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:
May. 05, 2015
Filed:
Feb. 25, 2013
Lsi Corporation, San Jose, CA (US);
LSI Corporation, San Jose, CA (US);
Abstract
A method of priority based connection arbitration in a SAS topology is disclosed introducing a PRIORITY field to an SAS open Address Frame (OAF). As the expander arbitrates the multiple OAFs in competition for an Expander Link, it compares the PRIORITY fields of the arbitrating OAFs. The OAF with highest value of PRIORITY is awarded the destination connection path. In case of equal PRIORITY, the next arbitration is based on the value of Arbitration Wait Time (AWT). This priority based arbitration ensures high availability of SAS connection links to the SAS targets with high priority OAFs which in turn will lead to better quality of service for those SAS targets. PRIORITY field in the OAF is set by the SAS targets based on the current OAF priority and also set by directly attached SAS storage expanders through a modification of the OAF during transit through the expander.