Method of transmitting and receiving multimedia content
FIELD: information technology.
SUBSTANCE: method includes steps of: a transmitter using an operating key and an encryption algorithm executable code in a virtual mother card to encrypt a control word CWt to obtain a cryptogram
EFFECT: safer data transmission.
14 cl, 6 dwg
The present group of inventions relates to a method for transmitting and receiving multimedia content. The present group of inventions relates also to a method of generating messages ECM (message control rights) and method of reception of messages ECM. Finally, the present group of inventions relates to the transmitter, the receiving terminal device and the recording medium information for the implementation of these methods.
The present group of inventions can be applied, in particular, in the field of access control to provide paid media programs, such as pay-TV.
In the present description, the term "multimedia content" more specifically refers to audio and/or visual content that is intended for display in a form directly perceived and understood by the people. Usually multimedia content corresponds to the sequence of images forming a film, a television program broadcast or advertising. Multimedia content can also be an interactive content, such as game.
To protect multimedia content from view and the limitations of such viewing conditions, such as, for example, a paid subscription, multimedia content broadcast on channels broadcast in scribblearea the nom, and not in the clear or in an open form. In the present description, the channel is called "scrambled" if the scrambled media content transmitted in the broadcast mode on this channel.
More specifically, each of the multimedia content is divided into a sequence of cryptoperiods. Throughout the duration of this cryptoperiod access to scrambled media content remain unchanged. In particular, in the continuation of one of cryptoperiod multimedia content scrambling using the same control word. In General, when you move from one cryptoperiod to another is a change of such a control word.
Moreover, the control word in the General case is specific to any media content, but such control word form random or pseudo-random manner. Thus, if at some point N multimedia content transfer mode broadcast simultaneously over N channels, there are N different independent control words, each of which is used for scrambling of one of the multimedia content.
Here, the word "scramble" and "encrypt" are considered synonymous. The same applies to the terms "descrambling" and "decrypt".
the open media content corresponds to the media content prior to scrambling. This content can be made directly human-readable, without resorting to the operations diskriminirovaniya and without limiting the view to certain conditions.
Control words necessary to diskriminirovaniya media content, transmit synchronously with the specified multimedia content. For example, the control words necessary to diskriminirovaniya tthcryptoperiod, take each target device at time (t-1)thcryptoperiod. To this end, for example, control words multiplexer with scrambled multimedia contents.
To protect the transfer of control words, these words convey to the target device in the form of cryptograms, prisoners in message ECM. Here below, the term "cryptogram" refers to the segment information, which by itself is not sufficient to extract unencrypted or open the control word. Thus, if the transmission of the control word is interrupted, knowing only this cryptogram of the control word cannot be used to extract the control word, through which you can descrambling multimedia content.
To extract the public control word, i.e., control word, which can be used for direct diskriminirovaniya the player the applications content this control word must be connected to the segment of the secret information. For example, the cryptogram of the control word can be obtained by encrypting the open control word using the working key and the encryption algorithm. In this case, the specified segment of classified information is a used working key and/or algorithm encrypt decrypt the cryptogram.
This segment of classified information must be stored in a safe place. This has already been proposed to save the segment of classified information in the processor system security, such as a smart card or a virtual card. The term "virtual card" refers to a software component containing a number of resources, including:
the executable code of the algorithm for encryption or decryption algorithm, and
the executable code of the syntax analyzer to determine the location of the cryptogram of the control word in the message ECM or the executable code of the constructor syntax for constructing messages ECM, and
in some cases the access rights
in some cases, a work key that is used as a parameter of the algorithm for encryption or decryption.
The executable code is a code that can be directly executed by the interpreter or virtual the machine on the lower level, implemented in the microprocessor. The algorithm for encryption or decryption and the syntax analyzer usually form an executable program or a set of executable programs.
Here below, the term "virtual parent map" refers to a virtual map that is used to compute messages ECM. The term "virtual child card" means a virtual map that is used to process a received message ECM. Virtual maternal map and virtual sub-map can be associated with one another, if virtual child card can successfully handle received messages ECM calculated by the virtual parent of the map.
In this context, the method of transmitting and receiving multimedia content, each cryptoperiod CPtwhich is scrambled using the appropriate control word CWtknown transmission side, contains:
encryption, on the transmission side, the control word CWtusing the working key and the executable code of the encryption algorithm contained in the virtual parent map to obtain the cryptogram,
generating the message ECM (message control rights), containing the cryptogramby the executable to the and constructor syntax contained in the virtual parent map, and the transmission of this message ECM target device,
receiving messages ECM target device, determining the location of the cryptogramin the accepted message to the ECM via executable code analyzer syntax and then decrypt the cryptogramusing the working key of the decryption algorithm, so that the executable code analyzer syntax and algorithm decryption is contained in the composition of the virtual sub-map associated with the specified virtual parent card, and
diskriminirovaniya of cryptoperiod CPtscrambled multimedia content using the decrypted control word CWt.
The use of virtual cards quickly and with little cost to replace sensitive information terminal devices. For example, replacing the virtual card allows you to modify the algorithms used for encryption and decryption in case of detection of gaps in the security system. However, the mere use of the virtual card does not gain from a security perspective, compared with the use of smart cards.
Known methods described in:
FR 2922393 A1,
EP 1320006 A1,
WO 2009/112966 A2 and
US 2009/080648 A1.
The present and the acquisition is aimed at increasing the security of modes of transmission and the reception of multimedia content using virtual cards.
The present invention thus relates to a method for transmitting and receiving multimedia content, each cryptoperiod CPtwhich is scrambled using the appropriate control word CWtthis method also includes the steps:
change at least every two hours, the transmission side virtual parent card used to obtain the cryptogram. For the next cryptoperiod CPt+nthe same media content, such new used virtual parent map differs from the previously used virtual parent card its working key and at least executable code of your encryption algorithm or constructor syntax
in response to such a change, select the target device to a new virtual sub-maps to use in order to decrypt the cryptogramto obtain the control word CWt+n.
According to the method described here above, the change of the virtual maternal and child cards at least every two hours increases the variety of used keys and algorithms, which makes the extraction of sensitive information by unauthorized users and sharing of this information with the other user is the teli-hackers more complex. In particular, according to the above method, unauthorized and illegal extraction of secret information can be made more difficult not only by the frequent changes of the working key, but due to the frequent change of the encryption algorithm and/or constructor syntax. For example, unauthorized extraction working keys can be made more difficult by changing the constructor syntax, message format, the ESM and, as an example, change the location of this key in the message ECM. As a result of computer pirates becomes more difficult to accurately extract the cryptogram key from the message ECM. Change the encryption algorithm makes unauthorized extracting only the working key is useless, because you just need to remove the encryption algorithm or decryption for use with this key. The amount of information that you want to illegally extract to accurately descrambling multimedia content, as a consequence, increases. At the same time, the frequency of updating this information also increases. Computer hackers as a result becomes more complex, and the security method of transmitting and receiving multimedia content therefore increases.
Variants of the proposed method may have the following characteristics:
- use the may new virtual parent map differs from the previous used virtual maternal cards executable code your algorithm decryption and its constructor syntax.
Variants of the proposed method have the following advantages:
- the combined use of the encryption algorithm and decryption and constructor syntax allows you to encrypt the control word and makes it possible to change the message format ECM (for example, the location of this cryptogram of the control word in the message ECM) to do the deciphering this message ECM is more difficult for an unauthorized user.
