JPH0646734B2 - Data protection method for broadcast transmission system - Google Patents
Data protection method for broadcast transmission systemInfo
- Publication number
- JPH0646734B2 JPH0646734B2 JP62178243A JP17824387A JPH0646734B2 JP H0646734 B2 JPH0646734 B2 JP H0646734B2 JP 62178243 A JP62178243 A JP 62178243A JP 17824387 A JP17824387 A JP 17824387A JP H0646734 B2 JPH0646734 B2 JP H0646734B2
- Authority
- JP
- Japan
- Prior art keywords
- station
- transmission
- stations
- data
- buffer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Description
本発明は複数の局からなり、この各局は各局別の送信デ
ータ格納領域（局別送受信バッファ）を持つ送受信バッ
ファを備え、各局は自局の送受信バッファ内における自
局の送信データ格納領域（局別送信バッファ）内の送信
データを他の全局に送信するブロードキャスト伝送シス
テムにおいて、 特に送受信データの破壊を防ぐためのデータ保護方法に
関する。 なお以下各図において同一の符号は同一もしくは相当部
分を示す。The present invention comprises a plurality of stations, each station is provided with a transmission / reception buffer having a transmission data storage area for each station (transmission / reception buffer for each station), and each station has its own transmission data storage area (station In a broadcast transmission system for transmitting transmission data in another transmission buffer) to all other stations, the present invention particularly relates to a data protection method for preventing transmission / reception data from being destroyed. In the drawings below, the same reference numerals indicate the same or corresponding parts.
第３図はこの種のブロードキャスト伝送における各局の
送受信バッファ間の送受信データの流れの詳細説明図で
ある。同図においてＴ（Ｔ１〜Ｔｎ）は相互にブロード
キャスト伝送を行う局、Ｌは各局Ｔに共通のデータ伝送
路となるリンク、Ｂ（Ｂ１〜Ｂｎ）はそれぞれ局Ｔ１〜
Ｔｎ内の送受信バッファで、この伝送における送受信デ
ータが一時格納されるバッファメモリである。 各送受信バッファＢはそれぞれ局Ｔ１〜Ｔｎに対応して
所定のアグレス領域づつに分割された送信または受信デ
ータ領域としてのｎ個の局別送受信バッファｂからな
る。即ち送受信バッファＢ１は局別送受信バッファｂ
（ｂ11〜ｂ1n）からなり、同じく送受信バッファＢ２は
局別送受信バッファｂ（ｂ21〜ｂ2n）からなり、以下同
様に送受信バッファＢｎは局別送受信バッファｂ（ｎ１
〜ｂｎ）からなる。 ここで局別送受信バッファｂのうち斜線を附したｂ11，
ｂ22，ｂ33〜ｂnnはそれぞれ局Ｔ１，Ｔ２，Ｔ３〜Ｔｎ
の送信データが格納される領域であり、特にこの領域を
区別するときは局別送信バッファと呼ぶ。また局別送受
信バッファｂのうち前記の局別送信バッファｂ11，ｂ22
〜ｂnnを除いた局別送受信バッファはそれぞれ、その属
する局（当該局）以外の局から当該局へ送信された送信
データ（つまり当該局にとっての受信データ）が格納さ
れる領域で、特にこの領域を区別するときは局別受信バ
ッファという。 ブロードキャスト伝送の場合、第３図の例では、局Ｔ１
から送信される局別送信バッファｂ11内の送信データは
リンクＬを介してそれぞれ局Ｔ２〜Ｔｎに受信されて、
この各局内の局別受信バッファｂ21〜ｂn1に格納され
る。同様に局Ｔ２から送信される局別送信バッファｂ22
内の送信データはそれぞれ局Ｔ１およびＴ３〜Ｔｎに受
信されてこの各局内の局別受信バッファｂ12およびｂ32
〜ｂn2に格納され、また局Ｔｎから送信される局別送信
バッファｂnn内の送信データはそれぞれＴ１〜Ｔn-1
（ただしＴn-1は図外）に受信されてこの各局内の局別
受信バッファｂ1n〜ｂn-1，ｎ（ただしｂn-1，ｎは図
外）に格納される。FIG. 3 is a detailed explanatory diagram of the flow of transmission / reception data between the transmission / reception buffers of each station in this type of broadcast transmission. In the figure, T (T1 to Tn) are stations that perform mutual broadcast transmission, L is a link that serves as a data transmission line common to each station T, and B (B1 to Bn) is each of the stations T1 to T1.
