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Can Any Router Guarantee Bandwidth For VoIP?
cartman94501 writes "My wife and I use Vonage for Voice over IP at home, mainly for work-related phone calls so we don't have to give out our home number to clients and colleagues. Most of the time it works fine, but when I'm using BitTorrent or other high-bandwidth applications (purely for legal and non-copyright-violating purposes, of course), the call quality gets choppy. I have used my Linksys (not a WRT54G, so 'upgrading' it to Linux probably won't work) router's QoS feature to assign high priority to the MAC address of the Vonage box, low priority to the BitTorrent box, and medium quality to everything else, which helps a little, but not enough.
Is there a router out there that would allow me to reserve, say, 75-90kbps of bandwidth off the top for VoIP and never, ever allow any application to use that, regardless of whether there's a VoIP call going on at the moment or not?" (More below)
cartman 94501 continues: "That would solve my problem, but I fear I'd have to build a Linux box and learn all sorts of esoteric commands to really make that work. Are you aware of a commercially-available router that would allow me to accomplish this goal with some sort of ease? While I'm not prepared to pay four figures, I'm certainly not naïve enough to expect such a device to be available in the $50-100 range of your garden-variety wireless router. Wireless would be ideal, but if I could patch it in between my existing wireless router and the cable modem, and turn off QoS entirely on the existing router, that would work, too."
QOS should work if you set it up properly.
On my WRT-54GL with Tomato (others might work, Tomato is the easiest of ddwrt, openwrt in my experience), the QOS settings can be limited in just the way you want, with everything except the highest only being allowed only 75% of your upload, or whatever you want.
Downstream is a bit harder to restrict, since the queue is on the Telcom side of things, but you could do some QOS in your router there as well.
If I have nothing to hide, don't search me
Couldn't you do a low heat/low power CPU that doesn't need active cooling, RAM, and a USB thumb-drive to boot off of?
Computers allow humans to make mistakes at the fastest speeds known, with the possible exception of tequila and handguns
I'm not sure how you found your WRT54G lacking in CPU power because on my WRT54G v4, I had actually underclocked it to 183MHz and yet it worked just as well.
I run BitTorrent actively on two separate PCs, and at the same time, we have VoIP and we play delay-sensitive online games.
I did some crucial settings though... like setting the correct upstream and downstream capacities, reducing the TCP and UDP timeouts, and using HFSC as the packet scheduling algorithm (some have reported to try HTB if HFSC fails).
w00t
The OP doesn't say but probably doesn't have a cable modem, he more likely has ADSL from the phone company.
I have fought those problems with VOIP and a poor DSL line. With a WRT54G and that optional firmware, and it was an abject failure. We couldn't solve the ADSL line problems at our end.
The solution is probably going to be calling his provider and demanding they give him the speed he is paying for, and if he's not paying for enough speed he may have to pay for more line speed.
The trouble with DSL is it is not guaranteed bandwidth. It can completely stop working for more than enough time to screw up VOIP and there is likely nothing he can do about it.
Cable modem service is typically enough faster than ADSL from the phone company he is much less likely to have these sort of problems, unless maybe his provider has installed Sandvine traffic management equipment and that is screwing him up detecting his P2P usage and throttling his circuit. I don't know if Sandvine equipment throttles the whole circuit or not. Does it? Does anyone know?
The funny thing is you would never have these problems on an ISDN circuit, which though slow by todays bursty ADSL standards is guaranteed bandwidth, just like that corporate OC-48 you have at work. You get two FM radio quality voice channels on ISDN and it does work, guaranteed. If not they *have* to fix it.
Whereas on ADSL they just say "sorry bub". Then they maybe say "If you got your VOIP from us I bet it would work". But only because in that case they would *have* to fix it. Evil telcos, to be sure.
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