The present invention also relates to a method of generating messages ECM with the aim of implementing the transmission method of multimedia contents, so that every message ECM contains a cryptogramthe control word CWtused for scrambling the corresponding cryptoperiod CPtthe same media content, the method includes:
a) encryption of the control word CWtusing the working key and the executable code of the encryption algorithm contained in the virtual parent map, to obtain the cryptogramand
b) generating messages ECM containing the cryptogramusing the executable code in the constructor of the synthesis contained in the virtual parent map, and
c) changing at least every two hours the virtual parent card, used to obtain the cryptogramfor the next cryptoperiod CPt+nso used the new virtual parent map differs from the previous used virtual parent card working key and executable code of the cryptographic algorithm or constructor syntax.
Variants of this method may have one or more of the following characteristics:
the method includes transmitting to the target device, in a message ECM, ID virtual child card that you want to use to decrypt the cryptogram.
- in stage C), the virtual parent map choose from a variety of virtual cards, pre-recorded in the device of the transmitter, so that a virtual card belonging to this set differ from one another.
- in stage C), the virtual parent map choose a pseudo-random manner from a variety of virtual cards, pre-recorded in the transmitter device.
- when you do this:
the method comprises a stage on which is chosen, as a function of the media content that you want to scramble, many of several different virtual maternal cards from the set of the multiple sets of virtual parent cards with use of the cation ratio, associating each media content with only one of many virtual parent cards, with each virtual parent map belongs exclusively to one set, and
control word for scrambling a multimedia content encrypt exclusively through the virtual parent of cards selected from the set associated with this content to restrict access to the scrambled media content solely those receiving terminal devices, which have a number of virtual sub-maps associated with this multiple virtual parent cards.
Variants of the proposed method have moreover the following benefits:
when the virtual identifier of the parent card is passed in a message ECM, you can increase the frequency of changes in one virtual card to another virtual card
- when the virtual parent maps stored in advance, the switching time at the level of the transmitter between the previous virtual parent card and the new virtual parent card becomes minimum,
- when the virtual parent map choose a pseudo-random manner, the degree of safety of the method increases as it makes it difficult for nesans tonirovannogo user clarification in advance which of the associated virtual child card will be the card that you want to use to decrypt the subsequent cryptogram, and
when all virtual sub-maps stored in advance, the switching time at the level of the target device between the previous virtual child card and a new virtual child card becomes minimum.
The present invention relates also to method of receiving, by the target device, for implementing the above described method for transmission and reception, this method contains:
e) receiving, at the one or more messages ECM, cryptogramfor the control word CWt,
f) determining the location of the cryptogramin part a received message, the ESM, by the executable code of the syntax analyzer and then decrypt this cryptogram using the public key and the executable code of the decryption algorithm, while the executable code analyzer syntax and algorithm decryption is contained in the composition of the virtual sub-map associated with the transmitting virtual parent card, and diskriminirovaniya of cryptoperiod CPtaccept scrambled multimedia content using the decrypted control word CWsub> tand
g) in response to changes in the virtual parent card in the transmitter, select the target device to a new virtual sub-map to use for decrypting the cryptogrammany virtual child cards, pre-recorded in the target device, to obtain the control word CWtso that each virtual sub-map in any many different from any other virtual child card of this set its a work key and at least executable code your algorithm decryption or analyzer syntax.
Variants of this method can have one or more of the following characteristics:
the method comprises the steps are:
take the ID of the virtual sub-cards at the stage e), and
select the virtual child map from a set of pre-recorded cards based on the specified identifier received during step g).
the method also includes:
receiving target device in step (e), one or more additional commands, and
in response to this, the modification of the executable code of the selected virtual sub-maps by completing and/or replace only one part of commands executable code that virtual child cards accepted by command or multiple commands.
the method includes:
h) receiving an encrypted virtual child card target device,
i) save a received encrypted virtual child cards, to add this card to many pre-recorded virtual child cards, and
(j) decoding the specified encrypted virtual child card in response to receiving the specified identifier,
steps h), i) and (j) perform first implementation steps f) and g).
Variants of this method have the following advantages:
- if the method contains the above-described mechanism for additional commands, this method is additionally protected.
Finally, the method relates to the recording medium information contains the command to implement one of the methods presented here above, when these commands performs electronic computer.
The present invention also relates to a transmitter for implementing the method of generating messages ECM, this transmitter contains:
block scrambling to implement scrambling appropriate cryptoperiod CPtmultimedia content using the control word CWt,
a system for encryption of the control word CWtusing the working key and the executable code of the encryption algorithm contained in the Ostrava virtual parent card, to obtain the cryptogramand to generate messages ECM containing the cryptogramwith the use of the executable code in the constructor syntax contained in the virtual parent card, the system is programmed to change the used virtual parent card at least every two hours with the purpose of obtaining a cryptogramfor the next cryptoperiod CPt+nwhile new used virtual parent map differs from the previous mother used virtual cards work key and at least executable code of your encryption algorithm or constructor syntax.
The present invention finally relates to a receiving terminal device, containing:
many pre-recorded virtual child cards,
the receiver is designed to receive, via one or more messages ECM, cryptogramthe control word CWt+nand
an integrated circuit programmed to:
locate the cryptogramin part a received message, the ECM via executable code analyzer syntax and then decrypt this cryptogr the guide using the working key and the executable code of the algorithm decryption so the executable code analyzer syntax and algorithm decryption is contained in the composition of the virtual sub-map associated with the virtual parent card, and
diskriminirovaniya of cryptoperiod CPtthe multimedia content scrambled by using the decrypted control word CWtand
in response to the change of the virtual parent card in the transmitter select a new virtual sub-maps to use in order to decrypt the cryptogramfrom a variety of pre-recorded virtual child cards, to obtain the control word CWt+nso that each virtual sub-map is different from any other virtual child card of this set its a work key and at least executable code your algorithm decryption or its syntax analyzer.
Other characteristics and advantages of the present invention will become clearer from the description given below by way of examples, in no way being exhaustive, and with reference to the accompanying drawings, on which:
- Fig.1 is a schematic illustration of a system for transmitting and receiving scrambled multimedia contents,
- Fig.2 is a schematic illustration of the evaluation module for transmitting system, is provided in Fig.1,
- Fig.3 is a schematic illustration of the integrated circuit for transmitting system shown in Fig.1,
- Fig.3A, 3b and 3C are schematic illustrations of the databases and tables that are pre-recorded in a storage device of the integrated circuit shown in Fig.3,
- Fig.4 is a schematic illustration of the associated one with another virtual maternal map and virtual child cards,
- Fig.5 is a logic diagram of a method of transmitting a scrambled multimedia content in the system shown in Fig.1, and
- Fig.6 is a logic diagram of a method of receiving scrambled multimedia content in the system shown in Fig.1.
In these drawings the same reference designators are used to indicate identical elements.
Here below in this description of the characteristics and functions well known to specialists in this field, not described in detail.
Moreover, here we use the common terminology used for conditional access to media content. For additional information regarding these terms, the reader can refer to the following document: "Functional model of a conditional access system" ("Functional Model of a Conditional Access System", EBU Review, Technical European Broadcasting Union, Brussels, BE, n° 266, 1 December 1995).
In Fig.1 shows a system 2 for transmitting and receiving scrambled multimedia content. Here multimedia content are linearized. The term "linear multimedia content" refers to media content for which the user has no control over the time of the transfer. For example, such media content corresponds to the sequence of the audiovisual program, such as a program of a television broadcast, or film.
Open the multimedia content to generate one or more of the sources 4 and transmit the broadcast device 6. This device 6 transmits the received multimedia content simultaneously to multiple receiving terminal devices via the network 8 information transfer. Transmitted in this mode, the broadcast media content is synchronized in time with one other so that, for example, correspond to a predetermined program guide.
