refers to the ID space corresponding to the transfer destination information 231 and uses the hash value (corresponding to the converted value) of the returned key information. A corresponding transfer destination processing server 30 is determined.

  In step S311, the distribution destination determination unit 221 acquires the internal connection 225 associated with the transfer destination processing server 30, and executes association between the acquired internal connection 225 and the external connection 223. The associated relationship is stored in the connection information 226 by the distribution destination determination unit 221.

In step S312, the distribution destination determination unit 221 refers to the connection information 226 and delivers the packet data group from the buffer of the external connection 223 to the internal connection 225.
In step S <b> 313, the transport layer transfer unit 224 transmits the packet data group delivered to the internal connection 225 to the processing server 30.

  In the distribution server 20, since the transfer of the packet data between the external connection and the internal connection once associated is executed based on the connection information 226, the application unit 200 is not involved in subsequent packet processing. Absent. That is, the distribution server 20 executes only the extraction of key information necessary for determining the transfer destination in the application unit 200 of the application layer. The packet data transfer is executed as a transport layer transfer process (destination address or port correction) by the distribution destination determination unit 221.

  Therefore, the distribution server 20 of this embodiment does not cause processing overhead associated with application layer protocol processing, MTU excess associated with header addition, or the like, as compared with the case where all distribution processing is executed by the application unit 200 of the application layer. . Further, when response information is transmitted from the processing server 30 to the client device 40 when packet transmission by SIP is executed by UDP, there is no need to go through the distribution server 20, and the response time can be shortened. become.

Next, a function example of the processing server 30 will be described with reference to FIG.
The processing server 30 includes an application unit 300, a first API 310, a second API 311, a protocol processing unit 320, and a distributed data management unit 330.

  The application unit 300 has a function of executing processing at a level higher than the application layer, and includes a key extraction unit 301 and a signal processing unit 302. The key extraction unit 201 acquires a packet data group from the application driving unit 321 via the first API 310, extracts key information included in the packet data group, and sends the extracted key information to the application driving unit 321. Has a function to reply. The signal processing unit 302 has a function of acquiring a packet data group of the internal connection 323 via the application driving unit 321 and the second API 311 and executing signal processing using an application layer protocol.

The first API 310 has a function of delivering the internal connection 323 from the protocol processing unit 320 to the key extraction unit 301 and returning the key information extracted by the key extraction unit 301 as a return value. That is, the first AIP 310 has an input / output format similar to that of the API 210 (see FIG. 2).
The second API 311 has a function of delivering the internal connection 323 from the application driving unit 321 to the signal processing unit 302 and returning a signal processing result as response information.

  The protocol processing unit 320 includes an application driving unit 321 and an internal transport layer receiving unit 322. The application driving unit 321 has a function of delivering the packet data group stored in the buffer of the internal connection 323 to the key extracting unit 301 via the first API 310 and receiving key information as a return value. Further, the application driving unit 321 has a function of acquiring session data associated with the return key information from the data storage unit 331 and associating it with the internal connection 323. Then, the application driving unit 321 has a function of delivering the internal connection 323 and the session data to the signal processing unit 302 via the second API 311 and receiving response information.

  The internal transport layer receiving unit 322 has a function of receiving packet data transmitted from the distribution server 20 and determining whether the packet is a new connection 323. Next, when it is determined that the internal transport layer receiving unit 322 is new, the internal transport layer receiving unit 322 newly generates an internal connection 323. The internal transport layer receiving unit 322 has a function of storing the received packet data in a buffer (not shown) of the internal connection 323 and delivering the internal connection 323 to the application driving unit 321.

  The distributed data management unit 330 has a function of updating information in the data storage unit 331 in which session data associated with key information is stored. The data storage unit 331 stores session data indicating the session status, results during processing, the internal connection 323, and key information in association with each other. Note that data A and data B shown in FIG. 4 represent session data. Each data stored in the data storage unit 331 is associated with the internal connection 323 by the application driving unit 321.

  Here, a processing flow example of the processing server 30 will be described with reference to FIG. 5 (see FIG. 4 as appropriate). In FIG. 5, a portion indicated by a broken-line rectangle indicates a portion processed by the application unit 300.

  In step S <b> 501, the internal transport layer receiving unit 322 receives a packet from the distribution server 20.

