Akamai Technologies, Inc.

Massachusetts Institute of Technology

Microsoft Technology Licensing, LLC

Emerald Innovations, LLC

Hariharan Rahul

Ravi Sundaram

Dina Katabi

F Thomson Leighton

Srikanth Thirumalai

Jay Parikh

Matthew S Levine

Adrian Soviani

Swarun Suresh Kumar

Robert D Kleinberg

Bruce Maggs

Rizwan S Dhanidina

Yoav O Yerushalmi

Paramvir Bahl

Ranveer Chandra

Thomas Moscibroda

Daniel M Lewin

Anne E Lewin, Legal Representative

Michael M Afergan

Andrew B Ellis

Sachin Katti

Zachary Kabelac

Rumen Hristov

A method for wireless detection of a subject rising from a rest state includes producing transmitted wireless signals from one or more transmitting antennas, receiving reflected wireless signals at one or more receiving antennas, and processing the reflected wireless signals in a computer. The computer iteratively aligns candidate trajectories with a template trajectory until the current and previous template trajectories are within a predetermined distance from each other. A final template trajectory is used to determine a lying-down surface exit initiation area, a lying-down surface exit initiation area exit time, a TUG plane or radius entry time, and a TUG time.

System and method for wireless detection and measurement of a subject rising from rest

The coexistence of a plurality of different wireless networks that concurrently operate in a common geographic region is optimized. A query is received from a wireless node requesting advice on specific portions of a radio frequency spectrum to use. A spectrum recommendation procedure is then run to generate advice on recommended portions of the radio frequency spectrum for the wireless node to use in order to minimize one or more of interference in the spectrum, or noise in the spectrum, or contention in the spectrum. A recommendation reply is then sent to the wireless node which includes information specifying the recommended portions of the radio frequency spectrum for the wireless node to use in order to minimize one or more of interference in the spectrum, or noise in the spectrum, or contention in the spectrum.

Cloud service for optimizing white-space networks coexistence

A distributed wireless communication system includes multiple access points, each with one or more antennas. The access points do not necessarily have synchronized transmitting and receiving radio frequency oscillators. Approaches to channel estimation between the access points and one or more wireless clients account for the lack of synchronization, and do not necessarily require capabilities at the clients that go beyond required or optional features of standard wireless Ethernet (e.g., 802.11n, 802.11g, or 802.11a), thereby supporting 'legacy' clients while supporting high data throughput approaches that provide coherent transmission from the multiple antenna of the access points.

Coherent transmission from distributed wireless transmitters using legacy receivers

In one aspect, a distributed coherent transmission system enables transmissions from separate wireless transmitters with independent frequency or clock references to emulate a system where all the transmitters share a common frequency or clock reference. Differences in frequency and/or phase between transmitters are addressed by suitably precoding signals before modulation at one or more of the transmitters based on a synchronizing transmission from one of the transmitters (e.g., a master transmitter) received at a corresponding receiver sharing the frequency or clock reference with each of the one or more transmitters. Such a distributed coherent transmission system can allow N single-antenna transmitters with independent frequency or clock references to emulate a single N-antenna Multi Input Multi Output (MIMO) transmitter, or implement schemes such as distributed superposition coding or lattice codes that require coherence across separate transmitters.

Coherent transmission from distributed wireless transmitters

An infrastructure 'insurance' mechanism enables a Web site to fail over to a content delivery network (CDN) upon a given occurrence at the site. Upon such occurrence, at least some portion of the site's content is served preferentially from the CDN so that end users that desire the content can still get it, even if the content is not then available from the origin site. In operation, content requests are serviced from the site in the usual manner, e.g., by resolving DNS queries to the site's IP address, until detection of the given occurrence. Thereafter, DNS queries are managed by a CDN dynamic DNS-based request routing mechanism so that such queries are resolved to optimal CDN edge servers. After the event that caused the occurrence has passed, control of the site's DNS may be returned from the CDN back to the origin server's DNS mechanism.

Origin server protection service apparatus

One embodiment is directed to transmitting encoded data over a broadcast medium to improve network throughput. A sending node may identify a first packet to be transmitted to a first network node and a second packet to be transmitted to a second network node. The sending node may determine whether the first network node stores the second packet and whether the second network node stores the first packet. If the sending node determines that the first network node stores the second packet and the second network node stores the first packet, it may code together the first and second packets to generate an encoded packet and may transmit the encoded packet over the broadcast medium. Thus, the first packet may be transmitted to the first network node and the second packet may be transmitted to the second node in a single transmission.

Methods and apparatus for network coding

Method and system for providing on-demand content delivery for an origin server

The invention is an intelligent traffic redirection system that does global load balancing. It can be used in any situation where an end-user requires access to a replicated resource. The method directs end-users to the appropriate replica so that the route to the replica is good from a network standpoint and the replica is not overloaded. The technique preferably uses a Domain Name Service (DNS) to provide IP addresses for the appropriate replica. The most common use is to direct traffic to a mirrored web site.

Global load balancing across mirrored data centers

The present invention addresses the known vulnerabilities of Web site infrastructure by making an origin server substantially inaccessible via Internet Protocol traffic. In particular, according to a preferred embodiment, the origin server is 'shielded' from the publicly-routable IP address space. Preferably, only given machines (acting as clients) can access the origin server, and then only under restricted, secure circumstances. In a preferred embodiment, these clients are the servers located in a 'parent' region of a content delivery network (CDN) tiered distribution hierarchy. The invention implements an origin server shield that protects a site against security breaches and the high cost of Web site downtime by ensuring that the only traffic sent to an enterprise's origin infrastructure preferably originates from CDN servers. The inventive &#x201c;shielding&#x201d; technique protects a site's Web servers (as well as backend infrastructure, such as application servers, databases, and mail servers) from unauthorized intrusion&#x2014;improving site uptime and in the process, customer loyalty.

Method and system for protecting web sites from public internet threats

Growing community of inventors

Cambridge, MA, United States of America

Hariharan Rahul