The network 8 is typically a network information transfer over long distances, such as the Internet or satellite communication network, or any other broadcasting network such as the network used for transmitting signals of digital terrestrial television (DTTV unit).
In Fig.1 for simplicity, shows only three receiving terminal devices 10 and 12.
Device 6 sod is RIT block 16 encoding, which compresses the received multimedia content. This block 16 encoding processes the digital media content. For example, the coding block operates in accordance with the standard MPEG2 (group of experts on cinematography - 2) or standard UIT-T N.
Compressed media content is directed to the input 20 of the block 22 scrambling. This unit 22 performs scrambling, scrambling each of the compressed media content to do his view was based on certain conditions, such as the acquisition of access rights by users of the receiving terminal devices. Received scrambled multimedia content transmitted to the output 24 connected to the input of the multiplexer 26. The specified unit 22 performs scrambling, scrambling each of the compressed media content using the control word CWi,tsupplied to this block generator 32 of the control words CWi,t. Usually this block scrambling meet the standard, such as DVB-CSA (digital video broadcasting - generalized algorithm scrambling), ISMA Cryp (Alliance for the development of solutions to streaming in the Internet), SRTP (secure data transfer in real time), AES (advanced encryption standard),... and so on
The generator 32 is programmed to:- generate the control word CWi,tand
- transmit the generated control word block 22 scrambling to 28.
In this example, the generator 32 generates a control word CWi,ta pseudo-random way. Here the generator 32 is included in the multiplexer 26.
Here below the index i represents the ID of the channel that is broadcasting a scrambled multimedia contents, and the index t represents a sequence number that identifies cryptoperiod, scrambled using this control word.
The system 28 is better known under the acronym CAS (conditional access system). The system 28 is programmed to:
- generating a cryptogramfor the control word CWi,ttransmitted by the generator 32, and
- generate, for each channel I, the ECM messagesi,t(message rights management), containing at least the cryptogramthe control word CWi,tused by the block 22 scrambling to implement the scrambling cryptoperiod t in channel i.
These messages ECMi,tand the scrambled media content multiplexers through multiplexer 26 and then passed to the network 8.
The system 28 is additionally the painted below with reference to Fig.2.
Message ECM containing the control word CWi,tin the description below labeled ECMi,there:
the index i identifies the channel, and
the index t represents a sequence number that identifies the position of this message ECM on the time axis relative to the other messages ECM transmitted in order to diskriminirovaniya channel
Here, the index t also identifies cryptoperiod CPi,tthat can be descramblers by means of the control word CWi,tcontained in the ECM messagei,t. The index t is unique for each cryptoperiod CPi,t.
The same ID i insert all messages ECMi,tcontaining the cryptogramfor diskriminirovaniya multimedia contents transmitted in the broadcast mode on this channel i. To illustrate, here scrambling and multiplexing of multimedia contents is carried out in accordance with the Protocol DVB-Simulcrypt (ETSI TS 103 197). In this case, the ID i can fit one pair of "channel ID/thread ID" ("channel ID/stream ID"), through which pass all requests to the requirement of generating messages ECM for this channel.
In this example, the target device 10 through 12 are identical. So here below only target at trojstvo 10 is described in more detail.
The target device 10 is described here for the case, when it can descrambling only one channel i. For this purpose, the target device 10 contains a single tract 60 diskriminirovaniya exercising diskriminirovaniya channel i. For example, the path 60 descrambled signal of channel i to represent it on the display device 84 to display.
This device 84 of the display may be, for example, TV, computer, or again landline phone or cell phone. Here as a display device used by the TV.
The path 60 includes a receiver 70 of the broadcast media content. This receiver 70 is connected to the input of the demultiplexer 72, which transmits, on the one hand, media content at block 74 diskriminirovaniya and, on the other hand, messages ECMi,tand EMM (the message on the pre-admission) on an integrated circuit 76.
Integrated circuit 76 is able to decrypt the cryptogramfor the control word CWi,tcontained in the ECM messagei,tand to transmit the received control word at block 74 diskriminirovaniya. This integrated circuit 76 are described in more detail below with reference to Fig.3.
The specified block 74 diskriminirovaniya performs diskriminirovaniya scrambled multimedia content with what ispolzovaniem control word, transferred by the processor 76. Received descrambling multimedia content transmitted to the decoder 80, which performs the decoding of the content. Extended or decoded multimedia content to transmit graphics card 82, which controls the presentation of multimedia content on the device 84 display that has a screen 86. The device 84 display represents multimedia content in an open form on the screen 86.
System 28 will now be described with reference to Fig.2.
The system 28 includes a non-volatile storage device 36. This storage device 36 includes a base 38 and 42 of the data.
The base 38 data represents the ratio of associating, for each index 1, the set Eivirtual cards maternal CMEi,kwhere the index E; identifies a lot, which belongs to a virtual map CMEi,kand k is an integer. Each virtual parent map CMEi,kidentified by ID ICMEi,kwhich is correct only for this virtual parent card. To simplify Fig.2, the base 38 of the data is shown only for the two channels 1 and 2. Many E1and E2contain three pre-recorded virtual parent card, respectively, CM1,1 SEEE1,2CME1,3and CME2,1CME2,2SEEE2,3.
Virtual maternal cards belonging to the same set differ from one another. Preferably, the virtual parent map belonging to the set Eibelongs exclusively to this set Ei. Thus, two virtual maternal cards belonging to two different sets of Ei, necessarily different from one another. The definition of "different from others" is given below with reference to Fig.4.
All virtual maternal cards have a common structure. This structure is given below with reference to Fig.4.
The base 42 of the data contains the so-called "software adjustment. The term "software adjustment" refers to a group of code segments containing at least one command that is used to Supplement or replace portions of the executable code of the virtual parent or subsidiary card. This replacement does not require any re-compile the modified code. Usually such a "correction" is formed from one or more code vectors (or sequences of bytes) variable length, each of which is associated with the target address (or initial position) in the code (continuous area of memory whose contents you want to replace. Ultimately, it seems the t a list of modifications you need to do in the code block.
Here below, the term "maternal adjustment" means the adjustment designed for application code virtual parent card. The term "child adjustment" means the adjustment is intended to apply to code a virtual subsidiary of the map.
For example, correction contains the command that specifies the number of iterations for the algorithm to encrypt or decrypt.
In the example, the size of the memory for software adjustments less than 10 ko and, preferably, less than 5 ko, so that it can be transmitted through messages ECM and/or EMM messages.
The base 42 of the data associated with maternal adjustment of PMjappropriate child adjustment PFjwhere j is an integer. To simplify Fig.2, the base 42 of the data in this example contains three pairs of maternal/child adjustment.
The storage device 36 represents the failure of the flash memory.
The system 28 also includes a processor 46, is capable of:
- pseudo-random way to select a virtual parent map CMEi,kmany E; cards in the base 38 of the data
- pseudo-random way to select the parent adjustment of PMjin the 42 data, and
and to generate the cryptogramfor the control word CWi,tgenerated gene is by ATOR 32, using the selected virtual parent map CMEi,kand selected maternal adjustment of PMj.
Moreover, the processor 46 can generate a message ECMi,tcontaining:
- formed the cryptogram,
- the ID of the virtual sub-card, which you should use to decrypt this cryptogram,
- child adjustment PFjassociated with the selected parent adjustment of PMjand
signature or cryptographic redundancy MAC (message authentication code) that is used to verify the integrity of messages ECM.
For example, processor 46 based on the programmable electronic computer. This computer is able to execute commands, recorded on the recording medium information to implement the method shown in Fig.5. For example, these commands are also recorded in the storage device 36.
