Nortel Networks Corporation

Rockstar Bidco, LP

Rpx Clearinghouse LLC

Avaya Inc.

Rockstar Consortium US LP

Genband US LLC

Julian Mitchell

Mark Watson

David John Tubb

Cedric Aoun

Dany Sylvain

John Storrie

Scott Larrigan

Anthony Waters

Levay Louis

Chris Simcoe

David P Ress

Paul Kettlewell

Robert Turner

Sujata Arambepola

Neil Watts

George Bouleros

The present invention allows a network policy server or other centralized entity to provide arbitration for selecting media capabilities to use in a communication session between communication clients. In operation, the network policy server will directly or indirectly receive a first message in association with an attempt to establish a communication session from a first communication client. The first message will include the available media capabilities of the first communication client. The network policy server will apply appropriate policies for the first communication client, the network in general, or a combination thereof to select one or more of the first media capabilities to determine a second set of media capabilities, which are provided in response to the first message. This reduced set of media capabilities will ultimately be used to establish the communication session with the first communication client.

Media capability selection

An Application Server entity in an IP Multimedia Subsystem (IMS) network comprises an interface for interfacing with an application and control logic which is arranged to inspect signaling information received from the application via the interface in the form of Extensible Markup Language (XML). The received signaling information is compared with stored rule data which specifies a relationship between an element in the signaling information and an action that should be taken and output data is generated based on the comparison. The Application Server can output operational measurements and/or charging information which more accurately reflect usage made of the Application Server resources. The need for a separate OSA/Parlay-X gateway can be avoided.

Application server billing

The present invention relates to methods of, computer software for and apparatus for enabling network management in a network arrangement in which a first network is separated from a second network by a network address translator or firewall. More particularly, but not exclusively, the present invention enables, in a carrier hosted solution, a) operational information relating to a device or equipment in a customer network and for use in a network management system of a carrier network and b) control information to be provided to the device or equipment by the network management system to traverse the network address translator or firewall separating the carrier and customer networks. The traversal of the network address translator or firewall is achieved by inserting the operational or control information in keep alive signalling used maintain the NAT bind or firewall pinhole.

Network management across a NAT or firewall

In order to carry out actions such as setting up a call from an entity in the address realm of one middlebox to an entity in the address realm of another middlebox, then a middlebox control node such as a call server is used. Previously, the middlebox control node has needed to have pre-configured information about all the middleboxes and which address realms they are associated with. The present invention provides one or more middlebox-identity-providing nodes which are separate from the middlebox control node, and which are more directly connected to the end users of the service than the middlebox control node. This provides greater flexibility in network design and removes the need for middlebox information to be pre-configured at the middlebox control node. Instead, this information is sent to the middlebox control node, as part of signalling messages, from middlebox-identity-providing nodes.

Middlebox control

An Application Server entity in an IP Multimedia Subsystem (IMS) network comprises an interface for interfacing with an application and control logic which is arranged to inspect signalling information received from the application via the interface in the form of Extensible Markup Language (XML). The received signalling information is compared with stored rule data which specifies a relationship between an element in the signalling information and an action that should be taken and output data is generated based on the comparison. The Application Server can output operational measurements and/or charging information which more accurately reflect usage made of the Application Server resources. The need for a separate OSA/Parlay-X gateway can be avoided.

A VPN media proxy for communication between VPNs and external networks having different addressing schemes, has interfaces to the two or more VPNs, a configuration store, and an address translator arranged to translate the source and destination address of the information based on the configuration. Sharing of the proxy by many VPNs can keep costs down or enable more VPNs to be provided. A call server also shared by the VPNs is used to set up the session and to establish the configuration. The proxy can have an address within each VPN so that it appears to be a dedicated resource for each VPN.

Media proxy having interface to multiple virtual private networks

A media proxy receive a first message from a near end of a path of a communications session, and before receiving a corresponding message from a far end, the media proxy is arranged to detect a blocking situation where another device in the path is awaiting the first message before forwarding the corresponding message. Detecting such a blocking situation enables it to be overcome, and enables the communication session to proceed. The media proxy can send a probe message to discover if there is another media proxy along the path causing the blocking. This is useful where the only information about the far end is the media path which is in the call set up, e.g. IP address and port. Sending the probe message can be under the control of a call server.

Media proxy able to detect blocking

A VPN converter for interfacing two or more VPNs to an external network receives information relating to a communication session between an entity in any of the VPNs and the external network and converts a format such as an encoding or transmission format of the information, e.g. between VoIP packets and TDM signals for the PSTN. The converter is under the control of a call server and carries out routing and NAT functions. It determines which VPN the information relates to. By sharing the call server and converter between many VPNs, the amount of equipment can be reduced.

Convertor shared by multiple virtual private networks

In a packet based (typically IP) network, network address translation is frequently used to overcome the problem of dwindling address spaces. However, network address translation prevents the operation of many of the complex protocols used for transmission of media streams for example, data such as voice over IP or video over IP. Accordingly, media proxy devices are used to allow such data to traverse NAT boundaries. However, media proxy devices are expensive and therefore scarce and the selection of an optimum media proxy is important to obtain optimum functionality and cost effectiveness within the network. By providing a call agent in the network with a simple model of the network and providing information concerning optimum media proxies for different parts of the network, the problem of selecting an optimum media proxy during path set up is overcome.

Methods and apparatus for selecting a media proxy

A method for ascertaining the use of resources on a network having multiple paths across which data can pass. Each alternative path across the network is provided with a different address or port at a server or anchor point, such that, when a data packet is sent to a particular address it will travel across a certain path. As each path is associated with its own individual port or address a server can deduce from the port or address at which a data packet arrives which path it has traversed. The server can then use its knowledge of network topology and bandwidth availability to make policy enforcement decisions. These decisions may include whether to allow the call to proceed if the initial packet received is a call set up packet or, alternatively, a decision as to which path should be used for all transmissions from the terminal during the session.

Method for determining resource use in a network

A signaling method for use in a communication network, in particular a unified network, for supporting a communication along a communication path () via a plurality of in-path network infrastructure elements () of the network. A service element () of the network which is located off the communication path triggers an in-path network infrastructure element () and the triggered in-path network infrastructure element initiates in-path signaling along the communication path. In particular, the service element may send a message to a terminating end point of the communication, which message is intercepted by the network infrastructure element () closest to the terminating end point, which closest network infrastructure element initiates the in-path signaling.

Signaling method for communication networks

An interface for a private IP network interfaces flows of packets between gateway controllers and external media gateways. It has a network address translator and an IPsec device for maintaining secure paths to the external devices. A path identifier records which of the packet flows corresponds to which path. It is incorporated in the packet header, and means that the same interface can be used to couple many different external gateways, and interface them with many of the gateway controllers. Widespread deployment of such interfaces in anonymisers to achieve hiding of device addresses and network topology, as well as the reduction in use of expensive registered addresses is facilitated. By sending the path identifier in the packet, the IPsec device and the address translator can be loosely coupled devices, so standard readily available devices can be used.

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Maidenhead, United Kingdom

Julian Mitchell