Cisco Technology, Inc.

Cisco Systems Inc.

Cayman Systems, Inc.

Arrowpoint Communications, Inc.

Kenneth P Siegel

John J Krawczyk

Steven Colby

Katherine Royce

Richard C Stevens

Raj Krishnan Nair

Scott G Wasson

J Bradford Parker

John Wroclawski

Scott Wasson

Rai Krishnan Nair

The invention is directed to techniques for managing communication between a client and multiple servers over a network through an intermediary network device (e.g., content switch). In response to a request for content from a client, the network device selects a server to respond to the request. The network device includes a flow manager that manages the flow of data from the server through the network device to the client. In response to a second request, the network device may select a different server to respond to the request. In this case, the flow manager manages the flow of data from the new server through the network device transparently for the client, so that the client communicates only through the network device regardless of which server is providing the response to the requests.

Methods and apparatus for directing a flow of data between a client and multiple servers

A content-aware flow switch intercepts a client content request in an IP network, and transparently directs the content request to a best-fit server. The best-fit server is chosen based on the type of content requested, the quality of service requirements implied by the content request, the degree of load on available servers, network congestion information, and the proximity of the client to available servers. The flow switch detects client-server flows based on the arrival of TCP SYNs and/or HTTP GETs from the client. The flow switch implicitly deduces the quality of service requirements of a flow based on the content of the flow. The flow switch also provides the functionality of multiple physical web servers on a single web server in a way that is transparent to the client, through the use of virtual web hosts and flow pipes.

Method and apparatus for directing a flow of packets based on request and server attributes

The invention is directed to techniques for allocating packets received by the flow control processor located on the input/output (I/O) communications interface of the data communications device to a forwarding entity or session processor, chosen from a plurality of session processors, for further processing or routing. The session processors have the same ability to make decisions relating to the processing and routing of the packet as does the flow control processor and can have per second packet processing rates that are different from the flow control processor located on the I/O communications interface of the data communications device. To allocate the packets to the session processors for further processing, the flow control processor processes information located within the header component of the received packet. Based upon the results of this processing, the flow control processor selects a session processor from a plurality of session processors and transfers the packet to the selected session processor for further processing and routing of the packet. The flow control processor on the I/O communications interface, therefore, acts to load balance incoming packets among other session processors, thereby alleviating potential congestion on the port caused by the reception of multiple packets from multiple clients and reducing potential degradation of performance of the data communications device. To allocate the packets to the session processors for further processing, the flow control processor processes information located within the header component of the received packet. Based upon the results of this processing, the flow control processor selects a session processor from a plurality of session processors and transfers the packet to the selected session processor for further processing and routing of the packet. The flow control processor on the I/O communications interface, therefore, acts to load balance incoming packets among other session processors, thereby alleviating potential congestion on the port caused by the reception of multiple packets from multiple clients and reducing potential degradation of performance of the data communications device.

Methods and apparatus for directing packets among a group of processors

Content-aware switching of network packets

Method and system for directing a flow between a client and a server

An method for interprocess communication and data exchange within a computer's software operating system executing on a computer network protocol translator having a central processing unit and associated memory, which includes encapsulating the message or data to be exchanged within certain header and footer information which defines the context of the transmission. Certain program routines are executed in conjunction with this context information which enable the software processes within the operating system to exchange data and to acknowledge the receipt of messages without having to generate and transmit return messages or pre-empt the operating system's execution sequence.

Network protocol translator including method and apparatus for reducing

Growing community of inventors

Nashua, NH, United States of America

Kenneth P Siegel