JP2015032865A - Network reception device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a network reception device on which a TCP/IP application performs reception processing freely as intended and data to be immediately processed is quickly processed without lowering as much as possible throughput that is an advantage of LRO reception processing.SOLUTION: A data section event for transferring data to an upper layer is instructed to a treatment layer in a neighborhood of a lower physical layer in advance from a TCP/IP application, and whether to send to an upper layer at a time of data reception is determined according to the data section event.

Description

  The present invention relates to a network receiving apparatus, and more particularly to an apparatus that enables efficient network signal reception.

  As an effort to improve TCP transmission / reception performance, network-related processing such as TCP packet processing originally processed by the CPU is performed on the NIC side by network interface card (NIC) hardware. For example, there are efforts such as LSO (Large Send Offload) in which LSI built-in LSI divides transmission data generated in the application layer into TCP segments, and LRO (Large Receive Offload) in which received TCP segments are reconstructed in reverse. To do.

  In particular, the LRO related to the reception processing reduces the CPU load (overhead) required for TCP stack processing by releasing the CPU from the TCP / IP stack processing that has been performed by the CPU so far by performing TCP segmentation processing. It is effective as a means for achieving the purpose of improving the throughput obtained.

  Further, for example, in Patent Document 1, an invention in which a router, an L3 switch, a NIC, or the like determines the size of a big packet based on the free capacity of a reception buffer and continues to reconstruct received packets until the size is satisfied. Is disclosed. By doing so, compared to the case where reconstruction is not performed, an amount corresponding to the header area can be saved, and efficient reception is possible in the case of data reception having a large size.

Patent Publication 2000-332817

However, performing LRO using a fixed size such as a buffer capacity in this way contributes to an improvement in throughput, but there is a problem that immediacy is lost. For example, when receiving print data, LRO works effectively because the print data body having a large data size places importance on throughput. However, when command data having a small data size is received together with the print data, the received data is sent to the upper layer in the segmentation unit when the LRO is received, so that the processing of this command may not be performed immediately. Even if the command is an instruction to cancel printing, the operation may be greatly delayed because it waits for the received data to be accumulated to a predetermined size. In this case, it will cause damage that cannot be ignored. End up. Note that Patent Document 1 describes a function of using an emergency flag and passing a packet to an upper layer as it is without accumulating the packet in which the flag exists, but this is a flag to be given on the transmission side to the last, There was a limit to the rapid processing on the receiving side.
In view of the above problems, the present invention improves network throughput, which is an advantage of LRO reception processing, and can perform received data processing in response to any request required by an upper layer, for example, a TCP / IP application. Providing equipment.

  The network receiver of the present invention is provided in the TCP / IP application layer, and includes a data delimitation instruction means for instructing a lower layer of a data delimiter event for sending received data to an upper layer, and a position lower than the transport layer. Data receiving means for referring to the data delimiter event instructed by the data delimiter instructing means and storing the received data without sending it to an upper layer until it is determined that the data delimiter event has occurred Means.

  Another network apparatus according to the present invention includes a data delimitation instruction unit provided in the TCP / IP application layer for instructing a data delimiter event for sending received data to an upper layer to a lower layer, and a layer lower than the transport layer. The data receiving means is located and does not send the received data to the upper layer until either (a) the data delimiter event occurs or (b) the data storage upper limit time is reached. Data receiving means for storing.

  The program of the present invention includes a data delimiter instruction means for instructing a data delimiter event for sending received data to an upper layer to a lower layer provided in a TCP / IP application layer, and a lower layer than a transport layer. The data receiving means that is located, refers to the data delimiter event instructed by the data delimiter instructing means, and stores the received data without sending it to the upper layer until it is determined that the data delimiter event has occurred It functions as a receiving means.

Another program according to the present invention includes a data delimiter instruction means for instructing a data delimiter event for sending a received data to an upper layer, which is provided in a TCP / IP application layer, to a lower layer, and a transport layer. Data receiving means located at a lower level, wherein the received data is transferred to an upper layer until either (a) the data delimiter event occurs or (b) the data storage upper limit time is reached. It functions as a data receiving means that accumulates without sending.

