WRTP54G QoS Priority for Voice Traffic not sufficient?

Posts: 40 · Full Forum Member Joined: Jul 03, 2005 Posts: 40

I'm a recent Vonage customer, having gotten in on the free-after-372-rebates Linksys WRTP54G router. My SBC number was transferred two days ago so I've finally started to use the service. I have Comcast Cable Modem service and so theoretically have 4 Mbps down / 384 kbps up. And I haven't had much problem getting close to 384 kbps via bittorrents or eMule or uploading a file via HTTP.

Today I decided to do a check that the router would properly give the voice traffic priority. I started eMule and set it to use 320 Kbps upload speed. I then placed a call from my Vonage phone to my cell phone, and left a lengthy voicemail, all the while watching both eMule's upload bandwidth report as well as Windows XP's Task Manager network adapter usage (specifying that it show sent and received bandwidth separately). The Vonage call didn't seem to make a bit of difference to the upload bandwidth, although after ending it the router seemed to kill most active connections--eMule dropped down to 0 Kbps, IM connections were reset, etc. Not surprisingly the voicemail I left sounded horrible... very choppy, coming in and out.

This lead to some web searching and an hour-long call to Vonage, the first 30 minutes being taken up by a support person who couldn't seem to understand that I was telling him I indeed had sufficient upload bandwidth to use Voip but that the problem was that the router wasn't properly giving voice traffic priority. Eventually he transferred me to a Tier 2 guy, who told me I needed the 1.00.29 firmware upgrade (which I had read about on the linksysinfo.org thread). He proceeded to email it to me and gave me the instructions that I had already read. The upgrade worked (though the level 2 guy didn't seem ready for the "Upgrade are failed!" error message, or the double-progress cycle).

After ending the call and reconfiguring the router to my prior settings, I tested it again. This time I started a 1GB file upload on http://yousendit.com, and then placed a call. Before the call the file transfer was using right around 380Kbps, so it was doing a good job of maxing my upload bandwidth. During the call it dropped to between 230 and 330 kbps at the extremes, but probably consistently averaging somewhere between 270 and 280 kbps. Which suggests that the router was giving Vonage an average of about 100-110 Kbps.

So this would appear to be better behavior with 1.00.29 than with 1.00.18, but the result still is that my outgoing call audio sucked. Once again the other end of my call heard constant clipping from the continual gaps in what I was saying. I could hear fine as I was barely using my 4.0 Mbps download bandwidth.

The Vonage website speed test reported my bandwidth (after turning off any uploading programs) at 4.07 Mbps down / 363 Kbps up. This should be more than enough to have a high quality call and still have bandwidth over for TCP connections. But that's clearly not happening for me. Among the things I'm wondering are:

1. Has anyone else had this same faulty QoS experience with their WRTP54G (particularly if you're running 1.00.29)
2. Is there any router configuration setting I can change to reserve more bandwidth for the voice traffic (my general understanding is that the answer is "no", because the voice traffic is hard coded to "high" priority and so theoretically should all get through).
3. How much upload bandwidth does a highest-quality call use? Vonage's website (and their bandwidth saver) seem to suggest 90 Kbps (and I have my bandwidth saver configuration at the 90 Kbps max), but I seem to recall reading that it would use a fair bit more than that. [marq=right]

And if anyone has any other suggestions or solutions (aside from manually restricting my computers from using upstream bandwidth during phone calls) those would be much appreciated too. Thanks.

Edited to add: In case it's useful, here's a typical result of the Vonage Voip Speed Test, with nothing else running:

Download 4,020,336 bps
Upload 362,872 bps
QOS 93%
RTT 64 ms
MaxPause 47 ms

Posts: 3198 · Posted: Mon Jul 04, 2005 8:56 am Post subject:

I would like to know what the results are with no uploads going on. that would have a pretty big impact on where to start troubleshooting.

Posts: 40 · Full Forum Member Joined: Jul 03, 2005 Posts: 40

With no uploading the call quality is great in both directions.

Posts: 2 · Posted: Mon Jul 04, 2005 3:33 pm Post subject:

I had this same problem with the WRTP54G. I was on the phone with Vonage for over two hours trying to explain to a tech about the QOS problem. I also tried the newer firmware. In the end, I had to take matters in my own hands. I took the WRTP54G back and replaced it with a PAP2 behind a WRT54G running Sveasoft's Talisman firmware. This seemed to do the trick. I have full control over the QOS now. There are other setups that work well too. You can run the newest stock firmware for the WRT54G or run a dedicated linux software router.

Dale

Posts: 40 · Full Forum Member Joined: Jul 03, 2005 Posts: 40

Yeah, if I hadn't already cut up my box so that I could send off the various rebates, I'd be very tempted to return this router. I just had a friend who also has a WRTP54G (that I helped him upgrade to 1.00.29) duplicate the same experiment--talk to me over his Vonage phone and during the conversation initiate a file upload from yousendit.com--and the result was exactly the same. While the file upload is going on, his voice got all choppy, just as my voice does to the other end of a conversation when I start using my upload bandwidth. The quality immediately returns back to fine during the conversation when the file transfer is ended. I wouldn't be surprised if many other owners of the WRTP54G, even running 1.00.29, had the exact same experience, though many might not be aware because their computers aren't typically trying to use all of their upload bandwidth when they place a call.

