WO2000062507A1 - Key management between a cable telephony adapter and associated signaling controller - Google Patents

Key management between a cable telephony adapter and associated signaling controller Download PDF

Info

Publication number
WO2000062507A1
WO2000062507A1 PCT/US2000/009323 US0009323W WO0062507A1 WO 2000062507 A1 WO2000062507 A1 WO 2000062507A1 US 0009323 W US0009323 W US 0009323W WO 0062507 A1 WO0062507 A1 WO 0062507A1
Authority
WO
WIPO (PCT)
Prior art keywords
key
server
endpoint
telephony
sub
Prior art date
Application number
PCT/US2000/009323
Other languages
French (fr)
Inventor
Sasha Medvinsky
Original Assignee
General Instrument Corporation
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 General Instrument Corporation filed Critical General Instrument Corporation
Priority to AT00921875T priority Critical patent/ATE313200T1/en
Priority to AU42136/00A priority patent/AU4213600A/en
Priority to EP00921875A priority patent/EP1169833B1/en
Priority to DE60024800T priority patent/DE60024800T2/en
Priority to CA2365856A priority patent/CA2365856C/en
Publication of WO2000062507A1 publication Critical patent/WO2000062507A1/en
Priority to HK02107229.6A priority patent/HK1045917B/en

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F21/60—Protecting data
    • G06F21/606—Protecting data by securing the transmission between two devices or processes
    • 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
    • H04L65/1101—Session protocols
    • 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
    • H04L63/0435—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 wherein the sending and receiving network entities apply symmetric encryption, i.e. same key used for encryption and decryption
    • 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
    • H04L63/0442—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 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption
    • 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
    • H04L63/06—Network architectures or network communication protocols for network security for supporting key management in a packet data network
    • H04L63/061—Network architectures or network communication protocols for network security for supporting key management in a packet data network for key exchange, e.g. in peer-to-peer networks
    • 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
    • H04L63/06—Network architectures or network communication protocols for network security for supporting key management in a packet data network
    • H04L63/062—Network architectures or network communication protocols for network security for supporting key management in a packet data network for key distribution, e.g. centrally by trusted party
    • 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
    • H04L63/08—Network architectures or network communication protocols for network security for authentication of entities
    • H04L63/0807—Network architectures or network communication protocols for network security for authentication of entities using tickets, e.g. Kerberos
    • 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
    • H04L63/12—Applying verification of the received information
    • 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
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
    • H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
    • H04L9/0819—Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s)
    • H04L9/083—Key transport or distribution, i.e. key establishment techniques where one party creates or otherwise obtains a secret value, and securely transfers it to the other(s) involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
    • H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
    • H04L9/0838—Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these
    • H04L9/0841—Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these involving Diffie-Hellman or related key agreement protocols
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/321—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving a third party or a trusted authority
    • H04L9/3213—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving a third party or a trusted authority using tickets or tokens, e.g. Kerberos
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/3263—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F12/00—Accessing, addressing or allocating within memory systems or architectures
    • G06F12/14—Protection against unauthorised use of memory or access to memory
    • G06F12/1408—Protection against unauthorised use of memory or access to memory by using cryptography
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2207/00—Indexing scheme relating to methods or arrangements for processing data by operating upon the order or content of the data handled
    • G06F2207/72—Indexing scheme relating to groups G06F7/72 - G06F7/729
    • G06F2207/7219—Countermeasures against side channel or fault attacks
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2211/00—Indexing scheme relating to details of data-processing equipment not covered by groups G06F3/00 - G06F13/00
    • G06F2211/007—Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress
    • G06F2211/008—Public Key, Asymmetric Key, Asymmetric Encryption
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2221/00—Indexing scheme relating to security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F2221/21—Indexing scheme relating to G06F21/00 and subgroups addressing additional information or applications relating to security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F2221/2129—Authenticate client device independently of the user

