Alcatel Lucent

Alcatel-lucent Canada Inc.

Wladyslaw Olesinski

Peter Mark Rabinovitch

Robert Elliott Robotham

Mustapha Aissaoui

Steve Driediger

Jordan (Jianping) Lu

Lie Qian

Yiyan Tang

Yuke Wang

Bashar Bou-Dlab

Apparatus and methods for real-time traffic classification based on off-line determined traffic classification rules are provided. Traces of real traffic are obtained and subjected to statistical analysis. The statistical analysis identifies the multidimensional domain space of characteristic traffic parameters. Classification rules associated with the identified domains are derived and provided to traffic classification points for real-time traffic classification. Traffic classification points, typically edge network nodes, sample packets in aggregate streams with a predetermined probability. Statistical information regarding the sampled flows is tracked in a table, the number of time a flow was sampled providing a probabilistic measure of the flow's duration before the flow terminates. The table entries, which predominantly track high bandwidth flows, are subjected to the classification rules for real-time classification of the sampled flows. Optionally, rules include an action to be taken in respect of flows having characteristics matching thereof. Advantages are derived from low overhead on-line real-time classification of high-bandwidth flows at low overheads before flow termination.

Statistical trace-based methods for real-time traffic classification

A Weighted Random Early Detection (WRED) algorithm is described. The WRED algorithm provides fairness to responsive TCP and non-responsive UDP traffic at a buffer of a communications system. Because TCP traffic is responsive to congestion occurrences while UDP traffic is not, without controls, UDP will monopolize the buffer bandwidth. This invention solves the problem by applying congestion control alogrithms to TCP and UDP traffic separately. Discard thresholds for UDP traffic are dynamically modified in a manner that limits UDP traffic to a provisioned percentage of the buffer's available bandwidth, while a traditional WRED algorithm is applied to TCP traffic.

Fair WRED for TCP UDP traffic mix

A method and apparatus for scheduling and servicing events using a calendar structure is described. In accordance with one preferred embodiment of the present invention, a calendar structure is provided to implement work-conserving methods (for example, queuing, such as fair queuing, or, as one specific example, weighted fair queuing (WFQ)). Such a calendar structure preferably provides two slots per tier and uses a temporal pointer based on virtual time. In accordance with another preferred embodiment of the present invention, a calendar structure is provided to implement shaping of flows of information. Such a calendar structure preferably provides one slot per tier and uses a temporal pointer based on real time. For scheduling, a preferred occurrence time at which an event is preferred to occur is calculated. Events having preferred occurrence times farther from a current time value denoted by the temporal pointer are scheduled on a calendar tiers of lower resolution, while events having preferred occurrence times nearer to the current time value denoted by the temporal pointer are scheduled on calendar tiers of higher resolution. For servicing, the events are selected from slots to which the temporal pointer is pointing. If a slot is being used to schedule an event pending servicing, the slot is considered to be an occupied slot. Occupied slots at higher resolution calendar tiers are serviced exhaustively over occupied slots at lower resolution calendar tiers.

Method and apparatus for scheduling and servicing events using a calendar structure

The sharing of forwarding states between multiple traffic paths is described. There is described a method for establishing a data traffic path in a communication network from a first node towards a second node. The method includes searching a set of pre-existing forwarding states for a pre-existing forwarding state associated with the first node for defining the traffic path from the first node towards the second node. If the pre-existing forwarding state for defining the traffic path cannot be found in the set of pre-existing forwarding states, then a new forwarding state for defining the traffic path from the first node towards the second node is generated the new forwarding state is used to establish the traffic path from the first node towards the second node. An apparatus implementing the method is described. The sharing of forwarding states as described may be used in MPLS enabled networks.

Forwarding state sharing between multiple traffic paths in a communication network

Growing community of inventors

Kanata, Canada

Wladyslaw Olesinski