If any other owners of the WRTP54G want to see if they're affected by the same problem, it's fairly easy to test. Ideally you'll first make sure that no computers on your home network are using any upload bandwidth. Next, find a large file on one computer (preferably one with a wired connection to the router), anywhere from a few megabytes up to a gigabyte--the size doesn't really matter, you just want something that can't be fully uploaded within the brief time that you'll experiment with call quality. Go to yousendit.com. Put in your own email address as the destination, and Browse to the the large file. Don't hit send yet. Make a call with your Vonage phone--either to a helpful friend or perhaps to some external voicemail, like your work or cell phone--and start talking. Then hit click the send button on the yousendit page, and keep talking. Ask your friend (or check your voicemail later) if your voice sounds worse--if your experience is like mine your voice will have brief but regularly-occurring dropouts. You can end the file upload by browsing to any other web page from the yousendit page, after which you can check if your voice quality went back to normal.

If you want to use Windows Task manager to see the bandwidth that you're computer is using during this test (at least in XP, I can't remember if prior editions included a Networking tab), then do the following. Start the Task Manager (I use the Ctrl-Shift-Esc shortcut), and select the Networking tab. Under View->Select Columns make sure at least Link Speed and Bytes Sent Throughput is checked (the latter won't be on by default). At the bottom portion of the task manager you should see those 2 columns, among others, for your network adapter. If you are using a wired connection your link speed will probably be 100 Mbps, in which case 1% of Byte Sent Throughput corresponds to 1 Mbps, so 0.13% would be about 130 kbps upload, 0.38% would be 380 kbps, etc. If you're using a wireless connection you'll have a more complicated conversion factor. You can monitor this Byte Sent Throughput column to see how much upload bandwidth your computer is using. It will fluctuate a bit during the file transfer (even if you don't have a phone call active) but that's just normal TCP behavior. If you want to see a graph of your upload bandwidth go to View->Network Adapter History-> and I'd recommend unchecking Bytes Total and checking Bytes Sent and Bytes Received. Your upload bandwidth will be the red line.

Another data point I've gathered... the call isn't affected if I have a background upload restricted to 80 kbps. So it's not like the mere presence of an upload will screw up the call quality... it really seems like with 1.00.29 the router does reserve some bandwidth for the Vonage call, but not quite enough. Either that or it has a poor priority queueing algorithm that allows lower priority data traffic to still interfere with the Voip traffic. The net result is a phone call where my speech is interrupted by fairly regular brief dropouts. There's never a long period of silence (or a long period of high quality speech), just fairly regular choppiness.

Whatever the root cause, it was fairly trivial for me to test, which makes me fairly surprised that this product made it to market in this state (though I probably shouldn't be).

Posts: 6 · New Forum Member Joined: Aug 26, 2005 Posts: 6

I am also a new owner of the Linksys WRTP54G. I bought this router to resolve the QOS problem I was having with my PA2. The idea was that if the two phone ports were on board the router, the qos bits wouldn't get missed/dropped as before. Wrong.

Note that the only issue I have with QOS is running something similar to Netmeeting (a virtual classroom app). My voice quality is fine until I start, for example, scrolling a graphic in the virtual classroom. Then people on the phone start complaining about my voice breaking up. When I stop scrolling, the quality returns to normal. My current workaround is to try and not talk while I am scrolling.

I saw that the router can be configured for QoS under the Applications and Games, so I talked to Linksys and they said I need to reconfigure my "Voice" QOS which is under the Voice menu - which can only be accessed by Vonage. They said that QoS under Apps and Games will not affect Voip.

I've got a call into Vonage right now. I too, have already sent in for the rebate, so returning the product is not an option.

Posts: 24 · Vonage Forum Associate Joined: Aug 17, 2005 Posts: 24

Please keep this post going. I was getting ready to purchase that very router and load the Sveasoft firmware but I want to see how this progresses first.

I too, am I heavy bandwidth user and experience poor OUTBOUND voice quality when I use GoToMeeting (which is frequent) and especially when I am scrolling within GoToMeeting.

It appears that neither of you are using the Sveasoft firmware. Can anyone comment on whether the Sveasoft firmware provides more options for QOS'ing the voice data over any other traffic?

Posts: 216 · Posted: Fri Aug 26, 2005 2:05 pm Post subject:

You cannot use the Sveasoft firmware on a WRTP54G.

Posts: 6 · New Forum Member Joined: Aug 26, 2005 Posts: 6

Is anyone using the WRTP54G router with Voip experiencing 1 or 2 beeps when placing a call - I hear them when I enter the last number I am dialing, then there is a slight pause and the phone starts ringing.

Linksys didn't have a clue what that might be about and starting telling me I might want to play around with my MTU values (currently set to auto). But when I pressed her on whether this was related to the beeping, she admitted she had no idea.

JLD

Posts: 40 · Full Forum Member Joined: Jul 03, 2005 Posts: 40

JLD, I'd be interested to know if Vonage responded with anything useful. The seemingly knowledgeable Tier 2 Vonage tech I talked to basically made it sound like claims of providing QoS were pretty much bogus, as there were too many cable modem/ISP variables for them to make sure their router/adapter hardware could work properly.