Next, the integrated circuit 76 will be described with reference to Fig.3.
Integrated circuit 76 is more known as the SoC (system on chip). Here, the integrated circuit 76 preferably is a secure integrated circuit. The use of a secure integrated circuits is well known to specialists in this field. For receiving the Oia detailed descriptions of example, a secure integrated circuit you can refer to the application for the grant of a U.S. patent US 20050169468. Here, the integrated circuit 76 contains:
non-volatile storage device 90,
a volatile storage device 92, and
the processor 96.
The storage device 90 contains 100 data base (which is better seen in Fig.3A). This database 100 data associated with the identifier ICFEi,ksome child card CFEi,kthe cryptogramthis virtual child card CFEi,k. Each cryptogramcode virtual sub-map is obtained by encrypting the executable code virtual child card CFEi,kusing the key K_CFEi,k.
Preferably, for each virtual parent card ID ICMEi,kpreviously recorded in the storage device 36, there is at most one cryptogram codeassociated with this ID ICFEi,kand pre-recorded in the database 100. Thus emphasizes this feature of the invention, according to which the storage device 36 has such pre-recorded maternal card, for which there is no previously recorded in the database 100 of the cryptogram code associated virtual child card.
To simplify Fig.3A, the base 100 data contains only three cryptogram code virtualni the x child cards ,andassociated, respectively, with identifiers ICFE1,1ICFE1,2and ICFE1,2.
Here, the base 100 of the data does not contain cryptograms code virtual child cards,and.
All virtual sub-maps have a common structure. This structure is described below in detail with reference to Fig.4.
The storage device 90 also includes a base 102 data (better seen in Fig.3b). This database 102 data associated with channel i and ID ICFEi,kthe following:
key K_CFEi,kto decrypt the cryptogramvirtual child card CFEi,kand
key Ksign_CFEi,kto verify the authenticity of the virtual child card CFEi,k.
In this example, the base 102 data contains:
keys K_CFE1,1, K_CFE1,2, K_CFE1,3and
keys Ksign_CFE1,1, Ksign_CFE1,2and Ksign_CFE1,3.
The storage device 92 includes a table 104 (this is best seen in Fig.3C), associating the address of the virtual child card CFEi,krecorded in storage device 90, ID ICFEi,k. Such virtual child card CFEi,krecorded in storage device 90, preferably protected. The term "protected" in the estuaries and the ü refers to the fact that that executable codes virtual sub-maps are closed so that they cannot perform as they are. For example, a piece of executable code is encrypted to make impossible any attempt of engineering analysis. In this example, the table 104 is empty. This means that the table has no addresses protected virtual child cards, CFEi,k.
The processor 96 here is a programmable electronic computer. This processor 96 can execute commands, recorded on the recording medium information to implement the method shown in Fig.6. The processor 96 has a coprocessor 97 security. This coprocessor 97 are programmed for:
protection (hide, or, as in this case, encryption) of data stored in the storage device 92, and
recovery (in this case, decryption) of data segments stored in the storage device 92 in order to make them suitable for use by processor 96.
In this example, the coprocessor 97 contains non-volatile storage device write-once. This storage device 94 contains the key Kchipsuitable for the target device 10. This key, for example, etched in the manufacturing process of the integrated circuit 76.
Associate one with the other virtual is owned by the parent card 120 and virtual sub-map 122 will now be described with reference to Fig.4.
These virtual parent card 120 and virtual sub-map 122 are libraries of programs. Usually these virtual parent card 120 and virtual sub-map 122 represent the type library DLL (dynamically linked library) containing the appropriate executable codes.
Virtual parent card 120 contains:
operational key KexpEi,k,
algorithm 126 encryption, using the operational key KexpEi,kto encrypt the control word CWi,tand receiving the cryptogramand
constructor 128 syntax for formatting messages ECM and paste the cryptogram of the control word CWi,t, as well as other parameters (such as access) in the ECM messagei,tin this way, which is consistent with the constructor syntax associated with each virtual sub-map.
The specified encryption algorithm and the constructor syntax comprise code for execution by the processor 46.
In this example, the encryption algorithm contains a section 124 of the missed code. This plot 124 is designed to take into this place software correction for maternal card. In this example, this part 124 with the hat only one part of the algorithm 126, but not the entire algorithm 126.
Moreover, in the present description, the term "distinct virtual parent card" means two virtual cards, which differ from one another due to its working keys KexpEi,kand/or their algorithms 126 encryption and/or their designers 128 syntax.
Virtual sub-map 122 contains:
- working key KexpEi,k,
algorithm 130 decryption using the work key KexpEi,kto decrypt the cryptogramencrypted in the maternal map 120, and obtain the control word CWi,t,
analyzer 134 syntax to locate the cryptogramin a message ECMi,tand
signature of 136 to verify the integrity of virtual child card 122.
The decryption algorithm and the syntax analyzer comprise code for execution by the processor 96.
The term "different virtual sub card" means two virtual sub-maps, which differ from one another due to its working keys and/or its decryption algorithms and/or their parsers syntax.
The transfer method scrambled multimedia content in the system shown in Fig.1, now Boo the et described with reference to Fig.5. This method is implemented the same for each channel. Below we consider the transmission method for the case of channel 1.
At step 200, running in time t, the source 4 passes cryptoperiod CP1,tin the open form of the channel 1 in block 16 encoding. In this example, the duration of cryptoperiod is from five seconds to one minute. The length of the cryptogram is usually equal to 10 C.
At step 202 unit 16 performs encoding encoding CF1,tand transmits the encoded cryptoperiod in block 22 scrambling.
At step 204, the generator 32 selects the control word CW1,tand transmits this control word in the block 22 scrambling. More specifically, the generator 32 pseudorandom, selects the control word CW1,tand transmits this control word CW1,tin block 22 scrambling system 28.
At step 206 unit 22 performs scrambling, scrambling cryptoperiod CW1,tadopted at step 204. As a result, the block 22 scrambling generates the scrambled cryptoperiodThis block 22 scrambling transmits the scrambled cryptoperiodon the multiplexer 26.
At step 208, the system 28 generates various segments of the information needed to construct messages ECM1,t so this allows you to descrambler.html cryptoperiod.
More specifically, at step 210, the processor 46 selects the set E1parent cards, associated with channel 1, through the base 38 of the data. Then, in the 38 data he pseudorandom, selects a virtual parent map CM1,kfrom the set of virtual cards maternal CM1,1CM1,2and CM1,3in the structure of the set E1. For example, the processor 46 selects a virtual parent map CM1,1.
At step 212, the processor 46 pseudorandom, selects, in the 42 data maternal adjustment of PMjfrom the totality of the parent adjustments to the PM1PM2and PM3. For example, the controller 46 selects maternal adjustment of PM1.
At step 214, the processor 46 fills in the missing section 124 of the code as part of the algorithm 126 encryption virtual card CM1,1selected at step 210, maternal adjustment of PM1selected at step 211. The encryption algorithm is generated at this stage 214, hereinafter referred to as "the working algorithm of the encryption.
At step 216, the processor 46 generates a cryptogramwords CW1,tbased on:
- desktop encryption algorithm is generated at step 214, and
- working key KexpE1,1, soteriades who were selected maternal map CM E1,1,
- control word CW1,tcreated by the generator 32.
At step 217, the CPU 46 executes the constructor syntax in the virtual parent map CME1,1to determine the frame message ECM1,tthe position at which you want to insert the cryptogram.
