EP1861984A1 - Procédé pour la transmission sécurisée de données utiles - Google Patents

Procédé pour la transmission sécurisée de données utiles

Info

Publication number
EP1861984A1
EP1861984A1 EP07704439A EP07704439A EP1861984A1 EP 1861984 A1 EP1861984 A1 EP 1861984A1 EP 07704439 A EP07704439 A EP 07704439A EP 07704439 A EP07704439 A EP 07704439A EP 1861984 A1 EP1861984 A1 EP 1861984A1
Authority
EP
European Patent Office
Prior art keywords
connection
direct connection
communication device
encryption
gwl
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP07704439A
Other languages
German (de)
English (en)
Inventor
Thomas Stach
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Priority to EP07704439A priority Critical patent/EP1861984A1/fr
Publication of EP1861984A1 publication Critical patent/EP1861984A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/04—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks
    • H04L63/0428—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload
    • H04L63/0485—Networking architectures for enhanced packet encryption processing, e.g. offloading of IPsec packet processing or efficient security association look-up
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/20—Network architectures or network communication protocols for network security for managing network security; network security policies in general
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/10—Architectures or entities
    • H04L65/102—Gateways
    • H04L65/1043—Gateway controllers, e.g. media gateway control protocol [MGCP] controllers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/1066—Session management
    • H04L65/1069—Session establishment or de-establishment

