dslreports logo
site
 
    All Forums Hot Topics Gallery
spc

spacer




how-to block ads


Search Topic:
uniqs
2
share rss forum feed


TSI Gabe
Premium,VIP
join:2007-01-03
Chatham, ON
kudos:7
reply to pph

Re: [Cable] Connection grinds to a halt when uploading...

This is normal, even on a Gbps+ connection, when you get close to the saturation point on your upload channel your TCP sessions aren't getting ACK'd back or at least not fast enough and causes TCP to scale down.

The issue is aggravated even further on DSL or Cable since they are asynchronous



NotNormal

@bell.ca

This is nowhere near normal. The op states they have a 18000/512 service where a upload at a mere 128kbps chokes the download to 200. Using 128 out of 512 should not be anywhere near saturating the upload.



TSI Gabe
Premium,VIP
join:2007-01-03
Chatham, ON
kudos:7

The OP did not specify exactly what speed he was uploading at the time of the test. I suspect that it was more than 10KB/s since it was a dropbox upload which normally takes whatever bandwidth you have available.


BrianON

join:2011-09-30
Ottawa, ON
Reviews:
·TekSavvy Cable
reply to TSI Gabe

Sure the behaviour is normal for a saturated upstream connection but from the information posted I think problem isn't local to the user or with the backhaul link to Teksavvy. That means someplace between those there *IS* a problem. A miss-configured port, router, wrong cables used or whatever.

What node people are on might help track down the problem. I am on Ottawa's richmond and do not have problems.



TSI Gabe
Premium,VIP
join:2007-01-03
Chatham, ON
kudos:7

one thing that pops to mind is that somehow the ethernet connection to the modem negotiated in half-duplex. I've seen this a few times



random

@teksavvy.com

>one thing that pops to mind is that somehow the ethernet connection to the modem negotiated in half-duplex.

The data rate is 1Gbps (or 100Mbps for older routers). Transferring 10KBytes/sec would be on the order of 100kbps of data which would only take up a tiny fraction of the time slots. That's 0.1/100 or 0.1/1000 of the time slots.

Same type of linear thinking reasoning that tell people to check Ethernet cables or the power supply when the person can see the modem webpage. A big waste of time that shows that you can't debug systematically.