Nortel Networks Corporation

Cedric Aoun

Julian Mitchell

Levay Louis

Francois Audet

Patrick D Bradd

Chris Simcoe

Kevin J Baughan

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 method and system for enabling firewall traversal of media communications from a client device. The firewall infers authentication or validation of the client device based upon communications between the client device and a device controller known to the firewall. The firewall monitors packets sent from the device controller to the client device. If the device controller sends packets to the client device for a sufficiently long period of time and with sufficient frequency, or if the packets are of a certain type, then the firewall deems the client device to be validated and permits the client device to send data packets through the firewall. The device controller may include a media gateway controller, a port discovery server, or similar such device controllers. The device controller and client device communicate based upon a protocol, which need not be understood by the firewall.

Method and system for enabling firewall traversal

IP addresses are presently becoming a scarce resource, even in private IP address domains. Commonly therefore network address translators are used to map a large number of private addresses to a relatively small number of public IP address, or even map addresses between two different IP address domains. However, network address translators do not readily pass voice set-up protocols such as SIP and VoIP packets. By modifying a call server and providing an intelligent network address translator, conventional media gateways may be caused to use the intelligent address translator to route VoIP packets between IP domains having overlapping address spaces.

Methods and apparatus for setting up telephony connections between two address domains having overlapping address ranges

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.

Growing community of inventors

Boulogne, France

Cedric Aoun