Amit K Gupta

US Patent:

6389532, May 14, 2002

Filed:

Apr 20, 1998

Appl. No.:

09/063630

Inventors:

Amit Gupta - Palo Alto CA
Radia J. Perlman - Acton MA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

G06F 124

US Classification:

713 60, 713 53, 713 76

Abstract:

A method and apparatus for filtering packets uses digital signatures to filter packets in a network. A filter point, such as a router or firewall to an intranet, receives a packet including a header, detects the existence of a signature in the header, tests the validity of the signature using a public key, and forwards the packet in accordance with the validity of the signature. A sender uses a private key obtained from an owner to generate the signature, which is created by encrypting a fingerprint which corresponds to the data in the packet. Public keys are created by an owner which installs them in a domain name system or a certification server. Private keys are also created by the owner but are disseminated only to authorized senders. A method and apparatus for sending packets stores a private key in a memory of the data processor, generates a signature using the private key, installs the signature into a header of a packet; and sends the packet.

US Patent:

6487538, Nov 26, 2002

Filed:

Nov 16, 1998

Appl. No.:

09/192874

Inventors:

Amit Gupta - Fremont CA
Sriraman Venkataraman - London, GB
Geoffrey Baehr - Menlo Park CA

Assignee:

Sun Microsystems, Inc. - Santa Clara CA

International Classification:

G06F 1760

US Classification:

705 14, 709219

Abstract:

A method and apparatus for local advertising. Internet Service Providers (ISPs) or proxies owned by an ISP insert advertisements transmitted from a web host to a client. The advertisement may be stored in the proxys cache or may be retrieved from a web server for an advertiser. By providing the ISP with the ability to insert the advertisement, advertisements appear on small web sites that do not normally attract advertisers. Additionally, due to the number of advertisements placed by an ISP, small advertisers may have their advertisement appear in connection with frequently used web sites. One or more embodiments of the invention provide for an ISP to collect and store demographic information such as the users age, residence, credit history, etc. Additionally, stored information may include web sites the user has accessed, time spent on each web site, and any searches performed by the user. The profile information may be utilized by the proxy to conduct targeted advertising and to associate a cost with certain demographic information.

US Patent:

6567857, May 20, 2003

Filed:

Jul 29, 1999

Appl. No.:

09/363472

Inventors:

Amit Gupta - Fremont CA
Geoffrey Baehr - Menlo Park CA

Assignee:

Sun Microsystems, Inc. - Santa Clara CA

International Classification:

G06F 1300

US Classification:

709238, 709242, 370235

Abstract:

In embodiments of the invention, a method and apparatus for dynamic proxy insertion in network traffic path is described. According to one or more embodiments of the invention, a request and/or response message may be modified to include one or more thru-proxy tags to identify a network (or traffic) node (e. g. , a proxy, server, or intermediary). For example, a request directed to a server or a response directed to a client may be altered to insert a plurality of intermediate or final destination designations. In so doing, a path of a request or response may be altered dynamically. A thru-proxy tag in a response may be inserted in a related request to identify a destination or node such that the request is sent to the destination in the thru-proxy tag before being sent to an origin server. Thru-proxy tags may be used to identify multiple and/or alternate destinations.

US Patent:

6519646, Feb 11, 2003

Filed:

Sep 1, 1998

Appl. No.:

09/146381

Inventors:

Amit Gupta - Fremont CA
Elliot Poger - San Francisco CA
Christoph Schuba - Mountain View CA

Assignee:

Sun Microsystems, Inc. - Santa Clara CA

International Classification:

G06F 1516

US Classification:

709229, 709245

Abstract:

A method and apparatus for encoding characteristics for the retrieval of information. Depending on the characteristics, some methods for retrieving information may be preferred. If information is too large to utilize UDP, then TCP may be preferred. In addition, if information is not cacheable, then it is preferable to retrieve the information directly from the server instead of searching the cache first. A URL (Uniform Resource Locator) is utilized on the internet to specify the application protocol (e. g. , http), the domain name (e. g. , www. sun. com), and file location (e. g. , /users/hcn/index. html). The suffix of a file indicator is utilized to identify how to process the data or information subsequent to retrieval. One or more embodiments of the invention provide for encoding characteristics of data to be transferred that indicates or hints at an optimal method to retrieve the data. For example, the URL may specify that TCP is the preferred transfer protocol, thereby avoiding an attempted transfer using UDP.

