Arbor Networks, Inc.

University of California

Microsoft Technology Licensing, LLC

Stefan Roberts Savage

Thomas E Anderson

David Wetherall

Sumeet Singh

George Varghese

Cristi Estan

Fang Yu

Martin Abadi

Yinglian Xie

Geoffrey Michael Voelker

Andreas Pitsillidis

A system to automatically classify types of IP addresses associated with a user. Information, such as user names, machine information, IP address, etc., may be obtained from logs. For each user or host in the logs, home IP addresses are identified from IP addresses where the user or host shows a predetermined level of activity. Travel IP addresses are identified, which are IP addresses at locations greater than a predetermined distance from the home IP addresses, as determined from geolocation data. A pattern analysis may be performed to determine which of the home IP addresses are work IP addresses associated with the user or host. The system may thus provide a classification of a user's or host's associated IP addresses as being one of travel, home, and work IP addresses. From this classification, mobility patterns may be derived, as well as applications to enhance security, advertising, search and network management.

Automatic identification of travel and non-travel network addresses

An apparatus is equipped to receive network traffic data for network traffic routed over one or more network links relevant to a network link. Selected numbers of analysis are performed to determine if the network link of interest is being misused. The analyses include but are not limited to analyses to determine whether the network traffic routed are inconsistent with an expected traffic pattern, whether unallocated source addresses are present, whether source addresses exhibit an uncharacteristic even distribution pattern, whether a server is uncharacteristically excessive in responding to the same source address, whether normal bursty behavior is absent from the traffic, whether a ratio of packets in one direction to packets in another direction is out of balance, whether a ratio of packets of one type to packets of another type is out of balance, and whether a server is uncharacteristically excessive in responding with error responses.

Detecting network misuse

Network worms or viruses are a growing threat to the security of public and private networks and the individual computers that make up those networks. A content sifting method if provided that automatically generates a precise signature for a worm or virus that can then be used to significantly reduce the propagation of the worm elsewhere in the network or eradicate the worm altogether. The content sifting method is complemented by a value sampling method that increases the throughput of network traffic that can be monitored. Together, the methods track the number of times invariant strings appear in packets and the network address dispersion of those packets including variant strings. When an invariant string reaches a particular threshold of appearances and address dispersion, the string is reported as a signature for suspected worm.

Detecting public network attacks using signatures and fast content analysis

A server, using a deterministic function, a secret value and persistent information of a packet, destined for a client device, generates and includes a conversation identifier for inclusion with the packet. The client device in turn includes the conversation identifier in a subsequent packet sent by the client device destined for the server. An intermediate routing device having knowledge of the deterministic function and the secret value, upon receiving the packet en-route from the client device to the server, would independently determine whether the packet is a part of a conversation between the client and the server, by independently verifying the included conversation identifier, and forward or not forward the packet accordingly. As result, undesirable packets may be independently detected and filtered for the server.

Independent detection and filtering of undesirable packets

The present invention provides for a novel approach to protecting a system owner's system(s) from being exploited and providing involuntary assistance to a DOS attack. The present invention provides the protection by detecting and preventing undesirable or inappropriate network traffic from being sourced from a network domain. More specifically, a monitor/regulator is provided to monitor network traffic leaving a network domain. The monitor/regulator determines if undesirable/inappropriate network traffics are leaving the network domain based on the observed characteristics of the outbound and inbound network traffics. If it is determined that undesirable/inappropriate network traffics are leaving the network domain, the monitors/regulator, in one embodiment, at least warns system owners of the detection. In another embodiment, the monitors/regulator further issues regulation instruction(s) to boundary routing device(s) of the network domain(s), thereby preventing the network domain(s) from being exploited to source such undesirable/inappropriate network traffics.