Definitions

  • This invention relates generally to key management for Client-Server systems, and more particularly, to a scalable key management system for use in IP telephony networks.
  • IP Internet Protocol
  • a network server may be responsible for setting up phone calls with up to 100,000 clients.
  • the clients may be coupled to the telephony network via cable telephony adapter (CTA) devices.
  • CTA cable telephony adapter
  • IPSec Internet Protocol Security
  • the present invention includes a highly scalable key management architecture for secure client-server systems used in IP telephony network, wherein cryptographic state needs to be saved only by the clients.
  • This architecture takes advantage of existing key management protocols, Kerberos with the PKINIT (public key) extension, to provide an IP telephony system having a high degree of scalability.
  • the architecture provides for lightweight rekeying operations that allow clients to quickly re-establish the lost association or switch to a different server.
  • a method for establishing a secure channel between an IP telephony endpoint and Server in an IP telephony network is provided.
  • the endpoint is coupled to a user and the Server is coupled to the IP telephony network.
  • the method comprises steps of transmitting from the endpoint to a key distribution center a request for a security ticket, receiving the security ticket from the key distribution center, transmitting from the endpoint to the Server a request for a sub- key, receiving the sub-key from the Server, and establishing a secure channel between the endpoint and the Server using the sub-key.
  • FIG. 1 shows a telephony network constructed in accordance with the present invention
  • FIG. 2 shows message exchange diagram for establishing a secure communication channel in accordance with the present invention
  • FIG. 3 shows a method for establishing a secure communication channel using the messages of FIG. 3.
  • Embodiments of the present invention provide for establishing a secure channel between an IP telephony endpoint and a Server in an IP telephony network.
  • a cable telephony adapter (CTA) device is representative of the IP telephony endpoint and a Signaling Controller (SC) is representative of the Server.
  • SC Signaling Controller
  • the present invention is suitable for use with other types of network endpoints and Servers not discussed herein.
  • FIG. 1 shows a portion of a telephony network 100 constructed in accordance with the present invention.
  • CTA 102 provides access to a user 104 via a Hybrid Fiber/Coax (HFC) head-end 106.
  • the HFC head-end 106 has the capacity to provide access to other users as shown at 108.
  • the HFC head-end is also coupled to a Signaling Controller (SC) 110 which is coupled to a telephony network backbone 114.
  • SC Signaling Controller
  • the Signaling Controller is used to control the CTA's access to the telephony network.
  • a key distribution center (KDC) 112 is also coupled to the telephony network backbone 114.
  • KDC key distribution center
  • the KDC 112 issues Kerberos tickets, which are in turn used to generate sub-keys for secure connection protocols, such as the IPSec encapsulating security payload (ESP) protocol, or other secure connections.
  • the network 100 also includes a customer service representative (CSR) center 116, a provisioning certification authority (C A) 118 and a billing host 120.
  • CSR customer service representative
  • C A provisioning certification authority
  • Embodiments of the present invention include the use of the Kerberos protocol with the public key PKINIT extension for key management.
  • This protocol is based on Kerberos tickets, which are cookies, encrypted with the particular server's key.
  • the Kerberos ticket is used to both authenticate a client to a server and to establish a session key, which is contained in the ticket. Accessing Kerberos services can be done using the Generic Security Service Application Program Interface (GSS-API) standard.
  • GSS-API Generic Security Service Application Program Interface
  • two-way authentication with public key certificates is used by the CTA to obtain a Signaling Controller ticket from the KDC.
  • a corresponding session key is delivered to the CTA sealed with either the CTA's public key or with a secret derived from a Diffie-Hellman exchange.
  • the Signaling Controller ticket is kept for a relatively long period of time, for example, days or weeks. The length of this period can be adjusted based on network performance requirements.
  • the Signaling Controller ticket is used to establish a symmetric session key, which is in turn used to establish a set of keys for use with the IPSec ESP mode.
  • the keys used by IPSec are not derived from the session key itself. Instead, another random key (i.e., a sub-key) is generated for each phone call and then used to derive the IPSec keys.
  • the Signaling Controller does not have to keep state. After it derives all the required keys from the sub-key and exchanges signaling messages with the CTA, the Signaling Controller can throw away the ticket along with all of the associated keys.
  • the use of the Kerberos protocol with the PKINIT extension in embodiments of the present invention provides several advantages.
  • the Signaling Controller is not required to keep state - Kerberos tickets need to be kept only by the endpoints (CTAs).
  • CTAs endpoints
  • IPSec Security Associations can be torn down when no longer needed and quickly re-established with efficient key management based on the Kerberos tickets.
  • the protocol runs over both TCP and UDP protocols, and is a widely available standard, with multiple vendors providing support for both Kerberos and PKINIT.
  • RS A is used for both key delivery and authentication.
  • a PKINIT option may be used wherein Diffie-Hellman is used for the key exchange and RS A is used for authentication.
  • embodiments of the present invention are suitable for use with any public key algorithms within PKINIT for both authentication and key exchanges.
  • FIG. 2 shows a message exchange diagram 200 illustrating how the CTA uses Kerberos to obtain the sub-key, which in turn, is used to derive IPSec ESP keys for the CTA-to-Signaling Controller signaling messages.
  • the exchange diagram 200 shows messages transmitted or received at the CTA 102 at line 220, the KDC 112 at line 222, and the Signaling Controller 110 at line 224.
  • FIG. 3 shows a flow diagram 300 illustrating how the messages of FIG. 2 are exchanged in accordance with the present invention.
  • a PKINIT Request is sent from the CTA 102 to the KDC 112 as shown by message 202.
  • This request includes the CTA signature and certificate - used by the KDC to authenticate the CTA.
  • This request also carries the current time - used by the KDC to verify that this message is not a replay or a retransmission of an old message.
  • the PKINIT Request also contains a random value (called a nonce) that will be used to bind a subsequent PKINIT Reply message to this request.
  • a nonce random value
  • the CTA will also include its Diffie-Hellman parameters and public value in the PKINIT Request.
  • the KDC 112 receives and verifies the PKINIT Request and then issues to the CTA a ticket for the Signaling Controller encrypted with the Signaling Controller's service key. Inside this encrypted ticket are a symmetric session key, its validity period and the CTA identity. Also in this step, this ticket will be sent back to the CTA 102 inside a PKINIT Reply, shown by message 204.
  • the PKINIT Reply message also contains KDC's certificate and signature for authenticating the KDC, along with the nonce from the PKINIT Request to protect against replays. If a Diffie-Hellman exchange is used, the KDC also places its Diffie-Hellman public value into this message.
  • the PKINIT Reply also contains a second copy of the session key and its validity period found in the ticket - intended to be decrypted and used by the CTA.
  • This second copy of the session key and its associated attributes are either encrypted with a Diffie-Hellman-derived secret or enveloped with the CTA's public key.
  • enveloped means that the session key along with its associated attributes are not encrypted directly with the CTA's public key.
  • the public key is used to encrypt a random symmetric key that is in turn used to encrypt another symmetric key which is then finally used to encrypt the session key and its attributes.
  • This embodiment uses the PKINIT standard as is, even though in this case, simplifications to the PKINIT Reply seem possible. If a Diffie-Hellman exchange is not used, then the Reply contains message items as shown at 226.
  • an application (AP) Request is sent from the CTA 102 to the
  • Signaling Controller 110 as shown by message 206.
  • a CTA has already obtained a Signaling Controller ticket and now initiates key management with the Signaling Controller by sending it an AP Request message.
  • the AP Request contains the Signaling Controller ticket along with the CTA name, timestamp and a message hash - all encrypted with the SC session key. The timestamp is used to check for replays of old AP Request messages.
  • the Signaling Controller 110 receives an AP Request. It first decrypts and validates the ticket with its service key. It then takes the session key out of the ticket and uses it to decrypt and validate the rest of the AP Request. Then, the Signaling Controller generates a random sub-key and encrypts it along with the current timestamp with the session key. It places this information into an AP Reply message 208 and sends it back to the CTA.
  • the CTA receives and validates the AP Reply, after which it shares the sub-key with the Signaling Controller. Both sides independently derive (with some one-way function) a set of IPSec encryption and authentication keys from this sub- key. After that, all signaling messages between the CTA and the Signaling Controller will be protected with an IPSec channel. This establishment of the IPSec channel is symbolically illustrated in FIG. 2 at 210 - even though this step does not involve an exchange of messages.
  • the PKINIT exchange is performed at long intervals in order to obtain an intermediate symmetric session key.
  • This session key is shared between the CTA and the Signaling Controller (via the Signaling Controller Ticket).
  • the PKINIT Request/Reply messages are sent over a TCP/IP connection. This is because a single PKINIT Request or Reply message, containing public key and Diffie-Hellman information may be too large to fit into a single UDP packet.
  • TCP instead of UDP may have some impact on performance, but since the PKINIT exchange occurs at infrequent intervals (days or weeks apart) and is not tied to the phone calls, the impact on performance is not significant.
  • the session key is used in the AP Request and AP Reply messages, shown at 206, 208 and are exchanged for each phone call, to establish a symmetric sub-key.
  • This sub-key is used to derive all of the IPSec ESP keys and starting sequence numbers, used for both directions.
  • the AP Request and AP Reply messages are small enough to fit into a single UDP packet, and thus will run over UDP.
  • the present invention provides a highly scalable key management architecture for secure client-server systems used in IP telephony networks. It will be apparent to those with skill in the art that modifications to the above methods and embodiments can occur without deviating from the scope of the present invention. Accordingly, the disclosures and descriptions herein are intended to be illustrative, but not limiting, of the scope of the invention which is set forth in the following claims.