A transmission / reception buffer in Tn is a buffer memory in which transmission / reception data in this transmission is temporarily stored. Each transmission / reception buffer B comprises n station-specific transmission / reception buffers b as transmission or reception data areas divided into predetermined aggress areas corresponding to the stations T1 to Tn. That is, the transmission / reception buffer B1 is the transmission / reception buffer b for each station.
(B11 to b1n), the transmission / reception buffer B2 also includes station-specific transmission / reception buffer b (b21-b2n), and similarly, the transmission / reception buffer Bn includes station-based transmission / reception buffer b (n1).
~ Bn). Here, the transmission / reception buffer b for each station b11 with diagonal lines,
b22, b33 to bnn are stations T1, T2, T3 to Tn, respectively.
Is an area in which the transmission data is stored, and is referred to as a station-specific transmission buffer particularly when this area is distinguished. The station-specific transmission / reception buffer b includes the station-specific transmission buffers b11 and b22.
Each station-specific transmission / reception buffer excluding ~ bnn is an area for storing transmission data (that is, reception data for the station) transmitted from the station other than the station to which the station belongs (the station concerned), in particular, this area. When distinguishing, it is called a reception buffer for each station. In the case of broadcast transmission, in the example of FIG.
The transmission data in the transmission buffer b11 for each station transmitted from the station is received by the stations T2 to Tn via the link L,
It is stored in the reception buffers b21 to bn1 for each station in each station. Similarly, the transmission buffer b22 for each station transmitted from the station T2
The transmission data in the stations are received by the stations T1 and T3 to Tn, respectively, and the station-specific reception buffers b12 and b32 in the stations are received.
To bn2, and the transmission data in the station-specific transmission buffer bnn transmitted from the station Tn are T1 to Tn-1 respectively.
(However, Tn-1 is not shown in the figure) and is stored in the station-specific reception buffers b1n to bn-1, n (however, bn-1, n are not shown) in each station.
第４図は前記の局別送信バッファのアドレス領域に重複
がある場合のデータ授受の説明図である。同図において
Ｔi-1，Ｔｉ，Ｔｊは局、Ｂi-1，Ｂｉ，Ｂｊはそれぞれ
この各局に属する送受信バッファ、ｂ（i-1）ｉは局Ｔi
-1内の局別受信バッファ、ｂii，ｂjjはそれぞれ局Ｔ
ｉ，Ｔｊ内の局別送信バッファである。この例ではバッ
ファｂiiとｂjjとの間に斜線部のような重複領域がある
ものとする。 この場合、局Ｔi-1内の局別受信バッファｂ（b-1）ｉに
は局Ｔｉの局別送信バッファｂii内の送信データのほか
に、局Ｔｊの局別送信バッファｂjj内の斜線部の送信デ
ータが交叉斜線部のように混入することになる。従って
例えば局Ｔi-1が局Ｔｉからの受信データを使って演算
しているときにこの演算データが局Ｔｊからの受信デー
タによって破壊され演算結果が異常になってしまうこと
になる。 従って各局の送受信バッファＢ内を分割してブロードキ
ャスト伝送を行うシステムにおいては、バッファＢ内の
局別送信バッファ領域が他の局の同領域と重複しないよ
うにする必要がある。 従来、このような重複を防ぐ方法としてはシステム設計
時に重複しないように送受信バッファＢを分割し、それ
を各々の局に対して設定する方法と、ブロードキャスト
される送信データにそのデータの送信局の送信データ領
域情報を附け、その情報によって領域重複のチェックを
行う方法とがあった。 しかしながら前者の方法では、誤って設定してしまうと
いう問題点が残り、後者の方法では前記のように誤って
設定が行われた場合、前記のように受信データ自体が破
壊されてチェックができなくなるという問題点が残る。 本発明の目的は互いにブロードキャスト伝送を行う各局
の局別送信バッファ領域が重複しているかどうかを、各
局の伝送への参加前にチェックし、重複していれば伝送
への参加をさせなくするデータ保護方法を提供すること
により、局別送信バッファ領域の重複の有無を確実に監
視すると共に、すでに稼動しているシステムに対して
も、間違った送受信データを使用させないようにするこ
とを目的とする。FIG. 4 is an explanatory diagram of data transmission / reception when the address areas of the station-specific transmission buffers are overlapped. In the figure, Ti-1, Ti, Tj are stations, Bi-1, Bi, Bj are transmission / reception buffers belonging to the respective stations, and b (i-1) i is station Ti.
