JPH01248891A - Encipherment key delivery system - Google Patents

Abstract

PURPOSE:To instantaneously deliver work keys to all receivers and to shorten the delivery time of the work keys at long cycles by composing inherent keys of common keys for the all receivers and different keys at every receiver, giving the work keys ciphered with the common keys for the receivers to the all receivers, and transmitting individual information other than the work key with enciphering by means of the different key at every receiver. CONSTITUTION:In a ciphering device 103, common individual information KJ0 including a work key Kw is ciphered by a Km0, and converted into a signal eKJO. Individual information KJp different at every receiver is ciphered by a key KMp different at every receiver, and converted into a signal eKJp. On the other hand, on a receiving side, the transmitted signals eKJ0 and eKJp are decoded by the common key Km0 and the key Kmp different at every receiver in a decoder 106, and KJp and KJ0 are taken off. Further, the individual information KJp and program information BJ are compared by a comparator/collator 108. As a result, only when contract conditions correspond to watching permitting conditions, a switch 109 is conducted, and a scrambler key ks is outputted.

Description

Translated fromJapanese

【発明の詳細な説明】［産業上の利用分野］本発明は送信側で鍵によってスクランブルされた放送番
組データを受信側で１スクランブルするための暗号化鍵
配送方式に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an encryption key distribution system for scrambling broadcast program data scrambled by a key on the transmitting side once on the receiving side.

８［従来の技術］第２図は従来のスクランブル用暗号化鍵の配送方式を示
している。第２図中、左側は送信側を示し、右側は受信
側を示している。8 [Prior Art] FIG. 2 shows a conventional scrambling encryption key distribution system. In FIG. 2, the left side shows the transmitting side, and the right side shows the receiving side.

送信側において暗号化のための鍵はスクランブル鍵ＫＳ
とワーク鍵Ｋｗと固有１１Ｋｍｐの３種類の鍵が存在す
る。番組データＢＤは、受信者共通の放送番組データで
あり、スクランブラ１０１においてスクランブル鍵ＫＳ
でスクランブルされ信号ｅＢＤに変換される。ＢＪは受
信者共通の番組に付随した番組情報であり、この番組情
報ＢＪは視聴許可条件（例えば番組価格、視聴条件のコ
ード等）とスクランブル鍵ＫＳ等で構成される。番組情
報ＢＪは暗号器１０２においてワーク鍵ＫＷによって略
号化され信号ｅＢＪに変換される。上記スクランブル鍵
ＫＳは通常約１秒位で更新される短周期の鍵である。ま
た、個別情報（ＫＪ）群の中のＫＪｐは、特定の受信者
ｐ（例えばｐさん）固有の個別情報であり、この個別情
報ＫＪｐは、契約条件（支払い金額、有効日数、視聴条
件のコード等）とワーク鍵ＫＷ等で構成され、暗号器１
０３において受信者ｐの固有鍵Ｋｍｔ）で暗号化され信
号ｅＫＪ　ｐに変換される。上記ワーク鍵ＫＷは通常約
１カ月位で更新される長周期の鍵である。The key for encryption on the sending side is the scramble key KS.
There are three types of keys: 1, a work key Kw, and a unique 11Kmp. The program data BD is broadcast program data common to all receivers, and the scrambler 101 uses the scramble key KS.
The signal is scrambled and converted into a signal eBD. BJ is program information attached to a program common to all recipients, and this program information BJ is composed of viewing permission conditions (for example, program price, viewing condition code, etc.), a scramble key KS, and the like. Program information BJ is abbreviated in encoder 102 using work key KW and converted into signal eBJ. The scramble key KS is a short-cycle key that is normally updated every about 1 second. In addition, KJp in the individual information (KJ) group is individual information unique to a specific recipient p (for example, Mr. etc.) and a work key KW, etc., and the encryptor 1
03, the signal is encrypted using the unique key Kmt of the receiver p and converted into a signal eKJp. The work key KW is a long-period key that is normally updated every about one month.