Abstract

A highly scalable key management architecture for secure client-server systems used in IP telephony network, wherein cryptographic state needs to be saved only by the clients. This architecture takes advantage of existing key management protocols, Kerberos with the PKINIT (public key) extension, to provide an IP telephony system having a high degree of scalability. In the case of lost security associations, the architecture provides for lightweight rekeying operations that allow clients to quickly re-establish the lost association or switch to a different server. The key management architecture includes a method for establishing a secure channel between an IP telephony endpoint and Server in an IP telephony network. The endpoint is coupled to a user and the Server is coupled to the IP telephony network. The method comprises steps of transmitting from the endpoint to a key distribution center a request for a security ticket, receiving the security ticket from the key distribution center, transmitting from the endpoint to the Server a request for a sub-key, receiving the sub-key from the Server, and establishing a secure channel between the endpoint and the Server using the sub-key.

Description

KEY MANAGEMENT BETWEEN A CABLE TELEPHONY ADAPTER AND ASSOCIATED SIGNALING CONTROLLER
CROSS-REFERENCES TO RELATED APPLICATIONS This application claims priority from co-pending U.S. Provisional Patent Application Serial No. 60/128,772 filed April 9, 1999, the disclosure of which is incorporated herein in its entirety for all purposes.
FIELD OF THE INVENTION
This invention relates generally to key management for Client-Server systems, and more particularly, to a scalable key management system for use in IP telephony networks.
BACKGROUND OF THE INVENTION In an Internet Protocol (IP) telephony network, a network server may be responsible for setting up phone calls with up to 100,000 clients. The clients may be coupled to the telephony network via cable telephony adapter (CTA) devices. In order to secure call signaling, an Internet Protocol Security (IPSec) association is set up between each client and the server. This has to be done in a timely fashion to minimize the CPU overhead at the server and to minimize the call setup delay.
In order to handle large numbers of clients, key management needs to be as fast as possible. For example, security associations might be lost when a server goes down or become too busy to handle all of its clients. The lost security associations must then be re-establish again when needed. Manual administration of clients is unsuitable because of the high overhead costs and lack of scalability . Other techniques used in architectures unrelated to IP telephony are also not suitable, since they do not provide the desired scalability and low administration overhead. SUMMARY OF THE INVENTION The present invention includes a highly scalable key management architecture for secure client-server systems used in IP telephony network, wherein cryptographic state needs to be saved only by the clients. This architecture takes advantage of existing key management protocols, Kerberos with the PKINIT (public key) extension, to provide an IP telephony system having a high degree of scalability. In the case of lost security associations, the architecture provides for lightweight rekeying operations that allow clients to quickly re-establish the lost association or switch to a different server. In one embodiment of the present invention, a method for establishing a secure channel between an IP telephony endpoint and Server in an IP telephony network is provided. The endpoint is coupled to a user and the Server is coupled to the IP telephony network. The method comprises steps of transmitting from the endpoint to a key distribution center a request for a security ticket, receiving the security ticket from the key distribution center, transmitting from the endpoint to the Server a request for a sub- key, receiving the sub-key from the Server, and establishing a secure channel between the endpoint and the Server using the sub-key.
A further understanding of the nature and the advantages of the inventions disclosed herein may be realized by reference to the remaining portions of the specification and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a telephony network constructed in accordance with the present invention; FIG. 2 shows message exchange diagram for establishing a secure communication channel in accordance with the present invention; and
FIG. 3 shows a method for establishing a secure communication channel using the messages of FIG. 3.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
Embodiments of the present invention provide for establishing a secure channel between an IP telephony endpoint and a Server in an IP telephony network. In the embodiments discussed herein, a cable telephony adapter (CTA) device is representative of the IP telephony endpoint and a Signaling Controller (SC) is representative of the Server. However, the present invention is suitable for use with other types of network endpoints and Servers not discussed herein.
FIG. 1 shows a portion of a telephony network 100 constructed in accordance with the present invention. To access the telephony network, CTA 102 provides access to a user 104 via a Hybrid Fiber/Coax (HFC) head-end 106. The HFC head-end 106 has the capacity to provide access to other users as shown at 108. The HFC head-end is also coupled to a Signaling Controller (SC) 110 which is coupled to a telephony network backbone 114. The Signaling Controller is used to control the CTA's access to the telephony network. A key distribution center (KDC) 112, is also coupled to the telephony network backbone 114. The KDC 112 issues Kerberos tickets, which are in turn used to generate sub-keys for secure connection protocols, such as the IPSec encapsulating security payload (ESP) protocol, or other secure connections. The network 100 also includes a customer service representative (CSR) center 116, a provisioning certification authority (C A) 118 and a billing host 120. Thus, in the network 100 it is possible for the user 104 to access the telephony backbone 114 via the CTA 102 using a secure protocol.
Embodiments of the present invention include the use of the Kerberos protocol with the public key PKINIT extension for key management. This protocol is based on Kerberos tickets, which are cookies, encrypted with the particular server's key. The Kerberos ticket is used to both authenticate a client to a server and to establish a session key, which is contained in the ticket. Accessing Kerberos services can be done using the Generic Security Service Application Program Interface (GSS-API) standard. In one embodiment of the present invention, two-way authentication with public key certificates is used by the CTA to obtain a Signaling Controller ticket from the KDC. A corresponding session key is delivered to the CTA sealed with either the CTA's public key or with a secret derived from a Diffie-Hellman exchange. The Signaling Controller ticket is kept for a relatively long period of time, for example, days or weeks. The length of this period can be adjusted based on network performance requirements. In addition, the Signaling Controller ticket is used to establish a symmetric session key, which is in turn used to establish a set of keys for use with the IPSec ESP mode. The keys used by IPSec are not derived from the session key itself. Instead, another random key (i.e., a sub-key) is generated for each phone call and then used to derive the IPSec keys. Thus, the Signaling Controller does not have to keep state. After it derives all the required keys from the sub-key and exchanges signaling messages with the CTA, the Signaling Controller can throw away the ticket along with all of the associated keys.
