31 May
2011
31 May
'11
4:11 p.m.
On Fri, May 27, 2011 at 23:43, Jeff Brower <jbrower(a)signalogic.com> wrote:
Jan-
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
On Wed, May 25, 2011 at 06:54, Jeremya
<jeremy(a)electrosilk.net> wrote:
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). 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.