To: Sandeep taneja <sandeep.taneja@nsysinc.com> Cc: Monika <monika.Talwar@nsysinc.com>, owner-t10@t10.org, t10@t10.org Subject: Re: Hash address Generation From: George Penokie <gop@us.ibm.com> Date: Mon, 9 Oct 2006 13:19:02 -0500 X-Message-Number: 7306 Formatted message: HTML-formatted message Sandeep, We know that the hash addresses will duplicate. It is not possible for every 64 SAS address value to be uniquely identified in a 23 bit value. It's a question of probabilities. So given that the SAS addresses have to follow a certain structure to be valid there is a very low probability that two SAS addresses in the same system will hash to the same value and, even if that did happen, that a frame between those two would get misdirected. By the way your example cannot happen with a valid SAS address. Bye for now, George Penokie Dept 9A8 030-3 A410 E-Mail: gop@us.ibm.com Internal: 553-5208 External: 507-253-5208 Sandeep taneja <sandeep.taneja@nsysinc.com> Sent by: owner-t10@t10.org 10/09/2006 11:53 AM To t10@t10.org cc Monika <monika.Talwar@nsysinc.com> Subject Hash address Generation * From the T10 Reflector (t10@t10.org), posted by: * Sandeep taneja <sandeep.taneja@nsysinc.com> * Hi all I have a little doubt regarding the Hash Address generation Logic Ques: The following two 64 bit address maps to same 24 bit address 64 bit address value 23 bit hash adress 00000000_00000001h DB2777h FFFFFFFF_FFFFFFFFh DB2777h Then How Hash address is used to check that whether frame is routed properly or not , as from this we can assume that Hash Generation Logic is not One to One (64 bit address maps to unique 24 bit hash address value). Plz suggest......... regards Sandeep * * For T10 Reflector information, send a message with * 'info t10' (no quotes) in the message body to majordomo@t10.org