Posted: Tue Mar 11, 2008 15:58 Post subject: TCP Vegas makes QoS unnecessary?
I have been struggling with my Cable Modem internet connection to minimize packet loss & packet delay when uploading at full, uncapped speed.
Up until now, I had been using QoS to cap my upload, as the docs say, to 90% or so of my maximum upload. This requires me to accurately determine what my maximum upload rate is, and thanks to comcast & speedboost, this varies quite a lot.
Then I discovered TCP Vegas congestion control. According to wikipedia, TCP Vegas tunes the network performance based on packet delay instead of packet loss. Sweet! So I disabled QoS, enabled tcp_vegas, and played with it a bit. These options in the firewall commands have made all of my packet delay problems disappear! I see ~50ms pings while uploading even after speedboost has worn off.
Joined: 07 Jun 2006 Posts: 980 Location: Coal Creek Canyon, Colorado
Posted: Tue Mar 11, 2008 16:50 Post subject:
on what device did you enable this (computer? DD-router ? Cable modem ?) and how did you do that ? _________________ linksys GSv2, Gv4, Gv2, GLv1, G-TM, Buffalo wbr2, whr, whr-hp, whr-g125, wli-tx4-g54hp, Moto wr850gp, Alix.3C2
I did this on my dd-wrt v24 RC3 enabled Linksys WRT54GL router. I believe that dd-wrt has always supported multiple tcp congestion control algorithms. This is a module in the linux kernel. By default, dd-wrt uses tcp_westwood while openwrt uses bic.
1) Click Administration
2) Click Commands
3) Enter the code above
4) Click "Save Firewall"
5) Reboot router
Joined: 07 Jun 2006 Posts: 980 Location: Coal Creek Canyon, Colorado
Posted: Tue Mar 11, 2008 19:30 Post subject:
Ok -- thanks I re-read your first port more closely and it makes sense.
I wonder if this is only effective in a routed configurations -- would this do any good for a client-bridged or an AP-only ? _________________ linksys GSv2, Gv4, Gv2, GLv1, G-TM, Buffalo wbr2, whr, whr-hp, whr-g125, wli-tx4-g54hp, Moto wr850gp, Alix.3C2
Posted: Tue Apr 15, 2008 3:30 Post subject: Re: TCP Vegas makes QoS unnecessary?
p00nka wrote:
I have been struggling with my Cable Modem internet connection to minimize packet loss & packet delay when uploading at full, uncapped speed.
Up until now, I had been using QoS to cap my upload, as the docs say, to 90% or so of my maximum upload. This requires me to accurately determine what my maximum upload rate is, and thanks to comcast & speedboost, this varies quite a lot.
Then I discovered TCP Vegas congestion control. According to wikipedia, TCP Vegas tunes the network performance based on packet delay instead of packet loss. Sweet! So I disabled QoS, enabled tcp_vegas, and played with it a bit. These options in the firewall commands have made all of my packet delay problems disappear! I see ~50ms pings while uploading even after speedboost has worn off.
Im using it with DSL (PPPOE) and works like a charm. i also have QoS enabled though and it works great!
So you are using both at the same time. Have you done any tests with just the tcp_vegas alone?
I only enabled the tcp_vegas without QoS and my FiOS definitely has higher priority over downloading files.
[EDIT] - I guess priority isn't the right word here...I get constancy in my VoD downloads would be a better way to put it.
What are you using QoS for?
redhawk
I used TCP vegas alone, everything ran like a charm but BitTorrent and web browsing were both slow, VOIP was great. Enabled QoS (HTB) and set my bandwidth to 80% available and web/VOIP worked fast! The Bittorrent downloads were slowed to a crawl but thats what i wanted!
Posted: Wed Apr 16, 2008 22:23 Post subject: TCP Vegas makes QoS unnecessary?
I try this too. Seems to be good thing!
It works, but i'm not sure yet if i need QoS. I turned QoS off (used primary for voip). I will see if vegas alone is enough.
My concern about using vegas and QoS - they would be conflicting if used simultaneously for trafic controlling. Any ideas?