Definitions

  • the invention relates to a method for transmitting user data between a first communication device using encryption and a second communication device.
  • VoIP Voice / Video over Internet Protocol
  • VoIP communication often involves several different communication networks.
  • the different commu ⁇ nikationsnetze are usually coupled by so-called gateway devices together that perform a conversion of the as part of the VoIP communication data to be transmitted when it passes between the communication networks.
  • Such implementations generally adversely affect the transmitted voice or video quality.
  • a Nutz Schemedirekteur can be bypassed by the gateway devices at least logically.
  • Such a construction of a direct connection is also known as "Direct Media Connection".
  • the first communication device for transmitting user data between a first communication device using encryption and a second communication device, the first communication device is caused to transmit a direct connection setup message as well as an encryption message in the direction of the second communication device.
  • the direct connection setup message is transmitted with a first direct connection address, for example an IP address, which identifies an encryption device.
  • the encryption message is transmitted with ei ⁇ ner the first communication device identifying, second direct connection address, for example, an IP address.
  • the first and / or the second communication ⁇ tion device can, for example, by a terminal, a personal computer, a so-called IP phone, a
  • Switching device or a switching device with connected terminal be realized. If it is determined by the transmitted encryption message, that the second communication device supports the specified encryption, a direct connection between the second and the first communication device is established on the basis of the second direct connection address. The user data is then transmitted in encrypted form via the established direct connection. If this determination is not made, a direct connection is established between the second communication device and the encryption device on the basis of the first direct connection address. About the established direct connection, the user data is transmitted to the encryption device and forwarded by this encrypted to the first communication device.
  • the invention allows flexible communication between communication devices having different encryption requirements and capabilities with the advantage of using direct connections.
  • the inventive method is backwards compatible in that, if the second communication device does not have the corresponding encryption capability, it must not be able to recognize or interpret the encryption message in order to obtain the first direct connection address required for communication with the encrypting first communication device as the destination address , Since the first direct connection address identifying the encryption device is included in the direct connection setup message, existing non-encrypting but directly connectable communication devices that usually ignore the encryption message may continue to be used with the invention without modification.
  • the transmission of the direct connection setup message as well as the encryption message can be carried out within the framework of a structure of a first connection setup message. Connection between the first or second communication device done. Such an initial connection is often referred to as a master call. As a direct connection can accordingly such a master call within egg ner "Direct Media Connection" associated slave call up ⁇ be built.
  • the first connection can be established as a conventional call, for example by means of a destination call number, from the first to the second communication device.
  • the first connection can be established by means of a connection control and run via one or more gateway devices and via different networks.
  • authoritative connection data can be transmitted with the direct connection setup message and the encryption message for the establishment of the direct connection, whereby the communication devices can establish the direct connection, bypassing the gateway device. If the second communication device supports the specified encryption, the direct connection can be established directly between the two communication devices.
  • the encryption device can be implemented in the gateway device. This is advantageous insofar as the encryption device for forwarding the direct connection can directly access connection data present in the gateway device via the first connection.
  • the direct connection can be assigned to the first connection, the assignment being stored in the encryption device.
  • the encryption device can determine the first communication device as an end point, the first connection assigned to the direct connection, and useful data arriving via this direct connection to the end point thus determined, namely the first communication device. tion, forward.
  • the encryption device can derive essential connection data from connection data of the first connection for forwarding the direct connection.
  • the initial connection may remain parallel to Di ⁇ rekttress so that the payload data as required by the direct connection to the first connection and / or vice versa.
  • Figure 1 shows a communication system with different encryption requirements having communication facilities
  • Figure 2 shows the communication system in a communication between communication devices with different encryption requirements
  • FIG. 1 shows a schematic representation of a communication system with different communication devices Ul, Cl, Sl, U2, C2 and S2, which are connected via different gateways GW1 and GW2 coupled networks (not explicitly shown).
  • the communication system is assumed in the present embodiment as IP-based (IP: Internet Protocol).
  • IP Internet Protocol
  • PBX Primaryvate Branch Exchange
  • Both gateways GW1 and GW2 are coupled to a call controller CC, which also includes a direct connection controller.
  • call control is often referred to as "call control” and such a direct connection control as “DMC control” (DMC: Direct Media Connection).
  • the communication equipments Ul, Cl, Sl, U2, C2 and S2 different closures ⁇ lung requirements and have encryption capabilities.
  • the communication devices Ul and U2 can not perform voice encryption, that the communication devices C1 and C2 can transmit and receive both encrypted and unencrypted voice data, and that the communication devices S1 and S2 are protected in that they only encrypt encrypted voice data send and receive.
  • the communication system uses the Direct Media Connection method to optimize the voice quality of a VoIP call.
  • two separate but correlated with one another and with each other arranged conces- connections are set up, consisting parallel ben ⁇ lead.
  • a so-called master connection is established, which is used to basically establish the VoIP call.
  • the master connection initiates a setup of the second connection as a so-called slave connection (slave call), by means of which a direct user data connection is established between the VoIP connection partners.
  • the master connection is preferably a conventional call, which is distinguished by a conventional telephone number is established for each called communication device.
  • Figure 1 illustrates a structure of master and slave connections between communication devices with the same encryption requirements and capabilities, that is, a communication between the communication devices Ul and U2, between the communication devices Cl and C2 and a communication between the communication devices Sl and S2.
  • the call control CC and the gateway GW2 ge ⁇ is lead.
  • the user data of the master connection is routed via the same route.
  • the signaling is illustrated in FIG. 1 by solid lines, the useful data transmission of the master connection by dashed lines.
  • the call control CC is controlled by the master connection.
  • the network components GW1, CC and GW2 can also be arranged several times in heterogeneous communication systems, for example GW1-CC-GW2-... GW (N1) -CC (NI) -GW (N).
  • the voice data to be transmitted in at least one or all of the transit gateways in each case undergo a conversion and / or transcoding, which adversely affects the voice quality.
  • the slave connection is established in parallel as a direct connection with existing master connection, in which the voice data directly between the calling communication device Ul, Cl or Sl and the called communication device U2, C2 or S2 can be transmitted.
  • the IP addresses of the respective connection partner are Exchange of the master connection.
  • the IP addresses are transmitted within direct connection setup messages, for example so-called DMC messages.