At step 220, the system 28 generates a message ECM1,tcontaining:
ID ICFE1,1virtual parent card associated with the virtual parent card CME1,1,
- child adjustment PF1,
- the cryptogramthe control word CWi,tallowing descrambling cryptoperiod t channel 1, and
- cryptographic redundancy MAC.
At this stage 220, the system 28 puts the cryptogramon the frame message ECM1,tin the position found in step 217.
At step 222, the generator 28 transmits the message to the ECM1,tin the multiplexer 26.
At step 224, the multiplexer 26 provides multiplexing scrambled cryptoperiodformed at the step 206, and messages ECM1,ttransferred to step 222.
More specifically, the multiplexer 26 inserts the message ECM1,tin the signal before cryptoperiod CP1,t.
Steps 200 through 224 is repeated for each cryptoperiod Therefore, changing virtual parent map after each cryptoperiod.
The method of receiving scrambled multimedia content to the target device 10 will now be described with reference to Fig.6.
At the preliminary stage 300, the user terminal device 10 executes the subscription provider for media content. For example, the provider offers the possibility of viewing channels 1 and 2. More specifically, here, the user pays for the right to view only the channel 1 in the clear.
In response, the operator provides only the data necessary for the user to be able to descrambling information on channel 1.
At step 302, the device 6 encrypts virtual child card CFE1,1, CFE1,2and CFE1,3associated with the virtual cards maternal CME1,1CME1,2and CME1,3from the set E1, respectively, using the keys K_CFE1,1, K_CFE1,2and K_CFE1,3for more cryptograms,andcodes virtual child cards.
At step 304, the device 6 by means of one or more messages EMM, reports:
the IDs ICFE1,1ICFE,2 and ICFE1,3virtual child cards, CFE1,1, CFE1,2and CFE1,3,
keys K_CFE1,1, K_CFE1,2and K_CFE1,3to allow the target device 10 to decrypt the cryptogram,andand
keys Ksign_CFE1,1, Ksign_CFE1,2and Ksign_CFE1,3to allow the target device 10 to verify the authenticity of the virtual sub-card CFE1,1, CFE1,2and CFE1,3.
Keys K_CFE1,1, K_CFE1,2and K_CFE1,3and the keys Ksign_CFE1,1, Ksign_CFE1,2and Ksign_CFE1,3preferably pre-encrypt using a key Kchip.
At step 306 the target device 10 receives one or more messages EMM transmitted by the device 6, and pre-writes the contents of these one or more messages in the storage devices 90 and 92 to create a database 100, 102 of the data.
Base 100, 102 and data table 104 in the storage devices 90 and 92, as at the moment when the preliminary stage 300 is completed, as shown in Fig.3A, 3b and 3C.
At step 307, the user wishes to use multimedia content. For example, the user wants to watch a movie on channel 1 at time t.
To this end, at step 308 the target device 10 establishes a connection with the network 8 and adopts multi is lakirovannoe media content through its receiver 70. This multiplexed content demultiplexer through demultiplexer 72. Specified demultiplexer 72 transmits the scrambled cryptoperiodin block 74 diskriminirovaniya, and the message ECM1,ttransmits to the CPU 96.
You may recall that the ECM message1,tcontains:
ID ICFE1,1virtual child card CFE1,1,
- child adjustment PF1,
- the cryptogramand
- cryptographic redundancy MAC.
At step 309, the processor 96 checks the integrity of a received message ECM1,tthrough a new computing a cryptographic redundancy MAC for this message ECM1,tand comparing the obtained result with the cryptographic redundancy MAC contained in a received message ECM1,t. If the result of the calculation will coincide with the cryptographic redundancy MAC contained in a received message ECM1,tthen , the proposed method proceeds to step 310. Otherwise, the execution of this method is aborted.
At step 310, the processor 96 retrieves the ID of the ICFE1,1from a received message ECM1,t.
At step 312, the processor 96 looking at database 104 data using the received identifier ICFE1,1to determine whether there is already in the database Wirth the material subsidiary card CF E1,1to decrypt the cryptogramcontained in the ECM message1,f. If the base 104 data contains this virtual sub-map CFE1,1the proposed method proceeds directly to step 314. Indeed, in this case there is no need to decrypt the cryptogramto obtain this card, CFE1,1in the open form. If not, the operation goes to step 315.
At step 315, the processor 96 looking at base 100 data to determine whether this database identifier ICFE1,1. A positive response indicates that the target device contains a cryptogramand that, therefore, it is possible to represent this channel 1 on the display device.
Then, the processing proceeds to step 326.
If the base 104 of the data does not contain a cryptogramthen , the processor 96 can not decrypt the cryptogram. Thus, the user does not have permission to view channel 1 open, so that the execution of the method completes.
At step 326, the processor 96 decrypts the keys K_CFE1,1and Ksign_CFE1,1assosiated with ID ICFE1,1in the base 102 of the data using the key Kchip. Then, the processor 96 decrypts the cryptogramwith what emeniem key K_CF E1,1to obtain the decrypted virtual child card CFE1,1.
At step 328, the processor 96 checks the signature decrypted virtual child card CFE1,1using the key Ksign_CFE1,1. For example, the processor 96 applies a hashing function to the virtual map CFE1,1to obtain the first image of this map. He then decrypts the signature card 136 CFE1,1using public key Ksign_CFE1,1to obtain the second image. If the first and second images correspond to one another CF cardE1,1authenticated correctly.
In this case, at step 330, the processor 96 requests the storage device 92 to learn about the available memory space. If the storage device 92 has sufficient memory space decoded at step 326 virtual sub-map CFE1,1protect through coprocessor 97, copy in storage device 90, adding to the list in the database 104 data at step 332 and associated with the identifier ICME1,1. The term "inscribed in the list" means a transaction in which the memory address at which a copy of the virtual child card, associated with the identifier ICFE1,1in the base 104 of the data. If the space is small, at step 334 the storage device 92 removes one of the virtual card CFEi,kfrom the base 10, so you can take a virtual sub-map CFE1,1. For example, it uses the algorithm LRU (least recently used (LRU (least recent used)). The most recently used virtual sub-map in the storage device 90 is removed very first. Then virtual sub-map CFE1,1protect through coprocessor 97, copy in storage device 90 and, finally, enter in the list.
After step 332 or 334, the operation process moves to step 314.
If the signature is computed in step 328, does not match the signature contained in the virtual map, which is decoded at step 326, the virtual card CFE1,1not authenticated. In this case, the processor 96 is not decrypts the cryptogramand the admission process is aborted.
At step 314, the processor 96 executes a syntax analyzer of virtual child card CFE1,1and allocates the cryptogramand child adjustment PF1from the message ECM1,t.
At step 316, the processor 46 applies a subsidiary adjustment PF1allocated at step 314, the decryption algorithm in the virtual child card CF1,1. The decryption algorithm generated at step 316, hereinafter referred to as "the working decryption algorithm".
At step 318, the processor 96 rascher vivet the cryptogram use a working decryption algorithm generated at step 316, and a working key KexpE1,1contained in the virtual sub-map CFE1,1. Thus, in this step 318, the processor 96 receives the control word CW1,tin the open form.
At step 320, the processor 96 transmits a control word CW1,tin the open form in block 74 diskriminirovaniya.
At step 322, the block 74 diskriminirovaniya performs diskriminirovaniya scrambled cryptoperiodusing the control word CW1,tsubmitted by processor 96 and receives descrambling cryptoperiod CP1,t. This descrambling cryptoperiod CP1,tthen passed to the decoder 80.
At step 324, the decoder 80 performs decoding cryptogram CP1,tand then transmits the result of decoding the graphics card 82. This graphics card 82 then manages the representation of this result on the screen 86.