Detecting and preventing undesirable network traffic from being sourced out of a network domain

Detecting attacks against computer systems by automatically detecting signatures based on predetermined characteristics of the intrusion. One aspect looks for commonalities among a number of different network messages, and establishes an intrusion signature based on those commonalities. Data reduction techniques, such as a hash function, are used to minimize the amount of resources which are necessary to establish the commonalities. In an embodiment, signatures are created based on the data reduction hash technique. Frequent signatures are found by reducing the signatures using that hash technique. Each of the frequent signatures is analyzed for content, and content which is spreading is flagged as being a possible attack. Additional checks can also be carried out to look for code within the signal, to look for spam, backdoors, or program code.

One or more networking apparatuses are employed to practice a networking method that improves a first networking device's likelihood in meeting its service level goals/commitments for a first group of network traffic serviced by the first networking device. Determination is made, away from the networking device, on whether the first network device is meeting the service level goals/commitments for the first group of network traffic. Determination may include monitoring the first group of network traffic at or away from the networking device. If the service level goals/commitments are not being met, a second group of network traffic (also serviced by the first networking device) is regulated. Regulation may be made at the networking device or away from the network device. Additionally, if the condition for regulation is no longer presents, regulation may be moderated or removed. Further, the service level goals/commitments may include reliability and/or performance goals/commitments.

Distributed service level management for network traffic

A director is provided to receive source address instances of packets routed through routing devices of a network. The director determines whether any of the reported source address instances are to be deemed as spoof source address instances. The director further determines where filtering actions are to be deployed to filter out packets having certain source addresses deemed to be spoof instances. The director makes its determinations based at least in part on a selected one of a number of consistency measures. The consistency measures may include but are not limited to spatial consistency, destination consistency, migration consistency, and temporary consistency. The consistency measures are evaluated using spatial, destination source address range, migration and timing S/D/M/T distribution profiles of the reported source addresses. In some embodiments, the determinations are based further in view of reference S/D/M/T distribution profiles, which may be an exemplary S/D/M/T distribution profile of a typical non-spoof source address or a historical S/D/M/T distribution profile of the source address.

Network traffic regulation including consistency based detection and filtering of packets with spoof source addresses

A number of sensors are distributively deployed in a network, either integrally disposed in a number of routing devices of the network or externally disposed and coupled to the routing devices, to monitor and report on network traffic routed through the routing devices. A director is provided to receive network traffic reports from the sensors for the routing devices, and to determine whether moderating actions are to be taken to moderate an amount of network traffic, based at least in part on some of the network traffic reports received from the sensors. In one embodiment, upon determining moderating actions are to be taken, the director further determines what kind of moderating actions are to be taken, including where the moderating actions are to be taken. In one embodiment, the director further instructs appropriate ones of the sensors to cause the desired moderating actions to be applied on the network traffic going through some of the routing devices. In one embodiment, the director, in cooperation with the sensors, also determines when and where moderating actions are to be relaxed, and causes such relaxation to be effectuated. In yet another embodiment, the director, in cooperation with the sensors, also determines when and where regulating actions filtering out certain types of network traffic destined for a network node are to be applied, and causes such filtering to be performed.

Distributed solution for regulating network traffic

An apparatus is equipped to receive network traffic data for network traffic routed through a number of routing devices with one or more degrees of separation from a network node. The network traffic data include at least network traffic data for network traffic destined for the network node which meet a traffic type selection criteria and are routed by the routing devices to the network node. The apparatus is further equipped to progressively regulate and de-regulate network traffic routing by the routing devices based at least in part on the received network traffic data and the degrees of separation of the routing devices from the network node. Regulation extends from routing devices with the lowest degree of separation from the network node to routing devices with the highest degree of separation, following in the reverse direction of the routing paths traversed by the packets to reach the network node. In one embodiment, the extension or push back is made one degree of separation at a time. In one embodiment, deregulation follows the reverse path, whereas in another embodiment, deregulation is determined and implemented locally, whenever regulation or the extent of regulation is no longer needed. In one embodiment, regulation is made in accordance with a not-to-exceed profile, and the not-to-exceed limit or limits are divided up as regulation extends away from the network node.

Growing community of inventors

Carlsbad, CA, United States of America

Stefan Roberts Savage