In step S <b> 502, the internal transport layer receiving unit 322 determines whether the packet is for the existing internal connection 323.
If it is determined that the packet is for the existing internal connection 323 (Yes in step S502), the process proceeds to step S504. If it is determined that the packet is not for the existing internal connection 323 (No in step S502), the process is as follows. It progresses to step S503.

In step S503, the internal transport layer receiving unit 322 newly generates an internal connection 323.
In step S <b> 504, the internal transport layer receiving unit 322 stores the packet data group in a buffer (not shown) of the internal connection 323. Then, the internal transport layer receiving unit 322 delivers the internal connection 323 to the application driving unit 321.

In step S <b> 505, the application driving unit 321 refers to the data storage unit 331 managed by the distributed data management unit 330 and determines whether session data is associated with the internal connection 323.
If it is determined that session data is associated (Yes in step S505), the process proceeds to step S509. If it is determined that session data is not associated (No in step S505), the process proceeds to step S506.

  In step S506, the key extraction unit 301 executes key information extraction processing. Specifically, first, the application drive unit 321 delivers a packet data group to the key extraction unit 301 via the first API 310. When the key extraction unit 301 executes key information extraction processing and extracts key information, the key extraction unit 301 returns the key information as a return value to the application driving unit 321 via the first API 310.

In step S507, the application driving unit 321 determines whether key information has been extracted.
If it is determined that key information has been extracted (Yes in step S507), the process proceeds to step S508. If it is determined that key information has not been extracted (No in step S507), the process proceeds to step S510.

  In step S508, the application driving unit 321 refers to the data storage unit 331, acquires session data associated with the key information, and newly creates session data when there is no session data.

  In step S509, the application driving unit 321 delivers the internal connection 323 and the session data acquired in step S508 to the signal processing unit 302 via the second API 311.

  In step S <b> 510, the application driving unit 321 delivers the internal connection 323 to the signal processing unit 302 via the second API 311.

  In step S511, the signal processing unit 302 executes signal processing. Then, the signal processing unit 302 generates response information by signal processing.

  The internal connection 323 has a function of transmitting a response information packet to the opposite system (for example, the client device 40) (for example, a function of transmitting using a destination address, a port number, or the like). . The signal processing unit 302 of the application unit 300 in the application layer only needs to acquire the internal connection 323 and session data via the second API 311, execute signal processing, and deliver the result to the application driving unit 321. That is, the application unit 300 in the application layer does not need to be involved in transfer processing or the cluster structure. In the case of TCP, the response information is transmitted to the opposite system via the distribution server 20 along the path of the established connection. In the case of connectionless UDP, the response information bypasses the distribution server 20 and is transmitted to the opposite system via the load balancer 10. Therefore, in the case of UDP, the response time may be shortened.

  Here, a case where the function examples of the distribution server 20 and the processing server 30 are represented by a software structure will be described with reference to FIG. 6 (see FIGS. 2 and 4 as appropriate).

  FIG. 6A shows a case where the function example of the distribution server 20 shown in FIG. 2 is expressed by a software structure. The distribution server 20 includes an application layer protocol processing unit 600, an API 610, a transport layer protocol processing unit 620, and a cluster configuration management unit 630.

The application layer protocol processing unit 600 has the same function as the application unit 200 shown in FIG. 2, and executes key information extraction processing.
The API 610 has the same function as the API 210 shown in FIG. 2, transfers a packet data group from the transport layer protocol processing unit 620 to the application layer protocol processing unit 600, and transmits the key information extracted by the application layer protocol processing unit 600. Return to the port layer protocol processing unit 620.

The transport layer protocol processing unit 620 has the same function as the distribution processing unit 220 shown in FIG. 2, determines a transfer destination, and executes transport layer transfer processing (correction of destination address and port), The packet is transmitted to the transfer destination processing server 30.
The cluster configuration management unit 630 has the same function as the cluster configuration management unit 230 shown in FIG. 2, and when an increase / decrease occurs in the configuration of the processing server 30 in the cluster, the cluster configuration management unit 630 has a configuration after the increase / decrease (change) Correspondingly, the relationship between the conversion value obtained from the key information and the transfer destination processing server 30 associated with the conversion value is updated.

  By adopting such a configuration, the application layer protocol processing unit 600 is divided from the transport layer protocol processing unit 620 and the cluster configuration management unit 630 by the API 610, so only processing (key extraction processing) higher than the application layer is performed. Just do it. Therefore, the application layer protocol processing unit 600 can easily cope with various protocols (multi-protocols) as compared with the case where all the distribution processes of the distribution server 20 are executed by the application layer processes.

