Method and apparatus for controlling congestion in a network node
US5867480A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 1996 |
| Grant date | Feb 2, 1999 |
| Priority date | — |
| Expiry date | Sep 12, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2012/5679
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In a network node having a host system coupled to a network by an adapter, VC-specific congestion is detected and reported to the host system. The host memory includes rx slots or buffers, each corresponding to one of one or more supported slot types. Per-VC slots consumed counters are maintained to count slot consumption for each active VC. Free buffer FIFOs are maintained for each of the one or more slot types, which have a predetermined congestion threshold associated therewith. Entries in each free buffer FIFO correspond to an rx slot posted by the host system. When a new rx slot or buffer in host memory is to be allocated to an incoming cell received on a given VC, the slots consumed counter is compared to the predetermined congestion threshold. If they are equal, the VC is at threshold level and the incoming cell is discarded and a report is sent to the host system. If the slots consumed counter is below threshold, a new rx slot is allocated for the reception of the data and the slots consumed counter is incremented. If the VC is credit-based flow control enabled and the slots consumed counter is below threshold, a credit is returned. If the VC is credit-based flow control en…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.