Arbor Networks, Inc.

A computer method and system for determining patterns in network traffic packets having structured subfields for generating filter candidate regular expressions for DDoS attack mitigation. Stored packets are analyzed to extract a query name for each stored packet. Each query name is segregated into subfields. A Results-table is generated utilizing the segregated subfields of the query names. A Field-length table is generated that contains the length of the Field Values (Field-length) for each Field Name and an associated counter indicating how many instances the Field-length for a Field Name is present in the extracted query names. The Field-length table is analyzed to determine patterns of equal length in the “Results” table. Utilizing the Patterns table, unique combinations of the Field Values are generated as a filter candidate regular expression for DDoS attack mitigation purposes.

A method includes receiving summary messages summarizing respective aggregated traffic metadata packets output from the at least one traffic management device and an engine. Each summary message identifies an origination pair having a traffic management device and an aggregation engine and a sequence number. The method further includes tracking per subinterval of a series of sub-intervals, highest and lowest sequence numbers and a count of summary messages received for each unique origination pair from the beginning of the subinterval. The method further includes accumulating, per interval, accumulated highest and lowest sequence numbers and an accumulated count of summary messages for each unique origination pair from the beginning of the interval and for all previous subintervals for tracking dropped aggregated traffic metadata packets for the interval. The method further includes estimating a number of dropped aggregated traffic metadata packets for the interval based on the accumulated highest and lowest sequence numbers and the count of summary messages.

A computer method and system for determining a threat level score for a detected network attack. Network data is received having a detected network attack, which is then analyzed to determine metadata associated with the network attack. The determined metadata associated with the network attack is analyzed to determine: 1) an attack objective component; 2) an attack method component; and 3) an attack execution component, each being associated with the network attack. A severity score value for the network attack is then determined based upon calculating a weighted value for each of the: 1) an attack objective component; 2) a attack method component; and 3) an attack execution component. And an alert signal/message is then generated for a network attack based upon the determined severity score value.

A method of monitoring a network during a DDoS attack is provided. The method includes receiving packets included in the attack, determining whether the packets are designated for tarpitting, for each packet from a source determined to be designated for tarpitting, assigning the packet to an existing or newly established flow, applying at least one tarpitting technique, and applying a randomization function for adjusting the at least one tarpitting technique or for selecting the at least one tarpitting technique to be applied from a plurality of candidate tarpitting techniques.

A computer implemented method system for obscuring the status of a network service provided by a network device. Received in a network monitoring device is network packet request message intended for a network device. The network monitoring device analyzes the received network packets request to determine whether the received network packet request is a DDoS network probe packet request. If the received packet request was determined to be a DDoS network probe packet requests, a response is generated and sent from the network monitoring device to the device that sent the DDoS network probe packet request indicating a faux degradation of service level for the intended network device.

An authenticating method including storing internally a reference hash set having hashes of genuine client binary and/or library files. The method further includes receiving an authentication request for authentication of the client process to authorize the client process to access a server resource provided by the server process. In a first phase, the method further includes requesting from the client OS, the process details and the hashes of the client binary and/or library files and verifying (using the reference hash set) these hashes received. In a second phase the method further includes, contingent on positive verification in the first phase, transmitting a random message to the client process by locating it using the IP address and PID presented during the authentication request, verifying a copy of the random message received back from the client process, and contingent on positive verification in the second phase, allowing the client process to access the requested server resource.

An upstream network bridge connection request is received in a network device from first network component for connecting to a second network component. This upstream network bridge connection request is analyzed by the network bridge to determine if a network attack threat is associated with the client device requesting the upstream network bridge connection to the server device preferably by inspecting certain network metrics present in the downstream connection associated with the client device. If no, then a determination is made as to whether a preexisting upstream network bridge connection between the client device and the server device exists in a connection pool database. If yes, then the preexisting upstream network bridge connection is retrieved from the connection pool database and is implemented for creating an upstream network connection between the client and server devices.

A system and computer-implemented method to detect particular Domain Name System (DNS) misuse, wherein the method includes obtaining monitored network data. The monitored network data includes respective instances of request traffic. The request traffic is associated with DNS requests that request resolution of a name that belongs to at least one identified domain. Each DNS request is sent from a source address of one or more stub resolver; the source address of the stub resolver may be spoofed. Each instance of request traffic includes the source address, the name for which DNS resolution is requested to be resolved, and the at least one identified domain associated with a corresponding DNS request. The method further includes tracking over time, using a probabilistic algorithm, an approximation of a first cardinality of names belonging to a selected domain of the at least one identified domain included in the instances of request traffic. The method further includes tracking over time, using the probabilistic algorithm, an approximation of a second cardinality of source addresses associated with the selected domain included in the instances of request traffic. The method further includes detecting a combination of a first condition of the approximation of the first cardinality and the second condition of the approximation of the second cardinality, wherein the combination of the first and second conditions indicates the occurrence of a specific DNS misuse. The method further includes performing an action to at least one of output a notification of and correct a condition associated with the detected occurrence of the specific DNS misuse.

A method of detecting patterns in network traffic is provided. The method includes receiving packets of network traffic, performing a frequency analysis per field of the packets as a function of frequency of the occurrence of the same data in the corresponding field, and selecting top values which are values associated with each field of the set of fields that satisfy a criterion as having occurred most frequently in the packets as a function of a result of the frequency analysis. The method further includes assigning a bit encoding scheme that uses variable bit encoding to encode each of the top values for each field that has a top value, encoding into a single value each packet of the packets based on a bitfield representation that uses the encoding scheme for values associated with each field that has a top value, storing each potential combination of fields of the set of fields being processed, with all bits set per field when the field is an active field and no bits set when the field is inactive, performing a bitwise operation on each encoded packet with the stored potential combinations, sorting the results of the bitwise operation based on a number of the active fields and a number of occurrences of each same result of the bitwise operation, and providing the results of the sorting to a mitigation device for determining whether an attack is underway and/or for filtering network traffic for mitigating an attack.

A method and apparatus for processing flow specification (Flowspec) messages to one or more of a plurality of customer networks by a controller device coupled to the plurality of customer networks. Preferably a network controller monitors network traffic flowing through each of the customer networks for detecting a network attack in one of the plurality of customer networks, via monitoring of the network traffic. Upon detection of a network attack, a Flowspec message is generated for the customer network detected to be under network attack wherein the Flowspec message is configured specifically for that customer network. The generated Flowspec message is transmitted to the customer network detected to be under network attack for implementation by the customer network for mitigation of the detected network attack.