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CoffeeBlack

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Great Expectations

What would your expectations be for an internet provider for ping times between Eastern time zones and the West coast?  We're looking at some ip phone systems, and there is a limitation for 2 way traffic of around 150ms (~200ms) apparently?

We're looking specifically for:

Miami, FL to Seattle, WA
Cincinnati, OH to Seattle, WA
Indianapolis, IN to Los Angeles, CA
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Ben Hart
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Have you tried doing a SpeedTest between any of those locations?
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CoffeeBlack

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Yes I've done some from Indy and Cinn to Seattle.  Indy to Seattle is 70-110ms depending on location.  Our Ohio location is 80-120 ms.  Miami and LA haven't happened yet, but will in the near future.

I used the WonderNetwork to ping Miami and Seattle (79ms), and Chi and Seattle (54ms).  But I was hoping to see some other specific Internet connections.  I probably should have provided a pingable address in Seattle, and asked for some pings against that...  But as we already have services in place through TW, i'd like to see some other companies/peoples ping times.

Also I was kind of looking for a best practices...IE don't trust anything above 80ms for an ip phone, or make sure you have qos on, or cos etc.  I'd like to know what other people look for when they start looking at these kinds of things, or what people should have been looking now that they have their ip phone solution in place.
Actual distance has far less impact on the ping times than the number of hops involved.  The propogation delay related to the signal path length is roughly 2/3 the speed of light.  However, each router that passes the signal (and some switches that are not true "wire speed") will add to the delay.  Open traffic flow on the Internet can vary widely based on the moment to moment congestion.  In MPLS networks the delay will be less, but we typically see between 80 and 120 ms on most North America links that are not nearby.

QoS is always desired for Real Time traffic, regardless of distance.

In our experience, users with a really good ear can detect latency on IP phones when it exceeds 150 ms, although most people can not tell until it reaches about 200 ms.  The bigger problem is jitter (variance in latency) instead of the latency by itself.  We often have to adjust jitter buffers to maintain a smooth output, but that can add to the over latency as well (far more than the distance issue).  Also, things like echo cancellation are harder to maintain when there is big jitter swings.  

You will see an increase in latency / ping times when you use a carrier that hands off the signal to another carrier for part of the transmit path.  Most carriers have agreements with other carriers in place to extend their network footprint, but the impact on such hidden routing steps will vary.
Some of what we're looking at is, we have several locations in Seattle, and a central hub for our phone system in Indy.  This is an issue to some extent because as the center of the hub, people in Seattle may be making a hop in indy before coming back to a different building in Seattle.  What we need in Seattle really is a secondary hub, then a connection between that hub and the one in Indy.  That'll be a question for the question(s) for the folks providing the phone system though I suppose.

Thank you for your help, that gives me some info to look a little further in to.
What type of phone system are you using?  Most offer a remote controlled gateway approach that will allow the voice call packets to avoid the hairpinning transit via the hub.  Call control packets flow between the sites, but the actual calls are switched from end user device to the local device.

FYI, I am based in the Seattle area.
We have an iwatsu system.  Also that was all gibberish to me.  ;-)
Sorry, IP telephony speak.  :)
I can explain, but first, is the phone system you plan to use the Iwatsu IP or are you looking at installing a different telephony system?
Sorry I ended up out of town (not that internet wasn't available elsewhere), then didn't get back to this.  We're doing iwatsu and most of our phones are ip based.  We have a few analog lines in here as well.
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JRSCGI
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At this point I'll follow-up with the telecom guy.  I should have a few more questions I can ask him now thx!