Steps 308 through 334 repeat for each cryptoperiod.
Possible other options.
For example, the parent map does not need to be pre-recorded in the storage device 36. This virtual parent map can be generated dynamically by the processor 46 at the preliminary stage 300 before they are transferred to associates in realnye child card.
In one embodiment, the process of selecting the target device 10 virtual child card to use in order to decrypt the cryptogramcontains dynamic generation of virtual card processor 96 on the basis of functions, pre-recorded in the storage device 90, and the received identifier ICFEi,k.
In another embodiment, the syntax of messages ECM are always the same. In this case, the virtual maternal and child maps contain, respectively, is always the same constructor syntax and the same syntax analyzer.
Again, in one embodiment, maternal and child adjustment may be applied, respectively, to the codes constructor syntax and syntax analyzer in the virtual cards.
In one embodiment, virtual maternal card or many Eivirtual maternal maps of the present invention associates a special group of the parent adjustments, appropriate only to this map or this many Ei.
Again as one of the variants of the parent and/or child adjustment retain directly in the virtual maternal and child cards, respectively.
Again as one of the variants, maternal and child adjustment may b shall be excluded. In this case, the encryption and decryption in the virtual maternal and child cards no longer contain any sections 124 and 132 of the missed code.
In another embodiment, there is no set Eivirtual maternal cards that are specific for the considered channel i. For example, there is a single set for all channels. In this case, all virtual cards from this set can be used to encrypt the control word applied to encrypt cryptoperiod on one channel i. Preferably, in order to restrict access to certain channels to only those users who have the appropriate access rights, access conditions include messages ECM sent by the device 6. These access rights are compared to the access rights recorded in the virtual sub-map, while receiving messages ECM to determine whether the processor to decrypt the cryptogram, is included in this message ECM.
In another embodiment, the processor of the security system that implements the method shown in Fig.5 or 6, is a processor comprising a microprocessor card.
In one embodiment, the messages ECM not contain the ID of the ICF a particular virtual child card, and the ID of the multiple virtual child cards. With what you learn when the receiving terminal receives a message ECM is the target device tries all virtual sub-map associated with this set until it finds a virtual child card to decrypt the cryptogram CW* contained in the message ECM.
In another embodiment, the target device does not transmit the ID of the new virtual sub-card, you will need to use. For example, in this case, the target device whenever it receives a new cryptogramchecks whether the currently selected virtual sub-map to accurately decipher the cryptogram. In case of positive response, the target device continues to use the same virtual sub-map. If the answer is negative, the target device successively tries all virtual child cards, which he has in memory until you find the card that will allow you to decipher the cryptogram. This virtual sub map then chosen to be used instead of the previous card.
In one embodiment, at step 300 virtual child card not pass through messages EMM, and on the special channel part of the signal is broadcast (i.e., broadcast to all target device connected to the network 8) Il the multicast (i.e., broadcast to a specific group of target devices connected to the network 8), such as DVB-SSU or DSM-CC, or again through messages ECM.
If the network 8 is a hybrid communication network (e.g. the network 8 connection established by the network, TNT and the Internet), the device 6 can transmit the target device URL (uniform resource locator) of the server virtual child cards. Each target device downloads the virtual sub-maps from this server. Preferably, the procedure of downloading virtual child cards protected. For example, it is recommended to use SSL (secure shell) or HTTPS (secure hypertext transfer information) and/or to use the public key infrastructure (better known as PKI). This option can be implemented using a system that uses Internet TV, such as IPTV or WebTV.
For term limits the applicability of virtual child cards in each card can be included to specify the duration of the period of validity.
According to the method shown in Fig.5, in one embodiment, the same virtual parent card remains valid for several cryptoperiod, and maternal adjustment changes in each cryptoperiod.
In another embodiment of this method in each novacapitalis only change the virtual parent map, but remains the same parent adjustment.
Preferably, the virtual parent card is changed at least every 30 minutes, or at least every 10 minutes, or even more preferably at least every minute.
1. Method of transmitting and receiving multimedia content, each cryptoperiod CPtwhich is scrambled using the appropriate control word CWtwhen this method contains the steps are:
encrypt using the transmitter control word CWtusing the working key and the executable code of the encryption algorithm contained in the virtual parent map, to obtain the cryptogram
generate a message ECM (message control rights), containing the cryptogram
take with a target device message ECM, determine the location of the cryptogram
perform diskriminirovaniya of cryptoperiod CPtscrambled multimedia content using the decrypted control word CWt.
the method further comprises the steps are:
perform transmitter, at least every two hours, changing the virtual parent card used to obtain the cryptogram
perform with the target device in response to this change, select the new virtual child card to use when decrypting the cryptogram
2. The method according to p. 1, in which a new used virtual parent map differs from the previously used virtual parent map executable code of the decryption algorithm and the constructor syntax.
3. The way to generate messages ECM to implement the method of transmitting and receiving multimedia content under item 1, in which each message ECM contains a cryptogram
perform encryption of the control word CWtusing the working key and the executable code of the encryption algorithm contained in the virtual parent map, to obtain the cryptogram
generate a message ECM containing the cryptogram
while this method further comprises a stage on which:
perform transmitter, at least every two hours, changing the virtual parent card used to obtain the cryptogram
4. The method according to p. 3, additionally containing phase, which is passed to the target device, in a message ECM, the ID of the virtual sub-maps to be used for decryption of the cryptogram
5. The method according to p. 3, in which the runtime change of virtualni the th parent card contains step, which select the virtual parent map from the set of virtual cards, pre-recorded in the transmitter, virtual cards belonging to different from one another.
6. The method according to p. 5, in which the step of changing the virtual parent card contains step, which selects the parent map pseudo-random manner from a set of virtual cards, pre-recorded in the transmitter.
7. The method according to p. 3, further comprising stages, which are:
choose a set of many different virtual maternal cards from multiple sets of virtual maternal cards, depending on the multimedia content to be scrambled, using ratios associated with each multimedia content is only one set of virtual maternal cards, with each virtual parent card belongs to only one set, and
encrypt the control word for scrambling media content exclusively through virtual parent card selected from a specified set associated with the specified content to restrict access to the scrambled media content exclusively receiving terminal devices having a set of virtual child cards that meet the speaker specified set of virtual maternal cards.
8. The way of reception by the terminal device to implement a method of transmitting and receiving under item 1, the method includes the steps are:
receive, via one or more messages ECM, the cryptogram
determine the location of the cryptogram
while this method further comprises the steps are:
selected via the target device, in response to changes in the virtual parent card on the transmitter, a new virtual sub-map to be used for decryption of the cryptogram
9. The method according to p. 8, further comprising stages, which are:
take the ID of the virtual sub-cards at the stage of admission of the cryptogram, and
choose using the target device virtual sub-map from a set of pre-recorded cards based on the identifier received from the reception phase of the cryptogram.
10. The method according to p. 8, further comprising stages, which are:
take with the target device, at the stage of receiving the cryptogram, one or more additional commands, and
modify the Executive code of the selected virtual sub-maps by adding and/or replacing only one piece of commands executable code of the specified virtual card on child adopted by a team or teams, in response to receiving one or more additional commands.
11. The method according to p. 9, further comprising stages, which are:
take the up with the target device encrypted virtual child map,
retain adopted encrypted virtual child map, to add the specified map to a set of pre-recorded virtual child cards, and
decrypts the specified encrypted virtual sub-map in response to receiving the identifier, while
the stages of receiving, storing and decoding the specified child encrypted card to perform the implementation steps of receiving the cryptogram and select new virtual sub-map.