The use of the Kerberos protocol with the PKINIT extension in embodiments of the present invention provides several advantages. For example, the Signaling Controller is not required to keep state - Kerberos tickets need to be kept only by the endpoints (CTAs). Also, IPSec Security Associations can be torn down when no longer needed and quickly re-established with efficient key management based on the Kerberos tickets. The protocol runs over both TCP and UDP protocols, and is a widely available standard, with multiple vendors providing support for both Kerberos and PKINIT.
In one embodiment, within the PKINIT protocol, RS A is used for both key delivery and authentication. In another embodiment, a PKINIT option may be used wherein Diffie-Hellman is used for the key exchange and RS A is used for authentication. In general, embodiments of the present invention are suitable for use with any public key algorithms within PKINIT for both authentication and key exchanges.
FIG. 2 shows a message exchange diagram 200 illustrating how the CTA uses Kerberos to obtain the sub-key, which in turn, is used to derive IPSec ESP keys for the CTA-to-Signaling Controller signaling messages. In the exchange diagram 200, only some of the information carried in the messages is provided in order to present a clear description of the protocol. The exchange diagram 200 shows messages transmitted or received at the CTA 102 at line 220, the KDC 112 at line 222, and the Signaling Controller 110 at line 224.
FIG. 3 shows a flow diagram 300 illustrating how the messages of FIG. 2 are exchanged in accordance with the present invention.
At block 302, a PKINIT Request is sent from the CTA 102 to the KDC 112 as shown by message 202. This request includes the CTA signature and certificate - used by the KDC to authenticate the CTA. This request also carries the current time - used by the KDC to verify that this message is not a replay or a retransmission of an old message. The PKINIT Request also contains a random value (called a nonce) that will be used to bind a subsequent PKINIT Reply message to this request. In the case that a Diffie-Hellman exchange is used, the CTA will also include its Diffie-Hellman parameters and public value in the PKINIT Request. At block 304, the KDC 112 receives and verifies the PKINIT Request and then issues to the CTA a ticket for the Signaling Controller encrypted with the Signaling Controller's service key. Inside this encrypted ticket are a symmetric session key, its validity period and the CTA identity. Also in this step, this ticket will be sent back to the CTA 102 inside a PKINIT Reply, shown by message 204. The PKINIT Reply message also contains KDC's certificate and signature for authenticating the KDC, along with the nonce from the PKINIT Request to protect against replays. If a Diffie-Hellman exchange is used, the KDC also places its Diffie-Hellman public value into this message.
The PKINIT Reply also contains a second copy of the session key and its validity period found in the ticket - intended to be decrypted and used by the CTA. This second copy of the session key and its associated attributes are either encrypted with a Diffie-Hellman-derived secret or enveloped with the CTA's public key. Here, enveloped means that the session key along with its associated attributes are not encrypted directly with the CTA's public key. Within the PKINIT Reply the public key is used to encrypt a random symmetric key that is in turn used to encrypt another symmetric key which is then finally used to encrypt the session key and its attributes. This embodiment uses the PKINIT standard as is, even though in this case, simplifications to the PKINIT Reply seem possible. If a Diffie-Hellman exchange is not used, then the Reply contains message items as shown at 226. At block 306, an application (AP) Request is sent from the CTA 102 to the
Signaling Controller 110 as shown by message 206. Here, a CTA has already obtained a Signaling Controller ticket and now initiates key management with the Signaling Controller by sending it an AP Request message. The AP Request contains the Signaling Controller ticket along with the CTA name, timestamp and a message hash - all encrypted with the SC session key. The timestamp is used to check for replays of old AP Request messages.
At block 308, the Signaling Controller 110 receives an AP Request. It first decrypts and validates the ticket with its service key. It then takes the session key out of the ticket and uses it to decrypt and validate the rest of the AP Request. Then, the Signaling Controller generates a random sub-key and encrypts it along with the current timestamp with the session key. It places this information into an AP Reply message 208 and sends it back to the CTA. At block 310, the CTA receives and validates the AP Reply, after which it shares the sub-key with the Signaling Controller. Both sides independently derive (with some one-way function) a set of IPSec encryption and authentication keys from this sub- key. After that, all signaling messages between the CTA and the Signaling Controller will be protected with an IPSec channel. This establishment of the IPSec channel is symbolically illustrated in FIG. 2 at 210 - even though this step does not involve an exchange of messages.
In the embodiment of the invention depicted in FIGS. 2 and 3, the PKINIT exchange is performed at long intervals in order to obtain an intermediate symmetric session key. This session key is shared between the CTA and the Signaling Controller (via the Signaling Controller Ticket).
In this embodiment, the PKINIT Request/Reply messages, shown at 202 and 204, are sent over a TCP/IP connection. This is because a single PKINIT Request or Reply message, containing public key and Diffie-Hellman information may be too large to fit into a single UDP packet. The use of TCP instead of UDP may have some impact on performance, but since the PKINIT exchange occurs at infrequent intervals (days or weeks apart) and is not tied to the phone calls, the impact on performance is not significant.
The session key is used in the AP Request and AP Reply messages, shown at 206, 208 and are exchanged for each phone call, to establish a symmetric sub-key. This sub-key is used to derive all of the IPSec ESP keys and starting sequence numbers, used for both directions. The AP Request and AP Reply messages are small enough to fit into a single UDP packet, and thus will run over UDP.
The present invention provides a highly scalable key management architecture for secure client-server systems used in IP telephony networks. It will be apparent to those with skill in the art that modifications to the above methods and embodiments can occur without deviating from the scope of the present invention. Accordingly, the disclosures and descriptions herein are intended to be illustrative, but not limiting, of the scope of the invention which is set forth in the following claims.

