dslreports logo
site
 
    All Forums Hot Topics Gallery
spc

spacer




how-to block ads


Search Topic:
uniqs
3085
share rss forum feed

marcad2000

join:2009-07-08

[Speed] Comcast Throttling Video Stream?

I live in overseas half the year and half the year back in the SF Bay Area for the rest. I pay for Comcast all year whether I am there or not. I use a "Slingbox" to watch Comcast while overseas.

However, it seems, for the last few weeks, that at 4pm PST each day, my Sling feed drops from 900kbsps to 24Kbps at best and does not return to "normal" (900kbps) until between 8-40am. Obviously, my streaming of video is not usable.

So, is COMCAST throttling or limiting bandwidth?

Thanks



beachintech
There's sand in my tool bag
Premium
join:2008-01-06
kudos:5

I doubt it - There is a lot of network between CA and "over seas". Linking around the world is expensive, especially at peak times.
--
Tech at the Beach.



Cjaiceman
Premium,MVM
join:2004-10-12
Parker, CO
kudos:2

1 edit
reply to marcad2000

No, Comcast does not throttle your connection, they do however traffic shape your connection if your using a lot of bandwidth. To be classified as such two conditions MUST exist for your connection to be shaped:
1) You are using more than 70% of your bandwidth in upstream or downstream for more than 15 minutes consecutively.
2) Your node/CMTS is congested, and you are one of the main causes of the congestion.

More details are here: »New Comcast Throttling System 100% Online

quote:
Comcast says that sustained use of 70% of your up or downstream throughput triggers the BE state, at which point you'll find your traffic priority lowered until your usage drops to 50% of your provisioned upstream or downstream bandwidth for "a period of approximately 15 minutes." A throttled Comcast user being placed in a BE state "may or may not result in the user's traffic being delayed or, in extreme cases, dropped before PBE traffic is dropped."
Edit - Beachintech, you beat me to it, and I have to agree. Streaming media across the seas can be difficult, and the I doubt the Comcast traffic shaping system is to blame.

--
Duct tape is like The Force – it has a light side and a dark side, and it binds the Universe together

andyross
Premium,MVM
join:2003-05-04
Schaumburg, IL
reply to marcad2000

Where overseas are you streaming TO? Many ISP's, especially outside the US, are very aggressive throttlers. Just talk to anybody from Canada!


marcad2000

join:2009-07-08
reply to marcad2000

I am in fact now in Thailand and now that my ISP is having some problems with their international routers and bandwidth.

However, that said, after losing my Concast stream at 6am (not a busy time here) in Thailand or 4pm PST, I immediately went to MSNBC and was downloading a video replay at 2mbs clear as a bell though my local ISP.

That's why I was concerned about Concast throttling or shaping. From 10pm to 6 am my time (8am to 4pm PST) everything was nearly perfect at 1mbs upload for nearly eight hours straight, then POOF!!!!Gone, retries 10's of minutes later and still no go. So how does that fit into Concasts 'shaping' model?

Thanks,


Chaldo

join:2008-03-18
West Bloomfield, MI

1 edit

Well I understand what your point is about, but you have to remember routers do not take the same route to each destination, one route to (your comcast) can be the best route, but it would be congested. The route you are taking for MSNBC could not be congested, also MSNBC can also not be congested as much so it will help you out, Comcast could be having problems or congestion at that time. It's a lot of factors that play in this game.



Puzzled

@comcast.net
reply to marcad2000

Comcast has recently opened the modems in my node from 6/8 to 12 Mbs. Downstream has become choppy, and in some cases, brought to a halt. Maybe they have to tune some things, or maybe this is the new system i9n action. But now I noticed that many video streams will no longer work. PBS works sometimes, or it may abruptly halt and stop communicating altogether. Restarting the video gets me nothing. I can go to ABC, CBS, NBC, the majors, and the video streams do not work at all. Not even intermittently like when those feeds get loaded down.

As far as I can tell, these video streams are being cut off. I speed test at 16 down and 3.5 up. The current video streams rarely go over 1.5 Mbs in a burst, and generally stay below 1 Mbs. Personally, I don't believe the 70% bit. Plus I have had their customer reps just lie to me way too many times for me to trust that company. They're doing exactly what makes sense. Trying to keep people purchasing their overpriced TV product, which to me, is not only horrible these days, but is half advertising. That's my take.



beachintech
There's sand in my tool bag
Premium
join:2008-01-06
kudos:5

2 edits
reply to marcad2000

puzzled - Most of that, is prob the content provider and their isp's. Or - it's your local computer / network. Too many variables to make definitive statements like you have that it must be big evil C*.

as for the OP - even to MSNBC's site, there are a lot of routes to take and they most likely have a mirror very close to you (geographically closer than California) which will help your streaming speeds. I still do not believe this is a comcast problem. You also haven't posted anything showing that it is.
--
Tech at the Beach.


marcad2000

join:2009-07-08

1 edit

said by beachintech:

puzzled - you have a lot to learn about network topology and how streaming works. Most of that, is prob the content provider and their isp's. Or - it's your local computer / network. Too many variables to make definitive statements like you have that it must be big evil C*.

as for the OP - even to MSNBC's site, there are a lot of routes to take and they most likely have a mirror very close to you (geographically closer than California) which will help your streaming speeds. I still do not believe this is a comcast problem. You also haven't posted anything showing that it is.
beachintech-

What would would you like me to be to be able to show?


gar187er
I do this for a living

join:2006-06-24
Dover, DE
kudos:4
reply to marcad2000

tracert's for one, to show you are going through 30 hops to get to your sling box....lol



jlivingood
Premium,VIP
join:2007-10-28
Philadelphia, PA
kudos:2
reply to marcad2000

Feel free to PM me your modem's MAC address if you have it and I can check the congestion mgmt system for you. But in any case, we do not throttle video or other specific protocols or applications.

As other posters have said, it would be very helpful to post a traceroute. I recommend you post one when everything is working fine, as well as one when things seem choppy. ISPs can vary their routes by time of day due to changes in the cost of routes and other factors. From where you are to the SF Bay, there are a lot of points along the way that could be causing the problem.
--
JL
Comcast



JohnInSJ
Premium
join:2003-09-22
Aptos, CA
reply to marcad2000

What is your speed tier?

Per: »Comcast High Speed Internet FAQ »What are the actual Provisioned Speeds?

Even if it's 6/1, the uplink should be
Upstream: 1100 kbps

It's either 1mbps up, or >=2mbps. You're using 900kbps. That's either 81% of your max uplink, or less then half.

So, if you're on a 1mbps up tier, you could easily be bumping into the traffic shaping. If not, no way it could be that.

You're trying to send your bits over the pacific ocean during what is likely the peak usage time for trans-pacific data. I'm surprised it works at all.

You could try a simple test of switching to a lower quality video stream... something in the 500-600kbit range should be well under the throttle threshold.
--
My place : »www.schettino.us

Expand your moderator at work