  Similarly, FIG. 6B shows a case where the function example of the processing server 30 shown in FIG. 4 is expressed by a software structure. The processing server 30 includes an application layer protocol processing unit 700, an API 710, a transport layer protocol processing unit 720, and a distributed data management unit 730.

The application layer protocol processing unit 700 has the same function as that of the application unit 300 shown in FIG. 4, and executes key information extraction processing and signal processing for generating response information.
The API 710 represents the same function as the first API 310 and the second API 311 shown in FIG. The API 710 delivers the packet data group and session data from the transport layer protocol processing unit 720 to the application layer protocol processing unit 700, and returns key information and response information to the transport layer protocol processing unit 720.

The transport layer protocol processing unit 720 has the same function as the protocol processing unit 320 shown in FIG. 4, and returns response information acquired from the application layer protocol processing unit 700 to the opposite system.
The distributed data management unit 730 has the same function as that of the distributed data management unit 330 shown in FIG. 4. Update the session data so that it corresponds.

  By adopting such a configuration, the application layer protocol processing unit 700 is divided into the transport layer protocol processing unit 720 and the distributed data management unit 730 by the API 710, and therefore processing higher than the application layer (key extraction processing and signal processing) ) Only need to be executed. Therefore, the application layer protocol processing unit 700 can easily deal with various protocols (multi-protocols) as compared with the case where all of the distribution processing of the distribution server 20 is executed by application layer processing.

Here, an example showing that the session data and the key information differ depending on the type of protocol handled by the network server system 800 will be described with reference to FIG.
As shown in FIG. 7, when the type of the network server system 800 is “SIP (proxy) server”, the session data is “SIP session state” and the key information is “value of Call-ID header”.
When the type of the network server system 800 is “SIP (B2BUA) server”, the session data is “B2BUA session state”, and the key information is “session ID set as a parameter in the Route header or Via header”. Here, B2BUA is an abbreviation for Back-To-Back User Agent.

When the type of the network server system 800 is “Web application server”, the session data is “HTTP session state”, and the key information is “session ID set in Cookie”. Here, HTTP is an abbreviation for Hypertext Transfer Protocol.
Further, when the type of the network server system 800 is “XCAP server”, the session data is “XML document” and the key information is “document selector set in the HTTP request line”. Here, XCAP and XML are abbreviations for XML Configuration Access Protocol and Extensible Markup Language, respectively.

  As shown in FIG. 7, when the type of the network server system 800 is different, the session data and the key information are also different. However, since the application layer protocol processing unit 600 (700) only needs to create software corresponding to only the key information (key information and response information), it can easily cope with multi-protocols.

  As described above, in the distribution server 20 of the scale-out type network server system 800 of the present embodiment, in the transport layer, first, the external transport layer receiving unit 222 receives a packet and stores the packet data. It is determined whether there is an external connection 223. Next, the distribution destination determination unit 221 refers to the connection information 226 that associates the external connection 223 and the internal connection 225, acquires the internal connection 225 associated with the existing external connection 223, and the existing external connection The packet data stored in the H.223 is transferred to the internal connection 225. Then, the transport layer transfer unit 224 transmits the packet data delivered to the internal connection 225 to the transfer destination processing server 30 associated with the internal connection 225.

In addition, the distribution server 20 analyzes a packet data group indicating a set of packet data, extracts a key information used for determining a transfer destination, a key extraction unit 201 in the application layer, and a conversion value and transfer obtained from the key information. Transfer destination information 231 associated with a previous processing server is provided. If the external transport layer receiving unit 222 determines that there is no existing external connection 223, the external transport layer receiving unit 222 newly generates an external connection 223 and stores the packet data of the received packet in the buffer of the generated external connection 223. . Next, the distribution destination determination unit 221 takes out the packet data group from the buffer, delivers the packet data group to the key extraction unit 201, acquires key information from the key extraction unit 201, and refers to the transfer destination information 231. The transfer destination processing server 30 associated with the conversion value obtained from the acquired key information is determined, and the generated external connection 223 and the internal connection 225 associated with the transfer destination processing server 30 are associated with each other. The packet data group of the buffer is delivered to the internal connection 225. Then, the transport layer transfer unit 224 transfers the packet data group to the transfer destination processing server 30.
Therefore, in the scale-out type network server system 800, it is possible to efficiently perform distributed processing and provide a signal processing technique that can easily cope with multi-protocols.