第２図中個別情報（ＫＪ）群はＫＪｌ、ＫＪ２゜・・・
・・・ＫＪｎで構成され（ｎは受信者数）、ＫＪＩ）は
ＫＪ群のいずれか一つを表わす。ＫＪ群のすべてはそれ
ぞれ暗号器１０３で固有鍵（Ｋｍ）群の対応する固有鍵
で暗号化されｅｋＪ群となる。受信者固有の鍵群は、各
受信者が１個ずつ保有しているＩ！Ｋｍ　ｌ　、　Ｋｍ
　２　、　””’−，Ｋｍ　Ｏ，”””。In Fig. 2, the individual information (KJ) group is KJl, KJ2゜...
...KJn (n is the number of recipients), and KJI) represents any one of the KJ groups. All of the KJ groups are each encrypted by the encoder 103 with the corresponding unique keys of the unique key (Km) group to form the ekJ group. The receiver-specific key group is I!, which each receiver owns one key group. Km l, Km
2, ``”'-, Km O, ``''''.

Ｋｍｎで構成される。It consists of Kmn.

上記の信号ｅＢＤ、ｅＢＪの多数（７）　ｅ　Ｋ　Ｊ　
ハ、合成１１０４で合成された後、各受信６宛に配送さ
れる。Many of the above signals eBD, eBJ (7) e K J
c. After being combined in the combining step 1104, the signals are delivered to each receiver 6.

一方、受信側においては、各受信考究に配送された信号
ｅＢＤ、ｅＢＪと多数のｅｋＪは、分離器１０５で選択
分離され、信号ｅＢＤ、ｅＢＪ及び自分宛の情報ｅＫＪ
ｐのみを抽出する。最初にｅＫＪｐが復号器１０６で受
信者ｐの固有鍵ｋｍｐで元のＫＪｐに復号化される。次
に（３ＢＪが、復号器１０７において、ＫＪｐの中に含
まれる受信者共通のワークＩＩＫｗを用いて元のＢＪに
復号化される。最後に、前記ＫＪに含まれた契約条件と
ＢＪに含まれた視聴許可条件とが比較照合器１０８にお
いて一致すると判定された場合にのみ切替器１０９が導
通状態になり、デスクランブラ１１０においてｅＢＤが
ＢＪの中に含まれるスクランブル鍵によって１スクラン
ブルされる。このようにして受信者側にて元の番組デー
タＢＤが取り出され、視聴される。On the other hand, on the receiving side, the signals eBD, eBJ and a large number of ekJs delivered to each receiving study are selectively separated by a separator 105, and the signals eBD, eBJ and information eKJ addressed to itself are separated by a separator 105.
Extract only p. First, eKJp is decrypted by the decryptor 106 to the original KJp using the unique key kmp of the recipient p. Next, (3BJ is decoded into the original BJ in the decoder 107 using the work IIKw that is common to the recipients and is included in KJp.Finally, the contract conditions included in the KJ and the Only when the comparator 108 determines that the viewing permission conditions match the selected viewing permission conditions, the switch 109 becomes conductive, and the descrambler 110 scrambles the eBD using the scramble key contained in the BJ. In this way, the original program data BD is taken out and viewed on the recipient side.