Claims

WHAT IS CLAIMED IS:
L A method for establishing a secure channel between an IP telephony endpoint and Server in an IP telephony network, wherein the endpoint is coupled to a user and the Server is coupled to the IP telephony network, the method comprising steps of: transmitting from the endpoint to a key distribution center a request for a security ticket; receiving the security ticket from the key distribution center; transmitting from the endpoint to the Server a request for a sub-key; receiving the sub-key from the Server; and establishing a secure channel between the endpoint and the Server using the sub-key.
2. The method of claim 1 , wherein the endpoint is a cable telephony adapter.
3. The method of claim 1 , wherein the server is a Signaling Controller.
4. The method of claim 1 , wherein the secure channel is an IPSec channel.
PCT/US2000/009323 1999-04-09 2000-04-07 Key management between a cable telephony adapter and associated signaling controller WO2000062507A1 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
AT00921875T ATE313200T1 (en) 1999-04-09 2000-04-07 KEY MANAGEMENT BETWEEN CABLE TELEPHONE SYSTEM ADAPTER AND SIGNAL DEVICE CONTROL
AU42136/00A AU4213600A (en) 1999-04-09 2000-04-07 Key management between a cable telephony adapter and associated signaling controller
EP00921875A EP1169833B1 (en) 1999-04-09 2000-04-07 Key management between a cable telephony adapter and associated signaling controller
DE60024800T DE60024800T2 (en) 1999-04-09 2000-04-07 KEY MANAGEMENT BETWEEN CABLE TELEPHONE SYSTEM ADAPTER AND SIGNAL EQUIPMENT CONTROL
CA2365856A CA2365856C (en) 1999-04-09 2000-04-07 Key management between a cable telephony adapter and associated signaling controller
HK02107229.6A HK1045917B (en) 1999-04-09 2002-10-02 Key management between a cable telephony adapter and associated signaling controller

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US12877299P 1999-04-09 1999-04-09
US60/128,772 1999-04-09

Publications (1)

Publication Number Publication Date
WO2000062507A1 true WO2000062507A1 (en) 2000-10-19

Family

ID=22436900

Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/US2000/009318 WO2000062519A2 (en) 1999-04-09 2000-04-07 Built-in manufacturer's certificates for a cable telephony adapter to provide device and service certification
PCT/US2000/009323 WO2000062507A1 (en) 1999-04-09 2000-04-07 Key management between a cable telephony adapter and associated signaling controller

Family Applications Before (1)

Application Number Title Priority Date Filing Date
PCT/US2000/009318 WO2000062519A2 (en) 1999-04-09 2000-04-07 Built-in manufacturer's certificates for a cable telephony adapter to provide device and service certification

Country Status (9)