In the present invention, the data delimiter event is a criterion for determining that the data receiving means sends the received data to the upper layer, which is instructed by the TCP / IP application. In addition to a simple event, a plurality of events are combined with AND or OR. It is a concept that also includes the ones that have been programmed. The point is that the data receiving means can determine whether or not the event is established each time data is received.

  In the present invention, there is provided a mechanism for instructing in advance a determination rule for data delimitation (thus transferring data to the upper layer) from the upper application to the processing layer near the lower physical transmission. By this instruction, the reception process can be performed freely as the TCP / IP application intends. As a result, there is an effect that data that needs immediate processing can be processed promptly without reducing the throughput, which is an advantage of the LRO reception processing, as much as possible.

It is a block diagram of a network receiver. It is an operation | movement flow of a network receiver. It is an example of a session management table. This is the behavior of the data receiving means.

Embodiments according to the present invention will be described below with reference to the drawings.
[Example 1]
[Block Diagram]

  FIG. 1 is a block diagram of a network receiving apparatus 101 according to the present invention. This figure mainly shows the protocol stack of the network receiver 101. Note that the processing described below can be realized using either software or hardware.

  The TCP / IP application 102 is an application that uses the TCP / IP protocol, and FTP, HTTP, TELNET, and the like are generally famous. Incidentally, TCP / IP application 102 for use in the present invention may be of any type, including those prior protocols. In this embodiment, the TCP / IP application 102 includes data delimitation instruction means 103 for instructing a lower layer (TCP 112 described later) to delimit transfer of received data from a lower layer to an upper layer, and is desired by itself. Indicate data separation.

  The TCP 112 includes a table registration unit 104 and manages a session. The table registration unit 104 is a unit that registers session information used by the network reception device 101 as a session management table 105 in a storage area such as a RAM (not shown) provided in the network reception device 101. The session management table is specifically table information shown in FIG. 3, and a source IP address, a destination IP address, a source port number, and a destination port number are registered for each session. Thus, the data delimiter event designated by the data delimiter instructing means 103 in the TCP / IP application 102 is registered. The source IP address is the IP address on the transmitting device side, and the destination IP address is the IP address of the network receiving device 101 itself.

  The data delimiter event is a point of the present invention. An event desired by the TCP / IP application is instructed from the data delimiter instructing unit 103, and the TCP 112 that receives the event writes it to the session management table 105 for each session. . Although the event is arbitrary, in short, when the event occurs, the TCP 111 transfers received data stored in the buffer 107 described later to the TCP / IP layer. (Conversely, unless the event occurs, the data received in the lower layer is not transferred to the upper layer, and is stored in the buffer 107 as described later, regardless of the number of received packets. is there.)

Although the example of an event is given below, this invention is not limited to this.
(A) Receive data of a specific size (not only when the specific size data is received first, but also when a specific number of data is received a predetermined number of times)
(A) Receive a specific character ("CRLF", "\ x1B% -12345X" indicating a print break, or "\ x04" used as an EOF alternative code)
(C) Receiving the specified length by interpreting the length information (the first 4 bytes of the received data are interpreted as the length N of the subsequent data, and a data delimiter event is established by receiving 4 + N bytes of data)
(D) Receive TCP specific flag ("OOB", "FIN", etc.)

The data delimiter event may be a logical combination of a plurality of events by AND or OR.

Further, it may be a macro program as a subtask in a data reception task executed at a specific port number. As examples (1) and (2), the macro program algorithm related to two TCP ports is illustrated below.