US Patent:

6553461, Apr 22, 2003

Filed:

Dec 10, 1999

Appl. No.:

09/459320

Inventors:

Amit Gupta - Fremont CA
Geoffrey Baehr - Menlo Park CA

Assignee:

Sun Microsystems, Inc. - Santa Clara CA

International Classification:

G06F 1200

US Classification:

711137, 711118, 711213

Abstract:

A client is given control over the pre-fetching of resources. The client may be, for example, resident on an electronic device such as a computer system that caches resources. The resources may be, for instance, web pages. Identifying property values that are intrinsically tied to the contents of the resources are used to determine whether resources are already resident within the cache prior to pre-fetching the resources. In addition, the client may request information regarding a resource to assist the client in determining whether to pre-fetch the resource. Such information may include the size of the resource and other information.

US Patent:

6577599, Jun 10, 2003

Filed:

Jun 30, 1999

Appl. No.:

09/344264

Inventors:

Amit Gupta - Fremont CA
Michael Speer - Mountain View CA

Assignee:

Sun Microsystems, Inc. - Santa Clara CA

International Classification:

H04J 314

US Classification:

370236, 370238

Abstract:

A method and apparatus for efficient and reliable multicasting in a network environment. In embodiments of the invention, a sender transmits identical information encapsulated in data packets to a plurality of receivers. Periodically, receivers submit responses that include control information regarding the loss or receipt of data packets transmitted by the sender. Using these information a sender retransmits any undelivered packets to intended receivers. Responses submitted by the participating receivers, generate a traffic flow that can consume a substantial portion of the network bandwidth. Thus, in embodiments of the invention, the rate at which the responses are submitted is monitored and controlled to minimize control traffic. Over congestion of the network bandwidth with control information is undesirable as it adversely effects the data transmission rate. Thus, in embodiments of the invention, packet loss responses are generated at time intervals.

US Patent:

6584075, Jun 24, 2003

Filed:

Jun 30, 1997

Appl. No.:

08/886130

Inventors:

Amit Gupta - Mountain View CA
Raphael Rom - Palo Alto CA
Tony Hsiao - Fremont CA

Assignee:

Sun Microsystems, Inc. - Santa Clara CA

International Classification:

H04L 1228

US Classification:

370256, 370351, 370408

Abstract:

A routing engine for a node controller of a switch or for a router provides enhanced routing for unicast and multicast connections by representing preferred routing trees, associated with different bandwidths and quality of service indications, as tables having, for each entry, a node identification, a parent node identification, a link identifier and ah effective distance by which a node identified by the node identification is separated from the controller or router. The routing engine adapts quickly to changes in network configurations, such as link failure, by quickly patching a table affected by the failure in order to maintain service until a new preferred routing tree can be calculated. Recalculations of preferred routing trees are avoided by using said table to determine whether a new link or a restored link could possibly provide a more cost effective route than that specified in the existing table.

US Patent:

6590895, Jul 8, 2003

Filed:

Oct 15, 1998

Appl. No.:

09/173228

Inventors:

Amit Gupta - Fremont CA
Radia J. Perlman - Acton MA

Assignee:

Sun Microsystems, Inc. - Palo Alto CA

International Classification:

H04L 1256

US Classification:

370394, 714748

Abstract:

Protocols that provide more efficient operation in dynamic and heterogeneous networking environments are defined. The protocols present a range of levels of error control and sequence order control. Traffic in a link between neighboring network devices is segregated into flows. Each flow is managed in accordance with a selected protocol. It is possible to simultaneously employ different protocols for respective flows within the link.