The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 26, 1988
Filed:
Dec. 31, 1986
Charles J Cotton, Hopatcong, NJ (US);
Stuart I Feldman, Harding Township, Morris County, NJ (US);
Walter D Sincoskie, Union Township, Union County, NJ (US);
Bell Communications Research, Inc., Livingston, NJ (US);
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 entries is not cleared.