［発明が解決しようとする問題点］前述した従来の鍵配送方式では、例えば受信者が１００
０万人であるとすると、仮に１つの伝送路でのワークＲ
Ｋｗの配送能力が１時間に１００万人であったとしても
、ワーク鍵を各受信者の固有鍵で暗号化して各受信者ご
とに個別に配送しているので、すべての受信者にワーク
鍵Ｋｗを配送するには最低でも１０ＩｉＦｌを必要とす
る。また、受信者が常時受信待機をすることができない
場合や伝送路で生じるエラーを考慮してワーク鍵を数回
送出する場合にはワークＩＩＫＷの配送時間として数＋
Ｒ１１以上の時間が必要となる。このように従来の鍵配
送方式では、受信者が多数の場合ワーク鍵を送出するた
めの時間が問題となり、−伝送路だけではり−クＩＩＫ
ｗをすべての受信者に短時間で配送することができない
という欠点を有している。[Problems to be Solved by the Invention] In the conventional key distribution method described above, for example, if the recipient is 100
Assuming that there are 00,000 people, if the work R on one transmission line is
Even if Kw's delivery capacity is 1 million people per hour, the work key is encrypted with each recipient's unique key and delivered individually to each recipient, so the work key cannot be sent to all recipients. Delivery of Kw requires at least 10IiFl. In addition, if the recipient cannot always wait for reception or if the work key is sent several times in consideration of errors that occur on the transmission path, the delivery time of the work IIKW is set to several +
A time longer than R11 is required. In this way, in the conventional key distribution method, when there are many recipients, the time required to send out the work key becomes a problem, and the transmission path alone is insufficient.
It has the disadvantage that w cannot be delivered to all recipients in a short time.

本発明の目的は、受信珈が多数であってもワークＩ！Ｋ
Ｗを短時間で配送することのできる暗号化鍵配送方式を
提供することにある。An object of the present invention is to provide a work I! K
The purpose of the present invention is to provide an encryption key distribution method that can deliver W in a short time.

Ｅ問題点を解決するための手段］本発明に係る暗号化鍵配送方式は、受信側では個別情報
の契約条件と番組情報の視聴許可条件とが一致するとい
う条件の下でスクランブル鍵が取り出されることを考慮
して、固有鍵を受信者共通の鍵と受信者ごと異なる鍵で
構成し、ワーク鍵を受信者共通の鍵で暗号化して受信者
全員に与えることとし、ワーク鍵以外の個別情報は受信
者ごと異なる鍵で暗号化し伝送するように構成される。Means for Solving Problem E] In the encryption key distribution method according to the present invention, the scramble key is extracted on the receiving side under the condition that the contract conditions of individual information and the viewing permission conditions of program information match. Taking this into consideration, the unique key consists of a key common to all recipients and a different key for each recipient, and the work key is encrypted with a key common to all recipients and given to all recipients, and individual information other than the work key is is configured to be encrypted and transmitted using a different key for each recipient.

［実施例］以下に本発明の実施例を添付図面に従って説明する。[Example]Embodiments of the present invention will be described below with reference to the accompanying drawings.

第１図は本発明に係る暗号化鍵配送方式を示すプロツク
図であり、第１図中左側に送信側装置を、右側に受信側
装置を示す。第１図において、経木的構成は第２図で示
した従来のものと同じであるので、第１図中第２図で示
した同一要素には同一符号を付し、その詳細な説明を省
略する。すなゎち、１０１は番組データＢＤをスクラン
ブルするスクランブラ、１０２は番組情報ＢＪを暗号化
する暗号器、１０３は個別情報を暗号化する暗号器、１
０４は合成器、１０５は分離器、１０６は個別情報を復
号する復号器、１０７は番組情報を復号する復号器、１
０８は比較照合器、１０９は切替器、１１０はデスクラ
ンブラである。Ｌ記の各構成要素の機能は従来技術の箇
所で説明した通りである。FIG. 1 is a block diagram showing an encryption key distribution system according to the present invention. In FIG. 1, the left side shows a transmitting side device, and the right side shows a receiving side device. In Fig. 1, the structural structure is the same as the conventional one shown in Fig. 2, so the same elements shown in Fig. 1 and Fig. 2 are denoted by the same reference numerals, and detailed explanation thereof will be omitted. do. That is, 101 is a scrambler that scrambles the program data BD, 102 is an encoder that encrypts the program information BJ, 103 is an encoder that encodes individual information, 1
04 is a combiner, 105 is a separator, 106 is a decoder that decodes individual information, 107 is a decoder that decodes program information, 1
08 is a comparison/verification device, 109 is a switch, and 110 is a descrambler. The functions of each component listed in L are as explained in the prior art section.

