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The delay is excessive

Posted: Wed May 12, 2010 9:07 am
by olgatree
I have a Telo connected behind a D-link DIR-655 router and a Motorola 6120 docsys 3.0 modem (both in the basement). In general, I very happy with the quality of the voice signal and haven't had any issues. The delay is a problem and haven't been able to find any info on resolving it. Below is info about my connection. I notice my TCP delay is high. Can anyone offer some advice?

VoIP test statistics
--------------------
Jitter: you --> server: 0.1 ms
Jitter: server --> you: 3.5 ms
Packet loss: you --> server: 0.0 %
Packet loss: server --> you: 0.0 %
Packet discards: 0.0 %
Packets out of order: 0.0 %
Estimated MOS score: 4.0
Speed test statistics
---------------------
Download speed: 2082368 bps
Upload speed: 2263160 bps
Download quality of service: 88 %
Upload quality of service: 98 %
Download test type: socket
Upload test type: socket
Maximum TCP delay: 182 ms
Average download pause: 14 ms
Minimum round trip time to server: 36 ms
Average round trip time to server: 68 ms
Estimated download bandwidth: 51200000bps
Route concurrency: 24.587393
Download TCP forced idle: 85 %
Maximum route speed: 14563328bps

Re: The delay is excessive

Posted: Wed May 12, 2010 10:50 am
by sfhub
Try connecting your PC directly to the cable modem and rerunning the VOIP test (you need to reboot the cable modem after connecting the PC or it will still be configured to use the MAC address of the router)

If the latency is still variable, then the problem is on the ISP side. You need to complain to them.

Re: The delay is excessive

Posted: Wed May 12, 2010 11:14 am
by olgatree
Will do. I'll report back with the findings.

Re: The delay is excessive

Posted: Thu May 13, 2010 5:06 am
by Tiger5353
You might check this post out to see if it will help you with your router settings

http://www.oomacare.com/forums/viewtopi ... 7bf105e33f
olgatree wrote:I have a Telo connected behind a D-link DIR-655 router and a Motorola 6120 docsys 3.0 modem (both in the basement). In general, I very happy with the quality of the voice signal and haven't had any issues. The delay is a problem and haven't been able to find any info on resolving it. Below is info about my connection. I notice my TCP delay is high. Can anyone offer some advice?

VoIP test statistics
--------------------
Jitter: you --> server: 0.1 ms
Jitter: server --> you: 3.5 ms
Packet loss: you --> server: 0.0 %
Packet loss: server --> you: 0.0 %
Packet discards: 0.0 %
Packets out of order: 0.0 %
Estimated MOS score: 4.0
Speed test statistics
---------------------
Download speed: 2082368 bps
Upload speed: 2263160 bps
Download quality of service: 88 %
Upload quality of service: 98 %
Download test type: socket
Upload test type: socket
Maximum TCP delay: 182 ms
Average download pause: 14 ms
Minimum round trip time to server: 36 ms
Average round trip time to server: 68 ms
Estimated download bandwidth: 51200000bps
Route concurrency: 24.587393
Download TCP forced idle: 85 %
Maximum route speed: 14563328bps

Re: The delay is excessive

Posted: Thu May 13, 2010 5:50 am
by olgatree
Thanks, The link is to the guide that I actually followed to setup my system.

I ran another test after plugging directly into the modem and the result is below.

The TCP delay is actually worse.

VoIP test statistics
--------------------
Jitter: you --> server: 0.4 ms
Jitter: server --> you: 3.9 ms
Packet loss: you --> server: 0.0 %
Packet loss: server --> you: 0.0 %
Packet discards: 0.0 %
Packets out of order: 0.0 %
Estimated MOS score: 4.0

Speed test statistics
---------------------
Download speed: 2117216 bps
Upload speed: 2250688 bps
Download quality of service: 93 %
Upload quality of service: 98 %
Download test type: socket
Upload test type: socket
Maximum TCP delay: 208 ms
Average download pause: 14 ms
Minimum round trip time to server: 8 ms
Average round trip time to server: 71 ms
Estimated download bandwidth: 42400000bps
Route concurrency: 20.026299
Download TCP forced idle: 83 %
Maximum route speed: 65535000bps

Re: The delay is excessive

Posted: Thu May 13, 2010 8:10 am
by sfhub
So the problem you are seeing with inconsistent latency is on the ISP side or somewhere along the route.

