US Cable Support > Comcast HSI > Comcast Upload Issues

Comcast Upload Issues

100 MB/day is a MINISCULE amount of upload to allow. There must be something broken somewhere, because I highly doubt Comcast would purposely interrupt any upload that exceeded 100 MB.

What happens if you upload two things at the same time? Do they both die at ~50MB (assuming they both upload at the same rate). Or do they both make it to 100 MB?
--
He who is not contented with what he has, would not be contented with what he would like to have. -Socrates

They die in the ball park of 100mb combined. Sometimes it wont do it till 150mb/200mb but normal issue is 100mb.

The strange thing is the modem actually resets itself. The lights go out and then slowly boot back up when this happens.

Well, first thing I'd do is try replacing the cable modem, if the modem itself is resetting/rebooting.

Well Comcast tech just left 2 hours ago and replaced with a brand new one.

I even put in a new router since it was coming time to replace anyways.

Same problem. He also checked my old modem + the new one and said they both were in perfect shape.

Well, that's really odd. Did you show the tech that it was doing it while he was there?

If it's still doing it even after the truck roll, perhaps you'll have more luck getting in touch with someone from tier2 support or someone from the NOC.
--
He who is not contented with what he has, would not be contented with what he would like to have. -Socrates

reply to Pau_Bea
Pau_Bea, can you post traceroutes to Rapidshare and your grandma of your nieces? (Feel free to omit or obfuscate the final hop --see below-- if disclosing her IP concerns you.)

I thought maybe RapidShare might be cutting you off, but I checked and RapidShare has a 200 MB limit.

For those trying to reproduce -- I am seeing this today trying to upload a larger file (200+ MB) from Comcast.net to Verizon.net, but I'm also wireless on both sides and through two SoHo routers. I'll tear those off and wire directly to the modem and test again tomorrow.

What I'm doing:
1. Set up ProFTPd on my Verison DSL account
2. ftp myVZaddress and login
3. type "bin" to switch to binary upload mode
4. note that I cannot reach 100 MB upload without reset

What I think I've noticed:
1. RST is received on the Comcast side first (this is not the "two-way" RST seen with the Sandvine stuff from last year). The RST was not sent by my FTP server computer (but like I said, I have a SOHO router on each end that hasn't been eliminated yet.)
2. RST is received after a stall each time
3. The transfer sometimes has a few stalls

C:\Documents and Settings\robb>tracert XXX
 
Tracing route to XXX [71.111.XXX]
over a maximum of 30 hops:
 
  1     *        *        *     Request timed out.
  2     *        *        *     Request timed out.
  3    17 ms     9 ms     9 ms  68.85.149.1
  4    16 ms    20 ms     9 ms  te-9-2-ar01.beaverton.or.bverton.comcast.net [68.87.216.29]
  5    13 ms    17 ms    34 ms  te-0-4-0-1-cr01.portland.or.ibone.comcast.net [68.86.90.245]
  6    19 ms    15 ms    14 ms  pos-0-0-0-0-cr01.seattle.wa.ibone.comcast.net [68.86.85.205]
  7    84 ms   310 ms    32 ms  TenGigabitEthernet1-3.ar5.SEA1.gblx.net [64.212.32.157]
  8    14 ms    14 ms    14 ms  ge5-0-0-1000M.ar4.SEA1.gblx.net [67.17.73.41]
  9    17 ms    19 ms    15 ms  uunet-1.ar4.SEA1.gblx.net [64.215.195.222]
 10    28 ms    16 ms    17 ms  0.so-1-2-0.XT1.SEA1.ALTER.NET [152.63.106.2]
 11    16 ms    31 ms    38 ms  0.so-7-3-0.XT1.SEA7.ALTER.NET [152.63.104.226]
 12    15 ms    16 ms    27 ms  0.so-6-1-0.SEA01-BB-RTR1.verizon-gni.net [152.63.105.58]
 13    22 ms    33 ms    22 ms  P11-0.LCR-01.PTLDOR.verizon-gni.net [130.81.28.161]
 14    42 ms    23 ms    41 ms  G4-0-2103.DSL-03.PTLDOR.verizon-gni.net [130.81.33.229]
 15    53 ms    47 ms    43 ms  pool-71-111-XXX-XXX.ptldor.dsl-w.verizon.net [71.111.XXX.XXX]
 
Trace complete.
 

