Alcatel Lucent

Alcatel-lucent USA Inc.

Thierry C Bessis

Jairo Orlando Esteban

Mauricio Cortes

Marianne Picha

Ashwin Vishanji Rana

Xin Tao

A SIP firewall defends an IMS network against SIP registration-based DoS/DDoS attacks by issuing fake authentication challenges when suspiciously high registration traffic is present. The fake authentication challenges include a predictive nonce that is to be used in the challenge response, thus forcing users to be state-aware and to issue the SIP registration requests from valid IP address in order to successfully respond to the fake authentication challenges. Upon confirming an association between the challenge response and the fake authentication challenges, the firewall opens a registration window to a protected node of the core network. In such manner, the firewall opens a registration window to (unauthenticated) legitimate users while stopping DDoS mode of registrations (or at least making them extremely difficult and costly) without impacting or involving the protected node.

Session initiation protocol (SIP) firewall for IP multimedia subsystem (IMS) core

Systems and methods are disclosed for system for processing calls to a SIP or VoIP device using the called party's Email address in which a call redirect server component is provisioned with the called party's Email address and VoIP or SIP device address, and a DNS system is updated with the called party's Email address and an address of the call redirect server. VoIP calls or other SIP sessions directed to the called party's Email address are resolved by the DNS system to the address of the redirect server, which in turn redirects the calls to the called party's VoIP or SIP device. The subscriber called party may provision the call redirect server with updated Email address or VoIP or SIP device address information to allow the subscribed to change VoIP phone service providers while callers only need to remember the subscriber's Email address.

System and method for processing calls to VoIP devices using the called party's email address

A method and apparatus for encoding a SIP message into an internal binary format so that it can be treated much more efficiently by both the SIP stack layers and the application. Only one memory buffer is used to handle any sort of SIP message. For this reason, this new SIP message may be called a 'mono-block' structure. It allows each SIP header's raw text from the original SIP message to be directly referred within the SIP mono-block with no additional copy. Only SIP headers that are 'used' by the application, or by some SIP stack layer are parsed to form a &#x201c;decoded&#x201d; header object. The header parsing is made &#x201c;on demand&#x201d; at the moment header is accessed. Headers not used are not decoded and are left in text format with no additional processing needed.

Method and apparatus for SIP messaging

A method and apparatus for load balancing and overload control of packet media gateways under control of a single media gateway controller is provided. More particularly, the invention is directed to a technique for load balancing and overload control by defining an interface between the media gateway (MG) and the media gateway controller (MGC) to handle both load balancing as well as general congestion and resource congestion. In addition, a new event strategy is defined that reports resource utilization so that the media gateway controller (MGC) can take appropriate action to maximize call completion. Such action may include evenly distributing traffic among available media gateways, smart routing around a congested media gateway or intelligent throttling of traffic based on knowledge of specific resources that are congested.

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Naperville, IL, United States of America

Thierry C Bessis