12. The recording medium information contains commands, which, when executed by an electronic computer, the execution of the method according to any of paragraphs.1-11.
13. A transmitter to perform a method of generating messages ECM according to any one of paragraphs.3-7, containing:
block scrambling (22), made with the possibility of scrambling the corresponding cryptoperiod CPtmultimedia content using the control word CWt,
encryption of the control word CWtusing the working key and the executable code of the encryption algorithm contained in the virtual parent map, to obtain the cryptogram
when you do this:
system (28) is programmed with the ability to change the virtual parent card at least every two hours, to obtain a cryptogram
14. The receiving terminal device for implementing the method according to any one of paragraphs.8-11, containing:
set (100, 104) pre-recorded virtual child cards,
the receiver (70) which has a capability of receiving, using one or more messages ECM, cryptogram
an integrated circuit (76), programmed for:
determine the location of the cryptogram
diskriminirovaniya of cryptoperiod CPtthe multimedia content scrambled by means of the decrypted control word CWtwhile
integrated circuit (76) is additionally programmed to select, in response to changes in the virtual parent card, via the transmitter, a new virtual sub-maps to be used for decryption of the cryptogram
FIELD: radio engineering, communication.
SUBSTANCE: invention relates to a broadcast encryption method. The technical result is achieved through a method of controlling decoders of at least one group of decoders, having access to audiovisual data, wherein the method comprises the following steps: at a step when the decoder should become a member of a group: obtaining and storing keys relating to a certain position in the group according to the broadcast encryption scheme; obtaining and storing current group access data containing at least the current group access key which is common for said group at the step of accessing the audiovisual data: using the current group access data for direct or indirect access to audiovisual data, at the step of updating the current group access key: transmitting a first group message containing at least the next group access data containing at least the next group access key encrypted such that only uncancelled decoders can gain access thereto, wherein said group message is further encrypted by the current group access key (CGK); updating the current group access key using the next group access key.
EFFECT: high efficiency of controlling access to broadcast content for a large number of subscribers by controlling access only based on keys.
5 cl, 4 dwg
FIELD: physics, computer engineering.
SUBSTANCE: invention relates to computer engineering. The invention can be implemented in a conditional access content broadcast system where it is desirable to identify and take measures against receiving equipment, applied when sharing control words. Owing to the requirement that receiving equipment used in the system transmits to a transmission station a conditional access content message at a precisely defined time, the invention provides a method through which a server identifies receiving equipment participating in the sharing of control words and prevents said receiver from further accessing said content.
EFFECT: effective protection of transmitted content.
12 cl, 2 dwg
FIELD: physics, computer engineering.
SUBSTANCE: invention relates to cryptography. A chipset function activation method includes: receiving at least one of the following elements: a segmentation key, a general purpose key and a global cryptographic algorithm selector; transmitting at least two of the following elements: an initial value, the obtained segmentation key, the general purpose key and the global cryptographic algorithm selector to a computation module, wherein the initial value, the obtained segmentation key, the general purpose key and the global cryptographic algorithm selector are provided by at least two different organisations; generating in the computation module a temporary key using one of the following elements: at least one cryptographic algorithm of the computation module and at least two elements selected from a group including the initial value, the segmentation key, the general purpose key and the global cryptographic algorithm selector; receiving an activation message using the computation module; receiving an authentication code of said message using the computation module, wherein said message authentication code is calculated using the temporary key; authenticating said received message using the message authentication code and the temporary key; if the received message is authentic, activating the corresponding chipset function; if the received message is not authentic, prohibiting activation of said corresponding chipset function.
EFFECT: effective chipset protection.
11 cl, 1 dwg
FIELD: physics, computer engineering.
SUBSTANCE: invention relates to information decryption methods. The method comprises steps of, in response to the absence in any of the terminals of one or more control words CWc for decrypting one or more multimedia content cryptoperiods, transmitting through said terminal to a control word server a request containing a cryptogram(s) of said one or more absent control words, and in response, transmitting by the control word server to said terminal said one or more absent control words, wherein the control word server selectively determines for each terminal the number of additional control words CWs intended for transmission to the terminal depending on the probability of compromising the protection of said additional control words, and besides the absent control words CWc, transmitting to said terminal said determined number of additional control words CWs, which enables the terminal to decrypt additional multimedia content cryptoperiods in addition to cryptoperiods decrypted using the requested absent control words CWc.
EFFECT: ensuring secure transmission of control words.
10 cl, 6 dwg
FIELD: radio engineering, communication.
SUBSTANCE: apparatus comprises: a unit which stores a key used for encrypting or decrypting data; a unit which receives a key transmission request including a key-dividing number via a wireless signal from an operation terminal; a unit which acquires a key transmission request from the wireless signal received by the reception section; a unit which determines a security level when transmitting the key to the operation terminal, as a transmission security level; a unit which determines a transmission power in accordance with the transmission security level determined by the security level determination unit and the key-dividing number included in the key transmission request acquired by the key transmission request acquisition unit; a unit which acquires each key fragment by dividing the key stored in the storage unit into the key-dividing number; and a unit which transmits the each key fragment acquired by the key acquisition unit using the transmission power determined by the transmission power determination unit, via a wireless signal to the operation terminal.
EFFECT: safer data transmission.
15 cl, 9 dwg
FIELD: physics, computer engineering.
SUBSTANCE: invention relates to a network operation method. A network comprises a node and a system control device. A system control device comprises a root key material which is a set of functions, each having a degree of complexity α, and a node is provided with a portion of key material of a node having a degree of complexity α extracted from the root key material. The system control device generates a portion of key material for an external user with a degree of complexity α from the root key material and generates an access identifier. The system control device generates access key material with a degree of complexity less than α from the portion of key material for the external user and generates a node identifier. The system control device provides the external user with a portion of access key material and the node identifier. The external user extracts a key from the portion of access key material and sends to the node said key and access identifier. The node calculates a key from the access identifier and the portion of node key material and compares the key sent by the external user and the key calculated by the node in order to identify the external user.
EFFECT: improved security.
14 cl, 4 dwg
FIELD: physics, computer engineering.
SUBSTANCE: invention relates to methods of providing secure communication in a network. The method comprises: an administration device provided with root keying materials, and steps of: generating, by the administration device based on the root keying materials, parts of keying material of a first node containing a certain number of sub-elements, and parts of keying material of the first node, assembled for generating a first terminated key, the administration device selects a subset of sub-elements of the first parts of the keying material, wherein the number of selected sub-elements is less than or equal to the total number of sub-elements of the first parts of the keying material, and the selected sub-elements form partial parts of the keying material of the first node or a symmetrical key generation mechanism, the first node generates, based on the symmetrical key generation mechanism of the first node and on a second node identifier, a first key used to provide secure communication with a second node.
EFFECT: more secure data transmission in a network.
6 cl, 7 dwg
FIELD: physics, computer engineering.
SUBSTANCE: invention relates to computer engineering and specifically to means of secure communication in a network. The method relates to secure transmission of information from a first node (N1) to a second node (N2) in a network, the first node comprising a first node keying material (KM(ID1)), the second node comprising a second node keying material (KM(ID2)), wherein the keying materials of the first node and of the second node comprise each a plurality of shared keying root parts formed by segments of the shared keying root parts. A communication network, having at least two communication devices, carries out said method.
EFFECT: safer communication by dividing keys into segments for predistributed keying material according to a variable distribution.
13 cl, 5 dwg
FIELD: physics, computer engineering.
