JP2653187B2 - Hierarchical protocol processing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a processing system of a layered protocol in a communication control system.

(Prior Art) With an increase in communication speed, a service for transferring a large amount of data such as high-definition image information is emerging. The response time is required to be as short as possible due to psychological factors of service users. For this purpose, the processing speed of the communication control device needs to be increased.

Therefore, when communication is divided into several phases, it can be divided into a connection setting / release phase of each layer (hereinafter referred to as a layer) and a data transfer phase after the connection is set. Among them, the data transfer phase has a high time ratio when viewed from the whole communication.

Therefore, in order to reduce the response time, it is most important to process this data transfer phase at high speed. In general, the connection setup / release phase requires complicated processing. However, in the data transfer phase, each layer deletes a fixed protocol header (hereinafter, header) from data at the time of data reception, and each layer transmits data at the time of data transmission. In many cases, only processing for adding a fixed header to data is required.

In the conventional layered protocol processing method, first, from the viewpoint of program distribution and ease of change, protocol processing is provided for each layer, and from this protocol processing unit, from setting of connection of that layer to data transfer, release of connection And data is transferred to an adjacent layer by performing inter-task communication. Conversely, from the viewpoint of speeding up, processing is not described by task management, but described by program logic.

(Problems to be Solved by the Invention) However, in the above-described conventional method, when a protocol processing unit is provided for each layer, all data is taken over and processed by inter-task communication between the layers. There is a disadvantage that it takes a lot of time to be processed by the layer.

On the other hand, when the processing is described by the program logic, there are disadvantages that the circulation of the program is reduced and the range of the change of the protocol specification to the program is large.

An object of the present invention is to eliminate these drawbacks, and an object of the present invention is to provide a layered protocol processing method for speeding up data transfer processing.

(Means for Solving the Problems) In order to solve the above-mentioned drawbacks, the present invention provides a communication control method for processing a layered protocol, in which a connection control unit of each layer is bypassed and a protocol header of a plurality of layers is added. The present invention is characterized in that a bypass control unit that collectively adds or deletes information and determines whether the information is data transfer information or information other than data transfer is provided.

(Operation) According to the present invention having the above-described configuration, by performing the protocol processing of the data transfer phase after the connection of the highest layer is set by the bypass control unit among the plurality of combined layers, Then, headers of a plurality of layers are collectively added or deleted, and if there is abnormal data, the abnormal data is passed to the connection control unit for processing. That is, if the data transfer processing from layer N to layer N + n is handled collectively, in this case, the connection is connected by the connection control unit of each layer. The subsequent data transfer process is performed only by the bypass control unit that handles the transfer process collectively. When data is transferred from the upper layer N + n to the bypass controller, the bypass controller first checks the state from layer N to layer N + n. As a result of the status check, in the case of the data transfer phase, the bypass control unit collectively adds headers from layer N to layer N + n, and takes over to the lower layer of layer N.
As a result of status check, if it is not the data transfer phase,
The connection control unit of layer N + n takes over. When the data is transferred from the lower layer to the bypass control unit, the bypass control unit first executes the layer N to the layer N
Check the status up to + n. As a result of the status check, in the data transfer phase, the bypass control unit analyzes the headers from the layer N to the layer N + n collectively, and deletes the headers in the case of data higher than the layer N + n collectively. Take over to the upper layer of layer N + n.
If the analysis result is not higher-level data of layer N + n, the data is taken over to the connection control unit of layer N. Also,
As a result of status check, if it is not the data transfer phase,
The data is passed to the layer N connection control unit.

Therefore, the present invention can solve the above-mentioned drawbacks, and can provide a hierarchical protocol processing method for speeding up data transfer processing.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a functional block diagram showing an embodiment of the present invention. In this embodiment, connection control units 1 to 3 from layer N to layer N + n are surrounded by a bypass control unit 4, and data is transferred to these layers via the bypass control unit 4. It is.

 Next, the operation of the present embodiment will be described.

When the state from the layer N to the layer N + n is in the data transfer phase, and when a data transfer instruction is received from the upper layer, the bypass control unit 4 switches the layer N to the layer N + n
The headers up to and including the header are collectively added and the data is transferred to the lower layer. When the data reception report is received from the lower order, the headers from the layer N to the layer N + n are checked. As a result, if the data is higher than the layer N + n,
The header is collectively deleted, and the data is transferred to the upper layer of the layer N + n.

