Richard Powell Draves

US Patent:

6349355, Feb 19, 2002

Filed:

Feb 6, 1997

Appl. No.:

08/795591

Inventors:

Richard P. Draves - Seattle WA
Scott Cutshall - Carnation WA
Gilad Odinak - Bellevue WA

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

G06F 1200

US Classification:

711 6, 711203

Abstract:

A computer system has a microprocessor that can execute in a non-privileged user mode and a privileged kernel mode. A user virtual address space is used when the microprocessor is in the user mode, and a kernel virtual address space is used when the microprocessor is in the kernel mode. Each of the address spaces has the same range of virtual addresses that is designated for shared components. The user virtual address space is mapped to an offset position within the kernel address space. When a user process calls a kernel function with a pointer argument, the pointer is biased before being dereferenced to account for the offset of the user address space within the kernel address space. This allows for sharing of position-dependent code, while still allowing the kernel to access the entire user address space.

US Patent:

6385649, May 7, 2002

Filed:

Nov 6, 1998

Appl. No.:

09/188014

Inventors:

Richard P. Draves - Seattle WA
Christopher Kevin King - Somerville MA
Srinivasan Venkatachary - St. Louis MO

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

H04L 1228

US Classification:

709224, 709220, 370392

Abstract:

A method for compressing a routing table involves constructing a binary tree representation of the routing table. The compression method makes three passes through the tree. In a first pass, the compression method propagates routing information down to the tree leaves. During this pass, the program assigns every leaf node in the tree an associated next hop or an inherited next hop from a higher level ancestral node. In a second pass, the compression method migrates prevalent next hops up the tree. This bottom up pass involves forming a set of next hops at a parent node by supernetting the sets of next hops A and B for a pair of child nodes corresponding to the parent node, according to the following operation: where A*B is a set of next hops formed at the parent node. In the third pass, the compression method eliminates redundant branches in the tree. This top down pass begins at a parent node and selects a next hop from a parent node.

US Patent:

6405262, Jun 11, 2002

Filed:

Jul 14, 1995

Appl. No.:

08/502376

Inventors:

Keith R. Vogel - Duvall WA
Richard P. Draves - Seattle WA
Paul J. Leach - Seattle WA

Assignee:

Microsoft Corporation - Redmond CA

International Classification:

G06F 944

US Classification:

709315, 709203

Abstract:

A computer system includes a plurality of client processes executing in respective address spaces and at least one server process executing in a different address space than the client processes. The server process has one or more available server objects for potential use by the client processes. The server objects are accessible by the client processes through a plurality of server object interfaces dynamically created in response to demand for said interfaces by the client processes. The server object interfaces are destroyed when there is no further demand for them. Each object interface can be simultaneously held for use during at least a portion of its lifetime by more than one of the client processes. The computer system further includes one or more client-side ping managers and at least one server-side ping manager. Each client process registers interfaces it is holding for use with an associated client-side ping manager.

US Patent:

6760909, Jul 6, 2004

Filed:

Jul 14, 1998

Appl. No.:

09/115448

Inventors:

Richard P. Draves - Seattle WA
Gilad Odinak - Redmond WA

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

G06F 900

US Classification:

718102

Abstract:

A virtual memory system includes a hardware-implemented translation lookaside buffer (HTLB) as well as a software-implemented translation lookaside buffer (VTLB). The VTLB is in the systems unmapped memory. The system further includes a plurality of address maps, corresponding to an operating system kernel and to individual tasks executing within the system. The kernel has an address space which includes both mapped and unmapped memory. The address maps corresponding to the individual tasks are stored in the mapped memory of the kernels address space. The address map corresponding to the kernel itself, however, is stored in the kernels unmapped memory. HTLB misses are handled by referring to the VTLB. VTLB misses are handled by referring to an appropriate one of the address maps. The code for handling these misses resides in unmapped memory of the kernels address space.

