The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 08, 2002
Filed:
Dec. 31, 1997
Arthur Lin, San Ramon, CA (US);
Thomas J. Edsall, Mountain View, CA (US);
Tauseef Hashmi, Freemont, CA (US);
Cisco Technologies, Inc., San Jose, CA (US);
Abstract
A router includes a classifier that classifies packets assigned to 2 classes of service into 2 classes of service that are supported by the router. The classifier then sets the loss priorities of the respective packets to one of m levels. The router uses a modified weighted random early detection scheme that is based on probabilities of discard associated with the 2 classes of service to determine whether to retain or discard particular packets. The router uses a single buffer to store packets directed to all of the various output ports. The available storage locations in the buffer are linked to a free queue and a weighted average depth of the free queue, is used to determined whether or not to retain a given packet. The router compares the weighted average depth of the free queue to maximum and minimum thresholds associated with the particular 2 class of service to which the packet is assigned. If the weighted average is above the maximum threshold, the packet is retained. If the weighted average is below the minimum threshold, the packet is discarded. If the weighted average is between the two thresholds, a probability of discard that is based on the 2 classes of service is calculated and compared to a random value to determine whether or not the packet should be retained. If the probability of discard exceeds the random value, the packet is discarded. The other packets exit various output ports of the router based on weighting factors associated with the 2 classes of service.