Dear Nanog members, I am a PhD student at University of Toronto and I am working on traffic burstiness in data centers. In the following I am asking two questions to raise motivation for my research. I appreciate if anyone could answer these questions to their best knowledge. *The questions are:* 1) ‘Bursty’ is a word with no agreed meaning. How do you define a bursty traffic? 2) If you are involved with a data center, is your data center traffic bursty? -- If yes, -- Do you think that it will be useful to supress the burstiness in your traffic? (For example by pacing the traffic into shorter bursts) -- If no: -- Are you already supressing the burstiness? How? -- Would you anticipate the traffic becoming burstier in the future? Thanks, Monia ------------------ Monia Ghobadi PhD Student University of Toronto http://www.cs.utoronto.ca/~monia/
Hi Monia, 'Burst' is a very broad term. It would be useful to clarify to what you are referring.. I can think of a few possibilities: - Data Transmission: The length of an uninterrupted flow of information. - Traffic Engineering: The ability for traffic to temporarily exceed it's allocated (average) bandwidth share. - Internal Event: A backup (scheduled) or a server failure (adhoc) altering traffic patterns. - External Event: Marketing campaign / event coinciding with increased traffic towards say, a website. Perhaps -> Over what period of time is a 'Burst'..? Cheers, Heath On Sun, Sep 9, 2012 at 10:23 AM, Monia Ghobadi <monia@cs.toronto.edu> wrote:
Dear Nanog members,
I am a PhD student at University of Toronto and I am working on traffic burstiness in data centers. In the following I am asking two questions to raise motivation for my research. I appreciate if anyone could answer these questions to their best knowledge. *The questions are:*
1) ‘Bursty’ is a word with no agreed meaning. How do you define a bursty traffic? 2) If you are involved with a data center, is your data center traffic bursty? -- If yes, -- Do you think that it will be useful to supress the burstiness in your traffic? (For example by pacing the traffic into shorter bursts) -- If no: -- Are you already supressing the burstiness? How? -- Would you anticipate the traffic becoming burstier in the future?
Thanks, Monia
------------------ Monia Ghobadi PhD Student University of Toronto http://www.cs.utoronto.ca/~monia/
Bursty is a very relative thing. It depends on the time frame you are considering. For example, at any given instant of time a circuit is either carrying data or it isn't. The network is always either 100% in use or 100% idle if you look at it in an instantaneous fashion. There is also a misconception that bursty is bad. In very fast networks, the systems complete their transmissions very quickly so appear bursty. In a lower bandwidth network the system may transmit almost continuously because there is always data queued for transmission. This would appear as non-bursty continuous traffic. What you are really looking at here is the value and effect of traffic shaping. You should probably repose your question and ask about traffic shaping. In my opinion, like most QoS mechanisms, traffic shaping is something you do as a compromise to get the best service in a network that does not have enough bandwidth or has high latency. The best solution is almost always more bandwidth. The idea of suppressing bursts is not something that I think would be optimal. What you are saying is really that a system has data to send but I am not going to allow it to go out as fast as possible. I am going to do some kind of traffic shaping which might be more fair to other traffic but at the end of the day, all you can do is add delay. Steven Naslund -----Original Message----- From: Monia Ghobadi [mailto:monia@cs.toronto.edu] Sent: Saturday, September 08, 2012 7:24 PM To: NANOG@nanog.org Subject: Traffic Burstiness Survey Dear Nanog members, I am a PhD student at University of Toronto and I am working on traffic burstiness in data centers. In the following I am asking two questions to raise motivation for my research. I appreciate if anyone could answer these questions to their best knowledge. *The questions are:* 1) 'Bursty' is a word with no agreed meaning. How do you define a bursty traffic? 2) If you are involved with a data center, is your data center traffic bursty? -- If yes, -- Do you think that it will be useful to supress the burstiness in your traffic? (For example by pacing the traffic into shorter bursts) -- If no: -- Are you already supressing the burstiness? How? -- Would you anticipate the traffic becoming burstier in the future? Thanks, Monia ------------------ Monia Ghobadi PhD Student University of Toronto http://www.cs.utoronto.ca/~monia/
participants (3)
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Heath Jones -
Monia Ghobadi -
Naslund, Steve