Abstract: A method is disclosed that enables the screening of unwanted telephone calls, such as voice or video calls, for one or more called parties. In accordance with the illustrative embodiment of the present invention, an anti-SPAM system receives signaling information for one or more telephone calls made to one or more called parties by a calling party. Although the calling party can be a human caller, in a SPAM-over-Internet-Telephony context the calling party can alternatively be a server or other network element that originates SPAM voice calls for advertising purposes; both possibilities are accounted for in the illustrative embodiment. The anti-SPAM system then observes the behavior of the called party or parties that is exhibited in response to receiving the telephone calls. Based on the observed behavior, the anti-SPAM system then updates one or more rules for handling future telephone calls made to the protected called parties.

Abstract: An apparatus and method are disclosed for detecting intrusions in Voice over Internet Protocol systems without an attack signature database. The illustrative embodiment is based on two observations: (1) various VoIP-related protocols are simple enough to be represented by a finite-state machine (FSM) of compact size, thereby avoiding the disadvantages inherent in signature-based intrusion-detection systems.; and (2) there exist intrusions that might not be detectable locally by the individual finite-state machines (FSMs) but that can be detected with a global (or distributed) view of all the FSMs. The illustrative embodiment maintains a FSM for each session/node/protocol combination representing the allowed (or “legal”) states and state transitions for the protocol at that node in that session, as well as a “global” FSM for the entire session that enforces constraints on the individual FSMs and is capable of detecting intrusions that elude the individual FSMs.

Abstract: An apparatus and method are disclosed for detecting intrusions in Voice over Internet Protocol systems, without the use of an attack signature database. In particular, the illustrative embodiment is based on the observation that some VoIP-related protocols (e.g., the Session Initiation Protocol [SIP], etc.) are simple enough to be represented by a finite-state machine (FSM) of compact size. A finite-state machine is maintained for each session/node/protocol combination, and any illegal state or state transition—which might be the result of a malicious attack—is flagged as a potential intrusion.

Abstract: A method and apparatus for automatically determining whether a security vulnerability alert is relevant to a device (e.g., personal computer, server, personal digital assistant [PDA], etc.), and automatically retrieving the associated software patches for relevant alerts, are disclosed. The illustrative embodiment intelligently determines whether the software application specified by a security vulnerability alert is resident on the device, whether the version of the software application on the device matches that of the security vulnerability alert, and whether the device's hardware platform and operating system match those of the security vulnerability alert.

Abstract: A method and apparatus for automatically determining whether a security vulnerability alert is relevant to a device (e.g., personal computer, server, personal digital assistant [PDA], etc.), and automatically retrieving the associated software patches for relevant alerts, are disclosed. The illustrative embodiment intelligently determines whether the software application specified by a security vulnerability alert is resident on the device, whether the version of the software application on the device matches that of the security vulnerability alert, and whether the device's hardware platform and operating system match those of the security vulnerability alert.

Abstract: A technique is disclosed that enables the run-time behavior of a data-processing system to be analyzed and, in many cases, to be predicted. In particular, the illustrative embodiment of the present invention comprises i) transforming the messages that constitute an unstructured log into a numerical series and ii) applying a time-series analysis on the resultant series for the purpose of pattern detection. Indeed, it is recognized in the illustrative embodiment that the problem really is to detect patterns that depict aspects of system behavior, regardless of the textual content of the individual log messages. In other words, by analyzing the totality of the messages in the log or logs—as opposed to looking for pre-defined patterns of the individual messages—system behavior can be mapped and understood. The mapping helps in characterizing the system for the purposes of predicting failure, determining the time required to reach stability during failure recovery, and so forth.

Abstract: A method for detecting intrusions that employ messages of two or more protocols is disclosed. Such intrusions might occur in Voice over Internet Protocol (VoIP) systems, as well as in systems in which two or more protocols support some service other than VoIP. In the illustrative embodiment of the present invention, a stateful intrusion-detection system is capable of employing rules that have cross-protocol pre-conditions. The illustrative embodiment can use such rules to recognize a variety of VoIP-based intrusion attempts, such as call hijacking, BYE attacks, etc. In addition, the illustrative embodiment is capable of using such rules to recognize other kinds of intrusion attempts in which two or more protocols support a service other than VoIP. The illustrative embodiment also comprises a stateful firewall that is capable of employing rules with cross-protocol pre-conditions.