Country Link
US (2) US7568223B2 (en)
EP (2) EP1171989A2 (en)
CN (1) CN1127835C (en)
AT (1) ATE313200T1 (en)
AU (2) AU4079200A (en)
CA (2) CA2370471A1 (en)
DE (1) DE60024800T2 (en)
HK (1) HK1045917B (en)
WO (2) WO2000062519A2 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2845226A1 (en) * 2002-10-01 2004-04-02 France Telecom METHOD AND INSTALLATION FOR CONTROLLING THE IDENTITY OF THE TRANSMITTER OF A TELEPHONE CALL ON AN INTERNET NETWORK AND TELEPHONY TERMINAL FOR SUCH AN INSTALLATION
EP1510030A1 (en) * 2002-05-15 2005-03-02 Eruces, Inc. Hidden link dynamic key manager for use in computer systems
US6966003B1 (en) * 2001-01-12 2005-11-15 3Com Corporation System and method for switching security associations
WO2006038986A1 (en) * 2004-09-30 2006-04-13 Citrix Systems, Inc. Method and apparatus for associating and renewing session tickets in a ticket hierarchy
WO2007062672A1 (en) * 2005-11-30 2007-06-07 Telecom Italia S.P.A. Method and system for automated and secure provisioning of service access credentials for on-line services to users of mobile communication terminals
US7568223B2 (en) * 1999-04-09 2009-07-28 General Instrumental Corporation Internet protocol telephony security architecture
US9009721B2 (en) 2007-10-20 2015-04-14 Citrix Systems, Inc. Method and system for communicating between isolation environments
FR3018371A1 (en) * 2014-03-10 2015-09-11 Commissariat Energie Atomique REMOTE KEY DATA ENCRYPTION / ENCRYPTION METHOD AND SYSTEM AND PRIOR CHECK CHECK
US9311502B2 (en) 2004-09-30 2016-04-12 Citrix Systems, Inc. Method and system for assigning access control levels in providing access to networked content files
US9401931B2 (en) 2006-11-08 2016-07-26 Citrix Systems, Inc. Method and system for dynamically associating access rights with a resource
US9401906B2 (en) 2004-09-30 2016-07-26 Citrix Systems, Inc. Method and apparatus for providing authorized remote access to application sessions

Families Citing this family (48)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8156223B2 (en) * 2001-03-20 2012-04-10 Microsoft Corporation Distribution of binary executables and content from peer locations/machines
US8555062B1 (en) * 2001-03-26 2013-10-08 Access Co., Ltd. Protocol to prevent replay attacks on secured wireless transactions
US7181620B1 (en) * 2001-11-09 2007-02-20 Cisco Technology, Inc. Method and apparatus providing secure initialization of network devices using a cryptographic key distribution approach
KR100415117B1 (en) * 2002-03-04 2004-01-13 삼성전자주식회사 Apparatus and method for called compulsive on multi call into internet protocol phone in an internet protocol telephony system
US7565537B2 (en) * 2002-06-10 2009-07-21 Microsoft Corporation Secure key exchange with mutual authentication
JP4397675B2 (en) * 2003-11-12 2010-01-13 株式会社日立製作所 Computer system
JP4559794B2 (en) * 2004-06-24 2010-10-13 株式会社東芝 Microprocessor
US7464267B2 (en) * 2004-11-01 2008-12-09 Innomedia Pte Ltd. System and method for secure transmission of RTP packets
WO2006077822A1 (en) * 2005-01-24 2006-07-27 Matsushita Electric Industrial Co., Ltd. Signature generation device and signature verification device
US7890634B2 (en) 2005-03-18 2011-02-15 Microsoft Corporation Scalable session management
US7650505B1 (en) * 2005-06-17 2010-01-19 Sun Microsystems, Inc. Methods and apparatus for persistence of authentication and authorization for a multi-tenant internet hosted site using cookies
US7545810B2 (en) * 2005-07-01 2009-06-09 Cisco Technology, Inc. Approaches for switching transport protocol connection keys
WO2007062392A2 (en) * 2005-11-23 2007-05-31 Riverain Medical Group, Llc Computer-aided diagnosis using dual-energy subtraction images
KR100652017B1 (en) * 2005-12-08 2006-12-01 한국전자통신연구원 Method for security of docsis cable modem against physical security attacks
US7706381B2 (en) * 2006-01-10 2010-04-27 Cisco Technology, Inc. Approaches for switching transport protocol connection keys
US8140851B1 (en) * 2006-02-24 2012-03-20 Cisco Technology, Inc. Approaches for automatically switching message authentication keys
US8732279B2 (en) * 2006-08-18 2014-05-20 Cisco Technology, Inc. Secure network deployment
CA2571891C (en) * 2006-12-21 2015-11-24 Bce Inc. Device authentication and secure channel management for peer-to-peer initiated communications
BRPI0721542A2 (en) * 2007-04-30 2013-01-22 Hewlett Packard Development Co system for distributing node configuration information to a plurality of nodes in an event, method for distributing node configuration information for a plurality of nodes in an event and machine readable medium
CN101803271B (en) 2007-09-17 2012-12-12 爱立信电话股份有限公司 Method and arrangement in a telecommunication system
CN101286840B (en) * 2008-05-29 2014-07-30 西安西电捷通无线网络通信股份有限公司 Key distributing method and system using public key cryptographic technique
US7877503B2 (en) * 2008-07-02 2011-01-25 Verizon Patent And Licensing Inc. Method and system for an intercept chain of custody protocol
US8776238B2 (en) * 2008-07-16 2014-07-08 International Business Machines Corporation Verifying certificate use
KR101255987B1 (en) * 2008-12-22 2013-04-17 한국전자통신연구원 Paring method between SM and TP in downloadable conditional access system, Setopbox and Authentication device using this
US20110013762A1 (en) * 2009-07-18 2011-01-20 Gregg Bieser Notification apparatus & method
EP2484084B1 (en) * 2009-09-30 2019-03-27 Orange Method and devices allowing communication secure against denial of services (dos) and against flooding attacks in a telecommunications network
US20110302416A1 (en) * 2010-03-15 2011-12-08 Bigband Networks Inc. Method and system for secured communication in a non-ctms environment
US8347080B2 (en) 2010-05-10 2013-01-01 Research In Motion Limited System and method for multi-certificate and certificate authority strategy
EP2387262B1 (en) * 2010-05-10 2015-04-29 BlackBerry Limited System and method for multi-certificate and certificate authority strategy
US8566596B2 (en) * 2010-08-24 2013-10-22 Cisco Technology, Inc. Pre-association mechanism to provide detailed description of wireless services
US8938619B2 (en) * 2010-12-29 2015-01-20 Adobe Systems Incorporated System and method for decrypting content samples including distinct encryption chains
US8843737B2 (en) * 2011-07-24 2014-09-23 Telefonaktiebolaget L M Ericsson (Publ) Enhanced approach for transmission control protocol authentication option (TCP-AO) with key management protocols (KMPS)
EP3211933A1 (en) 2011-10-28 2017-08-30 NEC Corporation Secure method for mtc device triggering
US9026784B2 (en) * 2012-01-26 2015-05-05 Mcafee, Inc. System and method for innovative management of transport layer security session tickets in a network environment
CN104704789B (en) * 2012-10-15 2018-06-22 诺基亚通信公司 Network authentication
US9515996B1 (en) * 2013-06-28 2016-12-06 EMC IP Holding Company LLC Distributed password-based authentication in a public key cryptography authentication system
US9553982B2 (en) * 2013-07-06 2017-01-24 Newvoicemedia, Ltd. System and methods for tamper proof interaction recording and timestamping
JP6278651B2 (en) * 2013-09-27 2018-02-14 キヤノン株式会社 Network system, management server system, control method and program
US20170163607A1 (en) * 2015-12-03 2017-06-08 Microsoft Technology Licensing, Llc Establishing a Communication Event Using Secure Signalling
US10263788B2 (en) * 2016-01-08 2019-04-16 Dell Products, Lp Systems and methods for providing a man-in-the-middle proxy
US10009380B2 (en) 2016-01-08 2018-06-26 Secureworks Corp. Systems and methods for security configuration
US20180123782A1 (en) * 2016-10-27 2018-05-03 Motorola Solutions, Inc. Method for secret origination service to distribute a shared secret
EP3501654B1 (en) 2017-12-22 2021-08-25 Tecan Trading Ag Pipetting apparatus with a pipette tube and method for detecting a liquid within an intermediate section of pipette tube
US10771269B2 (en) * 2018-03-09 2020-09-08 Cisco Technology, Inc. Automated intelligent node for hybrid fiber-coaxial (HFC) networks
US10630467B1 (en) 2019-01-04 2020-04-21 Blue Ridge Networks, Inc. Methods and apparatus for quantum-resistant network communication
US11063753B2 (en) 2019-03-20 2021-07-13 Arris Enterprises Llc Secure distribution of device key sets over a network
US11743242B2 (en) * 2020-07-27 2023-08-29 Charter Communications Operating, Llc Establishing an encrypted communications channel without prior knowledge of the encryption key
CN112492004B (en) * 2020-11-17 2023-02-17 深圳市晨北科技有限公司 Method, device, system and storage medium for establishing local communication link

