Multicast methodology and apparatus for backpressure-based switching fabric
US6636510B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 27, 1999 |
| Grant date | Oct 21, 2003 |
| Priority date | — |
| Expiry date | May 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L47/129
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In an N×N packet switch, for example an ATM switch, multicast connections receive backpressure signals from congested output ports in the switch core. The cells in the connections are destination address modified not to send to the congested output port, but to continue sending to the other output ports in the connection. The multicast cells may include a user selected primary route identification and be queued in a unicast input queue for the primary route before being destination address modified. Destination address modification for congestion may be accompanied by partial packet discard, through destination address modification of the remaining cells forming part of a multiple cell packet to remove the destination address for the congested port (whether or not it is now congested) where one of the multiple destination addresses of one of the cells in the packet has been modified to remove the destination address of the congested output port. Destination address modification for congestion, without or without partial packet discard, may be accompanied by hybrid head of line blocking performed by not sending from a multicast queue if an output port on one of the multicast l…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.