Multiplex communications – Pathfinding or routing – Switching a message which includes an address header
Reexamination Certificate
1999-05-19
2004-03-16
Pham, Chi (Department: 2667)
Multiplex communications
Pathfinding or routing
Switching a message which includes an address header
C370S395400, C370S429000
Reexamination Certificate
active
06707824
ABSTRACT:
FIELD OF THE INVENTION
This invention relates generally to computer networks, and more particularly, to a method and apparatus for flexible egress traffic queuing.
BACKGROUND OF THE INVENTION
In the field of data routing in computer networks, an Internet service provider (ISP) user typically has much more stringent requirements than an enterprise user because the routers will be subjected to the adverse Internet routing environment in the world. There are three typical architectural requirements that such routers must support, described below.
A. Stable Operation
Although it sounds trivial, the notion of stable operation has been elusive in the ISP community, as witnessed by various Internet “brown-outs” since it's inception. One paper on Internet scaling “Scaling the Internet during the T3 NSFNET Years”, C. Villamizar, Oct. 22, 1997, articulates the basic requirements which ISPs demand from their networking equipment in order to provide a stable network. In addition to forwarding performance and scaling requirements, ISPs typically expect several operational attributes, given below.
1. Stability under adverse conditions. The router must remain stable and deterministic under arbitrarily high traffic loads or a flood of routing update changes.
2. Low packet loss to stable destinations. The effects of unstable routes (flapping) should not impact a router's ability to forward traffic to stable routes.
3. Reasonable fairness and congestion control. Sufficient buffering capacity, avoidance of head-of-line blocking, advanced queueing algorithms, and sophisticated discard techniques must be provided.
B. Service Differentiation
Recently it has become clear that service providers cannot make adequate margins by offering flat-rate access and undifferentiated service. The ability to offer tiered services, and to guarantee service levels, is crucial to the economic and competitive health of ISPs. The airline industry's first-class, business-class and coach-class offerings provide a meaningful analogy for Internet service differentiation: a small number of customers are willing to pay for premium service, if it can be guaranteed. The concentrator's must enable ISPs to offer differentiated services based on multiple queues and advanced, intelligent Traffic Management features.
C. Superior Reliability
ISP routers must provide a greater level of reliability and availability than known router architectures. Part of this flows from designing with stability in mind, but providing additional fault tolerance features adds another dimension of resiliency. ISP routers should be designed without any single points of failure, and all software designs should incorporate fault isolation principles.
Therefore, there is a need for a way to route data in computer networks that provides stable operation, service differentiation, and superior reliability. Such an invention should be stable under adverse conditions, insure low packet loss to stable destinations, and provide reasonable fairness and congestion control.
SUMMARY OF THE INVENTION
The present invention provides a method, apparatus and article of manufacture for enabling flexible egress traffic queuing. A queue selection word is generated and a data queue is monitored for data. An output mask word is generated associating the data queue to an output channel and a priority value if the data queue contains data. The output channel is processed according to the queue selection word and the output mask word.
REFERENCES:
patent: 5056011 (1991-10-01), Yoshitake et al.
patent: 5742587 (1998-04-01), Zornig et al.
patent: 6044061 (2000-03-01), Aybay et al.
patent: 6092116 (2000-07-01), Earnest et al.
patent: 6141323 (2000-10-01), Rusu et al.
patent: 6160812 (2000-12-01), Bauman et al.
patent: 6201792 (2001-03-01), Lahat
patent: 6222822 (2001-04-01), Gerardin et al.
patent: 6377583 (2002-04-01), Lyles et al.
patent: 6424621 (2002-07-01), Ramaswamy et al.
patent: 6510164 (2003-01-01), Ramaswamy et al.
Achilles Heather
Gallo Paul
Podlipec Mark
Pothier Peter
Blakely , Sokoloff, Taylor & Zafman LLP
Hoang Thai D
Nortel Networks Limited
Pham Chi
LandOfFree
Method and apparatus for flexible egress traffic queuing does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for flexible egress traffic queuing, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for flexible egress traffic queuing will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3250297