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5602918A (en) * 1995-12-22 1997-02-11 Virtual Open Network Environment Corp. Application level security system and method
WO1997047118A1 (en) * 1996-06-04 1997-12-11 Telefonaktiebolaget Lm Ericsson (Publ) A telephone doubler arrangement
WO1998036522A1 (en) * 1997-02-12 1998-08-20 Gte Laboratories Incorporated Method for providing secure remote command execution
US5867495A (en) * 1996-11-18 1999-02-02 Mci Communications Corporations System, method and article of manufacture for communications utilizing calling, plans in a hybrid network

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5235642A (en) 1992-07-21 1993-08-10 Digital Equipment Corporation Access control subsystem and method for distributed computer system using locally cached authentication credentials
DE69312328T2 (en) * 1993-09-20 1998-01-08 Ibm SYSTEM AND METHOD FOR CHANGING THE KEY OR PASSWORD IN A COMMUNICATION NETWORK WITH KEY DISTRIBUTION
US5544322A (en) * 1994-05-09 1996-08-06 International Business Machines Corporation System and method for policy-based inter-realm authentication within a distributed processing system
IL113259A (en) * 1995-04-05 2001-03-19 Diversinet Corp Apparatus and method for safe communication handshake and data transfer
US5796830A (en) * 1996-07-29 1998-08-18 International Business Machines Corporation Interoperable cryptographic key recovery system
US5864665A (en) * 1996-08-20 1999-01-26 International Business Machines Corporation Auditing login activity in a distributed computing environment
US5917817A (en) * 1996-12-06 1999-06-29 International Business Machines Corporation User invocation of services in public switched telephone network via parallel data networks
KR20010006455A (en) 1997-04-15 2001-01-26 엠씨아이 월드콤 인코포레이티드 A system, method and article of manufacture for switched telephony communication
US5999612A (en) * 1997-05-27 1999-12-07 International Business Machines Corporation Integrated telephony and data services over cable networks
AU4079200A (en) * 1999-04-09 2000-11-14 General Instrument Corporation Built-in manufacturer's certificates for a cable telephony adapter to provide device and service certification
WO2002025899A1 (en) * 2000-09-22 2002-03-28 General Instrument Corporation Internet protocol telephony security architecture
US20030163693A1 (en) * 2002-02-28 2003-08-28 General Instrument Corporation Detection of duplicate client identities in a communication system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5602918A (en) * 1995-12-22 1997-02-11 Virtual Open Network Environment Corp. Application level security system and method
WO1997047118A1 (en) * 1996-06-04 1997-12-11 Telefonaktiebolaget Lm Ericsson (Publ) A telephone doubler arrangement
US5867495A (en) * 1996-11-18 1999-02-02 Mci Communications Corporations System, method and article of manufacture for communications utilizing calling, plans in a hybrid network
WO1998036522A1 (en) * 1997-02-12 1998-08-20 Gte Laboratories Incorporated Method for providing secure remote command execution

