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:
Nov. 24, 1998
Filed:
Nov. 21, 1997
Shmuel Shaffer, Palo Alto, CA (US);
William Joseph Beyda, Cupertino, CA (US);
Siemens Business Communication Systems, Inc., Santa Clara, CA (US);
Abstract
A system for controlling traffic on a contention-based local area network (LAN) such as one according to the CSMA/CD or Ethernet specification. To selectively preempt low priority messages on the LAN so that high priority messages may be transmitted, the system uses a station profile table (260) that holds information relating to an average frame length for messages transmitted from each station on the LAN. When a station connected to the LAN through a network interface (250) needs to transmit a high priority message such as a voice communication, a traffic monitor (240) checks for a low priority message on the LAN. If a low priority message is detected, a station identifier, priority level, and length of frame already transmitted are determined, and an average frame length is read from the station profile table (260). If the length of frame already transmitted is less than a predetermined threshold, then a computing element (220) transmits the high priority message through the network interface (250) to the LAN, to force a collision. After waiting for a period shorter than the standard backoff period defined by the CSMA/CD specification, the high priority message is retransmitted.