Sounds like a combination of packet loss and small TCP receive windows. If you can, grab a packet capture and make sure to get the TCP setup. That should show you what's happening under the hood.
Also, I should mention that I totally hosed the units in my first reply. :) That's what I get for hurrying. John On Fri, Oct 31, 2014 at 1:29 PM, Zachary Frederick <zcfreder...@gmail.com> wrote: > I apologize I should have said it starts out about 3 meg max and slows to > about 400kpbs for most of the transfer. > > > > On Oct 31, 2014, at 3:27 PM, John Neiberger <jneiber...@gmail.com> wrote: > > With a max bandwidth of 25 Mbps and a 40ms RTT, the max is more like > 14MB/s or 1.75 Mbps. > > > https://www.switch.ch/network/tools/tcp_throughput/index.html?mss=1460&rtt=80&loss=1e-06&bw=25&rtt2=35&win=64&Calculate=Calculate > > But that's only if either endpoint is stuck at a 64 KB receive window. A > quick packet capture would be able to see what was happening. Check the > TCP setup and make sure that both ends are doing TCP window scaling > properly. > > John > > On Fri, Oct 31, 2014 at 1:02 PM, Pedro Cavaca <pmsac.na...@gmail.com> > wrote: > >> On 31 October 2014 18:32, Zachary Frederick <zcfreder...@gmail.com> >> wrote: >> >> > We have been having a problem receiving software releases from our >> > developer. The releases are typically around 1G in size. The developer’s >> > connection is a 100m metro fiber with TW Telecom, our connection is a >> 25m >> > Comcast Enterprise Fiber. >> > >> > Our traffic graphs show very little utilization of our connection. >> > Typically on average we are at about 7 meg utilization of our 25. >> > >> > Every other partner that shares in our software development that >> receives >> > the software releases can receive the updates 3-4 times faster than we >> can. >> > >> > Typically we receive the releases at about 3mbps. >> > >> >> Are you using an application that uses TCP transport for the transfer? >> >> >> https://www.switch.ch/network/tools/tcp_throughput/index.html?mss=1460&rtt=38&loss=1e-06&Calculate=Calculate&bw=100&rtt2=80&win=64 >> >> 3Mbps looks about right. Time for a tune up >> >> >> > I have tried contacting Comcast Enterprise Tech support, however I’ve >> been >> > told that if I run a speed test from my connection and the test runs at >> the >> > speed we are paying for, there is very little they are willing to look >> into. >> > >> > Can anyone check on the Comcast Routers on the Tracert below, or is >> there >> > anything that can be throttling this connection between the two >> connections? >> > >> > Also, our firewall and connection is able to run at the full 25. We have >> > no throttling or QOS set to prevent a good connection to our developer. >> For >> > example, we can run a multi-threaded upload, in the middle of the >> night, to >> > Amazon Glacier storage and completely saturate our connection when doing >> > so. The firewall and connection is able to handle our full bandwidth >> > capacity during that backup. >> > >> > If there is any other information I can provide to help track this >> problem >> > down, please let me know. >> > >> > Thanks in advance, everyone! >> > >> > >> > Trace Route below: >> > >> > >> > >> > >> > 1 (172.16.150.1) 1.143 ms 1.132 ms 1.122 ms >> > >> > >> > 2 (173.227.204.1) 1.585 ms 1.583 ms 1.574 ms >> > >> > >> > 3 chi2-pr1-xe-0-3-0-0.us.twtelecom.net (66.192.245.166) 10.477 ms >> > 10.485 ms 10.478 ms >> > >> > >> > 4 x-eth-0-0-4-pe05.350ecermak.il.ibone.comcast.net (75.149.230.141) >> > 10.470 ms 10.465 ms 10.457 ms >> > >> > >> > 5 he-2-1-0-0-cr01.350ecermak.il.ibone.comcast.net (68.86.86.37) >> 10.733 >> > ms 10.731 ms he-2-0-0-0-cr01.350ecermak.il.ibone.comcast.net >> > (68.86.86.33) 12.146 ms >> > >> > >> > 6 be-10206-cr01.newyork.ny.ibone.comcast.net (68.86.86.225) 33.202 ms >> > 32.144 ms 32.127 ms >> > >> > >> > 7 68.86.91.30 (68.86.91.30) 41.508 ms 41.322 ms 41.599 ms >> > >> > >> > 8 te-0-0-0-1-sur01.greensburg.pa.pitt.comcast.net (69.139.168.26) >> > 38.196 ms te-0-0-0-3-sur01.greensburg.pa.pitt.comcast.net >> > (162.151.21.82) 44.644 ms >> te-0-0-0-0-sur01.greensburg.pa.pitt.comcast.net >> > (69.139.195.18) 38.266 ms >> > >> > >> > 9 (107.1.72.98) 39.781 ms 39.785 ms 39.912 ms >> > > >
