Nortel Networks Corporation

Rockstar Consortium US LP

Rockstar Bidco, LP

Rpx Clearinghouse LLC

Lakshminath Dondeti

Donald Fedyk

Haixiang He

Michael C Lee

Frank Horsfall

Thomas P Hardjono

Hong Zhang

Ravi Ravindran

A device for use in a system with multiple receiving units, and multiple intermediate units each configured to communicate with the device and at least some of the multiple receiving units, includes a communication module configured to send information toward and receive information from the receiving units and the intermediate units, a memory, and a processor coupled to the memory and the communication module. The processor is configured to: cause the communication module to send information toward each of the receiving units sufficient for the receiving units to obtain a key chain corresponding to that receiving unit, each key chain containing a plurality of keys, each key in each key chain being related to other keys in the respective key chains by at least one inverse of a one-way function; select a key from a key chain associated with a particular receiving unit and stored in the memory; and cause the communication module to send the selected key, and an indication of which receiving unit the selected key is associated with, toward the intermediate unit associated with the particular receiving unit.

Secure group communications

A method and apparatus is disclosed which enables detection of undesired packets received at a device in a network, where the device is a member of a group of devices in the network. A registration table stores transform identifiers for each member of a group and controls the forwarding of the transform identifiers to the members of the group as members are added and deleted. A transform identifier indicates a format or transformation of a packet transmitted by an associated member. The transform identifier can therefore be used at a receiving device to distinguish between transmissions by different members of the group, thereby enabling the receiving device to extract sequence information associated with the member from the packet. The sequence information can be compared against an expected sequence number for the member to determine whether the packet is an undesirable or rogue packet.

Method and apparatus for providing replay protection in systems using group security associations

Entropy obtained from a series of key generation exchanges may be combined with entropy from a strong entropy source to allow the strong entropy to be stretched to generate a larger number of keys for use on a communication network, without requiring additional information from the group members and without requiring the entropy source to be increased in size or in number. In one embodiment, nonces exchanged during an initial key exchange are used to generate additional key material that is then fed, together with a fresh random secret, to another pseudo-random function to generate an additional key stream. The fresh ransom secret may be generated at the GCKS from a physical entropy source or other entropy source, and may be changed at will by the GCKS to further increase the strength of the keys. The methods are particularly useful for group key management where a large number of keys are required to be generated in a short time frame.

Method and apparatus for generating large numbers of encryption keys

Routing information may be provided to VPN sites on demand to allow smaller VPN sites with smaller routing tables to communicate directly with other VPN sites. This allows the meshed VPN architecture to scale to a size larger than where each VPN site is required to store routing information for all other VPN sites. A route server is instantiated on the network, optionally in connection with a Group Controller Key Server, to manage distribution of routes on the network and to provide routes to VPN sites on demand. As routes are learned by the VPN sites they are advertised to the route server, which selectively advertises the routes to other VPN sites depending on the per-site preferences. When a VPN site needs routing information to communicate with another VPN site, the network element will check its routing table for the route, and if the route is not available, will obtain the route on-demand from the route server.

Method and apparatus for obtaining routing information on demand in a virtual private network

Method and apparatus that enable secure transmission of data in a scalable private network are described. Each station that is to be part of a private network registers with a key table. A group security association associated with the private network is forwarded to each trusted ingress and egress point that communicates with each member of the private network. When a member of the private network seeks to communicate with another member, it simply forwards the communication to the trusted ingress point. The trusted ingress point uses the security association associated with the private network to transform the communication and forwards the transformed communication through other intermediate stations in the network until it reaches a trusted egress point. The trusted egress point uses the stored security association to decode the transformed communication and forwards the communication to the appropriate destination. The ingress and egress points may be any points in the network, including customer edge devices, provider edge devices, or some combination thereof.

Method an apparatus for providing a scalable and secure network without point to point associations

Each member of a group registers with the Security/Routing (S/R) deviceand receives a Group Security Association (GSA) associated with the group. The member may register as part of a group by identifying the group and the other members. Alternatively, Routing Functionality auto-discovers the other members of the group. AS members are identified, Routing functionality reflects the routes of all members in the group to all other members of the group. The forwarding of the routes to the respective group members may be secured via the GSA associated with the group. Each member can forward communication directly to the group members, securing the communication using the group SA and standard tunneling techniques (such as IPsec, GRE, MPLS, etc.). Thus the S/R provides a mechanism for private networks to be built on top of an existing network without modification of any existing network components and much more scalable in operation and configuration than individual IP sec tunnels.

Self-configuring method and apparatus for providing secure communication between members of a group

A method for managing encryption keys in a communication system having a plurality of communication devices includes establishing a set of cryptographic keys for secure communication. Each of the cryptographic keys is associated with a geographic region. A geographic region is determined for a communication device and at least one cryptographic key is distributed to the communication device based on the geographic region of the communication device. At least one cryptographic key may be used to derive further cryptographic keys associated with a set of sub-regions of the geographic region associated with the communication device.

System and method for key management across geographic domains

Scalable, distributed method and apparatus for transforming packets to enable secure communication between two stations

Scalable method and apparatus for transforming packets to enable secure communication between two stations

A method for preserving security associations between at least two entities includes the steps of maintaining a security association relating to communication between the at least two entities in a table, and periodically storing the security association in non-volatile storage. With such an arrangement, in the event that data within the table become corrupted, it can be retrieved from storage. Because the key data is stored, performance losses due to re-establishing the secure group are minimized. In one embodiment, the security association is advantageously encrypted prior to storage to further secure the security associations for each member.

Security association storage and recovery in group key management

A method and apparatus has been described that permits fast re-establishment of secure communications between endpoints in a network through intelligent re-use of existing security associations.

Growing community of inventors

Chelmsford, MA, United States of America

Lakshminath Dondeti