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7568223B2 (en) * 1999-04-09 2009-07-28 General Instrumental Corporation Internet protocol telephony security architecture
US6966003B1 (en) * 2001-01-12 2005-11-15 3Com Corporation System and method for switching security associations
EP1510030A4 (en) * 2002-05-15 2011-08-24 Eruces Inc Hidden link dynamic key manager for use in computer systems
EP1510030A1 (en) * 2002-05-15 2005-03-02 Eruces, Inc. Hidden link dynamic key manager for use in computer systems
WO2004032430A2 (en) * 2002-10-01 2004-04-15 France Telecom Method and installation for controlling a telephone call transmitter on an internet network and telephone terminal therefor
WO2004032430A3 (en) * 2002-10-01 2004-09-23 France Telecom Method and installation for controlling a telephone call transmitter on an internet network and telephone terminal therefor
FR2845226A1 (en) * 2002-10-01 2004-04-02 France Telecom METHOD AND INSTALLATION FOR CONTROLLING THE IDENTITY OF THE TRANSMITTER OF A TELEPHONE CALL ON AN INTERNET NETWORK AND TELEPHONY TERMINAL FOR SUCH AN INSTALLATION
US9311502B2 (en) 2004-09-30 2016-04-12 Citrix Systems, Inc. Method and system for assigning access control levels in providing access to networked content files
WO2006038986A1 (en) * 2004-09-30 2006-04-13 Citrix Systems, Inc. Method and apparatus for associating and renewing session tickets in a ticket hierarchy
US9401906B2 (en) 2004-09-30 2016-07-26 Citrix Systems, Inc. Method and apparatus for providing authorized remote access to application sessions
WO2007062672A1 (en) * 2005-11-30 2007-06-07 Telecom Italia S.P.A. Method and system for automated and secure provisioning of service access credentials for on-line services to users of mobile communication terminals
US9015473B2 (en) 2005-11-30 2015-04-21 Telecom Italia S.P.A. Method and system for automated and secure provisioning of service access credentials for on-line services to users of mobile communication terminals
US9401931B2 (en) 2006-11-08 2016-07-26 Citrix Systems, Inc. Method and system for dynamically associating access rights with a resource
US9009721B2 (en) 2007-10-20 2015-04-14 Citrix Systems, Inc. Method and system for communicating between isolation environments
US9009720B2 (en) 2007-10-20 2015-04-14 Citrix Systems, Inc. Method and system for communicating between isolation environments
US9021494B2 (en) 2007-10-20 2015-04-28 Citrix Systems, Inc. Method and system for communicating between isolation environments
FR3018371A1 (en) * 2014-03-10 2015-09-11 Commissariat Energie Atomique REMOTE KEY DATA ENCRYPTION / ENCRYPTION METHOD AND SYSTEM AND PRIOR CHECK CHECK
EP2919412A1 (en) * 2014-03-10 2015-09-16 Commissariat à l'Énergie Atomique et aux Énergies Alternatives Method and system for encrypting/decrypting data with a remote key and prior token verification
US10057054B2 (en) 2014-03-10 2018-08-21 Commissariat à l'énergie atomique et aux énergies alternatives Method and system for remotely keyed encrypting/decrypting data with prior checking a token

Also Published As

Publication number Publication date
DE60024800D1 (en) 2006-01-19
CN1127835C (en) 2003-11-12
CA2370471A1 (en) 2000-10-19
EP1171989A2 (en) 2002-01-16
DE60024800T2 (en) 2006-07-06
CA2365856C (en) 2011-11-01
EP1169833A1 (en) 2002-01-09
WO2000062519A3 (en) 2001-02-08
US20090323954A1 (en) 2009-12-31
WO2000062519A2 (en) 2000-10-19
US8544077B2 (en) 2013-09-24
EP1169833B1 (en) 2005-12-14
HK1045917B (en) 2004-09-10
HK1045917A1 (en) 2002-12-13
WO2000062519A9 (en) 2002-02-21
US20050027985A1 (en) 2005-02-03
CN1346563A (en) 2002-04-24
CA2365856A1 (en) 2000-10-19
AU4079200A (en) 2000-11-14
US7568223B2 (en) 2009-07-28
ATE313200T1 (en) 2005-12-15
AU4213600A (en) 2000-11-14

Similar Documents

Publication Publication Date Title
CA2365856C (en) Key management between a cable telephony adapter and associated signaling controller
US11477037B2 (en) Providing forward secrecy in a terminating SSL/TLS connection proxy using ephemeral Diffie-Hellman key exchange
KR101013427B1 (en) End-to-end protection of media stream encryption keys for voice-over-IP systems
EP2561663B1 (en) Server and method for providing secured access to services
US8559640B2 (en) Method of integrating quantum key distribution with internet key exchange protocol
CA2703719C (en) Method and system for secure session establishment using identity-based encryption (vdtls)
US6091820A (en) Method and apparatus for achieving perfect forward secrecy in closed user groups
US7222234B2 (en) Method for key agreement for a cryptographic secure point—to—multipoint connection
JP2004254027A (en) Server device, key managing device, and encryption communication method and program
CA2546553A1 (en) System and method for provisioning and authenticating via a network
WO2009143766A1 (en) Method, system for distributing key and method, system for online updating public key
WO2009082950A1 (en) Key distribution method, device and system
EP2244420B1 (en) Method and apparatus for recovering the connection
EP3216163B1 (en) Providing forward secrecy in a terminating ssl/tls connection proxy using ephemeral diffie-hellman key exchange
KR20070006913A (en) Fast and secure connectivity for a mobile node
JP2017135527A (en) Communication device
Mihai Packet Cable Security Architecture
Schwiderski-Grosche et al. Public key based network access
Backbone 4 Conventions
Annex IPCablecom Admin guidelines & best practices

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 00806089.4

Country of ref document: CN

AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP LR LS LT LU LV MA MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
ENP Entry into the national phase

Ref document number: 2365856

Country of ref document: CA

Ref document number: 2365856

Country of ref document: CA

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 2000921875

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 2000921875

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: JP

WWG Wipo information: grant in national office

Ref document number: 2000921875

Country of ref document: EP