  • the communication device U1 transmits a direct connection setup message DMC_U with its IP address to the communication device U2.
  • the communication device Cl a direct connection setup message DCM_C with its IP address to the communication device C2 and the communication device Sl a direct connection setup message DMC with its IP address to the communication device S2.
  • the direct connection setup messages DMC_U, DMC_C and DMC thus contain, in the case of communication between communication devices having the same encryption requirements, in each case the IP address to which the respective receiver of this IP address can transmit voice data directly.
  • Such direct connection setup messages can usually be correctly interpreted by both existing communication devices with encryption as well as existing communication devices without encryption capabilities.
  • FIG. 1 illustrates a transmission of the encryption message CRM_C from the communication device C1 via the gateway GW1, the call control CC and the gateway GW2 to the communication device C2 and a transmission of the encryption message CRM from the communication device S1 via the gateway GW1, the call controller CC and the gateway GW2 to the communication device S2.
  • the encryption message CRM_C indicates the encryption capabilities and encryption requirements of the communication device Cl
  • the encryption message CRM indicates the encryption capabilities and encryption requirements. ments of the communication device Sl.
  • With reference to the encryption message CRM CRM_C or their respective receiver can determine if its encryption capabilities address the encryption requirements specified in each unloading, if this is the case, establish a corresponding ver ⁇ encrypted slave direct connection.
  • the slave connections illustrated by FIG. 1 are constructed directly between the respective communication partners U1 and U2, C1 and C2 or S1 and S2 under at least logical bypassing of both gateways GW1 and GW2.
  • a logical bypass may e.g. can be realized by means of a via the gateways GWL and / or GW2 running tunnel connection, by which a user data conversion in GWl and / or GW2 is avoided.
  • the signaling of a respective slave connection is illustrated in FIG. 1 by solid lines, the user data transmission by dot-dash lines.
  • Figure 2 shows a schematic representation of the communication system shown in Figure 1 in a communication between communication devices with different encryption requirements and encryption capabilities. Identical reference numbers have the same meaning in Figure 2 as in Figure 1.
  • Figure 2 illustrates an exemplary waveform of Nutzda ⁇ tentagenen emanating from the only communicating encrypted communication device Sl.
  • a first payload data connection between the communication devices S1 and S2 a second payload data connection between the communication devices S1 and C2, and a third payload data connection will be described concretely below considered between the communication devices Sl and U2.
  • the communication device S1 can exchange the user data directly encrypted.
  • the payload data connection between Sl and U2 this is not readily possible because the communication device S2 may only send and receive encrypted, but the communication device U2 has no encryption capabilities.
  • this is done via the gateway GWL in which a ⁇ closures averaging module CR is integrated for encryption and decryption of voice data.
  • the gateway acts GWL consequently as Locks ⁇ selungs pain.
  • a direct connection setup message DMC and an encryption message CRM from the calling communication device S1 are used respective call destination S2, C2 and U2 transmitted.
  • the established master connections extend in accordance with the above statements from the calling communication device S1 via the gateway GW1, the call control CC and the gateway GW2 to the respective call destination S2, C2 or U2.
  • the direct connection setup message DMC comprises a direct connection address IP_GWl, which identifies and addresses the gateway GW1 functioning as the encryption device.
  • the direct connection address IP_GW1 is inserted into the direct connection setup message DMC such as an address addressing the calling endpoint of the direct connection to be established.
  • the encryption message CRM comprises a direct connection address IP_S1 identifying and addressing the calling communication device S1.
  • the direct Connection address IP_GWl an IP address of the gateway GWL and the direct connection address IP_S1 an IP address of the communication device Sl.
  • the IP address of the gateway GW1 is entered in the direct connection setup message DMC, because at the beginning of the call establishment it is not yet known which encryption capabilities the respective called communication device S2, C2 or U2 has and because the gateway GWL encryption and Ent ⁇ encryption, so to speak on behalf of a non-encryption-capable communication device, can make here U2.
  • the communication device Sl can also establish encrypted direct connections to encryptable communication devices, here C2 and S2, the IP address IP_S1 is transmitted as the second IP address with the encryption message CRM.
  • Communication devices C2 and S2 unlike the communication device U2, can recognize and process the received encryption message CRM.
  • the communication devices C2 and S2 can first check, on the basis of the encryption message CRM, whether they satisfy the encryption requirements of the communication device S1. If this as in the present Embodiment is the case, the communication ⁇ can facilities C2 and S2, discard the direct connection address IP_GWl contained in the direct-connect setup message DMC and instead, the direct connection address contained in the encryption message CRM IP_1 use to the construction of an encrypted slave direct connection between C2 and Sl or S2 and Sl to cause.
  • the communication device C2 or S2 using the encryption message CRM would determine that it did not satisfy the encryption requirements of the communication device S1, the communication device C2 or S2 could use the direct connection address IP_GW1 contained in the direct connection setup message DMC. On the basis of this, an unencrypted slave connection could be established to the gateway GW1 acting as the encryption device, which could continue this slave connection in encrypted form to the communication device S1.
  • the encrypted slave direct connections between the communication devices Sl and S2 and Sl and C2 are each angedeu ⁇ tet by dotted double arrows. Unlike the underlying master connections, the two slave direct connections bypass the gateways GW1 and GW2 as well as the call control CC at least logically.
  • the communication device U2 has no encryption capabilities and as a result can not recognize or interpret the encryption message CRM.
  • the direct connection setup message DMC can be recognized and evaluated by the communication device U2. Since the IP address IP_GWl of the gateway GW1 is contained in the direct connection setup message DMC as a direct connection address, this is interpreted by the communication device U2 as the end point of the slave direct connection to be set up and consequently an unencrypted slave direct connection between the communication cation device U2 and the gateway identified by the IP address IP_GWl.
  • the unencrypted slave direct connection is indicated in FIG. 2 by a dashed double arrow.
  • this slave connection at least logically bypasses the gateway GW2 and possibly further intermediate transit gateways and thus avoids multiple quality-reducing conversions of the voice data in relation to connections which all gateways pass through.
  • the gateway GW1 encrypts the voice data arriving via the slave direct connection from the communication device U2 by means of the encryption module CR and transmits the voice data in encrypted form via a continuation of the slave direct connection from the gateway GW1 to the communication device S1.
  • the encrypted continuation of the slave direct connection between the gateway GW1 and the communication device S1 is indicated in FIG. 2 by a dot-dashed double arrow.
  • the gateway GW1 determines the actual end point, here Sl, of the slave direct connection arriving from the communication device U2 in that the master connection assigned to this slave connection is determined and the slave connection to the end point of the master connection, here Sl, knows - is carried out.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Computing Systems (AREA)
  • Computer Hardware Design (AREA)
  • General Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Business, Economics & Management (AREA)
  • General Business, Economics & Management (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)
  • Telephonic Communication Services (AREA)

