International Business Machines Corporation

Rama Mohan Yedavalli

Michael Steven Siegel

Clark Debs Jeffries

Jitesh Ramachandran Nair

Ravinder Kumar Sabhikhi

Gordon Taylor Davis

Colin Beaton Verrilli

Brian Mitchell Bass

James Johnson Allen, Jr

Claude Basso

Natarajan Vaidhyanathan

Ganesh Balakrishnan

Cedell Adam Alexander, Jr

Everett Arthur Corl, Jr

Raj Kumar Singh

Timothy James Smith

The decision within a packet processing device to transmit a newly arriving packet into a queue to await further processing or to discard the same packet is made by a flow control method and system. The flow control is updated with a constant period determined by storage and flow rate limits. The update includes comparing current queue occupancy to a threshold. The outcome of the update is adjustment up or down of the transmit probability value. The value is stored for the subsequent period of flow control and packets arriving during that period are subject to a transmit or discard decision that uses that value.

Retro flow control for arriving traffic in computer networks

A process control method and system including partitioning transmit decisions and certain measurements into one logical entity (Data Plane) and partitioning algorithm computation to update transmit probabilities into a second logical entity (Control Plane), the two entities periodically communicating fresh measurements from Data Plane to Control Plane and adjusted transmit probabilities from Control Plane to Data Plane. The transmit probability may be used in transmit/discard decisions of packets or instructions exercised at every arrival of a packet or instruction. In an alternative embodiment, the transmit probability may be used in transmit/delay decisions of awaiting instructions or packets exercised at every service event.

System and method for automatic management of many computer data processing system pipes

The decision within a packet processing device to transmit a newly arriving packet into a queue to await processing or to discard the same packet is made by a flow control method and system. The flow control is updated with a constant period determined by storage and flow rate limits. The update includes comparing current queue occupancy to thresholds and also comparing present queue occupancy to previous queue occupancy. The outcome of the update is a new transmit probability value. The value is stored for the subsequent period of flow control and packets arriving during that period are subject to a transmit or discard decision that uses that value.

Flow control in computer networks

In a network environment including one or more network processing (NP) devices implementing for communicating packets, each NP device supporting a forwarding table comprising entries to enable forwarding of received data packets from a source device to a destination device according to a routing protocol via a network connection, the network device routing receiving updated forwarding table entries from one or more network control devices executing routing protocol applications, a system and method for updating forwarding table entries comprises: generating for each forwarding table entry update, a data structure indicating identification of the routing protocol application and a version of a particular routing protocol application instance generating the entry update, the data structure received by the forwarding table and incorporated within a respective forwarding table entry; identifying for deletion forwarding table entries having data structures matching a designated selection criteria; and, deleting the designated forwarding table entries. By doing this old forwarding table entries in the forwarding table are updated efficiently without disrupting packet forwarding process.

Robust NP-based data forwarding techniques that tolerate failure of control-based applications

A primary ARP server and a backup ARP server are connected to an ATM communications network. The primary and backup ARP servers each have associated ATM addresses. Also, a LIS is connected to the ATM communications network. Either the primary or backup ARP server is the active ARP server and resolves IP addresses to ATM addresses for the LIS. When the backup ARP server recognizes the removal of a redundancy virtual channel connection (VCC) between the backup ARP server and the primary ARP server, the backup ARP server registers using the ATM address associated with the primary ARP server. This allows the backup ARP server to take over for the primary ARP server to become the active ARP server. In addition, a primary default gateway and a backup default gateway are connected to the ATM communications network. These default gateways have associated ATM addresses. One of the primary and backup default gateways is active at a time. The active default gateway provides routing services for hosts that do not run routing topology protocols. When the backup default gateway recognizes the removal of a redundancy virtual channel connection (VCC) between the backup default gateway and the primary default gateway, the backup default gateway registers a mapping between the ATM address associated with the backup default gateway and an IP address of the default gateway. In this manner the backup default gateway takes over for the primary default gateway to become the active default gateway.

Redundancy mechanisms for classical internet protocol over asynchronous

Growing community of inventors

Raleigh, NC, United States of America

Rama Mohan Yedavalli