On Fri, May 27, 2011 at 23:43, Jeff Brower jbrower@signalogic.com wrote:
Jan-
On Wed, May 25, 2011 at 06:54, Jeremya jeremy@electrosilk.net wrote:
These figures pale into insignificance compared to the power required for standard SIP devices - typically 5-8 watts per device multiplied by the number of devices.
When you factor in Gigabit Ethernet the power ups significantly.
Optimisation at the server level is not significant on any scale. Optimisation on communications power: i.e. end-devices, DSL & switches is where the power savings are important.
Sure, the total power consumption of the whole system is dominated by the power consumption of end-point devices, there's no doubt about that and the paper says that.
Nevertheless, as an ITSP you are typically paying for the energy consumed by your servers and in that case knowing what you can expect and how many servers you need is useful. Modern data-center servers have significant base-line power consumption and a portion of that needs to be attributed to the SIP service running on those servers.
Just want to clarify... I assume that no transcoding, transrating, or other "translation" between end points is included? I don't see any mention of rtpproxy or other media servers. I ask because these tend to be compute-intensive tasks that would have significant impact server energy usage and performance (e.g. max calls and calls-per-sec).
Correct, those tests did not include any manipulation of media streams. We were primarily interested in system components that are present in SIP based deployments and missing in Skype because we wanted to see how those two systems differ in terms of architecture, power consumption, etc.
We did run some tests with rtpproxy-like media relays though. You'll find some numbers in the paper.
-Jan