DESCRIPTION OF SYMBOLS 10 Load balancer 20 Distribution server 30 Processing server 40 Client apparatus 200 Application part 201 Key extraction part 210 API
220 distribution processing unit 221 distribution destination determination unit 222 external transport layer reception unit 223 external connection 224 transport layer transfer unit 225 internal connection 226 connection information 230 cluster configuration management unit 231 transfer destination information 300 application unit 301 key extraction unit 302 signal processing Part 310 First API
311 Second API
320 Protocol processing unit 321 Application driving unit 322 Internal transport layer receiving unit 323 Internal connection 330 Distributed data management unit 331 Data storage unit 600,700 Application layer protocol processing unit 610, 710 API
620, 720 Transport layer protocol processing unit 630 Cluster configuration management unit 730 Distributed data management unit 800 Network server system

Claims (4)

One or more distribution servers for determining a transfer destination processing server for the received packet, transmitting the packet to the transfer destination processing server, and a plurality of the processing servers for generating response information of the received packet and returning the response information The distribution server in a network server system having:
A storage unit for storing connection information in which an external connection and an internal connection are associated;
An external transport layer receiver of the transport layer that receives the packet and determines whether there is an existing external connection that stores the packet data;
When the external transport layer receiving unit determines that there is the existing external connection, the packet data stored in the existing external connection is associated with the existing external connection with reference to the connection information. A transport layer distribution destination determination unit that delivers to the internal connection,
A transport layer transport unit of a transport layer that transmits the packet data delivered to the internal connection to the transfer destination processing server associated with the internal connection;
A distribution server comprising: The distribution server analyzes a packet data group indicating the set of packet data and extracts key information used to determine a transfer destination, a key extraction unit of an application layer, and a conversion value obtained from the key information and the transfer A storage unit for storing transfer destination information associated with a previous processing server;
When the external transport layer receiving unit determines that there is no existing external connection, it newly generates an external connection, and stores the packet data of the received packet in the buffer of the generated external connection,
The distribution destination determination unit takes out a packet data group from the buffer, passes the packet data group to the key extraction unit, acquires the key information from the key extraction unit, refers to the transfer destination information, and A transfer destination processing server associated with the conversion value obtained from the acquired key information is determined, and the generated external connection is associated with the internal connection associated with the transfer destination processing server. Deliver the packet data group of the buffer,
The distribution server according to claim 1, wherein the transport layer transfer unit transfers the packet data group to the transfer destination processing server. One or more distribution servers for determining a transfer destination processing server for the received packet, transmitting the packet to the transfer destination processing server, and a plurality of the processing servers for generating response information of the received packet and returning the response information The distribution server in the network server system includes a storage unit that stores connection information in which an external connection and an internal connection are associated with each other.
In the distribution server,
An external transport layer reception procedure of the transport layer that receives the packet and determines whether there is an existing external connection that stores the packet data;
When it is determined in the external transport layer reception procedure that the existing external connection exists, the packet information stored in the existing external connection is associated with the existing external connection with reference to the connection information. The transport layer distribution destination decision procedure to be delivered to the internal connection,
A transport layer transfer procedure of a transport layer for transmitting the packet data delivered to the internal connection to the processing server of the transfer destination associated with the internal connection;
A program for running The distribution server analyzes a packet data group indicating the set of packet data and extracts key information used to determine a transfer destination, a key extraction unit of an application layer, and a conversion value obtained from the key information and the transfer A storage unit for storing transfer destination information associated with a previous processing server;
In the distribution server,
When it is determined in the external transport layer reception procedure that there is no existing external connection, a new external connection is generated, and the packet data of the received packet is stored in the generated external connection buffer.
In the distribution destination determination procedure, a packet data group is extracted from the buffer, the packet data group is transferred to the key extraction unit, the key information is acquired from the key extraction unit, and the transfer destination information is referred to, A transfer destination processing server associated with the conversion value obtained from the acquired key information is determined, and the generated external connection is associated with the internal connection associated with the transfer destination processing server. Deliver the packet data group of the buffer,
The program according to claim 3, for executing the transfer of the packet data group to the transfer destination processing server in the transport layer transfer procedure.

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