-1 receive buffer for each station, bii and bjj are station T respectively
It is a transmission buffer for each station in i and Tj. In this example, it is assumed that there is an overlapping area such as a shaded area between the buffers bii and bjj. In this case, in addition to the transmission data in the station-specific transmission buffer bii of the station Ti, the shaded area in the station-specific transmission buffer bjj of the station Tj is stored in the station-specific reception buffer b (b-1) i in the station Ti-1. The transmission data of 1 will be mixed in like the cross-hatched portion. Therefore, for example, when the station Ti-1 is operating using the received data from the station Ti, the calculated data is destroyed by the received data from the station Tj and the operation result becomes abnormal. Therefore, in a system in which the transmission / reception buffer B of each station is divided to perform broadcast transmission, it is necessary to prevent the station-specific transmission buffer area in the buffer B from overlapping the same area of other stations. Conventionally, as a method of preventing such duplication, a method of dividing the transmission / reception buffer B so that it does not overlap at the time of system design and setting it for each station, and a method of transmitting the broadcast data to the transmission station of the data There was a method of adding transmission data area information and checking the area overlap based on that information. However, the former method has a problem that it is erroneously set. When the latter method is erroneously set as described above, the received data itself is destroyed as described above and the check cannot be performed. The problem remains. The object of the present invention is to check whether or not the station-specific transmission buffer areas of the stations that perform broadcast transmission overlap with each other before participating in the transmission of each station. By providing a protection method, it is possible to reliably monitor the duplication of the transmission buffer area for each station and prevent the already operating system from using the wrong transmission and reception data. .
前記の目的を達成するために本発明の方法は、『複数の
局（Ｔ１〜Ｔｎなど）からなり、 前記の各局は、自局を含む各局ごとの送信データを一時
記憶する送受信バッファであって、前記の局ごとに予め
定められたアドレスの個別記憶領域（局別送受信バッフ
ァｂなど）を持つ送受信バッファ（Ｂなど）を備え、 前記の各局は自局の前記送受信バッファ内における自局
に対応する前記個別記憶領域（以下局別送信バッファと
いう）内の送信データを他の各局へ送信し、該他の各局
は該送信データを自局の前記送受信バッファ内における
この送信データの送信局に対応する前記個別記憶領域へ
一時格納するブロードキャスト伝送のシステムにおい
て、 前記のブロードキャスト伝送を開始するに先立って、前
記の局の１つ（Ｔｉなど）をマスタ局とし、 該マスタ局は自局を除く他の各局から、少なくとも当該
局の前記局別送信バッファについてのアドレスデータを
受信して、前記局別送信バッファの領域間に重複がある
か否かを調べ、この重複が無いことが確認された局（以
下伝送参加可能局という）の各々へ、該伝送参加可能局
の全てについての局番データを送信し、 以後、前記伝送参加可能局間で前記のブロードキャスト