Abstract: A method for detecting intrusions that employ messages of two or more protocols is disclosed. Such intrusions might occur in Voice over Internet Protocol (VoIP) systems, as well as in systems in which two or more protocols support some service other than VoIP. In the illustrative embodiment of the present invention, a stateful intrusion-detection system is capable of employing rules that have cross-protocol pre-conditions. The illustrative embodiment can use such rules to recognize a variety of VoIP-based intrusion attempts, such as call hijacking, BYE attacks, etc. In addition, the illustrative embodiment is capable of using such rules to recognize other kinds of intrusion attempts in which two or more protocols support a service other than VoIP. The illustrative embodiment also comprises a stateful firewall that is capable of employing rules with cross-protocol pre-conditions.

Abstract: A method is disclosed that enables the transmission of a digital message along with a corresponding information signal, such as audio or video. The supplemental information contained in digital messages can be used for a variety of purposes, such as enabling or enhancing packet authentication. In particular, a telecommunications device that is processing an information signal from its user, such as a speech signal, encrypts the information signal by performing a bitwise exclusive-or of an encryption key stream with the information signal stream. The device, such as a telecommunications endpoint, then intersperses the bits of the digital message throughout the encrypted signal in place of those bits overwritten, in a process referred to as “watermarking.” The endpoint then transmits the interspersed digital message bits as part of a composite signal that also comprises the encrypted information bits. No additional bits are appended to the packet to be transmitted, thereby addressing compatibility issues.

Abstract: A method is disclosed that enables the transmission of a digital message along with a corresponding media information signal, such as audio or video. A telecommunications device that is processing the information signal from its user, such as a speech signal, encodes the information signal by using a model-based compression coder. One such device is a telecommunications endpoint. Then, based on an evaluation of the perceptual significance of each encoded bit, or on some other meaningful characteristic of the signal, the endpoint's processor: (i) determines which encoded bits can be overwritten; and (ii) intersperses the digital message bits throughout the encoded signal in place of the overwritten bits. The endpoint then transmits those digital message bits as part of the encoded information signal. In this way, no additional bits are appended to the packet to be transmitted, thereby addressing the issue of compatibility with existing protocols and firewalls.

Abstract: A method is disclosed that enables the implementation of an embedded firewall at a telecommunications endpoint. In particular, the illustrative embodiment of the present invention addresses the relationship between the application, firewall engine, and packet-classification rules database that are all resident at the endpoint. In the variations of the illustrative embodiment that are described herein, the application: (i) directly communicates with the co-resident firewall engine such as through local message passing, (ii) shares memory with the firewall engine, and (iii) makes socket calls to the operating system that are intercepted by a middleware layer that subsequently modifies the rules database, depending on the socket call. The common thread to these techniques is that the application, firewall engine, and rules database are co-resident at the endpoint, which is advantageous in the implementation of the embedded firewall.

Abstract: A method is disclosed that enables the avoidance of a processor overload of a telecommunications endpoint device that is susceptible to traffic floods. An enhanced network switch sets the speed on one of its data ports as a specific function of the speeds of the devices that are connected to one or more of its other data ports. This behavior is different from that of network switches in the prior art, in which the data rate of a port in the prior art is auto-negotiated to the highest speed that can be supported by the network elements at either end of the port's connection, regardless of the other devices present. By considering the specific devices that are connected, the enhanced network switch is able to limit the amount of traffic that is directed by an upstream device, such as a router, towards a device with limited processor capability, such as a packet-based phone.

