Multiplex communications – Data flow congestion prevention or control – Flow control of data transmission through a network
Reexamination Certificate
2006-06-13
2006-06-13
Nguyen, Steven (Department: 2668)
Multiplex communications
Data flow congestion prevention or control
Flow control of data transmission through a network
C370S412000
Reexamination Certificate
active
07061868
ABSTRACT:
The invention relates to a method for flow control in a switch and a switch controlled thereby. In order to ensure that no or few packets are dropped in a switch because of a congested internal memory, pause frames or stop command messages are sent to upstream senders. When to send pause frames are determined by monitoring the buffer contents of the switch and estimating the total expected contents of the links between the senders and the switch. The pause frames are sent to the most offending senders, i.e. the senders causing the largest queues in the switch. The switch comprises: a number of input ports, each receiving data cells on a respective link; a number of output ports sharing a buffer space in which each output port can reserve space for an output queue, wherein incoming data cells are switched to an appropriate output queue; a flow control means for pausing and un-pausing senders on selected links; and the method includes the steps of: monitoring the remaining available buffer space AS of the shared buffer; estimating the expected total content LE of the links; calculating a free margin (FM) as the remaining available buffer space minus the expected total content of the links FM=AS−LE. If the free margin sinks below a threshold AS−LE<A, then a selected link is paused; and if the free margin thereafter raises above a threshold AS−LE>B, then a selected paused link is un-paused.
REFERENCES:
patent: 5125096 (1992-06-01), Brantley, Jr. et al.
patent: 5189668 (1993-02-01), Takatori et al.
patent: 5493566 (1996-02-01), Ljungberg et al.
patent: 5524211 (1996-06-01), Woods et al.
patent: 5528591 (1996-06-01), Lauer
patent: 5584033 (1996-12-01), Barrett et al.
patent: 5742606 (1998-04-01), Iliadis et al.
patent: 5774453 (1998-06-01), Fukano et al.
patent: 5905870 (1999-05-01), Mangin et al.
patent: 5995486 (1999-11-01), Iliadis
patent: 6167054 (2000-12-01), Simmons et al.
patent: 6172963 (2001-01-01), Larsson et al.
patent: 6252849 (2001-06-01), Rom et al.
patent: 6456590 (2002-09-01), Ren et al.
patent: 6628613 (2003-09-01), Joung et al.
patent: 2001/0043566 (2001-11-01), Chow
patent: 2001/0050913 (2001-12-01), Chen et al.
patent: 2002/0118689 (2002-08-01), Luijten et al.
patent: 0 838 972 (1997-10-01), None
patent: 0 853 441 (1997-11-01), None
patent: 3283940 (1991-12-01), None
patent: 04197972 (1992-07-01), None
patent: 07270060 (1995-10-01), None
patent: 09212046 (1997-08-01), None
patent: 10107849 (1998-04-01), None
patent: 96/08899 (1996-03-01), None
patent: 99/00949 (1999-01-01), None
Kato, M., et al.:Performance Analysis of Reactive Congestion Control Based Upon Queue Length Threshold Values, IEE (1997) (abstract only).
Ahlfors Ulf
Fyhn Anders
Tufvesson Peter
Han Clemence
Nguyen Steven
Pillsbury Winthrop et al.
Switchcore AB
LandOfFree
Method for flow control in a switch and a switch controlled... 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 for flow control in a switch and a switch controlled..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for flow control in a switch and a switch controlled... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3624209