伝送を行わせるように』するものとする。In order to achieve the above-mentioned object, the method of the present invention is “consisting of a plurality of stations (T1 to Tn, etc., each station is a transmission / reception buffer for temporarily storing transmission data of each station including its own station, , A transmission / reception buffer (B, etc.) having an individual storage area (a transmission / reception buffer b for each station, etc.) of a predetermined address for each station, and each station corresponds to its own station in the transmission / reception buffer of its own station. The transmission data in the individual storage area (hereinafter referred to as transmission buffer for each station) is transmitted to each other station, and each other station corresponds to the transmission station of this transmission data in the transmission / reception buffer of its own station. In the broadcast transmission system for temporarily storing in the individual storage area, one of the stations (such as Ti) is set as a master station before the start of the broadcast transmission. Then, the master station receives at least the address data of the station-specific transmission buffer of the station from each station other than its own station, and checks whether or not there is an overlap between the areas of the station-specific transmission buffer. , The station number data of all the stations that can participate in transmission are transmitted to each of the stations (hereinafter referred to as stations that can participate in transmission) confirmed to have no duplication, and thereafter, the broadcast between the stations that can participate in transmission is performed. The transmission shall be performed ”.
この発明はブロードキャスト伝送をしようとする局の中
からマスタとなる局を選び、このマスタとなった局が、
他の局に対して伝送への参加を問合わせた時に、局別送
信バッファ領域の重複チェックを行い、重複していれば
マスタ局がデータ伝送に参加しようとする局のうちその
局（異常局）を除いた各局（伝送参加可能局）の局番リ
ストを伝送参加可能局に送信することにより、異常局を
ブロードキャスト伝送に参加させないようにしようとす
るものである。This invention selects a master station from the stations that intend to perform broadcast transmission, and the master station is
When inquiring other stations to participate in transmission, the station's transmission buffer area is checked for duplication. By sending the station number list of each station (transmission-participable station) excluding the) to the transmission-participable station, the abnormal station is prevented from participating in the broadcast transmission.
以下第１図，第２図に基づいて本発明の実施例を説明す
る。第１図，第２図はそれぞれ本発明の一実施例として
の局間のデータの流れの説明図である。この各図におけ
る矢印がデータの流れの方向を示している。またこの各
図内の各局Ｔは第３図と同様な構成の送受信バッファＢ
を備えているが、第１図，第２図では省略されている。 第１図において局Ｔ（Ｔ１〜Ｔｎ）は共通のリンクＬを
介してブロードキャスト伝送を行おうとする局である。
ここで局Ｔｉをマスタにしたとすると、マスタ局Ｔｉは
ブロードキャスト伝送の開始に先立ち、他の局Ｔ１〜Ｔ
ｎに対して、順々にブロードキャスト伝送に参加するか
どうか問合わせを受けた局は、その応答の中に自局の送
受信バッファＢ（図外）内における、少なくとも自局の
送信データ格納領域としての局別送信バッファｂのアド
レス情報を入れて返す。マスタ局Ｔｉはこの応答の中の
各局の局別送信バッファ領域のアドレス情報をチェック
し、すでに問合せを行った局との間でこの領域の重複が
無いかどうかを判断する。もしこの時、重複していれ
ば、その局（異常局という）をブロードキャスト伝送に
参加させることをしない。即ちマスタ局Ｔｊは例えば局
Ｔ１〜Ｔｎのうち前記の異常局を除いた局（伝送参加可
能局という）に対し伝送参加可能局の局番リストを送信
する。これにより例えば第２図のように局Ｔ３が前記の
異常局であることが検出されたとすると、マスタ局Ｔｉ
は局Ｔ３のブロードキャスト伝送への参加をさせないた
め、データの送受は局Ｔ３を除いた局Ｔ１〜Ｔｎの間
で、第２図の矢印のように行われる。An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. 1 and 2 are explanatory views of the flow of data between stations as one embodiment of the present invention. The arrow in each figure shows the direction of data flow. Further, each station T in each figure is a transmission / reception buffer B having the same configuration as that in FIG.