次に本発明の特徴的部分を説明する。送信側の固有鍵（
Ｋｍ）群には、各受信者ごとに異ならせた固有ＩＫｍｌ
　、Ｋｍ２．−−−−−−Ｋｍｐ、−−−−−−Ｋｍｎ
と受信者のすべてに共通するｌＩＫｍＯとが含まれる。Next, characteristic parts of the present invention will be explained. Sender's unique key (
Km) group has a unique IKml that is different for each recipient.
, Km2. -------Kmp, ------Kmn
and lIKmO common to all recipients.

上記においてｎは整数で受信者の数を表わし、ｐは任意
の受信賃を表わす符号である。In the above, n is an integer representing the number of recipients, and p is a code representing an arbitrary reception fee.

暗号器１０３は個別情報（ＫＪ）群の中に含まれる個別
情報ＫＪｐの暗号化を行うが、この場合にはワークＩ！
Ｋｗを含む共通の個別情報ＫＪＯとそれ以外の個別情報
ＫＪＤとを別々に暗号化する。The encoder 103 encrypts the individual information KJp included in the individual information (KJ) group, but in this case, the work I!
Common individual information KJO including Kw and other individual information KJD are separately encrypted.

すなわち、暗号！１０３においてワーク鍵ＫＷを含む共
通の個別情報ＫＪＯは鍵ＫｍＯで暗号化されて信号ｅＫ
Ｊｏに変換され、他の゛受診者ごとに異なる個別情報Ｋ
Ｊｐは受信者ごとに異なる鍵Ｋｍｐによって暗号化され
信号ｅＫＪｐに変換される。In other words, cryptography! In 103, the common individual information KJO including the work key KW is encrypted with the key KmO and sent as a signal eK.
This information is converted into JO and other individual information K that differs for each patient.
Jp is encrypted using a different key Kmp for each recipient and converted into a signal eKJp.

一方、受信側においては、復号器１０６で、伝送されて
きた上記信号ｅＫＪｏとｅＫ、ＪＤとを、各受信者に設
けられた共通のＩＩＫｍＯと受信者ごとに異なる鍵Ｋｍ
ｐとでそれぞれ復号化し、ＫＪｐとＫＪＯを取り出す。On the other hand, on the receiving side, the decoder 106 converts the transmitted signals eKJo, eK, and JD into a common IIKmO provided for each receiver and a key Km, which is different for each receiver.
p and extract KJp and KJO.

そして個別情報ＫＪＯのワークＩ！Ｋｗを用いて復ｊ３
器１０７で番組情報ＢＪを取り出し、比較照合器１０８
で個別情報ＫＪｐと番組情報ＢＪを比較し、契約条件と
視聴許可条件が一致したときにのみ切替器１０９を導通
させ、スクランブラ鍵Ｋｓを出力させる。And individual information KJO's work I! revenge using Kw
The program information BJ is taken out by the device 107 and compared and verified by the comparison device 108.
The individual information KJp and the program information BJ are compared, and only when the contract conditions and the viewing permission conditions match, the switch 109 is made conductive and the scrambler key Ks is output.

上記の実施例において、受信者に共通の鍵ＫｍＯは全受
信者に対して共通としたが、全受信者を複数のブロック
に分け、ブロックごとに異なる鍵を設け、゛複数の鍵と
して構成できる。このように必要に応じて受信者に共通
な鍵を数個以上使用することもできる。In the above embodiment, the key KmO common to all recipients is common to all recipients, but it is also possible to divide all recipients into multiple blocks and provide a different key for each block, thereby configuring the key KmO as multiple keys. . In this way, several or more keys common to recipients can be used if necessary.

