Alcatel Lucent

Kedar S Namjoshi

Gordon Thomas Wilfong

Pramod V Koppol

Eric Jonathan Bauer

Randee Susan Adams

Daniel Weiler Eustace

Lyle Dean Kipp

Girija Narlikar

Thanos Stathopoulos

Christopher L Conway

Dennis R Dams

Athanasios Stathopoulos

Athansios Stathopoulos

Pramod Koppol

The backup-in-the-middle primary-backup configuration is created by placing a backup-in-the-middle forwarder in the routing path between the primary and the environment. The backup-in-the-middle forwarder intercepts output messages along with required state information sent by the primary to the environment. The backup-in-the-middle forwarder backs up the primary by updating its state information and forwards the output packets to the environment.

Method and apparatus for in the middle primary backup replication

Various exemplary embodiments relate to a method of preventing extreme coresidency hazards among application instances in a cloud network. The method includes determining a first failure group of a first instance of an application; establishing a connection with a second instance of a peer application; determining a second failure group of the second instance; comparing the first failure group to the second failure group; and establishing a second connection with a third instance of the peer application if the first failure group and the second failure group share a failure point.

Preventing extreme coresidency hazards in cloud computing

A system, method, apparatus and mechanism for estimating worst-case time complexity of a regular expression defining a pattern adapted for identifying malicious packets and comprising one or more back-references (backref-regex) by constructing a non-deterministic finite automaton (NFA) corresponding to the backref-regex (backref-NFA), wherein the backref-NFA comprises a plurality of NFA-states and a respectively labeled edge for each of the one or more back-references of the backref-regex; performing liveness analysis on the backref-NFA to determine for each NFA-state of the backref-NFA a set of back-references alive at the NFA-state; and determining a maximum number of alive back-references over the plurality of NFA-states, wherein the determined maximum number is indicative of the worst-case time complexity of the backref-regex.

Method and apparatus for pattern matching for intrusion detection/prevention systems

A primary-backup replication capability is disclosed. A primary process and a backup process participate in a synchronization process configured to synchronize state information of the primary and backup processes. The synchronization process operates in periods of time referred to as epochs. During the current epoch, the primary process computes state update information representing changes to the state information of the primary process since a previous epoch, and also buffers output messages generated during the current epoch in an associated output buffer dedicated for use in the current epoch. The primary process initiates a new epoch independent of receiving, from the backup process, a state update acknowledgement for the previous epoch. The output messages buffered for the current epoch are released from the associated output buffer after the primary process receives a state update acknowledgment for the current epoch and all output buffers of all previous epochs are empty.

Method and apparatus for synchronization in primary-backup replication schemes

The method includes determining a timestamp corresponding to a received data packet associated with the virtual machine and releasing the data packet from a buffer based on the timestamp and a time another data packet is released from the buffer.

Time-preserved transmissions in asynchronous virtual machine replication

Methods and apparatus are provided for incremental analysis of one or more properties of a program. According to one aspect of the invention, at least one property of a software program is evaluated, given one or more changes to the software program. Nodes in a derivation graph are identified corresponding to changed edges in a control flow graph representation of the software program, wherein the derivation graph describes an earlier evaluation of the software program. In addition, at least one of the identified nodes in the derivation graph is updated and the derivation graph is traversed outward from a location of a change. The revised derivation graph can optionally be further processed to remove false errors.

Method and apparatus for incremental analysis of one or more properties of a program

A packet is compared to a pattern defined by a regular expression with back-references (backref-regex) in a single pass of a non-deterministic finite automaton corresponding to the backref-regex (backref-NFA) that includes representations for all backref-regex's back-references. The packet's characters are sequentially selected and analyzed against the backref-NFA until a match or no-match between the packet and pattern is determined. Upon selecting a character, a corresponding configurations-set is updated, where the set includes configurations associated with respective NFA-states of the backref-NFA and indicating whether the selected character is being matched against a back-reference. With the configurations-set being updated the comparison process proceeds along backref-NFA's NFA-states. The updated configurations-set includes configurations associated with NFA-states reachable from the configurations in the pre-updated set. When the configurations-set includes a final state, a match is determined. When the configurations-set becomes empty, or upon selection of all characters lacks the final state, a no-match is determined.

Growing community of inventors

Backing Ridge, NJ, United States of America

Kedar S Namjoshi