Example (1) TCP port NO. 80 for mode a
Receive HTTP HEADER until two consecutive CRLFs
If there is a CONTENT LENGTH item, set to LEN and enter mode b mode b
The specified size or the specified size received every 16 Kbytes is subtracted for each reception, and when it becomes zero, the mode shifts to mode a.
Ignore PUSH. FIN is a macro program that consists of two modes of termination. In mode a, data is sent to the upper layer in the event of receiving two consecutive CRLFs, and in mode b, every 16K bytes are received or the specified size is received. Send data to upper layer upon expiration.

Example (2) TCP port NO. In case of 515, mode a
Mode b in which the LPD command is received until 02 or 03 is received until LF is received.
The specified size or the specified size that is received every 16 Kbytes is subtracted for each reception, and when it becomes zero, the mode shifts to mode a.
Ignore PUSH. FIN is a macro program consisting of two modes, ending. In mode a, data is sent to the upper layer at the event that LF is received. Send data to.
By determining whether or not the received data is to be sent to an upper layer with such a macro program, it is possible to send the received data in response to a strict request required by the TCP / IP application.

  Returning to FIG. 1, the network I / F 108, the LAN controller driver 109, the data link 110, and the IP 111 are the same as those in a general network device, and a description thereof will be omitted. As shown in FIG. 1, the received data sequentially proceeds upward through the protocol stack through the network I / F 108 and is finally sent to the TCP / IP application 102.

The data receiving unit 106 is a unit located between the LAN controller driver 109 and the data link 110. In the present invention, since the data receiving means 106 is an engine part that executes a so-called LRO process, the data receiving means 106 is located immediately below the data link 110 on the protocol stack. It should be noted that the hierarchy in which the data receiving means 106 is located is not limited to the above, but may be at least lower than the transport layer (TCP 112 in the figure).
This is because the present invention manages received data using session information used by the TCP 112.

  The data receiving means 106 is means for determining whether or not the received data sent from the LAN controller driver 109 is sent to the data link 110 which is an upper layer. Specifically, when data is received, the session management table 105 is referenced to determine whether or not a predetermined event instructed by the TCP / IP application has occurred for the session. If it is determined that the instructed event has not occurred, the data just received is stored in the buffer 107. On the other hand, if the instructed event has occurred, the received data stored in the buffer 107 is read out, combined with the received data, and sent to the data link 110.

  In the session management table shown in FIG. 3, a data delimiter event column is described from an event code and an event parameter. The event code indicates the type of event described above, and the event parameter is a parameter in the event. For example, the event code “1” is the data size, “2” is the character, “3” is the TCP specific flag, and so on. In session number 1 in FIG. 3, the data delimiter event is 1-32000, indicating that it is an event that receives 32000 bytes of data. In session number 2, 2-CRLF is a CRLF character received. It means that it is an event. In session number 1 in which the data size desired by the TCP / IP application is 32000 bytes, storage in the buffer 107 is repeated until the received data reaches 32000 bytes, and the desired data is accumulated and sent to the data link 110. On the other hand, in session number 2, the received data is stored in the buffer 107 until the CRLF code is received regardless of the data size, and when the CRLF character is received, the received data stored in the buffer is sent to the data link 110. .

Furthermore, when a macro program as described above is used, P as an event code and the name of a program to be executed as an event parameter are recorded in the data delimiter event column of the session management table.
[flow]

  FIG. 2 is an operation flow of the network receiving apparatus 101. As shown in FIG. 2, the network receiving apparatus 101 includes two tasks, a table registration task and a data reception task. Each task is executed by each means described above. Specifically, the table registration task is executed by the table registration means 104, and the data reception task is executed by the data reception means.

  First, the table registration task will be described. In step 201, it is determined whether a data reception request has occurred in the TCP / IP application 102. If it has not occurred, the determination continues until it occurs, and if it has occurred, the process proceeds to step 202. In step 202, an instruction (data delimiter event) regarding data delimiter included in the generated data reception request is recognized. In step 203, the session in which the reception request has occurred is authorized. Specifically, a source IP address, a destination IP address, a source port number, and a destination port number. In step 204, the session information and the data delimiter event are registered as a set in the session management table 105.