Is provided, but is omitted in FIGS. 1 and 2. In FIG. 1, stations T (T1 to Tn) are stations that are going to perform broadcast transmission via a common link L.
If the station Ti is set as a master here, the master station Ti will receive other stations T1 to T before starting the broadcast transmission.
In response to the request, the station, which receives inquiries about whether or not to participate in the broadcast transmission in sequence, receives at least the transmission data storage area of its own station in the transmission / reception buffer B (not shown) of the station. And returns the address information of the station-specific transmission buffer b. The master station Ti checks the address information of the station-specific transmission buffer area of each station in this response, and determines whether or not there is duplication of this area with the station that has already made an inquiry. At this time, if they overlap, the station (called an abnormal station) is not allowed to participate in the broadcast transmission. That is, the master station Tj transmits a station number list of stations that can participate in transmission to stations (referred to as stations that can participate in transmission) excluding the abnormal station among the stations T1 to Tn. As a result, if it is detected that the station T3 is the abnormal station as shown in FIG. 2, the master station Ti
Does not allow the station T3 to participate in the broadcast transmission, data is transmitted and received between the stations T1 to Tn except the station T3 as shown by the arrow in FIG.
本発明によればブロードキャスト伝送を行わせようとす
る局の内の一局をマスタ局とし、この伝送を開始するに
先立ってマスタ局が他の各局からその局の送受信バッフ
ァＢ内の少なくとも送信データ記憶領域としての局別送
信バッファｂのアドレス情報を受取って、送受信バッフ
ァＢ内に各局別に設定された局別送受信バッファ領域の
重複チェックを行うようにしたので、局別送受信バッフ
ァ領域が重複したまま、間違った送受信データを使って
システムが稼動することが無くなる。また重複した局別
送受信バッファ領域をもつ局はブロードキャスト伝送に
参加することが無いため、新たな局がブロードキャスト
伝送に参加しようとする時にもこの新たなシステム構成
でのブロードキャスト伝送を開始するに先立って前記と
同様な局別送受信バッファ領域の重複チェックを行うの
で、現在稼動中のシステムのデータを壊さないという効
果が得られる。According to the present invention, one of the stations to be broadcast-transmitted is the master station, and prior to starting this transmission, the master station sends at least the transmission data in the transmission / reception buffer B of each station from the other stations. Since the address information of the transmission buffer b for each station as a storage area is received and the duplication check of the transmission / reception buffer area for each station set for each station in the transmission / reception buffer B is performed, the transmission / reception buffer area for each station remains duplicated. , The system will not operate with wrong send / receive data. Also, since stations with overlapping station-specific transmit / receive buffer areas do not participate in broadcast transmission, even when a new station tries to participate in broadcast transmission, it is necessary to start broadcast transmission with this new system configuration. Since the same duplication check of the transmission / reception buffer area for each station is performed as described above, it is possible to obtain the effect of not destroying the data of the system currently in operation.
第１図，第２図は本発明の一実施例としての局内のデー
タの流れを示す図、第３図，第４図は送受信バッファ内
の局別送受信バッファ間のデータの授受の説明図であ
る。 Ｔ（Ｔ１〜Ｔｎ）：局、Ｂ（Ｂ１〜Ｂｎ）：送受信バッ
ファ、ｂ（ｂ11〜ｂnn）：局別送受信バッファ、（ｂ1
1，ｂ22，ｂ33〜ｂnn：局別送信バッファ）。1 and 2 are diagrams showing a flow of data in a station as an embodiment of the present invention, and FIGS. 3 and 4 are explanatory diagrams of data transmission / reception between station-specific transmission / reception buffers in a transmission / reception buffer. is there. T (T1 to Tn): station, B (B1 to Bn): transmission / reception buffer, b (b11 to bnn): transmission / reception buffer for each station, (b1
1, b22, b33 to bnn: transmission buffer for each station).
