Open Invention Network LLC

At&t Intellectual Property I, LP

Transtech Networks Usa, Inc.

At+t Corp.

Softshield, LLC

Leonard L Lu

Tsong-Ho Wu

Bo-Chao Cheng

Deh-Phone K Hsing

Zhuangbo Tang

Angela L Chiu

Seyhan Civanlar

David Hoeflin

The content-aware application switch and methods thereof intelligently switch client packets to one server among a group of servers in a server farm. The switch uses Layer 7 or application content parsed from a packet to help select the server and to schedule the transmitting of the packet to the server. This enables refined load-balancing and Quality of-Service control tailored to the application being switched. In an exemplary embodiment of the invention, a method includes maintaining a server load metric for each server in a group of servers; parsing application content from a packet; selecting a destination server from the group of servers, wherein selecting the destination server is dependent on the server load metric for each server, assigning a priority to the packet, the priority being dependent on the application content; and dropping the packet if the priority comprises at least one of a predetermined type.

Intelligent switching of client packets among a group of servers

This invention provides for a technique for selectively off-loading traffic from congested sub-regions of a network to more lightly-loaded regions by making use of Multiprotocol Label Switching (MPLS). For each network element, an Interior Gateway Protocol (IGP) routing is employed to provide re-routing and to identify congested links caused by re-routed trunks for each single failure. The re-routed traffic is then analyzed and alternate Label Switched Paths (LSPs) are identified for such traffic trunks so that the traffic is directed to the alternate LSPs during the single failure event.

Method and apparatus for communications traffic engineering

The content-aware application switch and methods thereof intelligently switch client packets to one server among a group of servers in a server farm. The switch uses Layeror application content parsed from a packet to help select the server and to schedule the transmitting of the packet to the server. This enables refined load-balancing and Quality of-Service control tailored to the application being switched. In another aspect of the invention, a slow-start server selection method assigned an initially boosted server load metric to a server newly added to the group of servers under load balancing. This alleviates the problem of the new server being swamped initially due to a very low load metric compared to that of others. In yet another aspect of the invention, a switching method dependent on Layercontent avoids delayed binding in a new TCP session. Layercontent is not available during the initial handshaking phase of a new TCP session. The method uses the Layercontent from a previous session as an estimate to help select the server and uses a default priority to scheduling the transmitting of the handshaking packets. Updated Layercontent available after the handshaking phase is then used to reset the priority for the transmit schedule and becomes available for use in load balancing of the next TCP session.

This invention provides a tool for reliability evaluation and performance analysis of an IP backbone network by using the network packet loss ratio as the main measurement. A queuing model and algorithm is presented for calculating packet loss at congested interfaces or links. A reliability model is presented for considering network hardware component failures such as router failures, ATM switch failures, and physical link failures. Based on the measurement and models presented, a network reliability and performance (NetRAP) apparatus calculates IP network reliability and performance measurements. The NetRAP apparatus uses the network topology, a traffic matrix, and the reliability parameters of a network as inputs and calculates the network packet loss ratio and sigma score, and provides a list of heavily congested links under non-failure or different single failure conditions.

IP backbone network reliability and performance analysis method and apparatus

A content-aware application switch and methods thereof intelligently switch client packets to one server among a group of servers in a server farm. The switch uses Layer 7 or application content parsed from a packet to help select the server and to schedule the transmitting of the packet to the server. This enables refined load-balancing and Quality-of-Service control tailored to the application being switched. In another aspect of the invention, a slow-start server selection method assigned an initially boosted server load metric to a server newly added to the group of servers under load balancing. This alleviates the problem of the new server being swamped initially due to a very low load metric compared to that of others. In yet another aspect of the invention, a switching method dependent on Layer 7 content avoids delayed binding in a new TCP session. Layer 7 content is not available during the initial handshaking phase of a new TCP session. The method uses the Layer 7 content from a previous session as an estimate to help select the server and uses a default priority to scheduling the transmitting of the handshaking packets. Updated Layer 7 content available after the handshaking phase is then used to reset the priority for the transmit schedule and becomes available for use in load balancing of the next TCP session.

Packet switch and method thereof dependent on application content

A content-aware application switch and methods thereof intelligently switch client packets to one server among a group of servers in a server farm. The switch uses Layeror application content parsed from a packet to help select the server and to schedule the transmitting of the packet to the server. This enables refined load-balancing and Quality-of-Service control tailored to the application being switched. In another aspect of the invention, a slow-start server selection method assigned an initially boosted server load metric to a server newly added to the group of servers under load balancing. This alleviates the problem of the new server being swamped initially due to a very low load metric compared to that of others. In yet another aspect of the invention, a switching method dependent on Layercontent avoids delayed binding in a new TCP session. Layercontent is not available during the initial handshaking phase of a new TCP session. The method uses the Layercontent from a previous session as an estimate to help select the server and uses a default priority to scheduling the transmitting of the handshaking packets. Updated Layercontent available after the handshaking phase is then used to reset the priority for the transmit schedule and becomes available for use in load balancing of the next TCP session.

Growing community of inventors

Holmdel, NJ, United States of America

Leonard L Lu