When an instruction other than the data transmission instruction is received from the host,
When a report other than the data reception report is received from the lower layer, or when a data reception report is received, but is not the upper layer data of the layer N + n (including the case of illegal data)
Means that the bypass control unit 4 is the layer N connection control unit 1
Alternatively, the data is transferred to the layer N + n connection control unit 3.

The above operation is further performed on layer N to layer N shown in FIG.
Description will be made below based on n + 1 layers up to + n and the relationship between upper and lower protocol headers and data of these layers.

When data is passed from the upper layer N + n to the bypass control unit, the bypass control unit first checks the state from layer N to layer N + n. As a result of the status check, in the case of the data transfer phase, the bypass control unit gives the headers 22 to 24 from the layer N to the layer N + n collectively, and takes over the lower order of the layer N. As a result of the status check, if the phase is not the data transfer phase, the layer N + n
Is passed to the connection control unit. When data is transferred from the lower layer to the bypass control unit, the bypass control unit first checks the state from layer N to layer N + n. As a result of the status check, in the data transfer phase, the bypass control unit analyzes the headers from the layer N to the layer N + n collectively, and deletes the headers in the case of data higher than the layer N + n collectively. Take over to layer N + n. If the analysis result is not higher-level data of layer N + n, the data is taken over to the connection control unit of layer N. If the result of the status check indicates that the data transfer phase is not the data transfer phase, the data is taken over to the connection control unit of layer N.

FIG. 3 shows an example in which N = 4 and n = 1 in FIG. 1. CCITT Recommendation X.224 is used as a layer 4 protocol.
Class O (CCITT Recommendation T.70) C as Layer 5 protocol
This is the processing flow when CITT recommendation X.225 kernel + full duplex is selected. FIG. 3 shows a flow of processing when the network connection is completed, the transport connection is established, the session connection is established, data is transmitted and received, and then the session connection is disconnected. In FIG. 3, CN (CONNECT), AC (A
CCEPT), DT (DATA TRANSFER), FN (FINISH), DN (DI
SCONNECT) is the name of the session layer protocol data unit.
(Transport layer) is transferred as a data block (the data block name of the transport layer is in accordance with T.70 in order to distinguish it from the data block name of the session layer). Among them, DT is a data unit higher than layer 5 (in this case, a presentation or application layer). Less than,
With reference to FIG. 3, the flow of processing in a normal state will be described.

First, TC, which is a transport layer open request
R (transport connection request) is passed to the bypass control unit 33. The bypass control unit 33 first checks that the transport layer and the session layer are in the data transfer phase. In this case, since it is not the data transfer phase, the TCR is taken over by the layer 4 control unit 31 which is the connection control unit of the transport layer. The layer 4 control unit 31 knows that it is a TCR by the header analysis, and determines the layer 5 control unit which is a connection control unit of the session layer.
Make an open request to 32. That is, the upper layer inquires whether the transport layer can be opened. Upon receiving the open request, the layer 5 control unit 32 returns an open response to the layer 4 control unit 31. Upon receiving the open response, the layer 4 control unit 31 receives a TCA (transport connection confirmation).
And instructs transmission via the data transfer processing unit 33.

Next, the bypass control unit 33 receives a CN that is a session layer open request (this is called a logon request). The bypass control unit 33 checks the state in the same manner as when the TCR is received, and then takes over to the layer 4 control unit 31. The layer 4 control unit 31 knows that the TDT has been received by the header analysis, deletes the transport layer header, and reports the data reception to the layer 5 control unit 32. Then, the layer 5 control unit 32 knows from the header analysis that the received data is the CN, and inquires via the bypass control unit 33 whether or not the upper level can accept the logon request. As a result, a logon response is received from the host. Layer 5 control unit
32 receives the logon response via the bypass control unit 33,
The AC is edited, and a data transmission instruction is issued via the layer 4 control unit 31 (adding a transport layer header to the AC) and the bypass control unit 33. As a result, the session layer is opened and a data transfer phase is started.

Thereafter, upon receiving the DT, the bypass control unit 33 first checks the state. As a result of the check, since it is the data transfer phase, the header analysis of the received data is performed, and it is known that the received data is DT. After collectively deleting the transport layer header and the session layer header of the DT, the bypass control unit 33 passes the data directly to the upper layer, and the layer 4 control unit 31 and the layer 5 control unit 32 do not take over the data. .