Next, the data reception task will be described. In step 251, it is determined whether or not there is data reception. If no data is received, detection of data reception is continued, and if it is received, the process proceeds to step 252. In step 252, the received data session is authorized. This is information such as the source IP address as described above. In step 253, the size of the received data is certified. (Of course, step 253 can be omitted if there is no element specifying the size in the indicated data break event). In step 254, the session management table 105 is referred to and it is determined whether or not a data break event for the corresponding session has occurred. If no event has occurred, the received data is stored in the buffer 107 in step 255. On the other hand, if a data delimiter event has occurred in step 254, the received data is sent to the upper layer, in this embodiment, the data link 110. Of course, if there is received data stored in the buffer 107, it is read out, combined with the received data, and sent. Although not shown, the session information registered in the table at this time may be deleted.
[Other Embodiments]

  In the previous embodiment, the table registration unit 104 exists in the TCP 112, but may exist on the TCP / IP application 102 side. In this case, the table registration unit 104 may be incorporated into the normal TCP / IP application 102.

  Even if a data break event registered in the table has not occurred, if a certain period of time (data storage upper limit time) has elapsed since the start of data reception in the session, the received data is forcibly sent to the upper layer. You may do it. This is to prevent a situation in which the data delimiter event generation condition is delayed such that data is lost in the middle of the communication path and the received data is not transferred to the upper layer indefinitely. The data storage upper limit time is a parameter set by the user in the initial setting. FIG. 4 is a table showing whether or not the data receiving means 106 sends the received data to the upper layer in each case of “data delimiter event occurrence” and “data storage upper limit time coming”. As can be seen from the figure, if at least one of “data separation event instructed by TCP / IP application occurs when data is received” or “data storage upper limit time is reached” is satisfied, the received data is transferred to the upper layer. Send to.

Furthermore, in the previous embodiment, an example was given in which a data delimiter event was defined for each session and managed by the session management table. However, the TCP / IP application previously defined a different event for each port number to the lower layer and indicated it. It is also possible to keep it. Thereby, management for every session can be omitted.
[Summary]

  In the present invention, a table for holding a data delimiter condition requested by the TCP / IP application is provided for each session or port, and the data receiving means sends received data to an upper layer based on the condition registered in the table . As a result, the throughput, which is an advantage of the LRO reception process, is improved, and the reception process can be performed freely according to the conditions required by the TCP / IP application.

103 Data delimitation instruction means 104 Table registration means 105 Session management table 106 Data reception means 107 Buffer

Claims (4)

A data delimiter instructing means for instructing a lower layer a data delimiter event for sending received data to an upper layer, provided in the TCP / IP application layer;
Data receiving means positioned lower than the transport layer, referring to the data delimiter event instructed by the data delimiter instructing means, and receiving the received data until it is determined that the data delimiter event has occurred Data receiving means for storing without sending to the layer;
A network receiver comprising:
A data delimiter instructing means for instructing a lower layer a data delimiter event for sending received data to an upper layer, provided in the TCP / IP application layer;
Data receiving means located below the transport layer, received until either (a) the data delimiter event occurs or (b) the data storage upper limit time is reached Data receiving means for storing data without sending it to the upper layer;
A network receiver comprising:
Computer
A data delimiter instructing means for instructing a lower layer a data delimiter event for sending received data to an upper layer, provided in the TCP / IP application layer;
Data receiving means positioned lower than the transport layer, referring to the data delimiter event instructed by the data delimiter instructing means, and receiving the received data until it is determined that the data delimiter event has occurred Data receiving means for storing without sending to the layer;
A program characterized by making it function.
Computer
A data delimiter instructing means for instructing a lower layer a data delimiter event for sending received data to an upper layer, provided in the TCP / IP application layer;
Data receiving means located below the transport layer, received until either (a) the data delimiter event occurs or (b) the data storage upper limit time is reached Data receiving means for storing data without sending it to the upper layer;
A program characterized by making it function.