Claims (1)
記憶する送受信バッファであって、前記の局ごとに予め
定められたアドレスの個別記憶領域を持つ送受信バッフ
ァを備え、 前記の各局は自局の前記送受信バッファ内における自局
に対応する前記個別記憶領域（以下局別送信バッファと
いう）内の送信データを他の各局へ送信し、該他の各局
は該送信データを自局の前記送受信バッファ内における
この送信データの送信局に対応する前記個別記憶領域へ
一時格納するブロードキャスト伝送のシステムにおい
て、 前記のブロードキャスト伝送を開始するに先立って、前
記の局の１つをマスタ局とし、 該マスタ局は自局を除く他の各局から、少なくとも当該
局の前記局別送信バッファについてのアドレスデータを
受信して、前記局別送信バッファの領域間に重複がある
か否かを調べ、この重複が無いことが確認された局（以
下伝送参加可能局という）の各々へ、該伝送参加可能局
の全てについての局番データを送信し、 以後、前記伝送参加可能局間で前記のブロードキャスト
伝送を行わせるようにしたことを特徴とするブロードキ
ャスト伝送システムのデータ保護方法。1. A plurality of stations, each station is a transmission / reception buffer for temporarily storing transmission data of each station including its own station, and an individual storage area of an address predetermined for each station. Each station has its own transmission / reception buffer, and each station transmits the transmission data in the individual storage area (hereinafter referred to as a transmission buffer for each station) corresponding to the own station in the transmission / reception buffer of the own station to each of the other stations. In a broadcast transmission system in which each station temporarily stores the transmission data in the individual storage area corresponding to the transmission station of the transmission data in the transmission / reception buffer of the station, before starting the broadcast transmission, One of the stations is a master station, and the master station receives at least the address data of the station-specific transmission buffer of the station from each station other than its own station. Data is received, and it is checked whether or not there is an overlap between the areas of the transmission buffer for each station, and the transmission participation is made to each of the stations (hereinafter referred to as transmission participation possible stations) confirmed to have no overlap. A data protection method for a broadcast transmission system, characterized in that station number data for all possible stations are transmitted, and thereafter, the broadcast transmission is performed between the stations that can participate in transmission.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62178243A JPH0646734B2 (en) | 1987-07-17 | 1987-07-17 | Data protection method for broadcast transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62178243A JPH0646734B2 (en) | 1987-07-17 | 1987-07-17 | Data protection method for broadcast transmission system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6422139A JPS6422139A (en) | 1989-01-25 |
| JPH0646734B2 true JPH0646734B2 (en) | 1994-06-15 |
Family
ID=16045095
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62178243A Expired - Fee Related JPH0646734B2 (en) | 1987-07-17 | 1987-07-17 | Data protection method for broadcast transmission system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0646734B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0693685B2 (en) * | 1989-06-14 | 1994-11-16 | 株式会社日立製作所 | Frame selective reception method |
| JP2519535B2 (en) * | 1989-06-27 | 1996-07-31 | 東洋機械金属株式会社 | Molding machine mechanical safety device |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57176861A (en) * | 1981-04-24 | 1982-10-30 | Hitachi Ltd | Terminal equipment |
| JPS59117846A (en) * | 1982-12-24 | 1984-07-07 | Nec Corp | Data communicating equipment |
| JPH0720116B2 (en) * | 1985-01-14 | 1995-03-06 | 日本電気株式会社 | Data transmission / reception method using multiple loops |
| JPS61270947A (en) * | 1985-05-27 | 1986-12-01 | Nippon Telegr & Teleph Corp <Ntt> | Control system for network |
-
1987
- 1987-07-17 JP JP62178243A patent/JPH0646734B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6422139A (en) | 1989-01-25 |
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| R250 | Receipt of annual fees |
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