robb@topol015:~$ traceroute 24.21.33.XXX
traceroute to 24.21.33.XXX (24.21.33.XXX), 30 hops max, 40 byte packets
 1  L100.DSL-03.PTLDOR.verizon-gni.net (71.111.112.1)  60.678 ms  61.102 ms  62.387 ms
 2  G4-1.LCR-01.PTLDOR.verizon-gni.net (130.81.33.228)  63.884 ms  64.851 ms  67.444 ms
 3  130.81.28.160 (130.81.28.160)  73.354 ms  74.536 ms  76.164 ms
 4  0.so-7-1-0.XT1.SEA7.ALTER.NET (152.63.105.57)  79.603 ms  79.907 ms  81.013 ms
 5  0.so-2-0-0.XT1.SEA1.ALTER.NET (152.63.104.225)  84.177 ms  88.107 ms  82.482 ms
 6  POS6-0.BR2.SEA1.ALTER.NET (152.63.106.1)  82.781 ms  119.862 ms  30.161 ms
 7  so6-1-0-2488M.ar4.SEA1.gblx.net (64.215.195.221)  31.798 ms  34.022 ms  34.648 ms
 8  ge9-1-1000M.ar5.SEA1.gblx.net (67.17.73.42)  37.152 ms  37.759 ms  39.439 ms
 9  COMCAST-IP-SERVICES-LLC.TenGigabitEthernet1-3.ar5.SEA1.gblx.net (64.212.32.158)  60.539 ms  61.286 ms  62.966 ms
10  te-5-2-ar01.troutdale.or.bverton.comcast.net (68.86.90.238)  53.727 ms  59.387 ms  59.514 ms
11  68.85.243.182 (68.85.243.182)  59.642 ms  59.741 ms  59.862 ms
12  ge-4-1-0-ten08.beaverton.or.bverton.comcast.net (68.85.149.14)  35.414 ms  55.948 ms  44.659 ms
13 (my host)
 

Interesting. What if you upload ~90MB. Stop it manually, then resume the upload?

If you'd like to try uploading to me, let me know. We can see where it dies for you to me. I should be able to max out your upstream (assuming the windows are set high enough of course ). And of course I can to a pcap while it's running...

reply to Pau_Bea
i have actually uploaded about 5gb in 1 day without any disconnections, you could try WINRAR'ing your files in like 50mb archives or something instead of doing large files

although i have to agree this past 1 year their service has become quite poor

Well I did some tests with that I tried 10 10mb files to rapidshare. Same result cept I got DC 3-4 times.

I tried limiting upload to 50% of my max and reuploaded those 10 files again disconnected 2 times.

I tried 2 90mb files...this time I got disconnected 5 times.

Also how do you run a traceroutes?

With Windows, the command is tracert and you do it inside a command prompt window. With linux, there are several tools such as traceroute.

You'll want to find out what IP address you're connecting to. With Rapidshare, it's possibly a local CDN close to Arkansas so the best way to be accurate is to connect to rapidshare and start uploading. Then in a command prompt window do the command

netstat
... followed quickly by...
netstat -n

and look at your outgoing connections to rapidshare using port http (which is 80) in the first display (which has translations from IP addresses into dns names). Using that first display as a guide, you can look at the second display and find the same entry (this time you'll see IP addresses and port numbers ... http=80 ... but they're in the same order as the display with the DNS help, so you should be able to find the entry that shows the remote IP address that your system is talking with to reach rapidshare). That remote IP address for rapidshare is what we need you to use with traceroute.

tracert XX.XX.XX.XX
--
Robb Topolski -= funchords.com =- Hillsboro, Oregon -- KJ7RL
... Do something! ...

reply to Pau_Bea
This can't be a coincidence. I'm having the very same problem. I am on Comcast with a Motorola SB5100 Modem.

I use Jungledisk to backup my system to Amazon S3. and now I cannot backup any files over about 40MB. Even 10MB files take several retries to complete correctly.

I tried scp and rsync from Linux and all fail with >40MB files.

This all worked well a few weeks ago.

What's up with Comcast?

reply to Pau_Bea
Well I did some new searches and I found a interesting post

I did some google searches on some new terms and I found this site
»www.p2pnet.net/story/17074

It said
If you’re a Comcast user and only occasionally upload large files for extended lengths of time, the issue for you isn’t the bandwidth cap. The issue will be their strange throttling scheme, which puts users in a “penalty box” for using more than 70% of available bandwidth in any 15 minute window and releases them from the box when their activity drops below 50%.

Testing this out now.

If they are only allowing me 50% of the connection I payed for...I should only have to pay for 50% of total HIS bill I get.

Others try this out and see if it does anything for them.

Hope the FCC crucify them over this. Think I am gonna start shopping for another ISP. It's bad enough Comcast lies to their customers and hide things but to now sell a connection you can't use is no better then what thieves do.

For what it's worth, a friend of mine with Comcast in El Dorado Hills, CA (near Sacramento) let me login and do some FTP uploading from him to my FiOS connection.

He pushed data to me @ 278 KB/s solid for the duration of a randomly generated 64 MB file. The summary from the ftp client shows an average of 273 K/s actually:

Well I been doing 40kb for about 2 hours now...since the girly isn't online I wont have to worry about her getting made at the DC.

But so far no issues have occurred. Trying 50kb now and see if it happens.

Well both my grandma and myself are Comcast users. Well least for now...switching to FIOS Monday.

I am curious could you get your buddy to upload 2 100mb files to RS at the same time?
See if its just sites Comcast thinks we shouldn't be uploading on or comcast/comcast?

I can ask him tomorrow to try uploading to RS (rapidshare?), but I don't know if he has an account or anything.

If it's just doing this for certain destination hosts, that's even worse because that shows some potential bad intent.
--
He who is not contented with what he has, would not be contented with what he would like to have. -Socrates