Try using something like pingplotter.com to see where the delays are happening.

Then you need to let your ISP know.

Re: The delay is excessive

Posted: Thu May 13, 2010 10:23 am
by olgatree
I will and thanks. Ultimately, what could my ISP(Comcast) do to resolve it?

Re: The delay is excessive

Posted: Thu May 13, 2010 10:49 am
by sfhub
Depends, if it is one of their routers, they can figure out why. If it is one of their provider's routers, they can move along the chain. If it is the server's routers or server's providers routers, then they need to address it. This all assumes you could get in touch with someone with authority and who cares, at the ISP. It is quite possible you run into a brick wall of first-line support that you are unable to breach.

It's also possible they may claim the latency is normal. Your stats are otherwise not bad, no dropped packets, good throughput, etc. There are online gamers that complain that latency with cable modem setups is not a strong point. For consistent latency they go to DSL which gets you a more direct line to the ISP before the sharing starts.

I think that is looking too far forward though. First run pingplotter and verify that the latency variability you see with the voiptest is confirmed by ping tests over time and if so where along the path the high ping times start.

Re: The delay is excessive

Posted: Thu Jun 24, 2010 1:50 pm
by Jethro_g
I am experiencing this same issue and wondering if anyone has come up with a solid resolution. The sound quality of OOMA is excellent. Sound is as good as my land line if not better, occasionally there is a glitch or blip in that you or the person you are talking to will hear a noise or miss a part of the conversation. But overall, no real complaints with sound quality.
The issue I have is that there seems to be a 1-2 second delay in the conversation seems to be on both ends (although, I have not done and “real” comparison). Unfortunately, if I can not get it either eliminated or reduced, I am going to have to go back to my land line. I would LOVE to blow them off and completely go with OOMA, however, the delay is just unacceptable.
I am an IT professional and have tried the suggestions that I read about in the blogs here and have some idea as to what I am looking for when it comes to most of the standard tests (speedtest.net, pingtest.net). And would be happy to provide any results that would be helpful in troubleshooting.

The Telo sits outside my router (Modem>OOMA Telo>Router). Upload QoS is set to 384, Download is 0.

I have posted the basics from my tests here:

VoIP test statistics
--------------------
Jitter: you --> server: 6.8 ms
Jitter: server --> you: 16.4 ms
Packet loss: you --> server: 0.0 %
Packet loss: server --> you: 0.2 %
Packet discards: 0.0 %
Packets out of order: 0.0 %
Estimated MOS score: 3.7

Speed test statistics
---------------------
Download speed: 1173856 bps
Upload speed: 434832 bps
Download quality of service: 41 %
Upload quality of service: 86 %
Download test type: socket
Upload test type: socket
Maximum TCP delay: 635 ms
Average download pause: 42 ms
Minimum round trip time to server: 133 ms
Average round trip time to server: 146 ms
Estimated download bandwidth: 1600000bps
Route concurrency: 2.1599147
Download TCP forced idle: 0 %
Maximum route speed: 3941952bps

Pingtest.net
-----------------
Line Quality = B
Ping = 87ms
Jitter = 12ms

Speedtest.net
------------------
Download = 1.47Mb/s
Upload - .33 Mb/s
Ping = 88ms

I have not used PingPlotter yet, but I would be happy to post/email those results as well to anyone that feels it would help.

I absolutely love everything about the OOMA, but I have got to get this delay resolved before my wife puts the end to this project. Maybe one of the “OOMA Super Support Guru’s” will have some suggestions.

I have a good relationship with my isp and feel that they would have no problem in working with me to resolve if I can provide him with some good data to identify the latency.

Any suggestions would be greatly appreciated.

Jeff

Re: The delay is excessive

Posted: Thu Jun 24, 2010 2:30 pm
by lbmofo
Do you have some "lite" version of DSL? If so, need to get the unrestricted version. If that's all you can get with DSL, I'd go to cable internet.