Multicast routing algorithm
US4740954A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1986 |
| Grant date | Apr 26, 1988 |
| Priority date | — |
| Expiry date | Dec 31, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L45/16
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method for routing data packets correctly and efficiently among a plurality of hosts in a multicast is disclosed. The hosts are connected to a packet switching network comprising a plurality of packet switches interconnected by trunks. A memory associated with the route controller in each switch maintains a table whose entries are tuples of the form <address, trunk identification number, time>. In the case of multicast routing, the address is a multicast address. The trunk identification number is a number which uniquely identifies each of the trunks connected to the switch. Time is a timing parameter which is initially set to a certain predetermined value (designated Maxtime herein) and decremented periodically. When time reaches zero, the associated table entry is cleared. When a host wishes to join a multicast conversation (even if it is the first participant), it simply transmits a packet from itself to the multicast adddress. This packet will be broadcast over the entire spanning tree network. The host then continues to send packets to the multicast address, with a maximum interpacket time interval, smaller than Maxtime, to insure that at least one of the relevant table entr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.