John David Dunagan

US Patent:

7155420, Dec 26, 2006

Filed:

Apr 30, 2003

Appl. No.:

10/426669

Inventors:

John Dunagan - Sammamish WA, US
Santosh S. Vempala - Cambridge MA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

G06F 17/00

US Classification:

706 15, 706 17, 706 19, 706 21, 708446

Abstract:

In one embodiment, a system and method for solving linear programs includes a perceptron algorithm configured to move toward a solution to the linear program. A transform algorithm is configured to stretch portions of a vector space within which the linear program is defined. A decision module decides between continued application of the perceptron algorithm and application of the transform algorithm based on a rate at which the approximate solutions are approaching a satisfactory solution.

US Patent:

7376121, May 20, 2008

Filed:

Jun 6, 2003

Appl. No.:

10/455877

Inventors:

John David Dunagan - Sammamish WA, US
Jiahe Wang - Issaquah WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

H04L 12/28

US Classification:

370351

Abstract:

Disclosed is a routing and bandwidth allocation system that maximizes network throughput while maintaining global fairness in the sharing of network resources. From gathered global network information (such as inter-node communications patterns and network topology), routing tables and bandwidth allocation policies are computed for routers. In some embodiments, the computations involve applying multi-commodity flow methods to provide a “max-fair” allocation of network resources. While in some embodiments each router collects global network information and then locally produces its own routing and bandwidth allocation tables, it can be simpler and cheaper in terms of both computation and security for a centralized, trusted control unit to perform the calculations and then to distribute the results to the routers. The computed bandwidth policies can leave some bandwidth unallocated to handle unexpected surges in demand. The computed routing tables can include multiple paths leading to greater link utilization and to robustness to link failure.

US Patent:

7379447, May 27, 2008

Filed:

Sep 23, 2004

Appl. No.:

10/947838

Inventors:

John D. Dunagan - Bellevue WA, US
Paramvir Bahl - Sammamish WA, US
Ranveer Chandra - Ithaca NY, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

H04J 3/06
H04B 1/00
H04B 5/00
H04B 7/00

US Classification:

370350, 375134, 370324, 370338, 370329, 455 411, 455 412, 455 413

Abstract:

A system and method that increases the capacity of a wireless network using frequency diversity. A user switches between channels of a network using a single network interface card in such a manner that nodes desiring to communicate overlap while disjoint communications mostly do not overlap. A driver is inserted into a device's networking stack and controls the network interface card using a plurality of virtual wireless network adapters. Packets for a recipient are queued when the recipient is not accessible on the node's channel. In one embodiment where multiple nodes are switching in and out of channel, the method changes part of a nodes channel hopping schedule to ensure concurrent connectivity in a channel for at least a brief time period such that packets can be received/transmitted with desired nodes.

US Patent:

7551552, Jun 23, 2009

Filed:

Oct 17, 2003

Appl. No.:

10/686658

Inventors:

John Dunagan - Bellevue WA, US
Nicholas J. A. Harvey - Cambridge MA, US
Michael B. Jones - Redmond WA, US
Dejan Kostić - Durham NC, US
Marvin M. Theimer - Bellevue WA, US
Alastair Wolman - Seattle WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

H04J 1/16

US Classification:

370221, 370242, 370256

Abstract:

A guaranteed distributed failure notification method is described, wherein a failure notification (FN) facility allows applications using the facility to create FN groups to which the application associates an application state. The application registers failure handlers with the FN facility on nodes in the FN group; each failure handler is associated with a specific FN group. When, on a given node, the FN facility learns of a failure in the FN group, the facility executes the associated failure handler on that node. System failures detected by the application are signaled to other FN group members using the facility. The facility detects system failures that occur in an overlay network on which the facility is implemented, and signals a failure notification to the other FN group members.

US Patent:

7614046, Nov 3, 2009

Filed:

Nov 24, 2004

Appl. No.:

10/997685

Inventors:

Bradford Ruffin Daniels - Redmond WA, US
John Dunagan - Bellevue WA, US
Roussi A. Roussev - Melbourne FL, US
Chad E. Verbowski - Redmond WA, US
Yi-Min Wang - Bellevue WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

G06F 9/44

US Classification:

717170, 717168, 717171, 717127, 717128, 717131

Abstract:

A method and system for analyzing the impact on software of an update to a software system is provided. The impact analysis system identifies resources that are affected by an update to the software system and identifies resources that are accessed by various software components during execution of the software components. To analyze the effects of an update, the impact analysis system identifies those accessed resources of the software components that are affected by the update as being impacted resources. The impact analysis system considers those software components that access the impacted resources to be impacted software components. The impact analysis system provides a user interface through which a user can view and analyze the impact of an update.

US Patent:

7620995, Nov 17, 2009

Filed:

Aug 29, 2005

Appl. No.:

11/214131

Inventors:

Chad E Verbowski - Redmond WA, US
John D. Dunagan - Sammamish WA, US
Shuo Chen - Urbana IL, US
Yi-Min Wang - Bellevue WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

G06F 7/04
G06F 17/30

US Classification:

726 27, 726 26, 726 9, 713165, 713167

Abstract:

A technique for identifying dependencies of an application upon a given security context includes monitoring security checks generated by the application. The security checks requiring elevated rights are identified and the state of execution of the application corresponding to the identified security checks may be logged. The security checks requiring elevated rights may be identified by monitoring access checks, monitoring privilege checks, checking user/group identifiers against a list of known identifiers associated with elevated rights, or the like.

US Patent:

7650317, Jan 19, 2010

Filed:

Dec 6, 2006

Appl. No.:

11/567328

Inventors:

Sumit Basu - Seattle WA, US
Karthik Gopalratnam - Mountain View CA, US
John David Dunagan - Bellevue WA, US
Jiahe Helen Wang - Issaquah WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

G06F 15/18

US Classification:

706 12

Abstract:

An active learning framework is provided to extract information from particular fields from a variety of protocols. Extraction is performed in an unknown protocol, in which the user presents the system with a small number of labeled instances. The system then automatically generates an abundance of features and negative examples. A boosting approach is then used for feature selection and classifier combination. The system then displays its results for the user to correct and/or add new examples. The process can be iterated until the user is satisfied with the performance of the extraction capabilities provided by the classifiers generated by the system.

US Patent:

7716530, May 11, 2010

Filed:

Dec 5, 2006

Appl. No.:

11/567113

Inventors:

Chad Verbowski - Redmond WA, US
Brad Daniels - Redmond WA, US
John Dunagan - Bellevue WA, US
Shan Lu - Hefei, CN
Roussi Roussev - Melbourne FL, US
Juhan Lee - Issaquah WA, US
Arunvijay Kumar - Sammamish WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

G06F 11/00

US Classification:

714 37, 714 33, 714 34, 714 38, 714 45, 717130

Abstract:

Apparatus and methods for intercepting and analyzing threads are disclosed. In one embodiment, a thread data recorder is configured to instrument one or more existing functions by modifying computer executable instructions in the functions to intercept threads calling the functions. In one possible implementation, the number of existing functions instrumented can be reduced by instrumenting choke point functions. The instrumented functions can also capture data associated with the threads as the threads execute at the function. This data can be saved to memory and compressed into logs. In one aspect, the data can be saved and/or compressed at a time when processor resources are being used at or below a predetermined level. The captured data can be used to analyze a functioning of a computer system in which the threads were produced.