US Patent:

20020007389, Jan 17, 2002

Filed:

Jul 18, 2001

Appl. No.:

09/909072

Inventors:

Michael Jones - Redmond WA, US
Paul Leach - Seattle WA, US
Richard Draves - Seattle WA, US
Joseph Barrera - Belmont CA, US

Assignee:

Microsoft Corporation

International Classification:

G06F009/00

US Classification:

709/104000

Abstract:

A resource management mechanism is provided to ensure that real-time application programs running on a single machine or set of machines exhibit predictable behavior. The resource management mechanism employs the abstraction of an activity which serves as the basis for granting resource reservations and for accounting. An activity submits a request for resources in specified amounts to a resource planner. The activity is resource self-aware so that it is aware of its resource requirements. The activity may query resource providers to obtain resource requirements for particular operations. The resource planner determines whether the activity should be granted the requested reservation by employing an internal policy. Policy is separated by mechanism so that the resource planner may implement any of a number of policies. The resource planner may choose to grant the reservation to an activity or deny the request by an activity. When denying a request, the resource planner may inform the activity of what quantity of the requested resources are currently available so that the activity may submit a modified request. The resource management mechanism includes a dynamic feedback mechanism for initiating renegotiation of resource reservations when appropriate.

US Patent:

20040264503, Dec 30, 2004

Filed:

Jun 30, 2003

Appl. No.:

10/610397

Inventors:

Richard Draves - Seattle WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

H04J003/16

US Classification:

370/469000

Abstract:

Disclosed is a virtual protocol “interlayer” between two protocol layers in a communications stack. When a communications task needs to be performed, but implementation within the existing protocol layers may hinder deployment due to issues of compatibility, the methods of the present invention are used to create an interlayer to handle the task. An addressing scheme peculiar to the interlayer is set up. The interlayer frees the other layers in the protocol stack to operate as before, leaving to the interlayer the specifics of performing the communications task. In one embodiment, an interlayer is built between the ISO/OSI protocol layers 2 and 3. Source routing is performed within this interlayer, using interlayer addresses. By using interlayer addresses rather than layer 2 or layer 3 addresses, this embodiment of source routing allows compatibility both with multiple layer 3 protocols and with multiple layer 2 network interfaces.

US Patent:

20050185632, Aug 25, 2005

Filed:

Feb 23, 2004

Appl. No.:

10/784687

Inventors:

Richard Draves - Seattle WA, US
Brian Zill - Redmond WA, US
Jitendra Padhye - Kirkland WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

H04L012/28

US Classification:

370351000

Abstract:

Systems and methods for routing packets by nodes in an ad hoc network in accordance with a link quality source routing protocol are disclosed. Route discovery, route maintenance, and metric maintenance are designed to propagate and keep current link quality measurements. Metric maintenance includes a reactive approach for links that a node is currently using to route packets, and a proactive mechanism for all links. Nodes are configured to include a send buffer, a maintenance buffer, a request table, link quality metric modules, and preferably a neighbor cache and a link cache. The invention allows for asymmetric links in the network. The invention may be implemented within a virtual protocol interlayer between the link and network layers. The invention may employ any particular link quality metrics, including metrics based on probing techniques as well as metrics based on knowledge gained in other ways.

US Patent:

20050286426, Dec 29, 2005

Filed:

Mar 15, 2005

Appl. No.:

11/081120

Inventors:

Jitendra Padhye - Redmond WA, US
Richard Draves - Seattle WA, US
Brian Zill - Redmond WA, US

Assignee:

Microsoft Corporation - Redmond WA

International Classification:

H04L012/26
H04L012/28

US Classification:

370238000, 370400000, 370351000

Abstract:

A system and method for link quality routing uses a weighted cumulative expected transmission time path metric. A system for routing in a multi-hop ad hoc network, and a method for measuring the link quality of a route in the network, include assignment of a weight to a link in accordance with an expected transmission time of a packet over the link, and a combining of individual link weights for a route into a path metric. The path metric accounts for interference among links that use a shared channel. In the calculation of the path metric, the expected transmission times of links that interfere with one another are added, while the expected transmission times for non-interfering links are considered separately.