Next, when a data transmission instruction is received from the upper layer, the bypass controller 33 checks the state and delivers the data directly to the lower layer (when assembling or dividing is necessary in the transport layer, the bypass controller 33 also assembly/
Perform a split).

Thereafter, upon receiving the FN, the bypass control unit 33 performs a header check on the received data after checking the status. In this case, since it is not DT but FN, a data reception report is sent to the layer 4 control unit 31 (the bypass control unit 33 does not know that the received data is FN. Just know). The layer 4 control unit 31 analyzes the header, deletes the transport layer header, and then takes over to the layer 5 control unit 32. As a result of the header analysis, the layer 5 control unit 32 knows that the FN has been received, and raises a logoff request via the bypass control unit in order to inquire of a higher order whether logoff is allowed. At this point, the state exits the data transfer phase. When the bypass control unit 33 receives the logoff response from the host, the state is not the data transfer phase, and thus the bypass control unit 33 delivers the logoff response to the layer 5 control unit 32.
The layer 5 control unit 32 edits the DN, and
(Add a transport layer header to the DN) and instruct data transmission via the bypass control unit 33.

When control is passed from the bypass control unit 33 to the layer 4 control unit 31 or the layer 5 control unit 32, it is necessary to prevent the subsequent data from being processed in advance in order to prevent reversal of the process. A simple way to achieve this is to receive illegal data in the data transfer phase, or to receive data other than DT, to escape from the data transfer phase. When the control is passed to the 4 control unit 31 or the layer 5 control unit 32, all data to be received and data to be transmitted thereafter can be transmitted through the layer 4 control unit 31 or the layer 5 control unit 32. Alternatively, the bypass control
You can also meet at 33.

FIG. 4 is a functional block diagram showing another embodiment according to the present invention. Unlike FIG. 1, in this embodiment, the connection control units 41 to 43 from layer N to layer N + n are not surrounded by the bypass control unit 44, and are connected to the bypass control unit after the connection to layer N + n is established. This is an embodiment in which control is transferred. In this case, the layer N
And the upper layer N + n need to determine which of the bypass control unit 44, the layer N connection control unit 41, and the layer N + n connection control unit 43 should pass control depending on whether the state is the data transfer phase or not. There is.

(Effects of the Invention) As described above, according to the present invention, the inter-layer interface is not realized only by the inter-task communication, but the data transfer phases of a plurality of layers are collectively provided by providing one bypass control unit. Therefore, the speed of the data transfer process can be increased. In addition, for a plurality of connection controls, a connection control unit is provided for each layer in addition to the bypass control unit, and control is performed by inter-task communication. Therefore, it is possible to minimize a decrease in program distribution and ease of change. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a hierarchical protocol processing system according to an embodiment of the present invention, FIG. 2 is a diagram showing the relationship between headers and data between a plurality of layers, and FIG. 3 is a specific example of FIG. FIG. 4 is a block diagram showing the configuration of a hierarchical protocol processing system according to another embodiment of the present invention. 1,41: connection control unit of layer N, 2,42: connection control unit of layer N + 1, 3,43: connection control unit of layer N + n, 4,33,44: bypass control unit, 21: upper layer of layer N + n Data, 22: header and data of layer N + n, 23: header and data of layer N + 1, 24: header and data of layer N, 25: header and data when handling from layer N to layer N + n collectively, 26: Layer N lower header and data, 31: Layer 4 control unit, 32: Layer 5 control unit.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shigehiko Matsushita Nippon Telegraph and Telephone Corporation, 1-6-1, Uchisaiwaicho, Chiyoda-ku, Tokyo (56) References JP-A-1-162962 (JP, A) JP-A Sho 64-32360 (JP, A)

Claims (1)

(57) [Claims] In a communication control method for processing a layered protocol, a connection control unit of each layer is bypassed, a protocol header of a plurality of layers is collectively added or deleted, and the information is information of data transfer. Or a bypass control unit for determining whether the information is other than the data transfer. When the information of the data transfer is given, the protocol processing of the data transfer is performed by the bypass control unit, and the information other than the data transfer is given. When the connection control unit receives the information, the information is passed to the connection control unit for processing.