Hi Gerard, ATM as a technology per se, is a high overhead technology. As the basic fact the fixed size cell is of 53 bytes and out of it the Cell Header consumes 5 bytes. So the net payload per cell is actually 48 bytes only, so effectively you are having a close to 10% overhead, and it is not the end, you have to leave some bandwidth on the error detection etc things also, because of which you are never able to use more than a tentative 90% bandwidth on any kind of technology.
So if you are getting a burst of 30 Mbps on a E3 link, (I would like to know about the bandwidth consumption tool or parameters used by you) you are not doing bad; for sure. HTH Vikram -----Original Message----- From: Dom [mailto:[EMAIL PROTECTED] Sent: Sunday, July 06, 2003 11:30 PM To: [EMAIL PROTECTED] Subject: RE: ATM Bandwith [7:71937] Somebody (I'm sorry I deleted the post), posted after me, and it does look like you are hitting the cell tax problem. With other (including layer 3 overheads) you are not doing to badly Sorry if this is not what you want to hear ;) Best regards, Dom Stocqueler SysDom Technologies Visit our website - www.sysdom.org -----Original Message----- From: Gerard Torin [mailto:[EMAIL PROTECTED] Sent: 06 July 2003 18:29 To: Dom; [EMAIL PROTECTED] Subject: RE: ATM Bandwith [7:71937] Hi Dom, we did test with TFY aplication, generating a burst traffic of 3000 bytes UDP. This aplication stressed the link, but I don`t undestard why not reach the maximun bandwith permited: 34Mbps. What do you think about this test? Is right? Dom wrote: -----Original Message----- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gerard Torin >Sent: 05 July 2003 19:06 >To: [EMAIL PROTECTED] >Subject: ATM Bandwith [7:71937] >Hi guys, >Anybody know how is built the ATM4S Bandwith?. For example, In ATM`s link of 34Mbps, Is true that 4Mbps is just only >header?, I ask that, because actually my company has it. But we don4t reach the maximun bandwith of 34Mbps. Yesterday, we >did stress test in the link and just only reach 30Mbps. >I thanks any comment. Please supply more details. How did you test and with what size packets? Cell tax (the overhead of breaking your data down in 53byte chunks) might account for hat you are observing. Best regards, Dom Stocqueler SysDom Technologies Visit our website - www.sysdom.org _____ Yahoo! Messenger Nueva versisn: Super Webcam, voz, caritas animadas, y mas !Gratis! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71969&t=71937 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
