Fujitsu Corporation

Lucent Technologies Inc.

Yiwei Thomas Hou

Zhi-Li Zhang

Tomohiko Taniguchi

Shivendra S Panwar

Hong-Yi Tzeng

Zhenhai Duan

Yingfei Dong

A method and apparatus for packet scheduling using a virtual time stamp for a high capacity combined input and output queued switching system. A network employs a virtual time reference system (VTRS) to generate packet virtual time stamps associated with each packet traversing the network. The VTRS includes edge conditioners located at the edge of the network that receive unregulated packet traffic and generate regulated packet traffic for a given flow. The edge conditioners also add a packet virtual time stamp to each incoming packet. Core routers within a network core reference the packet virtual time stamps to schedule packet flow. The core routers also update the packet virtual time stamps using virtual delays. The packet virtual time stamps are removed from the packets when the packets leave the network core through an edge conditioner.

Method and apparatus for packet scheduling using virtual time stamp for high capacity combined input and output queued switching system

A method and apparatus for allocating bandwidth within a network domain. A centralized bandwidth broker maintains a link-level database including detailed flow data for individual links in a network domain and a path-level database including summarized flow data for individual paths in the network domain. The bandwidth broker determines bandwidth allocations at a path-level by allocating discrete amounts of bandwidth, termed quotas, based on flow requests. If a flow request cannot be satisfied by allocating quotas, then the bandwidth broker uses the link-level database to recover bandwidth from unused bandwidth by other paths on the same link in order to satisfy the flow request. In another embodiment of a bandwidth broker, the centralized bandwidth broker is replaced by a distributed bandwidth broker including a central bandwidth broker and one or more edge bandwidth brokers. An edge bandwidth broker conducts path-level allocations and requests or releases quotas from and to the central bandwidth broker. The central bandwidth broker conducts link-level allocations and allocates or de-allocates quotas to and from the path maintained by the edge bandwidth broker.

Method and apparatus for a bandwidth broker in a packet network

A method and system of generating performance metrics for network traffic being transferred in and out of an intranet. Network traffic is non-intrusively measured from a server to client perspective within periodic measurement time intervals. The network traffic is analyzed based on each connection made from a server to a client and the measurement time interval. Using the network traffic analyzed, performance metrics are generated. Accumulated performance metrics are also generated when a connection extends beyond a measurement time interval.

Server-based network performance metrics generation system and method

A packet network employs flow control providing assigned rates to sessions in accordance with a general max-min (GMM) rate allocation. The GMM rate allocation accounts for the minimum cell rate and peak cell rate requirements for each session. For one case, a centralized flow control algorithm is employed that sorts sessions based on increasing minimum cell rate. The centralized flow control algorithm employs an iterative process of increasing the rate of the smallest rate session and adding sessions to the process when the smallest rate session equals the next higher rate session. The rates are increased until the rate either reaches the peak cell rate of the session or the link saturates. For a second case, a distributed flow control algorithm is employed with a distributed protocol within the network to allocate capacity of network links to sessions. For the distributed flow control algorithm, an iterative process of rate allocation uses a modified version of the Consistent Marking method. In the modified version of the Consistent Marking method, a saturated link only marks those sessions reaching a corresponding GMM-bottleneck link rate on links elsewhere in the network. The session traversing its own GMM-bottleneck link is not marked.

Growing community of inventors

Santa Clara, CA, United States of America

Yiwei Thomas Hou