Abstract

L'invention concerne un procédé de transmission de données utiles. Un premier dispositif de communication (S1) utilisé pour un codage permet d'envoyer un message d'établissement de liaison directe (DMC) et un message de codage (CRM) à destination d'un deuxième dispositif de communication (U2, C2, S2). Le message d'établissement de liaison directe (DMC) est une première adresse de liaison directe (IP_GWl) identifiant un dispositif de codage (CR, GW1) et le message de codage (CRM) se voit attribuer une deuxième adresse de liaison directe (IP_S1) identifiant le premier dispositif de communication (Sl). Si l'on constate que le deuxième dispositif de communication (U2, C2, S2) assiste le codage donné, on établit une liaison directe entre le premier et le deuxième dispositif de communication à l'aide de la deuxième adresse de liaison directe (IP_S1). En l'absence de cette constatation, on utilise la première adresse de liaison directe (IP_GW1) pour établir une liaison directe entre le deuxième dispositif de communication (U2, C2, S2) et le dispositif de codage (CR, GW1) et de là jusqu'au premier dispositif de communication (S1).
EP07704439A 2006-03-30 2007-02-07 Procédé pour la transmission sécurisée de données utiles Withdrawn EP1861984A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP07704439A EP1861984A1 (fr) 2006-03-30 2007-02-07 Procédé pour la transmission sécurisée de données utiles

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP06006790A EP1841161B1 (fr) 2006-03-30 2006-03-30 Procédé pour la transmission sécurisée de données utiles
EP07704439A EP1861984A1 (fr) 2006-03-30 2007-02-07 Procédé pour la transmission sécurisée de données utiles
PCT/EP2007/051185 WO2007113031A1 (fr) 2006-03-30 2007-02-07 Procédé de transmission sécurisée de données utiles

Publications (1)

Publication Number Publication Date
EP1861984A1 true EP1861984A1 (fr) 2007-12-05

Family

ID=36283664

Family Applications (2)

Application Number Title Priority Date Filing Date
EP06006790A Expired - Fee Related EP1841161B1 (fr) 2006-03-30 2006-03-30 Procédé pour la transmission sécurisée de données utiles
EP07704439A Withdrawn EP1861984A1 (fr) 2006-03-30 2007-02-07 Procédé pour la transmission sécurisée de données utiles

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP06006790A Expired - Fee Related EP1841161B1 (fr) 2006-03-30 2006-03-30 Procédé pour la transmission sécurisée de données utiles

Country Status (5)

Country Link
US (1) US8234716B2 (fr)
EP (2) EP1841161B1 (fr)
CN (1) CN101326793B (fr)
DE (1) DE502006000845D1 (fr)
WO (1) WO2007113031A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20100064585A (ko) * 2008-12-05 2010-06-15 삼성전자주식회사 데이터송수신장치 및 그 방법
US8892042B2 (en) 2012-06-08 2014-11-18 Apple Inc. Immediate connection following device discovery
US9204469B2 (en) * 2012-06-08 2015-12-01 Apple Inc. Duplicate connection detection for devices using random addresses
EP3713187A1 (fr) * 2019-03-19 2020-09-23 Siemens Aktiengesellschaft Procédé de transmission des paquets de données

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WO1998057599A2 (fr) 1997-06-17 1998-12-23 Sante Camilli Valvule implantable pour vaisseaux sanguins
JP3497088B2 (ja) * 1998-12-21 2004-02-16 松下電器産業株式会社 通信システム及び通信方法
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US7076653B1 (en) * 2000-06-27 2006-07-11 Intel Corporation System and method for supporting multiple encryption or authentication schemes over a connection on a network
FR2812152B1 (fr) * 2000-07-21 2003-01-31 Netcelo Communication directe entre usagers sur le reseau internet
GB0023412D0 (en) 2000-09-23 2000-11-08 Khaghani Asghar Aortic counterpulsator
US20040158704A1 (en) * 2003-02-12 2004-08-12 Avaya Technology Corp. Providing encrypted real time data transmissions on a network
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DE10354947A1 (de) 2003-11-25 2005-06-30 Siemens Ag Verfahren zur Übermittlung von Kommunikationsdaten in einem Kommunikationssystem
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Also Published As

Publication number Publication date
EP1841161B1 (fr) 2008-05-28
WO2007113031A1 (fr) 2007-10-11
CN101326793A (zh) 2008-12-17
CN101326793B (zh) 2011-11-16
US20090138705A1 (en) 2009-05-28
DE502006000845D1 (de) 2008-07-10
EP1841161A1 (fr) 2007-10-03
US8234716B2 (en) 2012-07-31

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