SUBSTANCE: invention relates to computer engineering. A method of controlling access to a set of channels using a receiver/decoder comprising a security module (SC), each channel being encrypted by a specific channel control word (CW1, CW2), each channel having a channel identifier and transmitting access control messages ECM containing at least the current channel control word and the channel access conditions. The method comprises the following steps: tuning to a first channel having a first channel identifier (ID1); transmitting the ID1 to the SC; receiving first access control messages ECM1 containing a first control word (CW1); transmitting the first access control messages ECM1 to the SC; decrypting the first access control messages ECM1 and verifying the channel access conditions; if the access conditions are met; transmitting the CW1 to the receiver/decoder; storing of the CW1 and the ID1 in the SC; tuning to a second channel having a second channel identifier ID2; transmitting the ID2 to the SC; calculating, by the SC, the second control word (CW2) by performing the following steps: calculating a root control word (RK) with an inverse cryptographic function F-1 using the CW1 and the ID1; calculating the CW2 with the cryptographic function F using the RK and the ID2; transmitting the CW2 to the receiver/decoder.
EFFECT: reducing channel switching time when a user selects another channel.
9 cl, 3 dwg
FIELD: radio engineering, communication.
SUBSTANCE: invention relates to distribution of a cryptographic secret key between a transmitting side and a receiving side. An apparatus for secure reception and transmission of data comprises a key generation controller and a unit for providing the number of iterations.
EFFECT: facilitating automatic control of security and latency for generating a cryptographic secret key by setting a number of iterations, based on which the number of messages to be exchanged while generating the cryptographic secret key is controlled.
11 cl, 17 dwg
FIELD: communication systems.
SUBSTANCE: system has receiver, transmitter, processing element, connected to receiver and transmitter and controlling receiver and transmitter, digital rights module, connected to processing elements and controlling operation of communication device in digital rights environment on domain basis, while digital rights module of communication device together with dispenser of domains of digital rights environment on domain basis is made with possible selective addition of communication device to domain, owning one or several communication devices, which together use a cryptographic key.
EFFECT: possible selective retrieval and decoding of digital content on basis of membership in a domain.
10 cl, 11 dwg
FIELD: data transfer technologies.
SUBSTANCE: device which should be transmission destination, is authenticated, and if device is not authorized, then encrypted data, read from memorizing device, are decoded to produce decoded data, which are then encrypted again on basis of data of specific device key, received from device, which should be transmission destination for receiving re-encrypted data. Re-encrypted data are then transferred to device, which should be transmission destination.
EFFECT: forbidden unauthorized copying of data.
8 cl, 13 dwg
FIELD: electric communications and computer engineering, in particular, methods and devices for cryptographic transformation of data.
SUBSTANCE: the essence of method is in generation of binary vector, appropriate for date and time of discontinuous message transfer, generation of binary vector of secret parameter, generator of binary identification vector and addition thereof to discontinuous message. Message is different from known methods because it includes additionally forming a random binary vector and binary vector of protection key, while binary vector of secret parameter is formed by double compressing of random binary vector, while binary identification vector is formed by transformation in circle of residue class by module p of binary vector, appropriate for data and time of transfer of discontinuous message and binary vector of secret parameter.
EFFECT: rejection of false messages, increased speed of process of confirming authenticity of discontinuous message.
FIELD: ciphering key transmission methods and systems.
SUBSTANCE: according to proposed method same information Kc is afforded for more than one receivers 1 pertaining to receiver group G; each receiver saves SAi information unambiguously assigned to the latter. Kc information is determined by expression Kc = f(K,biSAi), where f is desired function; K is information common to all receivers; b1 is information different for each receiver and for each value of information K. Each receiver is given access to information b1 prior to submitting information Kc. Information K is transferred to all receivers directly prior to submitting information Kc so that each receiver can calculate the latter using mentioned expression.
EFFECT: simplified design and enhanced response of system to piratical cards.
13 cl, 2 dwg
FIELD: data transmission.
SUBSTANCE: in accordance to the invention, data of content of input digital data is encrypted on basis of data of first key, which is then encrypted on basis of function, generated on basis of a random number, and data of second key, generated with usage of data of specific key of device and common key data. During decoding, encoded data is received, consisting of encrypted content data, encrypted first key data, random number and common key data, second key data is generated on basis of specific device key data and common key data, encrypted first key data is decoded on basis of generated second key data and function, generated on basis of random number, encrypted content data is decoded on basis of decoded data of first key.
EFFECT: unauthorized data copying is prevented.
2 cl, 13 dwg
FIELD: data transfer.
SUBSTANCE: in accordance to the invention, digital data are decoded, which are encrypted on basis of specific device key data, which is supposed to be transmission destination, data is extracted from decoded encrypted data, which is related to copying conditions, and recording of decoded encrypted data into recording device is performed on basis of extracted data, related to copy allowing conditions.
EFFECT: prevented unauthorized copying of data.
2 cl, 12 dwg
FIELD: information encryption.
SUBSTANCE: method includes forming quantum photonic status sequence on the transmitting station to encode encryption keys and transmission of these statuses via open space to receiving station; at that, the distance between the stations is previously measured and clock on both station is synchronised; then, transmitting station converts quantum photonic statuses to one- or multiphoton orthogonal statuses and measures their sending time, which is sent to receiving station; the receiving station measures receiving time of the one- or multiphotonic quantised statuses, determines delay value, using which decoding and eavesdropping are performed.
EFFECT: provision of encryption key security during its long-distance transmission via open space, provision of long-term stability and reducing error stream in transmitted encryption keys on receiving station.
3 dwg, 2 tbl
FIELD: information technology.
SUBSTANCE: system and the method of information protection in computer networks based on key distribution, includes numerous units and a trust centre (TC). All the units are connected with one another and with the TC by communication channels. Each unit of the network and the TC has executive processor circuit as well as memory. TC includes the pseudo-random number generator designed to generate long-term keys, key blocks, primary incidence sub-matrix of lower size for building the incidence matrix (IM) of the required size; to form half-weight columns with the required number of binary bits for building the IM of the required size on the basis of the primary lower-size sub-matrix, with the extension capacity of the IM depending on the number of the network units communicating to one another to transfer the formed key blocks to the network units involved in the data exchange process through the communication channels. One key block corresponds to each unit; the processor executive circuits of the network units form the common secret key in order to ensure confidentiality while exchanging information between the units.
EFFECT: simplification of the key distribution method.
10 cl, 2 dwg
FIELD: information systems.
SUBSTANCE: invention refers to the data processing systems and, particularly, to the methods and devices providing cryptographic protection in the data processing system. The broadcasting key, renewed through a long lapse of time, is encrypted using a registration key and is periodically supplied to a user. The key with a short-time renewal is encrypted using the broadcasting key. The short-time key is available with each broadcasting message, thereat the information, sufficient for calculating the short-time key, is provided in the internet protocol header preceding to the broadcasting content. The broadcasting messages are then encrypted using the short-time key, thereat the user encrypts a broadcasting message using this short-time key.
EFFECT: creation of protected and efficient method of keys renewal in the data processing system.
24 cl, 30 dwg
FIELD: information technologies.
SUBSTANCE: invention refers to data transmission, specifically to effective cryptographic data transmission in real-time security protocol. Transmitting terminal can be used for data decoding with session key received from bitstream. Bitstream can be transmitted with head information to transmitting terminal. To maintain bandwidth the information can be divided into parts, and each part is transmitted with encrypted data package. Transmitting terminal can be used for restoration of bitstream from information parts comprising package headers, and use of bitstream for session key receiving. Session key can be used for data decoding.
EFFECT: higher cryptographic security of transferred data.
24 cl, 6 dwg