［発明の効果１以上の説明で明らかなように本発明によれば、固有鍵の
中に受信者に共通な鍵を用意し、この鍵でワーク鍵を暗
号化するようにしたため、ワーク鍵を瞬時に全受信者に
配送でき、長周期のワーク鍵の配送時間を大幅に短縮で
きる。また、受信者が１力月単位の短期契約であっても
、必要な時期に随時ワーク鍵を変更できるという効果も
発揮される。[Effect of the invention 1] As is clear from the above explanation, according to the present invention, a key common to recipients is prepared in the unique key, and the work key is encrypted with this key. It can be delivered to all recipients instantly, greatly reducing the delivery time for long-cycle work keys. Furthermore, even if the recipient has a short-term contract of one month, the work key can be changed at any time as needed.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明に係る暗号化鍵配送方式を説明するため
のプ【コック図、第２図は従来の暗号化鍵配送方式を説明するためのブロ
ック図である。［符号の説明］１０１・・・・・・スクランブラ１０２．１０３・・・・・・暗号器１０４・・・・・・合成器１０５・・・・・・分離器１０８．１０７・・・−復号器１０８・・・・・・比較照合器１１０・・・・・・デスクランブラFIG. 1 is a block diagram for explaining the encryption key distribution method according to the present invention, and FIG. 2 is a block diagram for explaining the conventional encryption key distribution method. [Explanation of codes] 101...Scrambler 102.103...Encryptor 104...Synthesizer 105...Separator 108.107...- Decoder 108... Comparison/verifier 110... Descrambler

Claims (1)

Translated fromJapanese

【特許請求の範囲】[Claims]（１）番組データにスクランブルをかけるためのスクラ
ンブル鍵と、このスクランブル鍵を含む番組情報を暗号
化するワーク鍵と、このワーク鍵を含む個別情報を暗号
化する固有鍵とによつて暗号化が行われ、暗号化された
前記スクランブル鍵と前記ワーク鍵とを各受信者へ伝送
する暗号化鍵配送方式において、前記固有鍵は受信者共通の鍵と受信者ごとに異なる鍵と
から成り、送信側において前記ワーク鍵は受信者共通の
鍵によつて暗号化されると共にワーク鍵以外の前記個別
情報は受信者ごとに異なる鍵によつて暗号化され、一方
各受信者の側では前記固有鍵として前記の受信者共通の
鍵と受信者ごとに異なる鍵を備え、前記個別情報を受信
者共通の鍵によつて復号化することによりワーク鍵を抽
出し、また前記個別情報を受信者ごとに異なる鍵によつ
て復号化することにより受信者の個別情報を抽出し、抽
出された前記ワーク鍵で復号化された番組情報内の視聴
許可条件と前記受信者の個別情報内の受信契約条件とが
合致したとき前記ワーク鍵で抽出されたスクランブル鍵
をデスクランブラに与えることを特徴とする暗号化鍵配
送方式。(1) Encryption is performed using a scramble key for scrambling program data, a work key for encrypting program information containing this scramble key, and a unique key for encrypting individual information containing this work key. In an encryption key distribution method in which the scramble key and the work key that have been encrypted and encrypted are transmitted to each recipient, the unique key consists of a key that is common to the recipients and a key that is different for each recipient; On the side, the work key is encrypted with a key common to the recipients, and the individual information other than the work key is encrypted with a key that differs for each recipient, while on the side of each recipient, the unique key The above-mentioned common key for the receivers and a different key for each receiver are provided, and the work key is extracted by decrypting the individual information with the key common to the receivers, and the individual information is extracted for each receiver. The receiver's individual information is extracted by decrypting it with a different key, and the viewing permission conditions in the program information and the reception contract conditions in the receiver's individual information decrypted with the extracted work key are extracted. An encryption key distribution system characterized in that when the above-mentioned work key matches, a scramble key extracted using the work key is given to a descrambler.