Abstract: A method is disclosed that enables mitigating at least some of the problems caused by a packet attack. When a first Internet Protocol (IP)-capable device is subjected to a packet attack, it indicates periodically to a second IP-capable device that certain communications with the first device are to be suspended. The periodic transmitting of the indication is performed at a slower rate than the keep-alive mechanism that is normally used to detect loss of connectivity. When the second device receives the transmitted indication, it refrains from transmitting keep-alive messages to the first device for a predetermined interval. Meanwhile, the first device also refrains from transmitting keep-alive messages to the second device for a similar interval. In transmitting the suspend indication, the illustrative embodiment seeks to prevent pairs of communicating devices that are experiencing packet attacks from continuing their operation under the erroneous assumption that each device is unavailable.

Abstract: A method for Real-time Transport Protocol (RTP) packet authentication on a packet data network. In particular, the invention relates to a method for preventing toll fraud, privacy compromise, voice quality degradation, or denial of service (DoS) on Voice over IP networks. The Real-time Transport Protocol (RTP) is susceptible to several security attacks, including thirdparty snooping of private conversations, injection of forged content, and introduction or modification of packets to degrade voice quality. The Secure Real-time Transport Protocol (SRTP) provides confidentiality, message authentication, and replay protection for RTP traffic. However, SRTP incurs an additional overhead to verify the HMAC-SHA1 message authentication code for each packet. SRTP+ significantly decrease the verification overhead compared to SRTP and thereby increases the number of faked packets required to mount a successful denial of service attack. SRTP+ provides packet authentication but not integrity.

Abstract: A method of authenticating a communications between a sender and a receiver includes agreeing, by a sender and receiver, on a shared secret, computing a first sequence of numbers at the sender using the shared secret, and computing a second sequence of numbers at the receiver using the shared secret. Successive values of the first sequence are respectively embedded in successive messages by the sender. Upon receiving a message, the receiver compares the embedded value of the first sequence with a list of values including at least one corresponding value from the second sequence and the received message to considered to originate from an authentic sender if the value of the first sequence matches the value of the second sequence. The method value is removed from a list of values in the second sequence for comparing.

Abstract: A method of transporting authentication information in a media stream packet includes embedding the authentication information in one of a heading and a payload of the media stream packet.

Abstract: A method and apparatus for executing target application programs with employment of a supervisor that is coupled to the executing target application through a conventional status reporting port of the computer. Events that represent execution errors or unexpected behavior are provided to the reporting port, or discovered through the reporting port, and the supervisor responds to such events by perusing a configuration that is tailored to the executing target application. For each reported event, the supervisor retrieves one or more actions that the configuration file specifies for the reported events and executes the specified actions. The configuration file includes actions that aim to effect a recovery, from reported events, including restart application, or a thread of the application, based on checkpointed data, restart target application as soon as it becomes idle, and suspend a thread when a thread starvation condition exists.

Abstract: High levels of treated fumed silica, processing fluid and high molecular weight silicone polymer are continuously compounded into a homogeneous silica filled heat-vulcanizable silicone composition by forming a premix in a continuous annular layer mixer and continuously discharging the premix into a compounding apparatus for compounding to form the filled heat-vulcanizable silicone composition.

Abstract: A method for preventing or limiting the effects of Denial-of-Service attacks in a communication appliance having a packet-classification rule base which allows all legitimate packets to be forwarded to the communication appliance includes monitoring incoming packets to the communication appliance to determine whether conditions indicating a Denial-of-Service attack are present. If a Denial-of-Service attack is present, a rule base subset of the packet-classification rule base is selected from a plurality of rule base subsets based on a current one of a plurality of operating states of the communication appliance.

Abstract: Fault tolerance is improved in a computing system which includes one or more computing machines by (i) executing a control thread or other control program in conjunction with a fault tolerance software system running on at least one of the machines, and (ii) initiating via the control program a test script program which sends one or more requests to a monitored program. The test script program also processes corresponding responses to the one or more requests, and generates a return value utilizable by the control program to indicate a failure condition in the monitored program. The computing system may be configured in accordance with a client-server architecture, with the fault tolerance software system and the monitored program both running on a server of the system.